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CLIMATE CHANGE - HERE. EVSC 100. Reminder. EVSC 100: Exam next time we meet EVSC 305: Outline due November 3; Exam November 13; Prospectus November 18. Reminder. high degree of probability (98%) that human activities have caused a substantial net warming influence on climate since 1750
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climate change impact CLIMATE CHANGE - HERE EVSC 100
Reminder • EVSC 100: Exam next time we meet • EVSC 305: Outline due November 3; Exam November 13; Prospectus November 18 climate change impact
Reminder.. • high degree of probability (98%) that human activities have caused a substantial net warming influence on climate since 1750 • global surface air temperature increased from 1850 to 2005 by 0.76ºC. • linear warming trend over the last 50 years is recorded by 0.13ºC per decade • Plus, there has been an increase in the number of heat waves, a decrease in the frequency and duration of frosts, and an increase in extreme events frequency and intensity in many parts of the world. • recent studies found that the Arab region experienced an uneven increase in surface air temperature ranging from 0.2 to 2.0ºC that occurred from 1970 to 2004 climate change impact, AFED
Tomorrow… • For the next 20 years: • A warming of about 0.2 C • Even IF the [ ] of all greenhouse gases and aerosols had been kept constant at 2000 year levels, another warming of 0.1 C / decade would be expected climate change impact
GHGs emissions (2000) • 33 thousand Tg (teragram) • Arab: 4.2% of total world emissions • KSA • Egypt • Algeria North America 37.1 South America 22.9 Africa (non-Arab) 22.8 Central America and Caribbean 5.4 Arab countries 4.2 Asia (non-Arab) 3.6 Europe 2.2 Oceania 1.7 climate change impact
Impact high… • Semi-arid and arid regions are highly vulnerable to climate change • If temperature gets higher • If precipitation gets lower • pressure on natural and physical systems would be intensified climate change impact
The Arab region will… • Face an increase of 2 to 5.5 C in surface temperature by 2100 • Face a decrease in precipitation from 0 to 20% • shorter winters • dryer and hotter summers • higher rate of heat waves • higher level of weather variability • more frequent occurrence of extreme weather events climate change impact
Let’s talk details: Sea Level Rise climate change impact
Impact of Sea-Level Rise • Important consequence of climate change and a serious global threat • Rate of sea level rise was observed to be 1.8 mm per year from 1961-2003, and higher from 1993-2003 (3.1 mm) • Total 20th century rise: 0.17 m • Continued growth of GHG SLR of 1 to 3 m + very quick breakup of Greenland and West Antarctic ice sheets = 5 m SLR • Nature of impacts of SLR changes from place-to-place and from country-to-country. Why? • Highest exposure: river deltas. Low-lying coastal urban areas. Small islands climate change impact
UN-Habitat's State of the World's Cities 2008/09 During the 1900s, sea levels rose by an estimated 17cm; global mean projections for sea level rise between 1990 and 2080 range from 22cm to 34cm, according to the UN-Habitat researchers. The report points out that by 2070, urban populations in river delta cities, such as Dhaka, Kolkata (India), Yangon (Myanmar), and Hai Phong (on the coast near Hanoi in Vietnam), which already experience a high risk of flooding, will join the group of populations most exposed to this danger. Port cities in Bangladesh, China, Thailand, Vietnam, and India will have joined the ranks of cities whose assets are most at risk. African coastal cities that could be severely be affected by rising sea levels include Abidjan (Cote d'Ivoire), Accra (Ghana), Alexandria (Egypt), Algiers (Algeria), Cape Town (South Africa), Casablanca (Morocco), Dakar (Senegal), Dar es Salaam (Tanzania), Djibouti (Djibouti), Durban (South Africa), Freetown (Sierra Leone), Lagos (Nigeria), Libreville (Gabon), Lome (Togo), Luanda (Angola), Maputo (Mozambique), Mombasa (Kenya), Port Louis (Mauritius), and Tunis (Tunisia). climate change impact
Impact of SLR - Egypt • A 1 m SLR • 6 million people • 12 to 15% of agricultural land in the Nile Delta • A 0.5 m SLR • A loss of more than 90% of the governorates under risk • Loss of 65% in industrial sector • Loss of 55% in tourism sector climate change impact
Impact of SLR • Qatar • 13% land loss with 5 m rise • Egypt • 10% of pop impacted with 1 m rise • 20% - 5 m rise • UAE and Tunisia • 1 m – 5% of pop • Urban areas also… • 5% in Egypt, Libya, UAE, and Tunisia with 1 m SLR • 6 to 7 % with 2 m SLR • 10% with 5 m SLR • High uncertainty climate change impact
Impact on freshwater sources climate change impact
Water and Climate Change (1) The distribution of precipitation in space and time is very uneven, leading to tremendous temporal variability in water resources If all the freshwater on the planet were divided equally among the global population, there would be 5 000 to 6 000 m3 of water available for everyone, every year. (2) the rate of evaporation varies a great deal, depending on temperature and relative humidity, which impact the amount of water available to replenish groundwater supplies. The combination of shorter duration but more intense rainfall (meaning more runoff and less infiltration) combined with increased evapotranspiration (the sum of evaporation and plant transpiration from the earth's land surface to atmosphere.) and increased irrigation is expected to lead to groundwater depletion. climate change impact
Hydrological cycle climate change impact
Key changes to the hydrological cycle … associated with an increased concentration of greenhouse gases in the atmosphere and the resulting changes in climate include: * Changes in the seasonal distribution and amount of precipitation * An increase in precipitation intensity under most situations * Changes in the balance between snow and rain * Increased evapotranspiration and a reduction in soil moisture * Changes in vegetation cover resulting from changes in temperature and precipitation * Consequent changes in management of land resources * Accelerated melting glacial ice * Increases in fire risk in many areas * Increased coastal inundation and wetland loss from sea level rise * Effects of CO2 on plant physiology, leading to reduced transpiration and increased water use efficiency climate change impact
Status of freshwater here • Reminder: most of the Arab countries are located in arid and semi-arid regions; low and limited water resources + high evaporation • Total water resources = total renewable ground water + internal surface water resources + external surface water resources climate change impact
Water resources here • Iraq, Sudan and Egypt • Highest annual water resources ( > 50 billion m3/yr) • More than 50% of their surface resources are external • Algeria, Lebanon, Mauritania, Morocco, Somalia, Syria, Tunisia, and Yemen • Between 5 to 30 billion m3/yr • Rest • < 5 billion m3/year climate change impact
rainfall • Varied • Lebanon and Syria: average 600 and 300 mm/yr • Move N and E to Morocco and Tunisia – decreases to 300 mm/yr • North Africa and Arab Peninsula – 130 mm/yr • Rest – average – 290 mm/yr • Kuwait: poorest water resources • Egypt – second lowest climate change impact
? • How will sea-level rise impact freshwater? • How will CC conditions impact watersheds? • Due to CC and population, FAO projects that Algeria, Egypt, Morocco, Syria and Tunisia – severe water shortages by 2050 Water demand increasing Water supply decreasing Plus problems of accessibility of water climate change impact
First order impacts… • Mediterranean hydrological systems • Wetter winters • Dryer and hotter summers • Increase in evaporation from water bodies… • Increase Evapotranspiration from crops • Egypt • Increase the potential irrigation demand by 6 to 16% by 2100 climate change impact
Drought climate change impact
Impact of increasing drought • One of the serious water related disasters threatening the Arab region for both current and future time scales • What is drought? • “a temporary reduction in water or moisture availability significantly below the normal or expected amount for specified period” (climatic viewpoint) • “a period of abnormally dry weather sufficiently prolonged for the lack of precipitation to cause a serious hydrological imbalance, carrying connotation for moisture deficiency with respect to [hu]man’s usage of water” (hydrological viewpoint) climate change impact
Droughts… • Impact rain-fed agricultural production • Impact water supply for domestic, industrial, and agricultural purposes climate change impact
Drought frequency • Increased during the last 20 to 40 years in Morocco, Tunisia, Algeria and Syria • Of the 22 drought years in the 20th century, 10 occurred in the last 20 years, and three were successive (1999, 2000, 2001) in Morocco • Recent droughts in Jordan and Syria worst ever recorded • Varying conditions of water shortage in Lebanon in the last 10 years climate change impact
But not just droughts climate change impact
Warmer climate • Increase risk of both droughts AND floods • Drought affected areas will (probably) increase • Extreme precipitation events likely to increase in frequency and intensity more flood risk climate change impact
Yemen: drought • SANAA, 2 September 2008 (IRIN) - Hundreds of families (totalling about 2,000 people) in the southern governorate of Abyan have begun to leave their homes due to severe drought in their mountain villages • Sirar villages are arid, barren and mountainous. Any rain that does fall quickly runs off down the steep valley sides, as there are no dams in the area to harvest rainwater. • people had installed small concrete tanks on their houses to harvest rainwater, but these had remained dry because of the lack of rain • The drought has caused damage to the livestock, beehives and farms on which local people are heavily dependent for their livelihoods. climate change impact
Yemen Yemen Times: “The climate changes during the last few years and especially this year is a real concern for Yemen, particularly if the frequency of precipitation events diminish, putting rainfall and agriculture in peril and lead to a catastrophic drought,” said Anwar Abdulaziz, head of the Climate Change Unit in the General Authority of Environment Preservation. "Every year the rain season starts at the beginning of March, and now Yemen is in the end of April and there is still no rain. This means that Yemen is truly affected by the climate changes," said Abdulaziz. Though his agency has yet to complete studies on exact drought percentage increase, he is sure that this year and the next year will be difficult for Yemen because of the lack of rain. According to the National Council for the Climate, there has been an increase in average temperatures in Sana’a over the last 20 years, though they do not have the exact percentage due to a lack of research. The expectation is that cities like Sana’a and Ibb will face cloudless skies and will cause more temperature rises, adds Abdulaziz. climate change impact
Yemen: recent floods (October 2008) Dubbed the 'Manhatten of the desert', Shibam's 2,000-year-old mud-brick buildings are in danger of collapsing after recent floods climate change impact
Human health Sea-level rise will affect groundwater aquifers in coastal areas and flood low-lying areas, reducing freshwater availability. It is estimated that by 2030 the risk of diarrhoea will be up to 10 percent higher in some countries due to climate change. Greater migration as a result of water stress or increased food insecurity means that diseases will be transported to other regions, where they may or may not be able to survive, potentially exposing host communities to new diseases. "Policies at various levels and their implementation, however, do not reflect this principle," the authors noted. "Improved access to clean water can reduce diarrhoea and waterborne diseases by at least 25 percent; improved sanitation is accompanied by more than a 30 percent reduction in child mortality. This urgent global challenge is pragmatically achievable, politically feasible and ethically important." (IPCC) climate change impact