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The Global Warming-Extreme Weather link: Media Hype or Climate Realty? Madhav Khandekar Expert Reviewer IPCC 2007 Climate Change July 7-9, 2014 Climate change Conference Las Vegas, USA Are EW events on the rise? A short answer: NO! A Long answer: NO! NO! NO! EW events have always occurred in the earth’s climate! Present concern re: EW/Global Warming (GW) link is more media hype than reality! July 7-9, 2014 Climate change Conference Las Vegas, USA IPCC vs NIPCC IPCC: Intergovernmental Panel on Climate Change; A UN Body of scientists (mostly working with various national governments) established in 1988: IPCC has issued climate change documents since 1990. NIPCC: Nongovernmental International Panel on climate change (several dozen scientists & specialists in various fields) established in 2007: First comprehensive report in 2009 July 7-9, 2014 Climate change Conference Las Vegas, USA Mechanics of extreme weather (EW) IPCC View Warmer climate holds more moisture: more rains & floods in some areas; droughts/heat waves in other areas. NIPPC View Extreme weather is an integral part of earth’s climate: have occurred throughout recorded history of climate. More intense Trop Cyclones ENSO phases can and do cause EW events world-wide Increase in extreme rainfall events Decrease in cool days/night and frost in Mid-latitudes Intense interaction between high-lat. cold air with low-lat. warm air produces EW events regionally/locally EW are on the rise now due to warming of climate. Present ‘increase’ in EW is perception than reality! July 7-9, 2014 Climate change Conference Las Vegas, USA IPCC 2007 Table of Extreme Weather Events July 7-9, 2014 Climate change Conference Las Vegas, USA Media Hype about global warming & Impacts July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA Global Mean Temperature Trend July 7-9, 2014 Climate change Conference Las Vegas, USA IPCC 2007 July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA U.K Met office data July 7-9, 2014 Climate change Conference Las Vegas, USA Heat Waves: Highest worldwide temperatures July 7-9, 2014 Climate change Conference Las Vegas, USA Heat Waves: North America & Elsewhere North America witnessed recurring heat waves in 1920s and 1930s! Highest max temperatures in the 1920s 1930s! 2012 US summer heat-wave was ‘mild” compared to those of 1930s! Summer 2003 Western Europe heat-wave was extreme; Dry soil moisture conditions were responsible ( NIPPC post 7 March 2012) Moscow heat-wave summer 2010 was due to atmospheric blocking (NIPPC post 13 July 2011) Pre-Monsoon (April-May) heat waves over India are common & exhibit inter-annual variability Heat waves over Australia linked to ENSO phases 2013 July heat wave over China was due to drying of soil moisture July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA Deadliest heat wave in Canada; 1100 people died July 1936 July 7-9, 2014 Climate change Conference Las Vegas, USA Highest Recorded Temperatures World’s highest: 57.8C (136F) Libya 13 Sept 1922 Canada’s highest:45C Saskatchewan Canadian Prairies, July 1937: Toronto highest 41C July 1936 US highest: 56.7C (134F) California 10 July 1913 Highest on Indian subcontinent: ~128F NW India, 1930s Highest in China: 43.4C Central China 1 September 2006 July 7-9, 2014 Climate change Conference Las Vegas, USA Thunderstorms & Tornadoes Highest thunderstorm/tornado activity in US during 1920s thru 1940s Deadliest tornado outbreak: 18 March 1925: 747 dead in 3 mid-western States April 5 1936: 216 deaths in Mississippi Largest 2-day outbreak; 3-4 April 1974, over 140 tornadoes The Oklahoma tornado (May 22 2013) was due to a cold-air outbreak, resulting in a sharp temperature change, producing intense tornado with several deaths July 7-9, 2014 Climate change Conference Las Vegas, USA Improved monitoring technology may have led to higher tornado count in recent years July 7-9, 2014 Climate change Conference Las Vegas, USA Hurricanes, Typhoons & Tropical Cyclones Hurricanes in North Atlantic & Typhoons in Western Pacific show inter-decadal variability, with NO long-term trend! Bay of Bengal tropical cyclones show inter-annual variability; NO trend! Elsewhere (Australia, South Indian Ocean) NO long-term trend! July 7-9, 2014 Climate change Conference Las Vegas, USA Atlantic Multidecadal Oscillation July 7-9, 2014 Rapid warm-up in the Atlantic in 1995 brought an immediate doubling in number hurricanes and major hurricanes (back to where we were in 1930s to 1960s) It is the basis of forecasts by Dr. Bill Gray (CSU) and others of enhanced activity for another decade or so Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA Bay of Bengal # of Tropical Cyclones June-September 20 Occurance 15 10 5 0 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 -5 Year July 7-9, 2014 Climate change Conference Las Vegas, USA Extreme Precipitation Precipitation extremes have occurred irregularly in various regions without being forced by AGW! Extreme precipitation often linked to tropical cyclones/hurricanes: Also in monsoonal climate Highest 24-hr: 18Jan1966; 182cm (south Indian Ocean: TC-Hyacinthe) Highest one month: July 1861 930cm (Cherrapunji India) Highest one year: 1860-61 2647cm (Cherrapunji India) Recent studies on “human link to extreme rainfall” are without any merit! (rainfall amounts only ~50-150mm locally: UK, Europe, North America) July 7-9, 2014 Climate change Conference Las Vegas, USA Droughts-floods & ENSO Warm events (El Nino) in the equatorial Pacific brings summer rains over US/Canadian Prairies Cold events ( La Nina) linked with drier summer on the Prairies. El Nino/La Nina linked to droughts/floods in Indian summer monsoon ENSO and PDO-Pacific Decadal Oscillation produce dry/wet conditions over eastern Australia, Indonesia, southeast China and eastern Africa. ENSO is the single largest cause of global extreme precipitation events July 7-9, 2014 Climate change Conference Las Vegas, USA PDO COLD MODE PDO WARM MODE Mostly El Ninos Wolter Mostly La Ninas July 7-9, 2014 Climate change Conference Las Vegas, USA The 1997/98 El Nino structure at about Sep 1997 July 7-9, 2014 Climate change Conference Las Vegas, USA Prairie drought-wet cycles 1978-80 Wet Cycle 1987-89 Drought Cycle 1992-94 Wet 2001-03 Drought 2005-2010 Wet Wet Cycle on the Canadian Prairies Continues at present: July 7-9, 2014 Climate change Conference Las Vegas, USA 33 Meteorological Drought Meteorological drought conditions for September 2001- August 2002 (a). Areas in red are record dry conditions. Contrast with conditions observed September 2005 – August 2006 (b). July 7-9, 2014 Climate change Conference Las Vegas, USA Major floods/droughts in Indian summer monsoon (1813-2010) FLOODS 1818 (1036 mm) 1861 (1051 mm) 1874 (1033 mm) 1878 (1039 mm) 1892 (1050 mm) 1894 (1032 mm) 1916 (1034 mm) 1917 (1079 mm) 1933 (1042 mm) 1942 (1037 mm) 1956 (1007 mm) 1961 (1088 mm) 1971 (1002 mm) 1988 (1047 mm) Mean 1041mm July 7-9, 2014 Heaviest flood DROUGHTS 1823 1824 1832 1840 1844 1848 1851 1860 1864 1868 1877 1899 1918 1920 1941 1965 1972 1979 1982 1986 1987 2002 2009 (795 (770 (775 (774 (788 (688 (744 (733 (748 (777 (609 (695 (661 (786 (785 (741 (708 (723 (788 (780 (739 (715 (698 mm) mm) mm) mm) mm) mm) mm) cm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) mm) Mean 739 mm Climate change Conference Las Vegas, USA Worst drought Severe Drought July 7-9, 2014 Climate change Conference Las Vegas, USA Floods in Pakistan and NW India July 7-9, 2014 Climate change Conference Las Vegas, USA July 7-9, 2014 Climate change Conference Las Vegas, USA Recent Cold Weather Extremes Winter 2013/14 was one of the coldest, longest and snowiest over Canada and most of Conterminous US! Winter 2012/13: Extremely cold over most of Europe: March 2013 broke several cold weather records! January 2013 was very cold over most of North and central India! Winter 2011/12: Coldest February 2012 in eastern Europe! Low temperature -40C and below in some localized regions! Winter 2009/10: Very cold over eastern & central Europe: several deaths in eastern Europe & Germany: Heavy snow caused several transportation disruptions in Central Europe: Siberia suffered its coldest winter ever! Several hundred deaths in Northern India due to long exposure to cold weather! Winter 2007/08: snowiest winter in Northern Hemisphere since 1966: Sea Ice between Greenland & eastern Canada was highest in 15 years. Heavy snow in China! Buenos Aires (SA) recorded several cm of snow (July 2007) after 85 years! Winter 2005/06: Very Cold most of Europe! Winter 2002/03: Severe cold in eastern Europe, 200 deaths in Poland: Several hundred deaths in Bangladesh & Vietnam, January 2003! July 7-9, 2014 Climate change Conference Las Vegas, USA Notable EW events of 1945-1977 (when mean temperature declined) 1961 summer monsoon over India: Heaviest floods everywhere! Also East Pakistan (Now Bangladesh) witnessed two powerful cyclones in May! Over 20,000 deaths India & Pakistan! Winter 1962-63: One of the Coldest over most of Europe! Rivers in central Europe frozen for weeks! August 1969: Hurricane Camille (category 4-5) struck US Gulf Coast killing over 250 people! November 1970: tropical cyclone hit Bangladesh killing over 250,000 people! Largest human fatalities in ONE SINGLE WEATHER DISASTER April 2-3 1974: largest (147) outbreak of tornadoes in US Midwest ever! Over 250 deaths; property damage over US$ 1 billion December 1976-January 1977: Very cold over most of North America! Southeast US witnessed long cold winter July 7-9, 2014 Climate change Conference Las Vegas, USA Summary & Conclusions EW events are integral part of earth’s climate. Recent perceived increase in EW events is due to media hype! Heat waves, droughts, floods etc have occurred in the past, without being triggered by Global Warming! NO increasing trend in heat waves, droughts etc at present! Hurricanes, tropical cyclones are NOT increasing in strength NOR in frequency at present. Intense tornado frequency in US has NOT increased, more tornado being recorded today due to improved detection and monitoring. Indian/Asian Monsoon droughts and floods have occurred irregularly! NO increase/decrease in Monsoon droughts/ floods in recent years. World-wide droughts show NO change in last 60 years! Cold Weather Extremes have increased in recent years worldwide, contrary to IPCC projection. EW (cold or warm) will continue to occur in future! Need to develop better resilience to cope with future EW events! July 7-9, 2014 Climate change Conference Las Vegas, USA