Rainfall Structure of Thar The Great Indian Desert

Rainfall Structure of Thar The Great Indian Desert S. S. Singh, Mukesh Chauhan & Roop Narayan Kumawat Meteorological Centre, Jaipur India Meteorological Department New Delhi

DOCUMENT AND DATA CONTROL SHEET 1 Title of the report 2 Authors 3 Originating Unit Rainfall Structure of Thar- The great Indian desert S. S. Singh, Mukesh Chauhan & Roop Narayan Kumawat RMC New Delhi and Meteorological Centre, Jaipur 4 Type of Document Scientific Report 5 No. of pages and figures 75 and 84 6 No. of references 1 7 Key words Arithmetic Mean (AM), Coefficient of variation (CV), Standard deviation (SD), Percentage of departure from long period average (% DEP), and Long period average (LPA). 8 Security classification Unclassified 9 Distribution Unrestricted 1 Date of Publication April, 214 11 Abstract The report contains daily, weekly, monthly, seasonal and annual rainfall summaries for different districts of the Thar Desert of Rajasthan. The seasonal statement contains the monthly rainfall distribution, extremes and its variability. The probability of occurrence of wet and dry weeks is also described in detail.

CONTENTS Chapter I Geography and Physiography 1 Chapter II General Climate 12 Chapter III Rainfall features 17 Chapter IV Winter Season 29 Chapter V Summer Season 31 Chapter VI Monsoon Season 33 Chapter VII Post Monsoon Season 39 Chapter VIII Rainfall Features Annual 41 Chapter IX Extreme Rainfall 5 Chapter X Tables 66

Foreword The most parts of South West Rajasthan are part of Thar Desert. The economy of this region is mainly dependent upon agriculture and animal husbandry. The total annual rainfall of this region is also significantly less than the other parts of the state. Its geographical location is such that this region is mostly dependent upon rain water. The other sources of water like rivers, lakes and water reservoirs / dams, etc, are almost nil in the region. This region has lowest annual normal rainfall in the country. The period of monsoon over this region is shortest (two months) in the whole country. Most parts of this region receive very little rain and it has a large variability on temporal and spatial scale. Drinking and other water requirements for living beings are basically fulfilled with rain water only. Kharif crops are totally rain fed in the region and production varies with the amount and frequency of rainfall. Rain is thus the primary and most important source for survival. Bearing the above facts in mind, it becomes essential to know the rainfall features over the Indian Thar region. These features are important tools for planning purposes in various disciplines like water management, agriculture operations, industrial development, etc. The present booklet is an effort to summarise the district wise rainfall features of the Thar Desert. The report contains daily, weekly, monthly, seasonal and annual rainfall summaries for different districts of the Thar Desert of Rajasthan. The seasonal statement contains the monthly rainfall distribution, extremes and its variability. The probability of occurrence of wet and dry weeks is also described in detail. I appreciate the authors for their valued contribution in bringing out this Monograph Thar Desert of Rajasthan. I am sure people of the region, the state administrators and the planners will find this publication very useful. April, 214 New Delhi L. S. Rathore Director General of Meteorology India Meteorological Department

Summary The most parts of South West Rajasthan are part of Thar Desert. This region has lowest annual normal rainfall in the country its geographical location is such that this region is mostly dependent upon rain water. The period of monsoon over this region is shortest (two months) in the whole country. Drinking and other water requirements for living beings are basically fulfilled with rain water only. Kharif crops are totally rain fed in the region and production varies with the amount and frequency of rainfall. Rain is thus the primary and most important source for survival. The report contains daily, weekly, monthly, seasonal and annual rainfall summaries for different districts of the Thar Desert of Rajasthan. The seasonal statement contains the monthly rainfall distribution, extremes and its variability. The probability of occurrence of wet and dry weeks is also described in detail. These features are important tools for planning purposes in various disciplines like water management, agriculture operations, industrial development, etc.

CHAPTER - I ======================================================================= Geography and Physiography Location 1.1 The Thar Desert of Rajasthan, also known as the Great Indian Desert is a large arid region in the northwestern part of the Indian subcontinent and forms a natural boundary running along the border between India and Pakistan with an area of more than 1, km 2 within the Indian state of Rajasthan and covering mainly the districts of Jaisalmer, Barmer, Bikaner and Jodhpur and some region of the states of Punjab and Haryana. It extends from the Sutlej river and is surrounded by the Aravali ranges on the east, on the south by the salt marsh known as the Great Rann of Kutch (parts of which are sometimes included in the Thar), and on the west by the Indus river in Pakistan. Its boundary to the large thorny steppe to the north is ill-defined. It lies mostly in Rajasthan and extends into the southern portion of Haryana and Punjab states and into northern Gujarat state. Fig.1.1 The position of Thar Desert Fig.1.2 The position of Thar Desert 1

Physiography and Geology 1.2 The Thar Desert slopes imperceptibly towards the Indus plain and surface unevenness is mainly due to sand dunes. The dunes in the south are higher, sometimes rising upto 152 m whereas in the north they are lower and rise to 16 m above the ground level. The Aravali forms the main landmark to the south-east of Thar Desert. The soils of this region are sandy to sandy-loam in texture. The consistency and depth varies according to the topographical features. Some of these soils contain a high percentage of soluble salts in the lower horizons, turning water in the wells poisonous. Origin 1.3 The origin of the Thar Desert is a controversial subject. Some consider it to be 4 to 1, years old, whereas others state that aridity started in this region much earlier. Another theory states that area turned to desert recently perhaps around 2-15 BC. Around this time the Ghaggar-Hakra ceased to be a major river. It now terminates in the desert but at one time was a water source for the Indus Valley Civilization centre of Mohen-jo-daro. It has been observed through remote sensing techniques that Late Quaternary climatic changes and geotectonic changes have played a significant role in modifying the drainage courses in this part and a large number of palaeo-channels exist. 1.4 Most studies did not share the opinion that the palaeochannels of the Sarasvati river coincide with the bed of the present-day Ghaggar and believe that the Sutlej along with the Yamuna once flowed into the present riverbed. It has been postulated that the Sutlej was the main tributary of the Ghaggar and that subsequently the tectonic movements might have forced the Sutlej westwards, the Yamuna eastwards and thus dried up the Ghaggar-Hakra. 2

Thar in Ancient Literature Fig. 1.3 The position of Thar Desert Fig.1.4 Course of Sarasvati River through (Yellow colour) Thar Desert in Iron Age Vedic India 1.5 The Sarasvati river is one of the chief Rigvedic rivers mentioned in ancient Hindu texts. The Nadistuti hymn in the Rigveda (1.75) mentions the Sarasvati between the Yamuna in the east and the Sutlej in the west, and later Vedic texts like Tandya and Jaiminiya Brahmanas as well as the Mahabharata mention that the Sarasvati dried up in a desert. Agriculture 1.6 The Thar is one of most heavily populated desert areas in the world and the main occupation of people living here is agriculture and animal husbandry. Because of the large variability in rainfall on temporal and spatial scale, agriculture is not a dependable proposition in this area as after the rainy season, at least 33% of crops fail. Animal husbandry, trees and grasses, intercropped with vegetables or fruit trees, is the 3

most viable model for arid and drought-prone regions. The region faces frequent droughts. Overgrazing due to high animal populations, wind and water erosion, mining and other industries result in serious land degradation. Fig. 1.5 Bajra is the main kharif crop in Thar 1.7 The agricultural production is mainly from the Kharif crops. The Kharif crops are the crops that are seeded in the months of June and July and grown in the rainy season. These crops are harvested in September and October and include bajra, pulses such as guar, jowar (Sorghum vulgare), maize (zea mays), sesame and groundnuts. In past few decades the development of canals, tube wells etc. has changed crop pattern. Now the desert districts in Rajasthan have started producing Rabi crops like wheat, mustard, cumin seed and other cash crops also. Thar region of Rajasthan is the main opium producer and consumer area. 4

Livestock Fig.1.6 Camel ride in the Thar Desert near Jaisalmer 1.8 In the last few years, the Rajasthan desert has seen many changes, including a manifold increase of both the human and animal population. Animal husbandry has become popular due to the difficult farming conditions. At present, there are ten times more animals per person in Rajasthan than the national average, and overgrazing is also a factor affecting the environment. A large number of farmers in Thar Desert depend on animal husbandry for their livelihood. Cow, buffalo, sheep, goats, camel and ox consist of major cattle population. Barmer district has the highest cattle population out of which sheep and goats are in majority. Thar region of Rajasthan is the biggest wool-producing area in India. Of the total wool production in India, 4-5% comes from Rajasthan. The most important tree species in terms of providing a livelihood in Thar Desert communities is Procopius cineraria. Energy 1.9 The Thar Desert is an ideal place for generation of electricity from wind power. According to an estimate, Rajasthan state has got a potential of 55 Megawatt wind power generation. Solar energy also has a great potential in this region as most of the days during a year are cloud free. 5

Salt Water Lakes 1.1 There are a number of salt water lakes in Thar Desert. These are Sambhar, Pachpadra, Tal Chhapar, Phalodi and Lunkaransar where Sodium chloride salt is produced from salt water whereas Didwana lake produces Sodium Sulphate salt. People Fig.1.7 Huts in the Thar Desert 1.11 About 4% of the total population of Rajasthan state lives in Thar Desert. The main occupation of the people in this region is agriculture and animal husbandry. In past years there has been a tremendous increase in human population as well as animal population. This has led to improper control of grazing and extensive cultivation resulting in the deterioration of vegetation resources. The increase of human and livestock population in the desert has led to deterioration in the ecosystem resulting in degradation of soil fertility. The Thar Desert is the most densely populated desert in the world, with a population density of 83 people per km 2 v/s 7 in other deserts. Jodhpur, the largest city in the region, lies in the scrub forest zone. Bikaner and Jaisalmer are located in the desert proper. 6

Water Sources Fig. 1.8 Johads are common water sources Fig. 1.9 Tanks for drinking water Fig. 1.1 Course of River Luni 7

Fig. 1.11 River Map of Rajasthan 1.12 Natural (tobas) or man-made (johads), both types of small, intermittent ponds, are often the only source of water for animals and humans in the true desert areas. The river Luni is the only natural water source that drains inside a lake in the desert. It originates in the Pushkar valley of the Aravali Range, near Ajmer and ends in the marshy lands of Rann of Kutch in Gujarat, after travelling a distance of 53 km. It is a rainy season river. 1.13 In the recent developments, the Rajasthan Canal system is the major irrigation scheme of the Thar Desert which helps to check spreading of the desert to fertile areas. It is world's largest irrigation system which is being extended in an attempt to make the desert arable. It runs south-southwest in Punjab and Haryana but mainly in Rajasthan 8

for a total of 65 kilometers and ends near Jaisalmer, in Rajasthan. After the construction of the Indira Gandhi Canal, irrigation facilities were available over an area of 677 km² in Jaisalmer district and 37 km² in Barmer district. The canal has transformed the barren desert of this district into rich and lush fields. Crops of mustard, cotton, and wheat now flourish in this semi-arid western region replacing the sand there previously. Besides providing water for agriculture, the canal also supplies drinking water to hundreds of people in the desert areas. Map showing Thar Desert of Rajasthan along with different districts is shown in Fig.1.12 and District wise stations maps of this region are shown in Fig.1.13. Fig.1.12 Location Map of Thar Desert of Rajasthan 9

Jaisalmer Barmer Jodhpur Bikaner Fig.1.13 Stations maps of different districts of Thar Desert 1

District wise area of Thar Desert is given as follows :- S. No. District/Region Area in sq. km. % Area 1 Jaisalmer 3841 32 2 Jodhpur 2285 19 3 Barmer 28387 24 4 Bikaner 3248 25 Thar Desert of Rajasthan 119886 1 1.14 The Rajasthan desert which forms a major portion of the Thar Desert is the biggest desert in India and encompasses mainly the districts of Jaisalmer, Barmer, Bikaner and Jodhpur. In fact the Rajasthan Desert comprises the desert triangle of three cities - Jaisalmer, Bikaner and Jodhpur. This desert is spread over 119886 sq.km. (approx.) of area and is 35% of the total area of the state. Jaisamer district covers the largest (32%) and Jodhpur district the least (19%) desert area. Other two districts namely Bikaner and Barmer districts cover about 25% and 24% area, respectively. 11

CHAPTER - II ============================================================================== General Climate General climate of Thar Desert of Rajasthan is dry and hot. Mainly three seasons namely summer, rainy and winter are observed over the region. Summer season generally starts from the mid March and continues up to the end of June. May and June are the peak summer months. During summers, days are very hot and longer. Day maximum temperatures range between 45 deg. Celsius and 49 deg. Celsius on many days. However, summer nights are quite pleasant because of its soil characteristics. The ever recorded maximum temperature (49.4 deg.cel.) of this region was observed at Bikaner on 28 th May 1914. Night temperatures significantly drop as compared to the day temperatures. Heat wave and hot day conditions are observed on many occasions over this region. Strong and dust raising hot winds during afternoon hours are the common feature during peak summer period. Due to large scale heating during summer months, a low pressure area develops over the region called the heat low which prevails up to the end of monsoon season. Due to formation of strong pressure gradient and neighborhood, strong dust raising winds called ANDHIS are observed on a few occasions over this region. The effect of these ANDHIS is also observed over other parts of the state as well as the neighboring states of the country namely Haryana, Punjab, UP, Delhi and West MP. The day time visibility drops considerably during these weather events affecting the normal activities in different fields. However, these weather events bring a relief from higher day temperatures. During the summer season, days are very dry as humidity drops below 2%. At the end of summer season (June end), due to incursion of moisture from Arabian Sea, high temperatures and unstable atmosphere conditions prevail over the region. Dust storm / Thunder storm activities associated with light to moderate rainfall are a common feature during afternoon hours. On some occasions, strong winds with gale force are also observed damaging the infrastructures at many places. These activities continue till the onset of monsoon. Summer prevails for a longer duration than other seasons. 12

Monsoon generally sets over the region in the beginning of July and lasts up to the end of August. Rains are observed only for two months (July and August). Monsoon sets over Kerala coast around 1 st June and is last to reach this region (around 1st July). On the other hand, the withdrawal of monsoon commences first from this region (around 1 st September). 97% of the annual rainfall is observed during monsoon season with a highest variability in the country. The annual (251 mm) over the Thar Desert is also least in the country. The cumulative seasonal monsoon rainfall over Thar Desert during recent 56 years (1957-212) is shown in fig. 6.3.1. Generally, monsoon withdraws from the region during middle of September. Afterwards, day and night temperatures again start rising and the hot conditions prevail up to the end of October, although the weather during this period (middle of September to October) becomes comparatively hot and dry with clear sky. The day temperatures range 35 to 4 deg. Celsius. A high pressure area develops over this region in the lower troposphere and the moisture incursion from Arabian Ocean stops during this period resulting in clear sky conditions. Weather during November is quite pleasant from tourist point of view. Winter conditions start developing over the region during the beginning of November month and as a result day and night temperatures start falling slowly over the region. The peak winter conditions are observed during December and January. Winter is also very chilly over most parts of the Thar Desert. The minimum temperature even drops below freezing level on some occasions. The lowest minimum temperature of -5.9 deg. Celsius was observed at Jaisalmer on 12 th January 1967. The average minimum temperature during winter months is less than 1 deg. Celsius. Winters are also extreme over the region and generally continue up to the middle of February. After middle of February, the day and night temperatures again start rising slowly. Weather during March month becomes pleasant from the tourist point of view. Weather during November and March months over Thar Desert attracts a lot of local and international tourists for a visit to the region. Mean monthly and extreme maximum / minimum temperatures and rainfall features over different parts of the region are shown 13

in Fig. 2.1 Monthly temperatures, rainfall and rainy day patterns are almost similar over different parts of the desert. However, rainfall decreases gradually as we move westwards and thus Jaisalmer district gets the least average rainfall (159 mm) and Jodhpur district gets the highest (27 mm) during monsoon season. Fig. 2.1 Normal minimum, maximum temperatures, rainfall and rainy days of Thar Desert of Rajasthan 14

Stations Extreme Temperatures in Degree Celsius. Highest Lowest Jaisalmer 49.2 ( 4 th June 1991 ) - 5.9 ( 12 Jan. 1967) Bikaner 49.4 (28 th May1914 ) - 4. ( 26 Jan 1964) Barmer 49.1 ( 7 th June 211 ) - 1.7 ( 15 Jan. 1935 ) Jodhpur 48.9 ( 25 th May 1932 ) - 2.2 ( 31 Jan 195 ) 2.1 Data Used Daily rainfall data for the period 1957-212 (56 years) of 3 rain - gauge stations (listed below), functioning under the state Government and India Meteorological Department at station and sub station levels has been used to define the rainfall features of Thar Desert of Rajasthan. Each station is represented by at least one rain gauge station. The district rainfall of different temporal scales has been worked out as the simple average of all stations level rain gauge. The rainfall features of the whole region are based upon the area weighted average district rainfalls. S. No. Districts/Stations Jodhpur Bikaner Barmer Jaisalmer 1 Jodhpur Bikaner Barmer Jaisalmer 2 Phalodi Lunkaransar Chohtan Fatehgarh 3 Bilara Kolayat Pachpadra Pokran 4 Shergarh Nokha Sheo Ramgarh 5 Osian Chattargarh Siwana Sam 6 Bhopalgarh Dungargarh Baitu Nokh 7 Jaswant Sagar Pugal Gudamalani 8 Luni Khajuwala Ramsar 15

Fig. 2.2 Raingauge stations of Thar Desert of Rajasthan 16

1 18 35 52 69 86 13 12 137 154 171 188 25 222 239 256 273 29 37 324 341 358 1 19 37 55 73 91 19 127 145 163 181 199 217 235 253 271 289 37 325 343 361 Rainfall ( mm) Rainfall ( mm) CHAPTER- III ============================================================================== Rainfall Features 3.1 Rainfall In this chapter daily, weekly, monthly and seasonal features of rainfall over Thar Desert have been described. 3.1.1 Daily Rainfall Description Daily district wise normal rainfall is shown in Fig.3.1.1.1 which shows that rainfall is insignificant during the period from January to end of May and middle of September to end of the year. The highest daily normal value of the order of 5 to 6 mm is observed around 19 th to 215 th day of the year. The rainfall increases from beginning of July and attains its peak value around 19 th to 215 th day and then starts decreasing up to end of September. A drastic decrease in rainfall takes place after the 3 th day and there are occasional spells of rain during rest days of the year. Jaisalmer Bikaner NORMAL RAINFALL 6 5 5 4 3 2 4 3 2 1 1 Days Days 17

1 18 35 52 69 86 13 12 137 154 171 188 25 222 239 256 273 29 37 324 341 358 1 19 37 55 73 91 19 127 145 163 181 199 217 235 253 271 289 37 325 343 361 Rainfall ( mm) Rainfall ( mm) Barmer Jodhpur 7 6 6 5 5 4 3 2 1 4 3 2 1 Days Days Fig. 3.1.1.1 Daily normal rainfall over different parts of Thar Desert Daily district wise normal rainfall distribution in different range is shown in Fig.3.1.1.2 which reveals that in about 7 to 74% cases the daily rainfall occurs less than 5 mm ; in 13 to 16% cases it ranges between 5 to 1 mm and in 6 to 7 % cases it ranges between 15 to 2 mm. The daily rainfall exceeding 5 mm is rare. However, there are cases when it was observed in the range of 5 to 15 mm and even more also. Jaisalmer Bikaner <R<=5 5<R<=1 1<R<=15 15<R<=2 6.2% 3.1% 3.7%.2%.1% 6% 3% 4% 1% % % 16% 12.8% 73.8% 7% 18

Barmer Jodhpur 3.1% 3.7%.2%.1% 7% 3% 5% % % 6.2% % 14% 12.8% 73.8% 71% Fig.3.1.1.2 Daily rainfall distribution in different ranges over different districts of Thar Desert of India 3.1.2 Weekly Rainfall Description Weekly normal rainfall over Thar Desert gradually increases from 24 th week to 29 th week and then gradually decreases up to 42 nd week (Fig. 3.1.2.1). A sudden increase in weekly rainfall during 33 th and 36 th week is also observed. The highest (21 mm) rainfall is observed during 29 th week (first week of August). The weekly rainfall decreases drastically even to less than 2 mm from 4 th week (1 st week of October) onward. This trend continues up to the 2 th week (end of May). Weekly rainfall during peak monsoon season varies between 12 to 21 mm. During Monsoon season weekly rainfall attains its highest value during 5 weeks time (9 mm during 25 th week to 21 mm during 29th week) while abatement takes place in 1 weeks time (21 mm during 29 th week to 4 mm during 39 th week). District wise weekly normal rainfall over the Indian Thar Desert and its parts is shown in figure 3.1.2.1 19

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Rainfall (mm) 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Fig.3.1.2.1 Weekly normal rainfall over Thar Desert. Jaisalmer Bikaner 2 18 18 2 18 18 16 14 12 1 8 6 4 2 1 1 1111 11 1 1 1 4 2 5 4 7 8 14 13 13 14 12 11 9 8 11 6 3 21 2 1 16 14 12 1 8 6 4 2 13 13 14 12 11 11 9 7 8 8 6 5 4 4 3 1 1 1111 11 1 1 2 21 2 1 1 14 Weeks Weeks Barmer Jodhpur 3 25 2 23 2424 17 19 1919 17 17 3 25 2 23 2 26 24 23 25 23 1717 18 15 1 5 9 1 6 4 111 111 1 1 1 11 2 2 12 12 44 21 2 1 1 11 15 1 5 1 11 7 1 111111 11 12233 13 3 4 1 2 1 11 1 1 1 Weeks Weeks Fig.3.1.2.2 Weekly normal rainfall over different parts of Thar Desert of Rajasthan 2

Rainfall (mm ) 3.1.3 Monthly Rainfall Description Monthly normal rainfall distribution of Thar Desert is shown in Fig.3.1.3.1 and Fig.3.1.3.2.These figures show that the highest monthly rainfall of 8 mm (32% of annual rainfall ) is realized in July and 74 mm(29% of annual rainfall) rainfall is observed during August. The total monthly rainfall is insignificant ( less than 11 mm ) in all other months of the year except monsoon months (June to September). The monthly rainfall during June and September is 3mm and 34 mm respectively. The July and August are the main rainy months. Monthly rainfall is about 2% or less of the annual rainfall in the each month during the period from October to April. It is 4% in May. 9 8 Normal Rainfall 8 74 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 7 6 NOV 1% DEC 1% JAN 1% FEB MAR 2% 1% APR 1% MAY 4% 5 4 3 3 34 SEP 14% OCT 2% JUN 12% 2 1 2 4 4 4 1 5 2 2 Months Fig. 3.1.3.1 Monthly Normal Rainfall Thar Desert AUG 29% Fig. 3.1.3.2 JUL 32% Monthly Rainfall Distribution Thar Desert Fig. 3.1.3.1 Fig. 3.1.3.2 (Monthly normal rainfall of Thar Desert of Rajasthan) 21

Rainfall ( mm) & variability in % 3.1.4 Seasonal / Annual Rainfall Description Seasonal and annual normal rainfall distribution along with their variability (in terms of Standard Deviation & Coefficient of Variation ) is shown in Fig. 3.1.4.1 and Fig. 3.1.4.2 Total annual normal rainfall of Thar Desert is 251 mm with 38% coefficient of variation (CV). Total rainfall during post monsoon season is lowest ( 7 mm ) among all seasons. The rainfall is rather more in Summer (18 mm) and Winter (8 mm) seasons than Post monsoon. A significant increase in rainfall is observed from summer ( 18 mm ) to monsoon season ( 218 mm ). The highest (CV 184 % ) rainfall variability is observed in Post Monsoon season, while the lowest (CV 42 %) in Monsoon season. About 9% of the annual rainfall is realised during the monsoon season. The contribution of winter, summer and post monsoon season s rainfall is 3%, 4% and 3% respectively. Normal rain SD CV Winter Summer Monsoon Post monsoon 3 25 2 218 184 251 Post monsoon 3% Winter 3% 15 1 17 97 91 95 Monsoon 9% Summer 4% 5 8 8 1817 42 7 14 38 Winter Summer Monsoon Post monsoon Annual Seasons Fig. 3.1.4.1 Seasonal/ Annual Rain and Variability over Thar Desert Fig. 3.1.4.2 Seasonal Rainfall Distribution Thar Desert Fig.3.1.4.1 Fig.3.1.4.2 (Seasonal and annual normal rainfall of Thar Desert of Rajasthan) 22

6 Rainfall ( mm) & variability in % Rainfall ( mm) & variability in % 6 18 16 16 17 123 129 143 145 Rainfall ( mm) & variability in % 8 15 12 16 26 18 87 86 96 89 Rainfall in mm & variability in % The district wise seasonal, annual rainfall distribution and varibility in rainfall are shown in Fig,3.1.4.3. The lowest (182 mm) annual rainfall is observed over Jaisalmer district and the Highest (297 mm) over Jodhpur district. Bikaner (265 mm)and Barmer(267 mm) districts receive almost same order of annual rainfall. Barmer district shows larger rainfall variabilty during Summer (CV-134%), winter(cv-142%) and Monsoon (CV-59%)season in comparision to other districts of the region. But during post monsoon season,bikaner district has largest rainfall variability among all districts. 25 2 15 1 5 6 142 13 118 Normal rain SD CV 225 182 158 55 6 49 3 25 2 15 1 5 14 113 27 98 217 4 7 237 265 36 Winter Summer Monsoon Seasons Post monsoon Annual Jaisalmer Winter Summer Monsoon Seasons Post monsoon Annual Bikaner 3 25 2 15 1 5 35 267 297 241 3 271 25 177 217 153 2 134 15 123 12 59 1 54 45 44 5 14 5 13 4 9 8 Winter Summer Monsoon Post Annual Winter Summer Monsoon Post Annual monsoon monsoon Seasons Seasons Barmer Jodhpur Fig. 3.1.4.3 Seasonal / Annual Rainfall and their variability over different parts of Thar Desert 23

1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 27 28 29 21 211 212 Rainy days 3.2 Rainy Days Annual variation of rainy days is shown in Fig. 3.2.1. The annual rainy days over Thar Desert are 88 days. The lowest (53) rainy days have been observed during year 1969 while the highest (148) days during year 1979. The normal annual rainy days over Jaisalmer, Bikaner, Barmer and Jodhpur districts are 35, 48, 43 and 59 days, respectively. The lowest (15, 29, 21) rainy days were observed in Jaisalmer, Bikaner and Barmer districts during the years 1969and 22 both, respectively while Jodhpur district observed lowest (18) rainy days during the year 29. The highest (56, 74,66 & 117) rainy days were observed over Jaisalmer, Bikaner,Barmer and Jodhpur districts during the years 1961, 1997,1994 and 1979, respectively. Weekly normal rainy days are less than 1 day during the whole year except the monsoon season. During 27 th to 34 th week the normal weekly rainy days are about 2 to 3 days over Jaisalmer, Bikaner and Barmer districts while these are 3 to 4 days over Jodhpur district. On the other hand, there are instances during winter, summer and post Monsoon season when rainfall is observed on more than 5 days in a week (6 th,7 th,14 th & 5 th ) in Bikaner district and ( 13 th, 15 th, 47 th, & 51th weeks ) in Jodhpur district. Fig.3.2.2 & 3.2.3). 16 14 12 1 8 6 89 111 7272 Rainy days (Rain > ) Thar Desert Rainy days Mean 19 93 89 94 85 76 115 63 53 93 84 61 83 62 9911 148 128 117 87 13 17112 72 63 68 65 9 83 16 7 87 72 97 73 88 122 85 68 55 83 56 95 7 92 19 1193 71 111 99 86 4 2 Fig. 3.2.1 Rainy days variability over Thar Desert 24

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 No of Days No of Days 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainy days Rainy days 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainy days Rainy days 6 5 4 3 2 51 47 Jaisalmer Rainy days Mean 56 2121 46 4243 26 37 32 38 16 15 3 28 51 4949 47 4445 44 24 21 4 4 31 18 19 18 48 46 39 27 28 25 52 52 37 38 36 32 39 17 18 15 33 26 44 4 38 52 27 43 8 7 6 5 4 3 2 5 51 59 5 48 47 48 3737 35 Bikaner 69 61 4645 38 34 29 3 65 61 61 59 52 41 68 52 48 38 41 32 31 43 42 52 61 31 29 41 4 48 74 4 39 66 7 68 69 62 6 59 55 52 48 31 29 38 1 1 7 6 5 4 3 2 1 Barmer 65 65 66 64 56 57 58 61 54 54 56 54 51 52 49 5 5 5 49 49 5 49 47 47 48 4545 38 39 4 43 44 43 37 38 41 39 36 37 33 29 32 35 33 26 25 26 27 3 31 29 24 21 22 23 21 13 12 11 1 9 8 7 6 5 4 3 2 1 Jodhpur 116117 85 84 8 79 81 75 72 68 7 67 66 69 68 7 59 61 6 61 63 65 67 66 63 65 57 58 57 58 59 61 6 59 55 54 56 53 4848 45 46 47 4746 45 4242 4 39 38 3635 3231 18 Fig.3.2.2 Rainy days variability over different districts of Thar Desert 8 8 max rainy days mean rainy days 7 7 6 6 5 5 4 4 3 3 2 2 1 1 Weeks Bikaner Weeks Jaisalmer 25

1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 25 26 27 28 29 3 31 32 33 34 35 36 37 38 39 4 41 42 43 44 45 46 47 48 49 5 51 52 Average Rainfall (mm) No of Days No of Days 8 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1 Weeks Barmer Weeks Jodhpur Fig. 3.2.3 Weekly normal and maximum rainy days over different disticts of Thar Desert 3.3 Probability Distribution of Weekly Rainfall The weekly probability distributionof rainfall over Thar Desert is shown in Fig.3.3.1. The prbability of weekly rain less than 5 mm during the periods 1 st to 2 th week and 39 th to 52 nd week is even less than 25%. During peak monsoon season,the probability of weekly rain less than 5 mm is more than 75% ; between 11 and 17 mm is about 5% and more than 17mm is only 25%. 35 25% probability of rain 5% probabilty of rain 75% Probability of rain 9 % probaility of rain 3 25 2 15 1 5 Weeks Fig. 3.3.1 Weekly probability distribution of average rain over Thar Desert 26

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Weeks Year to year weekly rainfall distribtion over Thar Desert is shown in Fig. 3.3.2. Out of 52 weeks in a year, normally 27 weeks get rainfall. The distribution among weeks is: 17 weeks between.1 and 5 mm; 3 weeks between 5 and 1 mm; 2 weeks between 1 and 15 mm; 1 weeks between 15 and 2 mm; 3 weeks between 2 and 5 mm; 1 weeks between 5 and 1 mm; 6 weeks between 1 and 15 mm and 1 week between 15 to 2 mm rainfall. The average weekly rainfall in different ranges is shown in Fig.3.3.3. In about 49% cases the weekly rainfall observed is less than 5 mm. The rainfall range is 5 to 1 mm in 11% cases ; 1 to 15 mm in 7% cases ; 15 to 2 mm in 5% cases ; 2 to 5 mm in 15% cases ; 5 to 1 mm in 1% ; 1 mm to 15 mm in.5 % cases and in 15 mm to 2 mm in only.1 % cases. 7 Rain > 2 mm 1<Rain < 15 mm 2<Rain < 5 mm 15<Rain<2mm 5<Rain < 1 mm 15<Rain < 2 mm <R<=5 5<R<=1 1<R<=15 15<R<=2 2<R<=5 5<R<=1 1<R<=15 15<R<=2 6 5.5% 9.7%.1% 4 3 15.5% 5.% 2 1 7.2% 11.% 49.4% Fig. 3.3.2 Weekly Rainfall Distribution Thar Desert Fig.3.3.3 Weekly Average Rainfall Distribution in Different Range over Thar Desert Fig. 3.3.2 Fig. 3.3.3 Weekly Probability distribution of dry ( rain < 5mm ) and wet ( rain > 5 mm ) weeks under different conditions is shown in Fig. 3.3.4. It can be concluded that probability of occurance of dry weather during different weeks of winter, first half of 27

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Probability Probability summer and post monsoon seasons is more than 8%. Probability of two successive wet weeks is less than 2% during these seasons. Chances of rainy weeks gradually increases from 2% (22 nd week) to more than 9% ( 3 th week). The probability of wet week during July and August months lies between 9 to 1%. The chances of two successive wet weeks is about 6 to 8% during these two months. The probability of wet week when its preceding week is dry, is also very high ( more than 9% ) during these two months. All these prbabilitites gradually decease after 33 rd week onwards and become even less than 2% during 4 th week. 1.2 Probability of Dry Week Probability of Wet Week Probability of wet/wet week Probability of Dry/Wet Week Probability of Dry / Dry Week 1.2 Probability of Dry Week Probability of Wet Week Probability of Dry/Wet Week Probability of Wet/ Wet Week 1. 1..8.8.6.6.4.4.2.2.. Weeks Fig.3.3.4 Probabilities of Dry and Wet Weeks (Dry< 5mm) &(Wet > 5mm) Thar Desert Weeks Fig.3.3.5 Probabilities of Dry and Wet WeeksRain - (Dry< 25 mm ) & ( Wet > 25 mm ) Thar Desert 28

Rainfall in mm & variability in % 1.6 2.1 4.3 CHAPTER- IV ============================================================================ Winter Season Winter season over the Thar Desert begins from December and lasts upto the month of February. Peak winters are observed in January. Rainfall is realised over the area during passage of western isturbances over the nortern parts of Rajasthan interacting with easterly waves from south. 4.1 Monthly Rainfall Distribution Monthly rainfall distribution over the Desert area is shown in Fig.4.1.1. The lowest (1.6mm, 2% of seasonal rain) monthly rainfall is realised in December, the highest ( 4.3 mm, 53% of seasonal rain) is realised in February and about 2.1mm (27% of the seasonal rain ) in January. 2 16 196 144 162 MEAN 12 SD 8 CV% 4 17 15 3 3 7 33 HIGH LOW DEC JAN Months FEB Fig. 4.1.1 Monthly rainfall features during winter season over Thar Desert The variability of monthly rainfall during winter season is shown in Fig. 4.1.2. It can be conluded that during this season the normal rainfall is 8 mm only. During February month the total rainfall does not exceed 33mm while in December and January the total monthly rainfall does not exceed 17 mm and 15 mm respectively. The normal monthly rainfall during December, January and Febuary is 1.6 mm, 2.1 mm and 29

1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 27 28 29 21 211 212 Rainfall (mm) 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall in mm 4.3 mm respectively along with their respective variability (CV) 196%, 144% and 162%. Year to year monthly rainfall variability over the whole region is shown in Fig. 4.1.2. 35 December Rainfall January Rainfall February Rainfall 3 25 2 15 1 5 Fig.4.1.2 Monthly Rainfall Distribution Winter Season Thar Desert 4.2 Seasonal Rainfall Distribution Seasonal rainfall variability during winter season, as shown in Fig. 4.2.1 indicates that long period average ( LPA) of winter rainfall is only 8mm with Coefficient of Variation 17%. The highest rainfall ( 36 mm ) of this season was observed during the year 26 while no rainfall was observed during a number of years. No significant trend in the seasonal rainfall is observed during the study period of 56 years ( 1956-212) over this desert region. 4 35 3 25 2 15 1 5 Rainfall (mm) Linear (Rainfall (mm)) Fig. 4.2.1 Total Rainfall - Winter Season Thar Desert 3

3.6 3.9 Rainfall in mm & variability in % 1.1 CHAPTER V ======================================================================= Summer Season Practically, May and June are the main summer months over most parts of the Thar Desert. This season begins from the month of March and lasts upto end of June. The duration of this season is also of three months,but during most of the years summers extend upto the end of June. Rainfall, during this season is generally observed in the wake of thundery activities associated with dust storm during afternoon or night hours. 5.1 Monthly Rainfall Distribution Monthly rainfall distribution during Summer season is as shown in Fig. 5.1.1 which indicates that about 3.6 mm rainfall of this season is observed during March, 3.9 mm in April and 1.1 mm in May. April is the driest month of this season. The highest (216 %) rainfall variability is observed in March and the lowest (112%) in May. The monthly rainfall has not exceeded 5 mm, 36 mm and 44 mm during March, April and May months respectively. On the other hand nil rainfall has also been reported during all these months of the year. 25 2 213 176 Mean 15 1 112 S D c v 5 5 36 8 7 11 44 High MAR APR MAY Months low Fig. 5.1.1 Monthly rainfall features during summer season over Thar Desert 31

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall ( mm ) Rainfall (mm) Year to year variability of monthly rain during summer season is as shown in Fig. 5.1.2 which reveals that monthly rainfall is not significant (less than 1 mm) on most ocassions during March and April during the study period. During the year 1967, March month received about 5 mm of rainfall, which is highest monthly rainfall ever recorded in this month. During the years 1982 and 1983, both April and May months observed very good total rainfall (3 to 4 mm). 6 March Rain April Rain May Rain 9 summer rain Linear ( summer rain) 5 8 7 4 6 3 5 4 2 3 1 2 1 Fig. 5.1.2. Monthly Rainfall Distribution Summer Season Thar Desert Fig.5.1.3 Summer Seasonal Rainfall variability Thar Desert 5.2 Seasonal Rainfall Distribution Variability of the seasonal rainfall is shown in Fig. 5.1.3. It can be concluded from the figure that average summer season rainfall of Thar Desert is 18 mm with 97% of variability. The highest (77 mm) seasonal rainfall was observed during the year 1983 while the lowest (. mm) during the year 198 only. During early part of the season the rainfall is not signficant. However, during the later part rainfall increases considerably due to convective activities. During the study period of 56 years (1957-212), a slight rising trend in the seasonal rainfall is noticed over the desert area. 32

CHAPTER-VI ============================================================================== Monsoon Season This is the main rainy period in the Thar Desert. Most of the gross rainfall is observed during this season only. Generally monsoon sets over the region during the 1 st week of July and lasts upto the middle of September. Period from June to September is considered as the Monsoon season for the district. Rainfall during this season is observed on account of low pressure systems formed in the Bay of Bengal and moving from east to NW direction and oscillation of the Monsoon trough from north to south and vice versa from its normal position. On some ocassions the rainfall over the area also occurs due to low pressure area formed over north Arabian ocean and its movement towards south Rajasthan. Heavy rainfall over the region is generally realised with the interaction of western disturbances and low pressure areas moving either from Bay of Bengal or Arabian ocean over and around the region. During some years low pressure areas formed over the north Arabian sea and their movement toward South east Rajasthan also gave a very good amount of rainfall over this region. 6.1 Onset and Withdrawl of Monsoon Monsoon generally sets over the Thar Desert during first week of July and withdraws during middle of September. The year to year variability is shown in Fig. 6.1.1. 33

1972 1973 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 27 28 29 21 211 212 213 27-Jun 4-Jul 1-Jul 16-Jul 13-Jul 29-Jun 3-Jul 15-Jul 28-Jun 9-Jul 22-Jul 18-Jul 6-Jul 14-Jul 24-Jul 27-Jul 1-Jul 2-Jul 1-Jul 19-Jul 13-Jul 5-Jul 3-Jun 13-Jul 3-Jun 1-Jul 29-Jun 21-Jun 2-Jul 16-Jun 1-Jul 27-Jun 5-Jul 3-Jun Dates 18-Jul 27-Jul 15-Jul 1-Jul 3-Jul 6-Jul 2-Jul 1-Jul 7-Sep 15-Sep 12-Sep 22-Sep 19-Sep 3-Sep 11-Sep 16-Sep 15-Sep 3-Sep 3-Sep 26-Sep 21-Sep 11-Sep 17-Sep 12-Sep 12-Sep 14-Sep 1-Sep 18-Sep 17-Sep 21-Sep 16-Sep 11-Sep 12-Sep 18-Sep 7-Sep 21-Sep 13-Sep 14-Sep 26-Sep 19-Sep 24-Sep 28-Sep 25-Sep 3-Sep 29-Sep 26-Sep 27-Sep 28-Sep 24-Sep 9-Sep 19-Oct 29-Sep 9-Sep 2-Aug 31-Jul 11-Jul 21-Jun 1-Jun ONSET DATES MEAN 1 WITHDRAWAL DATES MEAN 2 Fig. 6.1.1 Onset and withdrawal dates of Monsoon over Thar Desert 6.2 Monthly Rainfall Distribution Monthly rainfall distribution during monsoon season is as shown in Fig. 6.2.1 and Fig. 6.2.2. Only 14% and 16% rainfall of this season is observed during June and September respectively. July and August are the main rainy months. Both these months receive about 7% rainfall of the season. July gets the highest (36%) while August receives about 34% rainfall of the season. The normal monthly rainfall of June, July, August and September are 3 mm, 8 mm, 74 mm and 34 mm respectively. The highest (18%) rainfall variability is noticed in the September month and the lowest (56%) in July. During the study period, the monthly rainfall has not exceeded the limit of 185 mm, 184 mm, 297 mm and 133 mm in June, July, August and September months, respectively. 34

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall ( mm) Rinfall in mm and variability in % 3 34 56 8 74 71 12 18 SEP 16% AUG 34% JUN JUL AUG SEP Fig. 6.2.1 Monthly Rainfall Distribution - Monsoon Season Thar Desert JUN 14% JUL 36% 35 3 25 2 15 1 5 31 185 184 44 52 297 37 133 JUN JUL Months AUG SEP Fig. 6.2.2 Monthly Rainfall Parameters Monsoon Season Thar Desert Mean SD C V High Low Fig. 6.2.1 Fig. 6.2.2 Variability of monthly rainfall for all the four months together and each month separately is shown in Fig. 6.2.3 to Fig 6.2.4. The highest monthly rainfall realised during June, July, August and September months is 185 mm (year 1996), 184 mm (year 1995), 297 mm (year 1973) and 133 mm (year 1992) respectively and the lowest monthly rainfall observed is. mm (year 1968),. mm (year 22), 3 mm (year 1993) and. mm (year 1968) respectively. 5 45 4 35 3 25 2 15 1 5 September Rain August Rain July Rain June Rain Fig. 6.2.3 Monthly Rainfall Distribution Monsoon Season Thar Desert 35

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall (mm) Rainfall (mm ) 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall (mm) Rainfall ( mm) 2 June Rainfall Linear (June Rainfall) 3 July Rain Linear (July Rain) 18 27 16 24 14 21 12 18 1 15 8 12 6 9 4 6 2 3 June July August Rainfall Linear (August Rainfall) September Rainfall Linear (September Rainfall) 35 3 25 2 15 1 5 2 18 16 14 12 1 8 6 4 2 August September Fig. 6.2 4 Monthly rainfall variability over Thar Desert during Monsoon Season 36

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall in mm 6.3 Seasonal Rainfall Distribution Variability of the seasonal rainfall is shown in Fig.6.3.1. The average seasonal rainfall of the Thar Desert is about 218 mm with CV 42%. The highest (425 mm) rainfall was realised during the year 1975 and the lowest (5 mm) during 22. The year 1968, 1969, 1974 and 1987 were the severe drought years and 1961, 1973, 1975 and 21 were the excess rainfall years for this region. No significant trend is noticed in the monsoon seasonal rainfall over the Thar desert region of Rajasthan during the study period of 56 years (1956-212). Monsoon Rainfall Linear (Monsoon Rainfall) 5 4 3 2 1 Fig. 6.3.1 Monsoon Rainfall ( June to September ) Thar Desert 37

1972 1973 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 27 28 29 21 211 212 Weeks 6.4 Monsoon Duration Annual duration of monsoon is shown in Fig. 6.4.1 which reveals that average duration of monsoonal rain over the district is about 1.3 weeks. However, the shortest duration of 8 weeks was observed during the years 1974, 1981, and 1986 while the longest duration of 13 weeks during the years 1977, 1999, 22, 25 and 211. However, duration of Monsoon season shows an increasing trend during the study period of 56 years (1957-212). Thus, an increase of two weeks is noticed in the duration of monsoon season during past 57 years. Monsoon Duration Linear (Monsoon Duration) 14 13 13 13 13 13 13 12 12 12 12 12 12 11 11 11 11 11 11 11 11 11 11 11 11 1 1 1 1 1 1 1 1 9 9 9 9 9 9 9 9 9 8 8 8 8 7 Fig.6.4.1 Monsoon Duration for Thar Desert 38

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 5.2 2.3 Rainfall in mm & variability in % Rinfall in mm CHAPTER -VII ============================================================================== Post Monsoon Season After withdrawal of monsoon from the Thar Desert the dry and hot weather prevails over the region in October and November. This period of two months is referred to as the Post Monsoon season. Some times, rainfall is also realised over the region during this season either due to the western disturbances moving from west to east or late withdrawal of south-west monsoon. 7.1 Monthly Rainfall Distribution Monthly rainfall parameters are shown in Fig.7.1.1 These figure reveal that about 5.2 mm of the seasonal rainfall (7.5 mm) of this season is realised during October and rest 2.3 mm during November. A large variability (of the order of 245%) in the total monthly rainfall is observed in both the months. During the study period the highest (69 mm and 29 mm) monthly rainfall has been observed in October and November months, respectively. 3 October Rain November Rain 25 2 245 246 Mean S D 8 7 6 5 15 C V 4 1 69 High Low 3 2 5 13 OCT 6 NOV 29 Months Fig.7.1.1 Monthly rainfall parameters Post Monsoon Season 1 Fig. 7.1.2 Monthly Rainfall Distribution - Post Monsoon Season Thar Desert 39

1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 27 28 29 21 211 212 Rainfall in mm A large variability is observed in the monthly rainfall of October and November. The highest (69.1mm) monthly total rainfall of this season has been observed during October 1998, while the corresponding figure for November is 29.4 mm (year 1981) Fig. 7.1.2. 7.2 Seasonal Rainfall Distribution Seasonal rainfall variability during post monsoon period is shown in Fig. 7.2.1. It shows that the average rainfall of post monsoon season over Thar Desert is only 7 mm with CV 184%. This season has a highest rainfall variability among all seasons. The highest (69 mm) rainfall was recorded during the year 1998 and the lowest (. mm) during a number of years. 8 7 6 Post monsoon rain Linear (Post monsoon rain) 69 64 5 4 3 2 1 5 2 2 7 2 3 6 2 2 31 29 25 13 5 1 7 7 8 1 1 1 6 7 1 15 2 16 13 5 2 4 7 16 1 Fig. 7.2.1 Post Monsoon Seasonal Rainfall Thar Desert 4

CHAPTER - VIII ============================================================================== Rainfall Features Annual 8.1 Thar Desert Annual rainfall variability over Thar Desert is shown in Fig. 8.1.1 and Fig. 8.1.2. It can be concluded that the average annual rainfall of Thar Desert is 251 mm with a CV of 38%. The highest (461 mm) rainfall was realised during the year 1975 and the lowest (73 mm) during 1968. The annual rainfall during 1975 was about 8% more than the long period average (251 mm). During past 56 years, annual total rainfall remained excess (rain > 19% of LPA) in 17 years, normal in 19 years (rain +19% to -19% of LPA), deficit in 16 years (rain -2% to -59% of LPA) and scanty in 3 years (rain <= -6% of LPA). Over the study period f 56 years (1956-212) the total annual rainfall over Thar Desert of Rajasthan shows an increasing trend. However, no significant cyclic behaviour is observed. An increase of about 2% has been observed during past 56 years. During past 2 years about 7% of the years have observed more than LPA annual rainfall. Year to year annual rainfall variability over Jaisalmer, Bikaner, Barmer and Jodhpur districts of Thar Desert is shown in Fig. 8.1.3 to Fig. 8.1.7, Fig 8.2.1 & Fig 8.2.2. The normal / variability (CV) / highest / lowest annual rainfall over different regions of Thar Desert are as: Jaisalmer (182mm / 49% / 391mm / 54mm), Bikaner (265mm / 36% / 518mm / 69 mm), Barmer (267 mm / 54% / 77mm / 54mm) and Jodhpur (298 mm / 44% / 681 mm / 93 mm). Highest (298 mm) and lowest (182 mm) annual normal rainfall was observed at Jodhpur and Jaisalmer districts respectively. Out of these four districts of Thar Desert, three viz. Jaisalmer, Bikaner, and Barmer districts show an increasing trend in the annual rainfall over the study period (1956-212) while Jodhpur district does not show any significant trend. Thus, extreme south west part of the Thar Desert shows an incresing trend in the annual rainfall. Among all these four districts: Barmer district shows the highest (54%) variability in the annual rainfall while lowest (36%) in Bikaner district. 41

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall (mm) Rainfall (mm) 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall (mm) Rainfall (mm) 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 Rainfall (mm) -69-73 -5-57 -38-49 -5 % Departure -16-15 -3-3 -29-12 -19-26 -31-44 -36-31 -4 2 14 55 49 39 43 43 38 3 31 44 59 55 8 74 55 Annual Rain Poly. (Annual Rain) Linear (Annual Rain) 14 % Dep Annual Rain 45 35 25 15 5 1 6 2-2 -6-1 -14-23 4-62 13 8 17-2 13-21 -9 58 26 41-8 -4 16-36 -9 27 8 18 Fig.8.1.1 Annual Rainfall variability over Thar Desert Fig.8.1.2 %Deparure of Annual Rainfall from LPA Thar Desert Annual Rain Linear (Annual Rain) Annual Rain Linear (Annual Rain) 45 55 35 45 25 15 35 25 15 5 5 Jaisalmer Bikaner Annual Rain Linear (Annual Rain) Annual Rain Linear (Annual Rain) 75 65 55 45 35 25 15 5 65 55 45 35 25 15 5. Barmer Jodhpur Fig. 8.1.3 Annual rainfall variability over different districts of Thar Desert 42

1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211-84 -81-69 -36-33 -27-27 -38-56 -2-57 -55-66 -69-3 -27-27 -34-36 -23-37 -28-29 -21-43 -46-58 -64-67 -71-1 -3-6 -28-28 -36 % Departure -8-11 -16-21 -37-32 -33-51 -34-32 -36-2 -24-18 -19-1 -4-5 2 6 22 48 55 57 76 99 99 15 95 % Departure 3 9 23 21 19 36 39 37 34 3 2 46 32 58 6 124 73 71 115 131 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 21 23 25 27 29 211-69 -74-82 -62-71 -68-76 -77-52 -56-39 -39-9 -15-3 -35-44 -55-45 -14-16 -17-14 -2-16 -13-29 -29-17 -33-28 -33-5 -56-41 -5-2 -8 % Departure -6-1 -11-7 -11-19 -25-27 -21 1 5 3 15 26 23 17 12 13 11 23 27 21 49 48 51 4 35 44 39 47 71 62 64 58 69 % Departure 61 93 114 114 16 % Dep Annual Rain % Dep Annual Rain 14 14 1 6 2-2 -6-1 -45-26 -56-35 27 56 33 45 2 18 1 6 2-2 -6-1 -26-8 4 9-72 -38 6 25 4959-34 -15 3 12 12 2 68 2 3 8 32 2836-14 -14 Jaisalmer Bikaner 22 18 14 1 6 2-2 -6-1 -14-35 -11 % Dep Annual Rain 8 13-39 -4 14-71 -31-8 168 43 8 27-3 28-5 19 14 1 6 2-2 -6-1 -14-45 -15 % Dep Annual Rain 16 49 33 46-2 -2 5 Barmer Jodhpur Fig 8.1.4 % Departure of annual rainfall from LPA over different districts of Thar Desert. 8.2 District Wise Annual Rainfall Distribution The district-wise annual normal rainfall and rainy days are shown in Fig. 8.2.1 and Fig. 8.2.2. The figures show that the annual normal rainfall of different districts of Thar Desert varies between 182 mm to 298 mm. Jodhpur district observed highest annual rainfall of the order of 298 mm while Jaisalmer district observed only 182 mm (lowest among the districts). The annual district wise rainy days vary between 35 to 59 days. The lowest (35 days) is observed in Jaisalmer district and the highest (59 days) 43

Rainfall in mm, Variability (%), Rainy days ( days) in Jodhpur district. The average annual rainy days of Thar Desert are 88 days. The annual rainfall variability within the Thar Desert fluctuates from 36% to 54%. The lowest (36%) variability was observed at Bikaner district and the highest (54%) at Barmer district. 35 3 25 2 182 265 267 298 251 Average Rain 15 C V 1 5 49 35 36 48 54 42 59 44 38 88 Rainy days Jaisalmer Bikaner Barmer Jodhpur Thar Desert Regions Fig 8.2.1 District wise annual rainfall, rainy days and variability The annual district wise rainfall distribution in different range is shown in Fig 8.2.2. Normally, annual dry days over different districts of the Desert region vary from 37 to 331 days. Highest (331) number of dry days are observed over Jaisalmer district and the lowest (37) over Jodhpur district. Daily rainfall of exceeding 15 mm over any district occurs on 6 ocassions or less in a year. Out of 35 rainy days over Jaisalmer district, 25 days observed less than 5 mm rainfall. In Jodhpur, Barmer and Bikaner districts, these figures are 42 days out of 59 ; 28 days out of 43 and 33 days out of 48 respectively. 44

> <R<=5 5<R<=1 1<R<=15 15<R<=2 2<R<=5 5<R<=1 > <R<=5 5<R<=1 1<R<=15 15<R<=2 2<R<=5 5<R<=1 16% 7% 4% 2% 2% 38% 16% 7% 4% 2% 2% 38% 84% 84% Days Days > <R<=5 5<R<=1 1<R<=15 15<R<=2 2<R<=5 5<R<=1 > <R<=5 5<R<=1 1<R<=15 15<R<=2 2<R<=5 5<R<=1 16% 7% 4% 2% 2% 38% 16% 7% 4% 2% 2% 38% 84% 84% Days Days 4 35 331 Rainy/Dry days % Days 35 3 317 3 25 2 25 2 15 15 1 5 35 25 6 2 1 1 1 5 48 33 8 4 2 3 Rain range Jaisalmer Rain range Bikaner 35 3 323 35 3 37 25 25 2 2 15 15 1 5 43 28 1 5 59 42 6 3 2 3 8 4 2 3 Rain range Barmer Rain range Jodhpur Fig. 8.2.2 Rainy days over different districts of Thar Desert 45

Rainfall( mm), Rainy days( days), CV (%) 8.3 Station wise Rainfall Distribution 8.3.1 Jaisalmer District The stations-wise annual normal rainfall and rainy days are shown in Fig. 8.3.1. It shows that the annual normal rainfall of different stations of Jaisalmer district varies between 134 mm to 23 mm. Pokran station observes the highest (23 mm) and Ramgarh station the lowest (134 mm) annual rainfall. The annual station wise rainy days within the district vary between 8 to 13 days. The highest (13 days) is observed in Pokran station and the lowest (8 days) in Ramgarh station. The rainfall variability in different stations varies from 57% to 15%. The lowest (57%) variability is observed in Jaisalmer and Nokh stations while the highest (15%) in Sam. Almost all stations are showing the same (6 to 7%) variability except the Sam, where it is quite large (15% CV). 25 Average rainfall Rainy days C Vi 2 195 176 23 18 186 15 134 15 1 57 72 59 66 57 5 11 9 13 8 9 1 Jaisalmer Fatehgarh Pokran Ramgarh Sam Nokh Fig. 8.3.1.1 Stations Average Annual rainfall rainy days and rainfall variability within Jaisalmer district 46

Rainfall( mm),rainy days (days), variability(%) 8.3.2. Jodhpur District The stations-wise annual normal rainfall and rainy days are shown in Fig. 8.3.2.1. Which shows that the annual normal rainfall of different stations of Jodhpur district varies between 215 mm to 416 mm. Bilara station observed highest annual rainfall of the order of 416 mm while Phalodi station observed only 215 mm (lowest among the stations). The annual stations wise rainy days within the district varies between 14 to 22 days. The highest (22 days) is observed in Bilara station and the lowest (14 days) in Phalodi station. The rainfall variability in different stations varies from 39% to 53%. The lowest (39%) variability is observed in Osian station while the highest (53%) in Jaswant Sagar and Shergarh. Average rainfall Rainy days variability 45 4 35 359 416 343 3 287 25 2 15 215 243 1 5 46 44 46 53 53 39 2 14 22 16 18 16 Jodhpur Phalodi Bilara Shergarh Osian Jaswant sagar Fig. 8.3.2.1 Stations Average annual rainfall, rainy days and C V within Jodhpur district 47

Rainfall( mm),rrainy days( days) &Variability(%) 8.3.3. Bikaner District The station-wise annual normal rainfall and rainy days are shown in Fig. 8.3.3.1, which shows that the annual normal rainfall of different stations of Bikaner district varies between 264 mm to 32 mm with the highest (32 mm) over Dungargarh and the lowest (264 mm) over Bikaner station. The annual station wise rainy days within the district varies between 16 to 2 days. The highest (2 days) is observed at Nokha and the lowest (16 days) at Kolayat station. The rainfall variability in different stations of district fluctuates from 38% to 56%. The lowest (38%) variability is observed at Bikaner station while the highest (56%) at Kolayat. Average rainfall Rainy days C V 35 3 264 296 268 315 32 25 2 15 1 5 53 56 45 38 17 18 16 2 19 52 Bikaner Lunkaransar Kolayat Nokha Dungargarh Stations Fig. 8.3.3.1 Average annual rainfall, rainy days and rainfall variability within Bikaner district 48

Rainfall( mm) 8.3.4 Barmer District The station-wise annual normal rainfall and rainy days are shown in Fig. 8.3.4.1. It shows that the annual normal rainfall of different stations of Barmer district varies between 221 mm to 35 mm with the highest (35 mm) at Siwana and the lowest (221 mm) at Sheo. The annual station wise rainy days within the district varies between 13 to 17 days. The highest (17 days) is observed at Siwana and the lowest (13 days) at Sheo. The rainfall variability in different stations varies from 5% to 65%. The lowest (5%) variability is observed in Sheo station while the highest (65%) in Chohtan. Average rainfall Rainy days C V 4 35 35 3 25 264 288 246 221 2 15 1 5 62 65 55 5 58 14 15 15 13 17 Barmer Chohtan Pachpadra Sheo Siwana Fig. 8.3.4.1 Stations Average Annual rainfall within Barmer district 49

Rainfall in mm CHAPTER IX ============================================================================== 9.1. Jaisalmer District Extreme Rainfall The extreme rainfall observed on different temporal scales over different stations of the Jaisalmer district is shown in Fig. 9.1.1 to Fig. 9.1.7. The highest / lowest annual rainfall of Jaisalmer, Fatehgarh, Pokran, Ramgarh, Sam and Nokh stations are (513 mm / 28 mm), (527 mm / 16 mm), (54 mm / 29 mm), (386 mm / 2 mm), (134 mm / 8 mm) and (522 mm / 13 mm) respectively. The highest (134 mm) and lowest (2 mm) annual rainfall were realized in Sam and Ramgarh stations respectively. One day highest rainfall of 24 mm on 16 August 1973 at Jaisalmer; 18 mm on 19 July 1993 at Fatehgarh; 175mm on 21 June 1996 at Pokran; 18 mm on 21 September 1988 at Ramgarh, 23 mm on 21 June 1996 at Nokh and 24 mm on 17 August 1973 at Sam. Highest annual rainfall Llowest annual rainfall 14 134 12 1 8 6 4 513 527 54 386 522 2 28 16 29 2 8 13 Jaisalmer Fatehgarh Pokran Ramgarh Sam Nokh Stations Fig. 9.1.1 Highest and lowest annual rainfall Jaisalmer district 5

24 August 1957 12 September 1958 1 July 1959 1 July 196 26 June 1961 1 July 1962 12 September 1963 18 August 1964 12 July 1965 21 June 1966 3 July 1967 7 July 1968 14 July 1969 25 September 197 3 July 1971 11 July 1972 15 August 1973 27 May 1974 29 August 1975 14 August 1976 15 June 1977 29 September 1978 4 August 1979 3 July 198 9 August 1981 17 August 1982 18 July 1983 11 August 1984 17 July 1985 8 August 1986 7 May 1987 16 July 1988 28 July 1989 6 July 199 1 August 1991 3 September 1992 19 July 1993 12 September 1994 15 July 1995 21 June 1996 8 August 1997 16 October 1998 2 August 1999 15 July 2 4 July 21 3 June 22 1 uly 23 12 August 24 2 August 25 21 August 26 23 September 27 14 August 28 15 July 29 7 June 21 11 July 211 4 September 12 13 Rainfall in mm 35 24 2633 25 25 22 33 23 2 226 22 17 25 25 57 51 45 43 63 58 54 48 48 38 37 58 7 95 83 88 118 125 165 156 18 178 24 August 1957 13 September 1958 4 July 1959 4 July 196 26 June 1961 11 August 1962 13 August 1963 3 May 1964 17 July 1965 3 August 1966 9 September 1967 7 July 1968 14 July 1969 3 July 197 23 May 1971 27 June 1972 16 August 1973 27 May 1974 22 June 1975 14 July 1976 18 June 1977 24 July 1978 4 August 1979 28 June 198 1 August 1981 24 July 1982 28 July 1983 12 August 1984 2 April 1985 8 September 1986 9 May 1987 6 August 1988 26 July 1989 11 August 199 21 June 1991 31 July 1992 19 July 1993 16 July 1994 26 July 1995 21 June 1996 19 October 1997 3 July 1998 2 August 1999 15 July 2 14 June 21 31 May 22 28 August 23 8 August 24 9 September 25 6 August 26 24 August 27 12 July 28 28 August 29 7 June 21 2 September 211 15 August 212 Rainfall in mm 25 Highest one day rain 2 24 18 189 15 135 138 1 5 57 36 3132 54 4 42 3 4733 1515 19 11 15 2 61 54 39 52 11 17 28 46 4128 4 2426 83 61 434141 75 61 48 25 21 68 61 25 85 3 76 65 28 16 85 89 65 Fig.9.1.2 Highest one day rainfall - Jaisalmer Highest one day rain 2 18 16 14 12 1 8 6 4 2 45 142 11 343 31 4854 15 24 22 42 23 447 56 75 Fig. 9.1.3 Highest one day rainfall - Fatehgarh 51

2 12 25 42 42 71 36 21 4352 44 41 32 57 14 6 65 62 16 26 31 5 25 35 36 32 4553 4 22 12 3 27 July 1957 5 July 1958 1 July 1959 1 July 196 22 June 1961 14 August 1962 13 August 1963 13 June 1964 21 May 1965 22 June 1966 23 March 1967 19 February 1968 15 August 1969 15 August 197 12 May 1971 16 April 1972 16 August 1973 27 May 1974 6 September 1975 3 September 1976 8 September 1977 12 July 1978 18 July 1979 24 July 198 23 July 1981 4 August 1982 3 September 1983 22 July 1984 17 July 1985 9 August 1986 23 June 1987 6 August 1988 28 August 1989 4 August 199 22 July 1991 4 September 1992 2 July 1993 9 July 1994 5 September 1995 24 May 1996 5 October 1997 21 September 1998 2 August 1999 22 July 2 4 July 21 1 June 22 28 August 23 2 October 24 28 July 25 28 June 26 1 February 27 2 August 28 25 July 29 1 August 21 2 September 211 6 7 7 13 1 1 23 18 26 22 25 25 34 32 Rainfall in mm 44 5 47 45 45 52 64 6 58 64 65 72 8 23 July 1957 13 September 1958 9 August 1959 1 August 196 24 June 1961 15 July 1962 3 July 1963 28 August 1964 27 August 1965 3 August 1966 29 June 1967 7 July 1968 17 August 1969 3 August 197 19 July 1971 27 June 1972 6 July 1973 27 May 1974 3 August 1975 14 July 1976 17 June 1977 27 July 1978 4 August 1979 27 July 198 11 July 1981 28 April 1982 18 July 1983 16 September 1984 13 July 1985 12 August 1986 11 June 1987 1 July 1988 25 August 1989 1 September 199 1 August 1991 3 September 1992 19 July 1993 3 July 1994 16 October 1995 21 June 1996 1 June 1997 16 October 1998 1 August 1999 16 July 2 14 June 21 1 November 22 19 June 23 8 August 24 3 June 25 11 August 26 6 July 27 6 August 28 18 June 29 7 June 21 15 August 211 6 September 212 Rainfall in mm 35 29 18 24 31 59 67 69 62 56 71 68 69 8 78 117 116 115 175 2 18 16 14 12 1 8 6 4 2 Highest one day rainfall 55 8 27 42 33 Fig.9.1.4 Highest one day rainfall - Pokran 2 18 16 14 12 1 8 6 4 2 18 37 13 51 2 6 75 26 48 35 25 37 11 1 117 18 33 54 Highest one day rainfall 31 53 18 9 15 3 25 4 66 7 Fig. 9.1.5 Highest one day rainfall - Ramgarh 52

7 49 38 32 46 25 49 18 456 3 3 28 14 32 21 48 98 6 75 35 5 26 23 43 4 17 446 21 5 45 18 335 2 54 25 18 53 1 122 157 17 November 1957 23 August 1958 1 July 1959 2 August 196 26 June 1961 9 August 1962 3 August 1963 14 August 1964 28 July 1965 23 June 1966 25 December 1967 19 February 1968 16 July 1969 26 September 197 3 July 1971 2 August 1972 17 August 1973 27 September 1974 3 September 1975 6 September 1976 29 May 1977 14 July 1978 23 October 1979 28 June 198 25 July 1981 15 August 1982 3 September 1983 12 August 1984 5 August 1985 12 August 1986 11 July 1987 3 June 1988 26 July 1989 2 September 199 24 August 1991 3 September 1992 19 July 1993 2 July 1994 28 August 1995 6 August 1996 21 June 1997 21 September 1998 2 August 1999 4 July 2 12 July 21 3 June 22 26 August 23 3 October 24 25 September 25 8 August 26 1 February 27 13 June 28 29 August 29 7 June 21 2 September 211 9 September 212 Rainfall in mm 24 August 1957 26 May 1958 1 July 1959 2 August 196 25 June 1961 13 July 1962 31 July 1963 12 July 1964 16 July 1965 9 August 1966 22 August 1967 13 July 1968 17 August 1969 24 September 197 28 June 1971 7 July 1972 17 July 1973 9 June 1974 22 July 1975 7 September 1976 26 May 1977 22 August 1978 6 August 1979 12 July 198 23 July 1981 16 August 1982 12 June 1983 3 September 1984 15 July 1985 29 May 1986 26 August 1987 1 July 1988 24 July 1989 23 August 199 1 September 1991 9 September 1992 2 July 1993 4 September 1994 27 July 1995 22 June 1996 19 October 1997 16 October 1998 23 May 1999 15 July 2 26 July 21 4 June 22 17 July 23 9 June 24 31 July 25 6 August 26 3 June 27 6 August 28 12 July 29 7 June 21 15 August 211 15 August 212 Rainfall in mm 6 5 72 76 7 115 23 25 Highest one day rainfall 2 15 1 5 58 36 6 4 45 75 Fig. 9.1.6 Highest one day rainfall - Nokh 3 Highest one day rainfall 25 24 2 15 189 168 135 16 15 1 5 35 45 33 33 58 42 51 38 19 25 18 5 85 21 3 79 39 4 55 71 77 29 24 35 5 6 66 47 5 22 2 35 45 49 16 24 3 38 2 22 26 6 39 45 28 32 24 59 2 22 Fig. 9.1.7 Highest one day rainfall - Sam 53

Rainfall in mm 9.2. Jodhpur District The extreme rainfall observed on different temporal scales over different stations of the Jodhpur district is shown in Fig. 9.2.1 to Fig. 9.2.7. The highest / lowest annual rainfall of Jodhpur, Phalodi, Bilara, Shergarh, Osian and Jaswant Sagar stations are (815 mm / 91 mm), (486 mm / 14 mm), (164 mm / 128 mm), (677 mm / 42 mm), (615 mm / 94 mm) and (188 mm / 8 mm) respectively. The highest (188 mm) and lowest (14 mm) annual rainfall were realized at Jaswant Sagar and Phalodi stations respectively. One day highest rainfall of 157 mm on 3 July 199 at Jodhpur; 168 mm on 12 July 1964 at Phalodi; 3 mm on 31 July 1999 at Bilara; 128 mm on 21July 1996 at Shergarh; 125 mm on 1 June 1998 at Osian and 273 mm on 14 September 1957 at Jaswant Sagar, was recorded. 12 164 Highest annual rainfall Llowest annual rainfall 188 1 8 6 815 486 677 615 4 2 91 14 128 42 94 8 Jodhpur Phalodi Bilara Shergarh Osian Jaswant sagar Stations Fig. 9.2.1 Highest and Lowest tehsil wise annual rainfall of Jodhpur district 54

24 August 1957 2 July 1958 6 July 1959 1 July 196 22 June 1961 15 July 1962 1 August 1963 12 July 1964 31 July 1965 4 August 1966 24 July 1967 7 July 1968 17 August 1969 1 July 197 27 August 1971 2 August 1972 7 August 1973 17 July 1974 13 July 1975 17 July 1976 18 June 1977 12 February 1978 4 August 1979 3 July 198 26 June 1981 28 April 1982 3 September 1983 21 September 1984 13 July 1985 3 May 1986 15 July 1987 1 July 1988 5 July 1989 13 June 199 25 August 1991 9 September 1992 12 September 1993 14 August 1994 16 October 1995 22 June 1996 26 August 1997 26 August 1998 1 August 1999 15 July 2 1 August 21 27 June 22 6 July 23 8 August 24 27 July 25 2 August 26 6 July 27 5 August 28 25 July 29 7 June 21 16 July 211 31 August 12 Rainfall in mm 24 August 1957 8 July 1958 28 June 1959 25 June 196 12 September 1961 13 July 1962 9 September 1963 18 August 1964 31 July 1965 4 August 1966 14 August 1967 11 July 1968 13 September 1969 11 August 197 12 August 1971 17 August 1972 13 June 1973 14 July 1974 19 July 1975 9 September 1976 28 June 1977 22 August 1978 18 July 1979 27 July 198 28 September 1981 7 May 1982 27 July 1983 12 August 1984 31 May 1985 29 July 1986 13 June 1987 16 July 1988 28 August 1989 3 July 199 22 July 1991 9 September 1992 18 July 1993 2 July 1994 27 July 1995 5 August 1996 8 August 1997 1 June 1998 1 August 1999 13 July 2 11 July 21 21 September 22 19 June 23 1 August 24 3 July 25 21 August 26 5 August 27 3 August 28 18 July 29 14 August 21 1 August 211 13 August 212 Rainfall in mm 18 16 14 12 1 8 6 4 2 Highest one day rain 157 14 146 118 122 18 96 93 97 95 74 78 84 68 74 83 88 81 78 77 77 8 82 7 61 52 56 4951 53 6 67 67 7 61 63 53 37 4 45 36 35 2829 28 39 48 3 38 42 5365 62 32 2 26 Fig. 9.2.2 Highest one day rainfall - Jodhpur 18 16 168 Highest one day rain 14 12 1 8 65 53 57 55 6 52 48 36 4 2 6 94 32 26 82 56 3836 6465 123 74 58 7 73 57 47 36 11 55 78 68 4446 5 39 15 67 25 63 56 115 33 3847 35 44 16 59 45 35 3 3 3735 19 21 15 Fig. 9.2.3 Highest one day rainfall - Phalodi 55

55.9 24 August 1957 3 September 1958 11 August 1959 1 August 196 18 July 1961 18 July 1962 27 June 1963 26 June 1964 3 July 1965 7 September 1966 3 August 1967 11 July 1968 17 July 1969 11 August 197 29 June 1971 23 August 1972 14 August 1973 2 August 1974 16 July 1975 6 August 1976 2 July 1977 28 August 1978 17 July 1979 12 July 198 22 July 1981 25 July 1982 27 July 1983 4 September 1984 16 July 1985 29 July 1986 19 August 1987 14 July 1988 27 August 1989 6 August 199 23 August 1991 5 September 1992 26 June 1993 13 August 1994 26 July 1995 18 June 1996 8 August 1997 28 August 1998 31 July 1999 22 July 2 11 July 21 23 August 22 5 July 23 1 August 24 29 July 25 26 September 26 5 July 27 5 August 28 18 July 29 8 September 21 11 August 211 14 August 212 37 41 12 23.6 16 38 28 18.4 13 25 31 23 August 1957 13 September 1958 6 July 1959 1 August 196 5 September 1961 12 September 1962 12 September 1963 2 August 1964 14 May 1965 4 August 1966 27 July 1967 7 July 1968 12 August 1969 1 July 197 27 August 1971 21 August 1972 19 August 1973 12 July 1974 1 June 1975 2 August 1976 26 July 1977 15 July 1978 19 July 1979 27 July 198 24 July 1981 22 July 1982 12 August 1983 12 August 1984 17 July 1985 12 August 1986 23 May 1987 27 July 1988 3 September 1989 6 July 199 3 August 1991 9 September 1992 4 September 1993 13 July 1994 26 July 1995 21 June 1996 8 August 1997 1 June 1998 1 August 1999 22 July 2 11 August 21 26 June 22 1 July 23 1 October 24 3 July 25 21 August 26 3 June 27 5 June 28 29 August 29 3 August 21 2 September 211 8 September 212 Rainfall in mm 2 26 25 31 37 43 47.6 44 4 5 47 64 64 6 56 66 67 76.2 88 93 93 98 123 128 37 6 63 59 63 7 53 69 68 48 53 55 49 43 47 42 42 41 42 33 43 28 35 59 59 55 Rainfall in mm 81 93 83 79 72 73 85 66 74 82 75 63 1 113 1 97 95 19 133 14 131 144 165 155 129 129 272 3 35 3 Highest one day rainfall 25 2 15 1 5 Fig. 9.2.4 Highest one day rainfall - Bilara 14 12 Highest one day rainfall 1 8 6 4 2 35.6 45.7 41.1 55.9 28.5 2.4 3.8 3 36 62.8 22.4 4352.8 18.2 43 45.6 77 5 64 4 35 53 Fig. 9.2.5 Highest one day rainfall - Shergarh 56

14 September S1957 3 September 1958 3 July 1959 2 August 196 4 September 1961 18 July 1962 29 June 1963 27 June 1964 3 July 1965 5 August 1966 26 July 1967 11 July 1968 17 August 1969 9 July 197 28 June 1971 23 August 1972 14 August 1973 14 July 1974 16 July 1975 6 August 1976 29 July 1977 3 August 1978 18 July 1979 28 June 198 22 July 1981 24 July 1982 5 August 1983 31 August 1984 16 July 1985 29 July 1986 19 August 1987 14 July 1988 17 July 1989 5 July 199 5 July 1991 11 August 1992 26 June 1993 13 August 1994 26 July 1995 22 June 1996 8 August 1997 1 June 1998 31 July 1999 22 July 2 17 July 21 26 June 22 19 June 23 13 August 24 2 July 25 3 June 26 5 July 27 5 August 28 18 July 29 1 August 21 16 July 211 14 August 212 45 41 56 52 49 5 4 35 52 43 57 49 41 Rainfall in mm 8 76 68 65 8 7 8 7 99 116 13 97 91 95 88 126 132 213 273 26 23 August 1957 12 september 1958 22 August 1959 2 August 196 26 July 1961 13 July 1962 12 August 1963 26 July 1964 31 July 1965 4 August 1966 9 September 1967 11 July 1968 18 August 1969 1 August 97 12 August 1971 21 August 1972 15 August 1973 17 July 1974 19 July 1975 9 September 1976 28 June 1977 14 August 1978 17 July 1979 3 July 198 22 July 1981 25 July 1982 28 July 1983 4 September 1984 14 July 1985 15 August 1986 23 May 1987 27 July 1988 28 August 1989 4 July 199 27 July 1991 9 September 1992 16 July 1993 1 July 1994 27 July 1995 22 June 1996 27 October 1997 1 June 1998 1 August 1999 22 July 2 24 July 21 1 September 22 28 August 23 18 June 24 31 July 25 28 June 26 6 July 27 2 August 28 25 July 29 6 August 21 16 July 211 8 September 212 Rainfall in mm 14 12 1 8 6 4 2 87 73 59 52 53 42 31 2725 114 39 7 4 47 29 525 115 13 45 93 32 73 63 43 67 86 11 38 33 36 62 83 6 4 96 32 Highest one day rainfall 828 96 58 125 95 59 55 16 98 33 68 45 4344 3 121 41 7 Fig. 9.2.6 Highest one day rainfall - Osian Highest one day rainfall 3 25 2 15 1 5 33 7 113 142 44 41 6 35 4155 6 7 94 5465 89 89 2 4 123 25 51 42 Fig. 9.2.7 Highest one day rainfall - Jaswant Sagar 57

Rainfall in mm 9.3 Bikaner District The extreme rainfall observed on different temporal scales over different stations of the Bikaner district is shown in Fig. 9.3.1 to Fig. 9.3.6. The highest / lowest annual rainfall of Bikaner, Lunkaransar, Kolayat, Nokha and Dungargarh stations are (559 mm / 32 mm), ( 783 mm / 64 mm), (894 mm / 6 mm), (769 mm / 71 m) and (94 mm / 64 mm) respectively. The highest (94 mm) and lowest (32 mm) annual rainfall were realized at Dungargarh and Bikaner respectively. One day highest rainfall of 139 mm on 29 July 211 at Bikaner; 233 mm on 24 July 2 at Lunkaransar; 138 mm on 6 August 1973 at Kolayat; 134 mm on 23 June 1996 at Nokha and 262 mm on 26 July 1983 at Dungargarh, was recorded. 1 9 8 Highest annual rainfall 783 894 Llowest annual rainfall 769 94 7 6 559 5 4 3 2 1 32 64 6 71 64 Bikaner Lunkaransar Kolayat Nokha Dungargarh Stations Fig. 9.3.1 Tehsil wise Highest and Lowest annual rainfall 58

11 2 37 34 34 31 3 29 28 37 45 47 52 38 42 69 15 July 1957 2 September 1958 1 July 1959 4 July 196 25 July 1961 18 July 1962 13 August 1963 19 August 1964 31 July 1965 4 August 1966 11 December 1967 9 July 1968 15 July 1969 19 February 197 1 September 1971 25 August 1972 12 September 1973 19 July 1974 31 August 1975 1 August 1976 24 July 1977 22 July 1978 2 July 1979 6 July 198 3 November 1981 2 August 1982 15 April 1983 16 August 1984 14 July 1985 29 July 1986 12 June 1987 25 July 1988 25 September 1989 11 August 199 2 June 1991 24 July 1992 5 September 1993 1 July 1994 16 August 1995 4 August 1996 7 December 1997 26 August 1998 2 July 1999 24 July 2 22 May 21 31 December 22 6 July 23 2 September 24 17 July 25 26 July 26 11 February 27 14 August 28 31 August 29 22 July 21 6 September 211 24 August 12 22 55 5 3 57 45 3 24 19 4 34 31 41 54 5 Rainfall in mm 58 6 77 77 67 7 65 78 72 91 98 97 1 115 19 153 233 13 August 1957 3 September 1958 16 June 1959 4 July 196 5 September 1961 21 September 1962 31 August 1963 28 August 1964 18 July 1965 9 August 1966 25 March 1967 19 August 1968 18 July 1969 25 September 197 3 June 1971 4 June 1972 17 July 1973 18 July 1974 19 July 1975 16 June 1976 17 September 1977 9 July 1978 6 September 1979 11 July 198 17 July 1981 2 August 1982 25 July 1983 16 August 1984 16 August 1985 24 June 1986 12 June 1987 1 October 1988 21 July 1989 31 May 199 22 May 1991 18 August 1992 8 July 1993 12 July 1994 28 July 1995 18 June 1996 26 August 1997 16 October 1998 12 June 1999 23 July 2 14 June 21 31 December 22 6 July 23 22 September 24 22 July 25 22 October 26 11 February 27 3 June 28 12 July 29 3 September 21 29 July 211 9 September 212 7 21 25 Rainfall in mm 42 42 4 4 5 47 47 58 6 55 55 54 57 55 48 51 56 64 64 62 58 7 71 7 76 82 88 84 8 78 86 18 127 139 16 Highest one day rain 14 12 1 8 6 4 74 78 95 2 Fig. 9.3.2 Highest one day rainfall - Bikaner 25 Highest one day rain 2 15 1 5 36 3 58 53 58 45 74 7 94 42 65 118 34 45 3 51 21 45 3 3 14 63 74 17 Fig. 9.3.3 Highest one day rainfall - Lunkaransar 59

17 43 4 4 35 25 32 26 32 44 58 68 97 13 25 2 35 34 39 5 6 54 55 52 56 53 21 35 138 15 July 1957 25 September 1958 7 July 1959 1 July 196 28 August 1961 19 July 1962 2 August 1963 5 July 1964 31 July 1965 4 August 1966 18 September 1967 11 July 1968 17 August 1969 25 September 197 21 July 1971 27 June 1972 29 August 1973 18 July 1974 19 August 1975 7 September 1976 17 September 1977 19 July 1978 26 May 1979 6 August 198 17 July 1981 28 April 1982 25 July 1983 16 August 1984 17 July 1985 2 July 1986 9 May 1987 27 July 1988 23 July 1989 12 July 199 21 July 1991 19 August 1992 15 June 1993 26 July 1994 27 August 1995 23 June 1996 3 June 1997 16 October 1998 2 July 1999 17 July 2 7 August 21 1 September 22 1 July 23 12 August 24 14 September 25 26 July 26 23 August 27 11 August 28 16 June 29 8 June 21 16 August 211 21 29 34 31 29 28 3 24 Rainfall in mm 35 46 43 41 4 56 55 52 53 61 61 67 66 64 6 71 75 71 82 8 79 85 8 12 19 134 28 June 1957 22 August 1958 2 July 1959 1 August 196 9 August 1961 21 September 1962 31 August 1963 26 July 1964 19 July 1965 4 August 1966 3 August 1967 6 July 1968 15 July 1969 23 September 197 28 June 1971 27 June 1972 6 August 1973 16 July 1974 19 August 1975 16 August 1976 17 September 1977 4 July 1978 14 October 1979 3 July 198 16 July 1981 2 August 1982 25 July 1983 21 August 1984 16 July 1985 6 August 1986 8 May 1987 3 June 1988 23 August 1989 4 August 199 24 December 1991 21 July 1992 15 June 1993 24 July 1994 24 July 1995 13 June 1996 3 June 1997 16 October 1998 2 July 1999 16 July 2 25 July 21 11 November 22 6 July 23 18 June 24 4 July 25 3 June 26 11 February 27 6 August 28 22 March 29 8 June 21 11 July 211 15 August 212 Rainfall in mm 35 75 72 73 75 7 7 67 7 75 8 8 9 88 89 1 Highest one day rainfall 16 14 12 1 8 6 4 2 43 55 65 59 72 26 19 24 55 45 62 Fig.9.3.4 Highest one day rainfall - Kolayat 16 14 Highest one day rainfall 12 1 8 6 4 34 7 81 47 55 39 56 34 48 65 79 35 27 3 83 56 61 41 9 6 67 2 Fig.9.3.5 Highest one day rainfall - Nokha 6

24 31 49 34 19 32 76 26 33 59 52 64 95 11 213 58 83 83 74 81 2 4652 74 32 41 37 39 68 2 August 1957 3 September 1958 16 June 1959 2 July 196 28 August 1961 19 July 1962 3 July 1963 12 July 1964 25 August 1965 11 May 1966 4 August 1967 11 July 1968 25 July 1969 12 August 197 29 August 1971 24 August 1972 9 August 1973 15 July 1974 17 July 1975 6 August 1976 17 September 1977 21 July 1978 25 May 1979 6 August 198 16 July 1981 2 August 1982 26 July 1983 16 September 1984 14 July 1985 16 August 1986 12 June 1987 25 July 1988 24 September 1989 3 July 199 22 May 1991 6 October 1992 26 July 1993 15 July 1994 4 August 1995 19 June 1996 4 October 1997 3 July 1998 19 July 1999 17 July 2 9 August 21 3 September 22 1 July 23 7 August 24 1 September 25 2 June 26 17 September 27 13 July 28 3 May 29 19 August 21 27 July 211 14 July 212 31 23 2 Rainfall in mm 72 64 5 59 55 58 38 36 53 48 59 42 32 76 75 115 15 149 147 141 262 3 Highest one day rainfall 25 2 15 1 5 37 46 47 Fig. 9.3.6 Highest one day rainfall - Dungargarh 9.4 Barmer District The extreme rainfall observed on different temporal scales over different stations of the Barmer district is shown in Fig. 9.4.1 to Fig. 9.4.6. The highest / lowest annual rainfall of Barmer, Chohtan, Pachpadra, Sheo and Siwana stations are (759 mm / 37 mm), (875 mm / 36 mm), (59 mm / 37 mm), (525 mm / 31 m) and (152 mm / 34 mm) respectively. The highest (152 mm) and lowest (31 mm) annual rainfall were realized at Siwana and Sheo stations respectively. One day highest rainfall of 312 mm on 8 August 199 at Barmer; 267 mm on 7 August 199 at Chohtan; 152 mm on 26 July 1995 at Pachpadra; 17 mm on 19 July 1993 at Sheo and 25 mm on 18 August 1973 at Siwana, was recorded. 61

38 92 93 Rainfall in mm 12 18 95 94 13 57 8 21 24 August 1957 26 September 1958 6 July 1959 2 July 196 26 June 1961 17 August 1962 13 September 1963 27 August 1964 3 July 1965 23 June 1966 25 March 1967 7 July 1968 12 August 1969 5 August 197 3 July 1971 21 August 1972 18 August 1973 27 May 1974 16 July 1975 14 July 1976 9 July 1977 15 July 1978 6 August 1979 21 June 198 26 September 1981 18 August 1982 1 July 1983 12 August 1984 17 July 1985 9 August 1986 15 July 1987 19 July 1988 25 August 1989 8 August 199 19 July 1991 9 September 1992 18 July 1993 2 July 1994 26 July 1995 21 June 1996 8 August 1997 1 June 1998 22 May 1999 14 August 2 9 August 21 29 June 22 29 July 23 1 August 24 22 May 25 22 August 26 2 September 27 11 July 28 24 July 29 12 November 21 31 August 211 8 September 212 28 38 25 Rainfall in mm 6 48 3 324371 43 77 128 171 312 Highest annual rainfall Llowest annual rainfall 152 1 875 8 759 6 59 525 4 2 37 36 37 31 34 Barmer Chohtan Pachpadra Sheo Siwana Stations Fig. 9.4.1 Station wise Highest and Lowest annual rainfall 35 Highest one day rain 3 25 2 15 1 5 43 98 6 54 46 71 36 59 16 25 22 69 33 29 7 43 18 64 34 4259 29 4162 22 47 152 35 84 61 86 68 Fig. 9.4.2 Highest one day rainfall - Barmer 62

24 August 1957 12 July 1958 15 June 1959 1 July 196 12 September 1961 18 July 1962 1 September 1963 8 July 1964 17 July 1965 8 September 1966 25 March 1967 28 May 1968 17 July 1969 24 September 197 26 June 1971 2 August 1972 15 August 1973 27 September 1974 7 September 1975 6 September 1976 28 July 1977 15 July 1978 18 July 1979 27 July 198 1 August 1981 6 May 1982 3 September 1983 5 September 1984 16 July 1985 29 July 1986 13 June 1987 16 July 1988 27 August 1989 6 July 199 16 July 1991 9 September 1992 18 July 1993 9 September 1994 26 July 1995 21 June 1996 8 August 1997 1 June 1998 1 August 1999 15 July 2 12 July 21 2 September 22 23 July 23 11 August 24 3 July 25 2 August 26 6 August 27 14 August 28 24 July 29 23 July 21 9 July 211 14 August 212 Rainfall in mm 21 August 1957 28 November 1958 21 August 1959 6 July 196 25 June 1961 16 August 1962 3 August 1963 12 August 1964 28 August 1965 8 September 1966 21 August 1967 1 August 1968 14 July 1969 24 September 197 3 July 1971 1 July 1972 18 August 1973 18 October 1974 3 August 1975 16 July 1976 3 June 1977 19 June 1978 4 August 1979 26 June 198 26 September 1981 18 August 1982 18 July 1983 6 August 1984 4 August 1985 31 May 1986 15 July 1987 19 July 1988 25 August 1989 7 August 199 19 July 1991 8 September 1992 19 July 1993 8 September 1994 27 August 1995 2 June 1996 28 July 1997 1 June 1998 22 May 1999 16 July 2 12 August 21 29 June 22 29 July 23 28 June 24 31 July 25 8 September 26 23 September 27 12 July 28 24 July 29 2 July 21 1 August 211 9 September 12 24 19 22 36 28 27 23 49 46 4 52 65 76 74 59 63 62 56 49 5 Rainfall in mm 72 6 62 92 12 15 15 11 115 164 267 3 22 51 9 1 4 Highest one day rain 25 55 16 2 15 5 84 59 85 1 5 87 17 74 97 5 79 46 6 14 28 55 45 77 117 Fig.9.4.3 Highest one day rainfall - Chohtan 16 14 12 1 8 6 4 2 Highest one day rainfall 152 15 145 127 99 1 13 85 95 8 79 81 79 73 73 75 58 6 63 56 57 55 6471 62 65 6364 48 44 46 5 47 552 48 41 44 4 37 32 31 25 23 1816 16 22 31 32 19 22 25 2725 2 Fig. 9.4.4 Highest one day rainfall - Pachpadra 63

32 37 56 28 38 57 41 34 36 43 15 3 13 36 23 44 35 59 57 55 27 32 32 51 7 26 45 35 55 51 52 7 76 18 78 24 August 1957 26 September 1958 3 July 1959 2 July 196 5 September 1961 12 July 1962 26 November 1963 13 August 1964 26 August 1965 4 August 1966 25 March 1967 7 July 1968 16 July 1969 2 September 197 3 July 1971 2 August 1972 18 August 1973 27 May 1974 16 July 1975 26 August 1976 28 July 1977 25 July 1978 18 June 1979 27 July 198 3 November 1981 25 July 1982 3 September 1983 12 August 1984 16 July 1985 29 July 1986 25 June 1987 4 August 1988 16 August 1989 6 July 199 22 July 1991 8 September 1992 18 July 1993 14 August 1994 26 July 1995 21 June 1996 21 June 1997 1 June 1998 1 August 1999 2 July 2 12 July 21 26 June 22 18 June 23 1 August 24 2 August 25 2 August 26 1 July 27 13 August 28 18 July 29 23 July 21 9 July 211 12 July 212 Rainfall in mm 25 August 1957 5 July 1958 19 August 1959 1 July 196 26 June 1961 11 September 1962 3 July 1963 21 August 1964 28 July 1965 3 August 1966 22 March 1967 13 March 1968 14 July 1969 3 July 197 3 July 1971 21 August 1972 17 August 1973 27 May 1974 16 July 1975 8 September 1976 11 July 1977 12 November 1978 4 August 1979 5 July 198 25 July 1981 22 July 1982 25 July 1983 5 July 1984 5 August 1985 11 August 1986 23 May 1987 18 August 1988 2 August 1989 11 August 199 24 August 1991 4 September 1992 19 July 1993 2 July 1994 26 July 1995 21 June 1996 8 August 1997 16 October 1998 21 June 1999 16 July 2 25 July 21 28 June 22 29 July 23 3 October 24 3 August 25 23 August 26 6 August 27 11 July 28 26 July 29 24 July 21 14 August 211 Rainfall in mm 8 87 93 118 13 155 17 18 16 14 12 1 8 6 4 2 32 5 41 Highest one day rainfall 69 77 67 49 6977 32 53 62 72 Fig.9.4.5 Highest one day rainfall - Sheo 25 2 15 1 5 178 5148 37 155 99 65 51 5 56 119 31 15 89 95 77 25 87 132 46 122 45 74 78 48 57 79 61 485 35 2821 196 4 98 162 7 121 92 Highest one day rainfall 18 192 19 42 97 54 122 47 4 91 62 139 48 92 49 68 Fig. 9.4.6 Highest one day rainfall - Siwana 64

Acknowledgment This work was taken up to know the rainfall structure over the most driest region (Thar Desert ) of Rajasthan state and also of the country having the highest rainfall variability in the country and thereby meet the demand of different departments of state government of Rajasthan, research scholars, print and electronic media, general public, planners and industrialists. Authors are grateful to Dr. L.S. Rathore, Director General of Meteorology, India Meteorological Department for providing all facilities to complete this work. Authors also like to thank to Shri Ashok Kumar Sharma and Shri Alok Kulshrestha, SA for collection of data, computation work and valuable assistance. Support rendered by the officers and staff of the office of Additional Director General of Meteorology (Research), Pune for designing, typesetting and printing this publication is duly acknowledged. Thanks are also due to Group Cap. Ravindra Vishen, Scientist E for his valuable suggestions. References 1. Singh, O. P., Singh, S. S., Surender Kumar, Rainfall Profile of Jaipur, Met. Monograph Hydrology No. 14/212. 2. Singh, O. P., Singh, S. S., Surender Kumar, Rainfall Profile of Udaipur, Met. Monograph Hydrology No. 15/213 3. http://waterresources.rajasthan.gov.in/, Rajasthan Government website. 4. http://en.wikipedia.org/wiki/thar_desert, Encyclopedia website. 5. http://www.mapsofindia.com/maps/rajasthan/geography-history/desert.html, Website 6. http://www.rajasthan.gov.in/districtprofile/, Rajasthan Government website. 7. http://barmer.nic.in/, Rajasthan Government website. 8. http://jaisalmer.nic.in/, Rajasthan Government website. 9. http://jodhpur.nic.in/, Rajasthan Government website. 1. http://bikaner.nic.in/, Rajasthan Government website. 65

Table-1: Seasonal Rainfall of Thar Desert (1957-212) Rainfall (mm) % Departure from LPA Jun-Sep Oct-Nov Dec-Feb Mar-May Total Jun-Sep Oct-Nov Dec-Feb Mar-May 1957 171.3 5.5 1.8 17.3 195.8 1957-21.4-26.1-77.3-1.8 1958 183.8 19.7 7. 2.5 213. 1958-15.7 165.4-1. -85.8 1959 167.. 7. 1.3 175.2 1959-23.4-1. -9.9-92.8 196 167.. 22.6 1.3 19.8 196-23.4-1. 191.7-92.8 1961 357.5 2. 2.1 12.3 373.9 1961 64. -73.2-72.8-3.2 1962 22.9.2.9 15.3 219.3 1962-7. -97.9-87.8-12.9 1963 111.2 7.1.7 7.7 126.6 1963-49. -4.5-9.9-56.4 1964 23.6. 3.7 1.1 244.5 1964 5.7-99.6-51.9-42.4 1965 162.9 2.2 11.4 8.9 185.3 1965-25.3-7.6 46.9-49.6 1966 169. 2.6. 9.3 18.9 1966-22.5-65.2-1. -47. 1967 183.6 6.3 24.3 53.5 267.6 1967-15.8-15.1 213.2 24.3 1968 64.2.4 1.8 6.4 72.8 1968-7.5-95.2-76.9-63.7 1969 88.8 1.8 2.6 3.1 114.3 1969-59.3-76. 165.9-82.3 197 256.6. 2.7 5.7 265. 197 17.7-1. -65. -67.7 1971 175.4 1.7 1.9 24. 23.1 1971-19.5-76.7-75.5 36.6 1972 149.6.2.3 3.5 153.6 1972-31.4-97.1-96.7-79.9 1973 388.5.2 1. 8.5 398.2 1973 78.1-96.8-86.7-51.6 1974 93.4 4.9.9 28.3 127.5 1974-57.2-33.7-88.2 61. 1975 425. 24.8 9.1 1.9 46.8 1975 94.9 234.4 17. -89.4 1976 344.2 12.8 8.4 8. 373.4 1976 57.9 72.6 8.4-54.7 1977 319.9.7 1.7 18.9 35.2 1977 46.7-91.2 38. 7.7 1978 24.7 1. 27.2 8. 285.8 1978 1.4 34.6 251. -54.6 1979 197. 31.3 3. 35.6 266.9 1979-9.7 321.4-61.8 12.9 198 159.8 7. 13.4 1. 19.1 198-26.7-5.6 72.5-43.1 1981 149.6 29.4 12. 16.9 27.9 1981-31.4 296.4 54.3-3.8 1982 188.2 7.1 1.6 75.9 272.9 1982-13.7-3.8-79.7 332.2 1983 34.1 7.8 3. 76.8 391.6 1983 39.5 5. -61.8 337.1 66

1984 17.2.1. 1.1 171.4 1984-21.9-98.9-1. -94. 1985 118.3.7 8.5 21.6 149.1 1985-45.8-91.2 1.1 23.1 1986 13.1.6 3.3 21.9 155.9 1986-4.4-91.5-57.5 24.5 1987 67.8. 1.5 34.7 14.1 1987-68.9-1. -8.2 97.4 1988 181.9 5.5 9.2 1.4 27. 1988-16.6-25.4 18.1-41.1 1989 216.1.4 16.8 1.5 234.7 1989 -.9-94.8 116.7-91.6 199 354.1.2 4.5 24.4 383.2 199 62.4-96.7-42.2 38.7 1991 11.9.1 14.8 17.2 134.1 1991-53.2-98.1 91.1-2. 1992 334.3 6.8 4.4 5.5 351. 1992 53.3-8.5-42.7-68.5 1993 244.6 1.3 7.8 6. 259.6 1993 12.1-83. 1.2-66.1 1994 341.7. 16.3 9.1 367.2 1994 56.7-1. 11.3-48.1 1995 28. 14.7 6.8 5.5 37. 1995 28.4 98.1-12.7-69. 1996 37.7 1.7.8 37.9 348.2 1996 41.1-77.2-89.1 115.9 1997 242.2 64.3 17.6 32.7 356.8 1997 11.1 765.9 127.6 86. 1998 236.2 69.1 9.7 1.9 325.8 1998 8.3 83.5 24.7-38.2 1999 171.5 4.7.5 44. 22.8 1999-21.3-36.1-93.8 15.7 2 231.4 2.1 1.1 5.9 24.5 2 6.1-71.3-86.4-66.6 21 247.2 12.8.9 3. 29.9 21 13.4 72.5-88.7 7.8 22 5.2 3.7 24.4 9.1 87.5 22-77. -49.9 215.2-48.3 23 35.6.5.9 3.5 31.5 23 4.2-93.5-88. -8.1 24 135.4 16. 14.7 7.2 173.3 24-37.9 115.3 9.2-59.2 25 191.5.. 23.9 215.4 25-12.2-1. -1. 35.9 26 284. 6.9 35.7 25.5 352.1 26 3.2-6.5 36.3 45. 27 21.5.2 2.3 26.8 239.7 27-3.5-97.8-7. 52.4 28 239.2. 14.3 45.9 299.4 28 9.7-1. 83.9 161.4 29 152.2.4 3.1 16. 171.7 29-3.2-94.5-6.4-8.7 21 411.3 15.6 14.8 5.1 446.7 21 88.6 19.6 91.4-71.2 211 341.7.2.4 7. 349.2 211 56.7-97.7-95. -6. 212 26.5 1.4. 23.1 285.1 212 19.5-8.6-1. 31.4 Mean 218.1 7.4 7.8 17.6 25.8 SD 9.9 13.7 8.3 17. 94.6 CV 41.7 184.4 17.2 96.6 37.7 67

District: Jodhpur Table2.1: Stations wise Annual Rainfall (in mm), Variability and District Rainfall Statistics Stations/District 1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 Jodhpur 272.4 37.1 218.2 215 354.8 28.1 259 373.2 284.9 362.6 61.8 187.2 13.7 631.8 268.5 237 651.8 Phalodi 216.7 238.2 17.9 165 316.5 365.7 154.3 346.6 21 255 215.4 98 134.2 374.3 187.7 13.8 354.3 Bilara 343.5 33.1 39.4 31 477.5 314.3 233.1 49.7 472.2 268.4 558.2 278.6 233 642.6 429.9 161 622.8 Shergarh 199.9 249.3 229.1 225 35.3 191.5 119.8 172.3 17 148.4 289.8 61.2 59.8 224.5 151.8 92.6 4.6 Osian 237 19.4 19.1 185 283.8 215.7 98.6 2.2 299.9 344 346 213 128 375.4 226.3 22.3 34.2 Jaswant Sagar 594.7 4.6 273.3 269 531.9 287.2 147.7 48.9 362.9 92 57.5 241 179 561 329 163 586 JODHPUR DIST. ( Mean AM) 31.7 281.5 231.8 226.7 378.3 275.8 168.8 332. 298.5 245.1 421.3 179.8 139.6 468.3 265.5 164.5 492.6 SD 148.2 72.8 51.7 51. 12. 63.9 63.6 123.2 11. 16.8 159.6 84.2 6.2 168.9 11.6 51. 142.7 CV% 48 26 22 22 27 23 38 37 37 44 38 47 43 36 38 31 29 MEAN(WT) 263.6 257. 29.4 24.2 343.1 288.1 153.8 37.6 255.7 248. 341. 145.9 128. 47.4 226.6 151. 429.3 DIFFERENCE 47.1 24.4 22.4 22.5 35.2-12.3 15. 24.4 42.8-3. 8.2 34. 11.6 6.8 38.9 13.4 63.3 Stations/District 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 Jodhpur 194.4 78.9 645.1 386.2 441.7 572.2 25.2 279.4 451.2 441.9 294.5 29.1 175 165 322.3 34 815 Phalodi 26.9 433.6 383 255 14.4 254 217 195 257 486 145 196.5 168 227.8 166 14 25 Bilara 315.8 156.5 76 653.9 285.5 163.9 245.1 182 48 73.1 318 279 278 21.5 442.9 341.6 628 Shergarh 42 273 445 259 382 317 235.2 97.4 249.8 355 11 182.3 64.2 77.9 274.8 229.8 43.2 Osian 298.4 615 361 348.9 269.3 258.5 34.6 24 313 378 255.2 164 173 14 269 256 346 Jaswant Sagar 14.2 188 752 16 251.1 244 24 111 232 361 263.5 268.3 217 167 377.1 379.6 45.8 JODHPUR DIST. ( Mean AM) SD CV% MEAN(WT) DIFFERENCE 193.6 695.8 557.7 334.8 274. 451.6 254.7 178.1 318.5 454.2 231. 216.5 179.2 163.2 38.7 275.2 482.2 16.8 328.1 183.4 183.9 146.9 324.7 43.6 66.7 91.3 132.2 84. 46.8 7.1 51.9 95.9 85.8 25.8 55 47 33 55 54 72 17 37 29 29 36 22 39 32 31 31 43 191. 565.1 476.5 34.8 29.7 361.9 249.2 178. 293.8 445.9 195.4 22. 162.9 171.2 259.1 228.6 395.7 2.7 13.7 81.2 3.1 64.3 89.7 5.5.1 24.7 8.3 35.7 14.5 16.3-8. 49.6 46.6 86.4 68

Stations/District 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 26 Jodhpur 232.5 526 232 396 374 521.1 572.1 577 357.5 273 527 91 359 182 283 21 Phalodi 55.5 252 178 311 143 265 287 233 156 146 251 63 221 79 111 142 Bilara 33.4 496 256 571 581 357 588 321 524 274 336 149 353 496 51 455 Shergarh 24 374 239.6 293.6 377 385 323 24 235 232 346 72.8 353 13 19 221 Osian 211 424 21 544 428 478 387 431 298 192 322 94 483 192 262 25 Jaswant Sagar 272.2 499.6 234 549 556 47 364 321.2 438 274.5 51 8 295 497 411 292 JODHPUR DIST. ( Mean AM) 213.1 428.6 223.4 444.1 49.8 42.2 42.2 353.9 334.8 231.9 382. 91.6 344. 258.2 281. 254.2 SD 86. 13.2 28.5 126.3 157.8 9.6 128.6 13.7 134.3 53.4 111. 3.4 86.3 189.7 16.1 19.4 CV% 4 24 13 28 39 23 31 37 4 23 29 33 25 73 57 43 MEAN(WT) 165.2 37.8 29.7 397. 328.1 367.7 368.7 315.2 267.7 23.1 335.2 81.3 321.2 181.3 21.2 212.2 DIFFERENCE 47.9 57.8 13.8 47.1 81.7 34.4 51.5 38.7 67.1 28.8 46.8 1.3 22.8 76.9 7.8 42. Stations/District 27 28 29 21 211 212 Mean SD CV % AREA Sq. Km. STATIONS RAINY DAYS Highest lowest Jodhpur 25 475.9 156 511 314 48 359.5 165.6 46.1 1875.52 Jodhpur 2 815 91 Phalodi 24 27 64 314 293 172 215.5 95.7 44.4 7657.65 Phalodi 14 486 14 Bilara 417 384 128 339 476 395 416.3 193.4 46.5 1653.27 Bilara 22 164 128 Shergarh 359 255 67 676.5 566 279.5 242.8 128.7 53. 3812.88 Shergarh 16 677 42 Osian 2 27.5 139 435 385 416 286.8 112.5 39.2 352.94 Osian 18 615 94 Jaswant Sagar 445 256 96 317 33 265 343.4 18.6 52.6 1653.27 Jaswant Sagar 16 188 8 JODHPUR DIST. ( Mean AM) SD CV% MEAN(WT) DIFFERENCE 35. 38.1 18.3 432.1 389.5 334.6 31.7 118.1 38. 2155.53 115.1 11.1 38.5 142.7 11.6 114.7 75.9 38 33 36 33 28 34 24 MEAN 18 27. 27.7 94. 424.2 378.4 289.3 273.4 SD 3 35. 37.4 14.3 7.9 11.1 45.3 37.3 CV % 17 69

District: Barmer Table2.2: Stations wise Annual Rainfall (in mm), Variability and District Rainfall Statistics Stations/District 1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 Barmer 182.5 192.2 258.6 255 535.6 168.2 193.6 284.4 38.7 87 235.2 37.1 63.5 163.7 157 113.8 498.9 Chohtan 137.7 156.1 23.5 2 645.4 135.6 123 365.8 126.9 87.8 334.8 39.5 36.4 154 161 165.5 492.5 Pachpadra 13.7 159.4 162.7 155 44.1 71.9 73.5 188.5 168.6 163 276.8 47.4 37 311.3 24.9 112 23.4 Sheo 145.5 146.7 21.1 197 525.1 117.2 178.5 285.3 157.4 123.9 275.2 3.8 7.5 139.8 25 199.1 429.7 Siwana 381.5 271.2 253.8 25.2 94.3 36.1 222.1 343.5 228 215 46 97 34.3 563.3 248.1 238.6 785.2 BARMER DIST. ( Mean AM) 195.6 185.1 215.9 211.4 62.9 17.6 158.1 293.5 197.9 135.3 316.4 5.4 48.3 266.4 195.2 165.8 487.3 SD 15.8 51.1 4.2 41.6 188.9 111.5 59.5 68.7 72. 54.4 87.8 26.7 17.2 179.8 37.5 54.8 198.9 CV% 54 28 19 2 31 65 38 23 36 4 28 53 36 68 19 33 41 MEAN(WT) 171. 17.8 28.8 24.4 573.4 146.3 153.6 293.4 181.6 126.2 33. 43.6 51.7 22.7 191.9 167.4 456.7 DIFFERENCE 24.6 14.3 7.1 7.1 29.5 24.3 4.5.1 16.3 9.1 13.4 6.8-3.4 45.7 3.3-1.6 3.6 Stations/District 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 Barmer 5 518.4 59.8 145.8 336.2 25.7 89 212.4 192.6 31.3 245.8 249 97.8 11.2 17.6 266.2 748.2 Chohtan 112 536.6 437 273 231 257.5 212.9 158.4 317.4 249.5 246.4 146 153 4.3 319.5 237.5 761.1 Pachpadra 79 589.6 339 23 237.4 49 144 2 232 317.7 123.3 95.4 84 128 141 148.3 428 Sheo 9 329.8 33.4 179 33 171 15 114 148.4 164 112 14 98 4 96 268.4 174 Siwana 151 743.7 284.1 423.9 39 42.6 258.7 246.4 387 446.3 224.1 174 14 11 132 34 152 BARMER DIST. ( Mean AM) 96.4 543.6 374.7 244.9 283.3 289.2 17.9 186.2 255.5 297.6 19.3 153.7 114.6 83.9 171.8 244.9 632.7 SD 37.8 148.8 95.8 11.4 46.6 11.9 65.8 51.2 96.3 13.5 67.1 62.1 3.1 41.1 86.7 58.9 338.4 CV% 39 27 26 45 16 38 39 27 38 35 35 4 26 49 5 24 53 MEAN(WT) 93.8 495.3 369.8 226.1 279.8 262.5 166.2 167.9 234.6 262.1 177.3 141.1 113. 71.8 171.8 243.3 533.8 DIFFERENCE 2.6 48.3 4.9 18.8 3.5 26.7 4.7 18.4 2.9 35.4 13.1 12.6 1.6 12.1. 1.5 98.8 7

Stations/District 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 Barmer 49 413 386 68 179 225 365 325 172 222 264 126 475 22 14 Chohtan 94.5 498.2 285 619 313 285.8 344 575 251 254 467 72 474 182 2 Pachpadra 144 43 231 43 41 216 382 339 249 225.5 236 167 56 291 266 Sheo 171 333 396 354 331 29 265 225 223 356 325 81 267 187 176 Siwana 178.4 555.6 443.1 48 274 346 543 45 288 249 271 17 69 262 223 BARMER DIST. ( Mean AM) 127.4 446. 348.2 483.8 299.6 272.6 379.8 382.8 236.6 261.3 312.6 11.6 466.2 228.4 21. SD 54.8 84.9 87.2 121.6 81.6 53.2 11.6 133.8 42.9 54.8 92.1 38.1 124.3 47.4 47.6 CV% 43 19 25 25 27 2 27 35 18 21 29 34 27 21 24 MEAN(WT) 13.9 424.2 344. 473.3 31.8 272.3 347.9 366.4 233.5 278. 328.6 13.3 424.3 216.7 197.1 DIFFERENCE -3.5 21.8 4.2 1.5-11.2.3 31.9 16.4 3.1-16.7-16. 7.3 41.9 11.7 3.9 Stations/District 26 27 28 29 21 211 212 Mean SD CV % AREA Sq. Km. STATIONS RAINY DAYS Highest lowest Barmer 759 255 27 167 433.5 343 258 263.8 163.2 61.9 2893.87 Barmer 14 759 37 Chohtan 875 181 294 24 56 65 23 288. 188.2 65.4 4692.11 Chohtan 15 875 36 Pachpadra 547 294 424 156 51 359 189 246.1 134.8 54.8 3458.27 Pachpadra 15 59 37 Sheo 478 275 191 21 428 31 216 22.7 11.3 5. 6616.32 Sheo 13 525 31 Siwana 53 288 418 21 722 35 288 349.6 22.3 57.9 245.15 Siwana 17 152 34 BARMER DIST. ( Mean AM) 632.4 258.6 36.8 194.8 528.9 384.4 23.8 273.6 142.5 52.1 1975.72 SD 175.2 45.9 111.4 33.9 12.7 125.4 41.1 49.1 CV% 28 18 36 17 23 33 18 18 MEAN 15 MEAN(WT) 628.5 254.4 282.3 2.4 53.6 393.2 221.8 26.9 SD 1 DIFFERENCE 3.9 4.2 24.5-5.6 25.3-8.8 9. 12.7 CV % 1 71

District: Bikaner Table2.3: Stations wise Annual Rainfall (in mm), Variability and District Rainfall Statistics Stations/District 1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 Bikaner 199.4 39.9 218 225 374.6 287.5 113.8 284.5 174.1 357.7 323.2 54.4 127.6 298.7 185 278.1 212.9 Lunkaransar 263.6 36.1 261.5 265 282.3 262.3 96.5 269.5 192.6 363.3 278.5 92.4 219.4 328.3 126 161.9 38.2 Kolayat 143 14.5 184.5 19 196.4 158.5 6 443.9 116.3 276 37 8.5 179 393 12.5 175 24.6 Nokha 232.9 35.2 188.1 192 334 332.6 179.2 541 154 31.5 37 157 27 35.4 425.2 227.2 359.3 Dungargarh 196.6 663.3 291.1 295 354.3 181.1 161.5 232.7 133.9 321.6 31 31 63.9 53.5 22 246.8 331.1 BIKANER DIST. ( Mean AM) 27.1 355.8 228.6 233.4 38.3 244.4 122.2 354.3 154.2 324. 315.9 138.9 159.4 374.8 215.3 217.8 29.4 SD 45.1 19.8 46.6 46. 71.4 73. 48.5 132. 3.5 37.1 34.2 12.9 64. 79.8 124.5 48.8 61.7 CV% 22 54 2 2 23 3 4 37 2 11 11 74 4 21 58 22 21 MEAN(WT) 199.5 253.9 29.9 214.8 272.1 238.1 1.4 393.6 151.8 315.7 314.3 94.1 186.6 353.8 19.2 197.7 276.1 DIFFERENCE 7.6 11.9 18.7 18.6 36.2 6.3 21.8-39.2 2.4 8.4 1.6 44.8-27.2 2.9 25.2 2.1 14.3 THESILS/DISTRICT 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 Bikaner 363.3 212 364 383.4 34.1 228.6 195.3 49 337 558.5 136.5 161.3 333 188 243 297.9 291.6 Lunkaransar 136 317 462 487.2 58 223 241 262 434 448 122 127 213 175 196 159 27 Kolayat 159.1 27.4 336 286.9 373 299.2 177.9 18.3 335 476 255 14 152 188 144 333 192 Nokha 243.1 769.4 264.6 466.5 395.6 251.4 197.5 234.1 365 61 259 134 183 145 333 342 478 Dungargarh 156.7 459 54.4 64 696 76 259 3 426 94 252 123 247 18 327 314 317 BIKANER DIST. ( Mean AM) 211.6 45.6 386.2 445.6 476.9 215.6 214.1 262.7 379.4 597.5 24.9 129.9 225.6 175.2 248.6 289.2 39.7 SD 94.2 222.9 96.8 118.7 153.9 83.6 34.2 18.9 47.8 182.1 69.3 2.8 69.6 17.8 82.2 74.7 15. CV% 45 55 25 27 32 39 16 41 13 3 34 16 31 1 33 26 34 MEAN(WT) 21. 368.6 358.6 387. 424.7 259.8 2.3 218. 366.1 55.6 23.7 124.5 21.5 176.5 28.7 285.2 281.9 DIFFERENCE 1.6 37. 27.6 58.6 52.3-44.2 13.8 44.7 13.3 91.9 1.2 5.4 24.1-1.3 39.9 4. 27.8 72

Stations/District 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 Bikaner 147.9 396 227 314 329 297 137 328 188 147 26 32 245 97 313 Lunkaransar 19 26 122 112 425 331 595 439 156 564 263 64 326 16 339 Kolayat 89 444 246 426 283 54 894 519 368 22 459 6.6 384.7 85.3 276 Nokha 79 5 267 335 242 616 541 234 351 31 27 71 392 25 224 Dungargarh 156 428.5 349 236 445 62 561 348 296 283 29 73 442 115 431 BIKANER DIST. ( Mean AM) 116.2 45.7 242.2 284.6 344.8 477.2 545.6 373.6 271.8 31.2 281.4 6.1 357.9 121.7 316.6 SD 34.5 89.7 81.7 117.8 88.2 152.2 269.7 19.1 95.6 16.5 13.6 16.5 75.4 47.9 77.2 CV% 3 22 34 41 26 32 49 29 35 53 37 27 21 39 24 MEAN(WT) 11.3 4.7 215.7 311.7 318.3 463.9 633.3 414.6 283.1 35.8 333.9 59. 349.6 115.3 287.8 DIFFERENCE 14.9 5. 26.5-27.1 26.5 13.3-87.7-41. -11.3-4.6-52.5 1.1 8.4 6.4 28.8 THESILS/DISTRICT 26 27 28 29 21 211 212 Mean SD CV % AREA Sq. Km. STATIONS RAINY DAYS Highest lowest Bikaner 277 362 254 293.5 49 356 343 263.7 1.4 38.1 384.5 Bikaner 17 559 32 Lunkaransar 27 34 545 416 783 549 558 296.3 157.3 53.1 536.6 Lunkaransar 18 783 64 Kolayat 223 324.3 334 24 386 259 419 268.2 15.3 56. 7957.6 Kolayat 16 894 6 Nokha 227 422 314 157 495 48 37 314.7 141.5 45. 383 Nokha 2 769 71 Dungargarh 22 231 369 199 417 38 193 32. 167.2 52.2 Dungargarh 19 94 64 BIKANER DIST. ( Mean AM) 227.2 335.9 363.2 253.9 498. 44.8 376.6 292.6 113.3 38.7 19882 SD 29.8 69.4 19.9 13.4 164.5 112.6 131.9 25.9 CV% 13 21 3 41 33 28 35 9 MEAN 18 MEAN(WT) 228.1 352.8 371.2 262.6 511. 389.8 433. 283.5 SD 2 DIFFERENCE -.9-17. -8. -8.7-13. 15. -56.4 9.1 CV % 9 73

District: JAISALMER Table2.4: Stations wise Annual Rainfall (in mm), Variability and District Rainfall Statistics Stations/District 1957 1958 1959 196 1961 1962 1963 1964 1965 1966 1967 1968 1969 197 1971 1972 1973 Jaisalmer 22.1 21.1 67 134.1 34.3 197.9 3.1 67.1 118 4.4 15.4 74.4 28 241.6 82.1 64.9 311.6 Fatehgarh 242.9 187.4 156.1 156.1 46.1 124 16.2 97 4.8 24 1.5 74.4 28.2 125 89.2 148 332 Pokran 229.5 13.1 154 154 287.5 19.8 84.8 153.4 218.3 21.7 152.6 38 29 19.2 154.4 88.6 141.4 Ramgarh 83.8 72.5 45.4 45.4 299.8 92.3 1.3 184.2 86.5 96 165 13 2 121.5 154 27 244.1 Sam 176.3 125 87.1 87.1 633.5 27.9 82.6 133.1 89.5 76.6 9.7 3 8 331.3 295.8 4.8 134 Nokh 2.6 195.1 135 135 224.7 144.6 13.4 199.4 14 148 119 45 7 216 214 56.4 18.6 JAISALMER DIST. ( Mean AM) 189.2 153.4 17.4 118.6 365.3 17.1 54.6 139. 115.5 99.3 129.7 45.8 27.5 24.3 164.9 71. 47. SD 56.7 52.9 47.3 43.6 144.5 63.5 38.9 5.7 6.5 69.9 3.6 24.6 23.8 78.7 8.4 43.2 448.4 CV% 3 35 44 37 4 37 71 36 52 7 24 54 87 39 49 61 11 MEAN(WT) 213.5 187.7 98.7 141.5 334.7 187.8 42.1 91.9 134.1 8.8 145.3 65.4 28.3 215.6 1.8 8.2 271.7 DIFFERENCE -24.3-34.3 8.8-22.9 3.6-17.7 12.5 47.1-18.6 18.5-15.6-19.6 -.7-11.4 64.1-9.2 135.2 THESILS/DISTRICT 1974 1975 1976 1977 1978 1979 198 1981 1982 1983 1984 1985 1986 1987 1988 1989 199 Jaisalmer 93.1 478 345 181 276.1 288.7 17.5 319.2 221.3 337.3 16.4 115.4 65 39 231.5 182 133 Fatehgarh 45 139 34 143.4 146 98 15 23 83 67 69 22 65 3 83 73 23 Pokran 62 339.5 363 23.5 138 178 27.5 18.9 135 434 171 175.5 12 13.5 179.5 18 118 Ramgarh 33.8 24.6 173 247 235 128 75 127 72 136 66 6 125 15 42 259.4 246.5 Sam 71 44 23 123 165 166 142.5 5 134 246 142 22 131.5 5 18 215.2 192 Nokh 94 142 275 189 18 162 148 21 167 335 88 94 167.3 74 82 99 14 JAISALMER DIST. ( Mean AM) 66.5 296.5 283.2 181.2 178. 17.1 148.9 138.2 135.4 259.2 116.1 81.5 19.3 56.4 133. 156.1 172.1 SD 24.6 146.4 8.1 44.1 64.1 65.1 43.4 18.4 55. 137.6 47.3 59.5 4.2 41.4 74.1 73.9 49.7 CV% 37 49 28 24 36 38 29 78 41 53 41 73 37 73 56 47 29 MEAN(WT) 79.9 45.2 348.9 182.3 227.1 239.6 177.3 233.5 184.2 33.6 152.7 119.7 74.2 6.7 21.8 151.3 137.2 DIFFERENCE -13.5-18.7-65.7-1.2-49.1-69.5-28.4-95.3-48.8-71.4-36.6-38.2 35.1-4.2-68.8 4.8 34.9 74

THESILS/DISTRICT 1991 1992 1993 1994 1995 1996 1997 1998 1999 2 21 22 23 24 25 Jaisalmer 127.8 227.3 37.7 196 32.5 19 185 333 248 145 321 63 178 47.3 22.5 Fatehgarh 81 15.5 274 287.7 234.2 211 187 318 233 368 333 44.5 324 148 19 Pokran 84 116.5 147.5 459 237 433 211.5 328 267 28 294.3 48.5 194 85 154 Ramgarh 36 154 154 326.6 162.2 116.8 23 273 182 34 121 9 212 29 57 Sam 63 326 177.5 212 233 116 246 24.1 373 78 79 51 163 77 114 Nokh 97 453.4 268 228 269 522 282.5 336 28.9 279 155 48 29 91 275 JAISALMER DIST. ( Mean AM) 81.5 23.5 232. 284.9 242.7 264.8 223.7 298.7 252. 185.3 217.2 44. 213.3 79.6 168.4 SD 31. 136.6 87.7 98.5 51.8 171.5 37.4 51.8 66.3 125.5 111.7 18.3 57.3 41.1 77.6 CV% 38 59 38 35 21 65 17 17 26 68 51 42 27 52 46 MEAN(WT) 111.6 186. 34.4 271.6 29. 252.6 191.8 33.1 251. 185.9 315.7 57.3 198.5 68.1 2.6 DIFFERENCE -3.2 44.4-72.5 13.3-47.4 12.2 31.9-31.4 1. -.6-98.5-13.3 14.8 11.5-32.1 THESILS/DISTRICT 26 27 28 29 21 211 212 Mean SD CV % AREA Sq. Km. STATIONS RAINY DAYS Highest lowest Jaisalmer 512.8 195.2 173.5 91 39 277 219 195.5 112. 57.3 24519 Jaisalmer 11 513 28 Fatehgarh 527 187 342 97 396 493 335 175.8 127.3 72.4 4352.3 Fatehgarh 9 527 16 Pokran 141 41 423 84 54 487 259 22.9 12.6 59.4 9516.8 Pokran 13 54 29 Ramgarh 157 178 139 1 386 162 183 134.2 88.3 65.8 Ramgarh 8 386 2 Sam 256 184.2 88 64.5 226.5 14 131.5 18.4 189.5 15. Sam 9 134 8 Nokh 59 385 181 175 395 326 263 186.4 15.9 56.8 Nokh 1 522 13 JAISALMER DIST. ( Mean AM) 275.5 255.1 224.4 11.9 375.4 38.2 231.8 179.2 88.9 49.6 38389 SD 199.5 17.1 129.3 38. 14.5 161.5 7.7 24.2 CV% 72 42 58 37 28 52 3 13 MEAN 1 MEAN(WT) 422.2 245.3 254.5 89.9 376.1 353.5 242.1 195.1 SD 2 DIFFERENCE -146.8 9.8-3. 12. -.7-45.4-1.3-15.9 CV % 18 75