Climate Change and its possible impact on Egypt

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1 Climate Change and its possible impact on Egypt Prepared by Dr. Samir Riad Prof. Emeritus, Geology Department Assiut University November 1, 2010

2 Global Warming Causes &Consequences 2

3 Greenhouse Effect Is a Natural Phenomena If there were no natural greenhouse effect, the average surface temperature would have been about 34 C colder than it is today (about -20 C). The average surface temperature is 14 C. Sea Level Rise These times of increased or decreased solar radiation directly influence the Earth's climate system, thus impacting the advance and retreat of Earth's glaciers. Causes Mostly Natural Global Warming Geologic Time and Glacial Cycles Plate Tectonics Milankovitch Cycles Antarctica movement is affecting global cooling Earth's eccentricity 100,000 years Axial Tilt 41,000 years Precession 23,000 years Climate Changes thermal expansion of the water melting of the polar ice caps. Subsidence - at a rate of 3-5 mm per year in case of the Nile Delta.

4 On average, absorbed radiation from the Sun is balanced by the amount of energy returned to space in the form of infrared "heat" radiation. Greenhouse gases such as water vapor and carbon dioxide, as well as clouds and small particles trap some heat in the lower part of the Earth's atmosphere. This is called the Greenhouse Effect.

5 The greenhouse effect is a necessary phenomenon that keeps all Earth's heat from escaping to the outer atmosphere. Without the greenhouse effect, temperatures on Earth would have been much lower than they are now, and the existence of life on this planet would not be possible. However, too many greenhouse gases in Earth's atmosphere could increase the greenhouse effect. 5

6 If there were no natural greenhouse effect, the average surface temperature would been about 34 C colder than it is today (about 20 C). The Average surface temperature is 14 C.

7 The Earth's glaciers oscillate on all time scales ranges from decades to hundreds of thousands of years. These glacial pulsations are due to Earth's changing climate in relation to spatial variability (Glaciers With Space and time). With respect to time, glaciers are influenced by two major processes, Plate Tectonics and the Milankovitch Cycles, and numerous minor processes. 7

8 glaciers are influenced by Plate Tectonics process

9 In the last 65 million years (the Cenozoic Era), significant global cooling has occurred. This cooling accelerated in the last 20 million years, and the Earth's climate became more variable, in addition to being cooler. It is suspected that Antarctica moving over the South Pole initiated cooling, and that the growth of the Antarctic Ice Sheet provided positive feedback, further intensifying global cooling.

10 Recent Glaciations The current glaciations began at least 1.5 million years B.P (before present) in the Northern Hemisphere, and continues. The Pleistocene was not continually dominated by glacial times. Lengthy interglacial periods (times of little or no ice cover, other than on Antarctica) occurred during the Pleistocene. The present interglaciation (often termed the Holocene) has lasted about 10,000 years. Prior to that, climates were glacial for about 60,000 years, with two major glacial stades about 25,000 and 70,000 years ago separated by an interstade. 10

11 glaciers are influenced by Milankovitch Cycles

12 Milankovitch Cycles and Glaciations The episodic nature of the Earth's glacial and interglacial periods within the present Ice Age (the last couple of million years) have been caused primarily by cyclical changes in the Earth's circumnavigation of the Sun. Variations in the Earth's eccentricity (cycle of about 100,000 years), Axial tilt (occur on a periodicity of 41,000 years), and Precession (has a periodicity of 23,000 years) comprise the three dominant cycles, collectively known as the Milankovitch Cycles. 12

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16 Variations in these three cycles creates alterations in the seasonality of solar radiation reaching the Earth's surface. These times of increased or decreased solar radiation directly influence the Earth's climate system, thus impacting the advance and retreat of Earth's glaciers. The three Milankovitch Cycles impact the seasonality and location of solar energy around the Earth, thus impacting contrasts between the seasons.

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19 Climate change impacts Evaporation will increase as the climate warms, which will increase average global precipitation. Soil moisture is likely to decline in many regions, and intense rainstorms are likely to become more frequent. Sea level is likely to rise two feet along most of the coastal areas allover the world. Calculations of climate change for specific areas are much less reliable than global ones, and it is unclear whether regional climate will become more variable. 19

20 Climate change Impacts on nature. The Natural Environment has often adapted to climate changes that have occurred gradually over many thousands of years. Instances in which changes have occurred rapidly, brought about by events such as sudden shifts in ocean currents, these rapid changes have often caused widespread species extinctions and the collapse of natural ecosystems. 20

21 Examples of how large and rapid climate change might affect the natural environment. Plant migration: Climate may change faster than plants can move from one region to another. This may cause species extinction, lower biodiversity, and changes in the way species interact. Coral reefs: Slightly warmer tropical water may kill the algae which reef animals use for food. Changes in insect pests: Climate change can affect the number and kinds of pests directly. It can also affect them by changing the mix of plant varieties and their nutrient content. This can influence plant survival, food chains, and the spread of disease. Mangrove swamps: Mangrove swamps are important breeding grounds for many animals that live in water. Increased ocean flooding may damage these areas by changing the supply of nutrients and the amount of salt. 21

22 Climate change Impact Impacts on people. The effects of climate change on people would change from place-to-place. Economically developed societies could use technology to reduce direct impacts. For example, they might develop new crop varieties, construct new water systems, and limit coastal development. Some northern countries, such as Canada and Russia, might even benefit from longer growing seasons and lower heating bills if the climate becomes warmer. 22

23 In contrast, economically less developed societies, like those in parts of Africa, Asia, and South America depend much more directly on climate, and could be hit much harder by sudden or large changes.

24 Places like coastal Bangladesh and low lying islands, could be flooded by storms or rising sea level. Droughts in Africa might become more serious. Developing countries have far fewer resources for adapting to such changes. They may not be able to afford large projects such as sea walls or aqueducts. Farmers may have difficulty adopting new agricultural practices. The resulting social tensions could lead to more political unrest, large scale migrations, and serious international problems such as terrorism and wars. 24

25 Climate and Health Climate can have a profound influence on human health both directly and indirectly. Some direct effects include deaths and illnesses related to excessive heat or cold exposure. Indirect effects of climate on health may involve respiratory disorders due to air pollution, including spores and pollens. Incidences of waterborne diseases, such as cholera, as well as food productivity and its relation to nutrition are other indirect effects of climate on health.

26 Human health is also indirectly affected by climate due to its influence on the abundance and geographic distribution of disease vectors, such as mosquitoes and rodents. Several studies suggest projected climate changes may result in expanded geographic ranges for many mosquito borne diseases. 26

27 Projections indicate that the zone of potential malaria transmission, in response to global surface temperature increases at the top of the projected range, may enlarge from an area containing about 45% of the world population to about 60% by the end of the twenty first century, resulting in million additional cases of malaria per year 27

28 Sea Level Rise It is estimated that most of the sea level rise is a result of thermal expansion of the water of the oceans and seas as well as the melting of the polar ice caps.

29 Recorded sea Level rise between 1993 and 2007, by cause. Source: Josh Willis, NASA JP 29

30 How much warming will there be? If things go on pretty much as they have been, scientists' best guess is that the amount of warming will be about 2.5 F (1.4 C) by the year Scientists expect that the average global surface temperature could rise C in the next fifty years, and C in the next century, with significant regional variation. 30

31 IPCC scientific assessment of climate change estimated that the globally averaged surface temperature will increase by 1 to 3.5 C (about 2 to 6 F) by the year 2100, with an associated rise in sea level of 15 to 95 cm (about 6 to 37 inches). 31

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33 With sea levels already rising by the 17 cm over the last century, the impacts of such rise is becoming more and more pressing, especially that 400 million people live within 20 km of a coast. 33

34 Under the 1 m sea level rise scenario, about 41,500 km2 of the territory of the Arab countries would be directly impacted by the rise of the sea level. Projected increases in sea levels will displace a quickly growing population into more concentrated areas. At least 37 million people (~11%) will be directly affected by Sea level rise of 1 meter. 34

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36 Relative vulnerability of coastal deltas as shown by the indicative population potentially displaced by current sea level trends to 2050 (Extreme = > 1 million; High = 1 million to 50,000; Medium = 50,000 to 5,000 36

37 In the case of 2m, 3m and 4m sea level rise scenarios, around 60,000, 80,700 and 100,800 km2, respectively, of the Arab coastal region will be seriously impacted. In the extreme case of 5 m sea level rise, such impact will be at its highest, as it is estimated that up to 113,000 km2 (0.8%) of the coastal territory would be inundated by sea water.

38 Egypt, Saudi Arabia, Algeria and Morocco, will be the most affected while others such as Sudan, Syria, and Jordan will be less affected. Egypt will be by far the most impacted country of the Arab world with at least 12 million Egyptians displaced in the extreme (5 meter sea level rise) scenario. It estimates that one third of the Arab population impacted will be from Egypt alone. 38

39 Extreme scenario (5 meter sea level rise) impacts on the Arab world, by total population affected. Source: AFED Arab Environment Climate Change Report. 39

40 United Arab Emirates (UAE), Qatar and Bahrain will witness the highest Sea level rise effect in terms of the percentage of population at risk from the total country population, with 50% of the population of each country impacted by the extreme (5meter sea level rise) scenario. Qatar, the UAE, Kuwait, and Tunisia are most vulnerable in terms of their land mass, since 1 to 3 % of land in these countries will be affected by a 1 meter of sea level rise. In the most extreme case, Bahrain and Qatar would experience a significant reduction of about 13.4 % and 6.9%, respectively, of their land as a result of the 5 meter scenario. 40

41 Extreme scenario (5 meter sea level rise) impacts on the Arab world, by percentage of population affected. Source: AFED Arab Environment Climate Change Report. 41

42 Focusing on the Nile Delta, the low lying delta is already retreating at an alarming rate of about 100m per year. The retreat of the Nile Delta, which is about 24,900 km2 in area and alone accounts for about 65% of Egypt agricultural land, is not only due to climate change and sea level rise but also a result of the human activity reducing soil sediments due to the Aswan High Dam and heavy groundwater extraction. 42

43 It is expected that a sea level rise of only 1 meter would flood much of the Nile Delta, inundating about one third (~34%) of its land, placing important coastal cities such as Alexandria, Idku, Damietta and Port Said at a great risk. In this case, it is estimated that about 8.5 % of Egypt s population (~7 million people) will be displaced.

44 More alarmingly, In the extreme case of 5 meter sea level rise, more than half (~58%) of the Nile Delta will be facing destructive impacts, which would threaten at least 10 major cities (among them Alexandria, Damanhur, Kafr El Sheikh, Damietta, Mansura and Port Said), flooding productive agricultural lands, forcing about 14% of the country s population (~11.5 million people) into more concentrated areas to the southern region of the Nile Delta

45 Impact of sea level rise on the Nile Delta according to the 5 scenarios of 1 meter to 5 meter sea level rise. Source: AFED Arab Environment Climate Change Report. 45

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50 Egypt s economy will be the most vulnerable with 1 meter of sea level rise putting more than 6% of its Gross Domestic Product at risk. This figure rises to more than 12% for a sea level rise of 3 meters. More than 12% of Egypt s best agricultural lands in the Nile Delta are at risk from sea levels rise of 1 meter, and this figure rises dramatically to 25% for 3 meters and even almost 35% in the case of 5 meters. 50

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52 According to a report produced for the Organization for Economic Development, the Nile Delta is already subsiding at a rate of 3-5 mm per year. Just a.25-meter rise in sea level would devastate the populous cities that drive Egypt s economy. 40% of Egyptian industry is located in Alexandria alone; a.25-meter rise in sea level would put 60% of Alexandria s population of 4 million below sea level, as well as 56.1% of Alexandria s industrial sector. 52

53 A rise of.5 meters would be even more disastrous, placing 67% of the population, 65.9% of the industrial sector, and 75.9% of the service sector below sea level. Thirty percent of the city s area would be destroyed, 1.5 million people would have to be evacuated, and over 195,000 jobs would be lost.

54 Alexandria is not the only Egyptian city that would be devastated by even a.5- meter rise in sea level. A.5-meter rise would cost over 2 billion dollars and eliminate over one third of the jobs located in Rosetta, another city in the Delta. Other cities threatened by a rising sea level in the delta include Port Said, Matruh City, and Arish City. 54

55 The Nile Delta is home to much of Egypt s tourism, and for cities like Alexandria or Matruh City, the threat of a rising sea level will reduce both their capability to sustain tourism as well as the desire of tourists to visit them. 49% of Alexandria s tourism industry would be underwater if sea level rose.5-meters. In addition, high levels of carbon dioxide in the atmosphere will result in ocean acidification, destroying coral reefs. The bleaching of the coral reefs is not just the loss of an important ecosystem but also the elimination of a prime tourist attraction. 55

56 Disruption to the Egyptian tourism sector could have broader societal implications, as 20% of Egypt s foreign currency earnings are from tourism and according to Egypt s Minister of Tourism, 12.6% of the workforce depends upon the travel industry. The dangers climate change poses to Egypt s tourism sector and economy as a whole should not be underestimated.

57 While the variability in models prevent a conclusive determination of whether climate change will mean more or less rain at the Nile s source waters, it is clear that the increased evaporation due to rising temperatures will result in greater water stress. Increased scarcity will threaten Egypt s development plans. One third of international monetary support for Egypt s development is for projects involving sectors threatened by climate change. 57

58 As the Nile s waters will probably decreasing, the survival of communities in Ethiopia and other states currently disputing water rights with Egypt will also be placed in great difficulty.

59 As the sea level rises, salt water will infiltrate the North Egyptian lakes where 60% of Egypt s fisheries are located. As the lake water becomes saltier, the aquatic plants that protect the marine life by filtering the contaminated wastewater from Egypt s industry will die off. The shallow nature of Egypt s lakes will provide little protection from temperature increases that could disrupt the marine ecosystems. As Egypt s domestic fisheries face increased risks, Egypt will be forced to import more fish from other nations whose own fisheries will be facing decline.

60 Finally, climate change could exacerbate the food security issues that Egypt already faces. climate change may bring about substantial reductions in the national grain production. Grain is only one of Egypt s food sources endangered by unmitigated climate change. 60

61 Thank You S.R. November 1, 2010