Temperature Data. Daily Temperature. Daily Temperature Range? Daily Average Temperature? High 90 F Low 60 F. Difference between High & Low for Day

Transcription

1 TEMPERATURE

2 Temperature Data Daily Temperature High 90 F Low 60 F Daily Temperature Range? Difference between High & Low for Day Daily Average Temperature? Mid-point between High & Low for Day

3 Temperature Data Monthly Temperature Average of all Daily Temperatures in a Month Annual Temperature Annual Temperature Range? Difference between Hottest & Coldest Month Annual Mean Temperature? Average of all 12 Monthly Temperatures

4 Isotherm Map Isotherm = Equal Temperature Line that connects same temperature

5 Temperature Gradient Isotherm distance Close = Rapid change Wide = Gradual Change

6 Controls of Temperature Latitude Land & Water contrast Ocean Current circulation Altitude Geographic Position Cloud Cover & Albedo

7 Latitude Latitude most affects Temp. Solar Radiation Annual Temp. Range Greater in Higher Latitudes

8 Latitude Solar Radiation Low Sun Angles in High Latitudes Lower Temperature

9 Latitude Solar Radiation High Sun Angles in Low Latitudes Higher Temperature

10 Land & Water Contrasts Land surface Heats & Cools Faster to greater extremes to lesser depth Ocean Heats & Cools Slower Ocean Circulates (Fluid) Distributes Heat Evaporation Cooling

11 Land & Water Contrasts Differential Heating = Specific Heat Water absorbs more Energy without Heating Land Heats more with less Energy

12 Land & Water Contrasts Heating Characteristics Interior Locations Extreme Temp. Coastal Locations Moderate Temp. San Diego & Dallas are same Latitude Why different Temp.?

13 Land & Water Contrasts Same Latitude in Canada Vancouver Marine Winnipeg Continental 5 F warmer in Summer 36 F colder in Winter

14 Land & Water Contrasts Northern Hemisphere Land Hemisphere Greater Temp. range More Continental climate Southern Hemisphere Water Hemisphere Less Temp. range More Marine climate

15 Ocean Currents Atmospheric Circulation 75% of Heat Transfer Oceanic Circulation Winds propel Currents

16 Ocean Currents Currents & Wind transfer heat Equalizes Latitudinal energy imbalance

17 Wind & Ocean Currents Northern Hemisphere Clockwise Southern Hemisphere Counter-Clockwise

18 Ocean Currents Equatorial current... Warm Flows West Warm currents West Cold currents East

19 Ocean Currents Similar Latitude in South America Rio de Janeiro Warm current Arica, Chile Cold current 10 F difference throughout year

20 Altitude Vertical Temperature (Troposphere) Temperature Cools with Altitude Normal Lapse Rate 3.6 F / 1,000

21 Altitude Near Equator in South America (Ecuador) Guayaquil Sea Level Quito 9, F difference throughout year

22 Geographical Position Coastal Location relative to Winds Windward coast Temperature moderated by ocean air Leeward coast Greater Temperature range Greater heating and cooling

23 Windward & Leeward Coasts Same Latitude in U.S.A. Eureka, CA Windward Coast New York City Leeward Coast 34 F greater Temp. Range Summer & Winter

24 Topographical Barrier Topographical Barrier (Mountains) Windward slope Marine Temperature moderated Leeward slope Continental Greater Temperature range West East

25 Topographical Barrier Same Latitude in Washington Separated by Cascade Range Seattle Windward side Spokane Leeward side 20 F Greater Temp. Range

26 Cloud Cover & Albedo Clouds have High Albedo Daytime Reflects Solar Radiation Cooler Air below Night Retains Earth Radiation Reduces Temp. Loss Reduces Temperature Range Daily Temp. Cycle Monthly Temp. Cycle

27 Cloud Cover & Albedo Daily Temperature Range Clear Greater Temp. Range Overcast Less Temp. Range

28 Cloud Cover & Albedo Monsoon Cloud cover lowers summer heat Highest Temp. Dryer month prior to rains

29 Temperature Cycles When warmest & coldest during Day Year Due to Net Heat Balance between Solar Radiation Earth Radiation Lag from Peak & Low for Solar Radiation

30 Daily Net Radiation If Solar Radiation > Earth Radiation Earth Warms up during Daytime Earth then Warms the Air Warmest Time of Day?

31 Daily Net Radiation If Earth Radiation > Solar Radiation Earth Cools off during Nighttime Air Cools off Coolest Time of Day?

32 Daily Temperature Cycle Warmest time of day 2 to 5 pm Coldest time of day Sunrise

33 Daily Temperature Cycle

34 Daily Temperature Cycle Influenced by Land/Water Location Inland Temp. Large Temp. Range Riverside (Oct. 9) High = 83 F Low = 58 F Range =? Coastal Temp. Small Temp. Range Santa Monica (Oct. 9) High = 73 F Low = 60 F Range =?

35 Daily Temperature Cycle Record Daily Range in Inland Desert Record: 126 F in Day 26 F at Night

36 Annual Temperature Cycle Warmest & Coldest months differ from Summer & Winter Solstices Warmest = July-August Coldest = January-February Lag due to Net Heat Balance between Solar Radiation Earth Radiation

37 Annual Temperature Cycle Influenced by Land/Water Location Inland Rapid Heating & Cooling Hottest Month? After Summer Solstice July Coldest Month? After Winter Solstice January Coastal Slower Heating & Cooling Hottest Month? August Coldest Month? February

38 Annual Temperature Range Difference between Hottest Month Coldest Month Influenced by Latitude Proximity to Coast

39 Annual Temperature Range Largest in High Latitude & Inland Yakutsk, Siberia 68 F in July 45 F in January Range? = 113

40 Annual Temperature Range Smallest in Low Latitude & Coastal Manaus, Brazil 79 F in July 82 F in January Range?

41 Temperature Sea Level Map is most affected by Latitude Decreases from Equator to Poles More extreme in Continental interiors

42 Temperature Sea Level January Shifts South from Equator 90 Sun Angle at 23½ S Northern Hemisphere Colder inland

43 Temperature Sea Level July Shifts North from Equator 90 Sun Angle at 23½ N Northern Hemisphere Hotter inland

44 Annual Temperature Range Largest Range No. Hemisphere > 110 F in Siberia Smallest Range Along Equator < 5 F

45 Annual Temperature Range No. Hemisphere More Land Inland extremes So. Hemisphere More Ocean Moderated

46 Seasonal Latitudinal Shift Seasonal Migration of 60 F Isotherm Shifts most over continents Summer North Winter South

47 Record Temperatures High = 136 F in Libya Low = 130 F in Antarctica Annual Range = 113 F in Siberia

48 Measuring Temperature Mechanical Thermometers Temperature Change Water Maximum Temperature Mercury Minimum Temperature Alcohol (Horizontal)

49 Measuring Temperature Mechanical Thermometer Bimetal strip Thermograph Electrical Thermometer Thermal Resistor Thermistor Used in airborne Radiosondes

50 Measuring Temperature Instrument Shelter Thermometer inside White Box Provides Shade Vents 4 Above Ground Over Grassy area

51 Temperature Scales Fahrenheit Scale Freezing = 32 F Boiling = 212 F Celsius Scale 100 between Freezing = 0 C Boiling = 100 C Kelvin Scale Measures from Absolute Zero Lowest possible Temperature 273 C (= 0 Kelvin)

52 Temperature Applications Degree-Days Energy demand/consumption Heating Below 65 F Cooling Above 65 F Growing Crops Difference between Daily Mean Temperature Base Temperature of Crop Determines Harvest date

53 Temperature & Comfort Affects Human comfort Sunshine Humidity Heat Index Wind Chill Feels colder during Winter

54 Urban Heat Islands Cities Higher Temp. than in rural areas Buildings... Absorb heat Heating& AC