Climate Change Issues Natural Sciences Social Sciences by
Climate Change Issues: Natural Sciences - Social Sciences by Dr. Ishfaq Ahmad Sp. Assistant to the Prime Minister of Pakistan & President, Pakistan Academy of Sciences January 26, 2008
Climate Change u u Climate describes an overall average of weather conditions occurring over time periods of the order of decades ; Climate change is occurring at an accelerated pace due to anthropogenic activities : ―Greenhouse effect is a process in which the incoming solar radiations are trapped by GHGs (CO 2, methane, ozone, water vapors etc) in the earth’s atmosphere ; ―Atmospheric CO 2 concentration has increased from 280 (pre industrial value) to 380 ppm and continues to increase @ 2 -3 ppm per year as shown in next slides. 2
Past 1000 Year Changes in Temperature and CO 2 Concentrations 0. 6 0. 5 0. 4 0. 2 0. 1 0 -0. 1 -0. 2 3 Temperature Change (o. C) 0. 3
Accelerated Global Warming Warmest 12 years: 1998, 2005, 2003, 2002, 2004, 2006, 2001, 1997, 1999, 2000, 1995, 1990 Rate of Change (o. C per decade) 1850 – 2005 ─────── 0. 045 1905 – 2005 ─────── 0. 074 1955 – 2005 ─────── 0. 128 1980 – 2005 ─────── 0. 177 4
Climate Change – Global Warming u A direct manifestation of Climate change is the global warming: ―Global temperatures increased at an unprecedented pace. Eleven of the past 12 years have been the warmest since 1850, with 2005 as the warmest year (NASA) and 2007 being the second warmest in the recorded history; ―Global warming is causing melting of glaciers leading to sea level rise and inundation of low lying areas. Many small islands would submerge under water and the World map would change. Millions of people will become climate refugees. 5
Risks associated with the rapid Climate Change u u u Increased frequency & intensity of extreme climate events: heavy rains, severe sea storms, hurricanes/ typhoons/cyclones will cause large scale disasters ; Increased occurrence of floods and droughts will cause loss of valuable agricultural land, widespread famine, extinction of species ; Loss of natural water reservoirs in the form of glaciers resulting in large variability in river flows; Glacier lakes outburst floods (GLOFs) ; Global warming will cause further warming and the climate system may reach a tipping point with an irreversible damage. 6
Climate Change & Melting of Glaciers • Due to global warming mountain glaciers worldwide have been receding in general, however glaciers in the Himalayas are receding at a faster pace; Fears expressed that many of these may disappear by 2050. Figure below shows the terminus positions of the Glacier EB 060 (in central Himalayas), as observed in 1997 and 2004: Source: ICIMOD 1997 2004 7
Melting of Karakoram Glaciers • Situation of Karakoram glaciers not quite clear. Some evidence of glacier expansion in the region. • Karakoram environment different from the rest of Himalayas: § Most (about 2/3) snow nourishing of Karakoram due to westerly circulation in winter versus dominant summer accumulation in Greater Himalayas. § Shadowing caused by closely lying peaks in the Karakoram. § Thick debris ( > 5 cm ) in the lower ablation zones of Karakoram glaciers reduce melting versus increased melting in Greater Himalayas due to thin debris or a few mm of dust cover. § More frequent cloudiness in the Karakoram reducing incoming solar radiation. 8
Research Needs in the HKKH Region Recent IPCC Assessment Report (AR 4) indicated the lack of data and knowledge in the Himalayan region 9
Observed climate change in different regions of the world (1970 -2004), highlighting the lack of data in the Hindu Kush-Himalayan region Source: IPCC 2007 10
CC Impacts & Vulnerabilities for Pakistan u u u u River flows would be increased initially due to rapid glacier melting followed by substantial reduction ; Increased risk of severe floods and droughts ; Changed precipitation patterns would require a complete transformation in agricultural practices; Increased occurrences of vector born diseases ; Sea-level rise would cause intrusion of saline water in Indus deltas ; Ecology of the Indus delta regions will change ; Increased risk of damage due to severe sea storms, cyclones etc. at coastal areas. 11
Climate Change Research in Pakistan u Proposal of a dedicated Research Centre for Systematic Studies on Climate Change was initiated by us ; u Global Change Impact Studies Centre (GCISC) established in 2003. 12
GCISC Approach for CC Research Area of GCISC Activities at Present Internal driving forces Information at 300 km x 300 km level Regional Climate Models (RCMs) Global Climate Scenarios Land use & Topographic data etc. Super Computer Anthropogenic Influences Adaptation Measures Watershed Models Effect on River inflows Mesoscale Climate Models (MMs) Effects on Crop Yields Information at 30 km x 30 km level Crop-growth Simulation Models Agriculture Information at Sub-km level Adaptation Measures Future Activities Health Energy Biodiversity 13 Impact Studies External driving forces Regional Climate Scenarios Global Circulation Models (GCMs)
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UPPER INDUS BASIN 15
Impact of Climate Change and Glacier retreat on UIB Flows Assumed Climate Change Scenario (CCS): Temp: +3°C, Glacier Area: - 50% Main Results: 1. Annual flows reduced by 15% 2. Intra-Annual flow pattern considerably changed 16
Response to Climate Change Avoiding the Unmanageable Managing the Unavoidable Mitigation – Adaptation Renewable (solar, wind, nuclear) -- Conservation in use of water/energy Efficient hybrid & Bio-fuels -- Heat /drought resistant crops -- Change in cropping pattern Recycling & Compositing . 17
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