docAn Update on Global Warming
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An Update on Global Warming
An Update on Global Warming Ray Bradley Climate System Research Center University of Massachusetts Amherst Chacaltaya Glacier, Bolivia, ~5240m “The threat of catastrophic global warming is the greatest hoax ever perpetrated on the American people … maninduced global warming is an article of religious faith…” Senator James Inhofe (R-Oilahoma) Max Trends (1950-2003) Source: Trenberth, NCAR 2005 Source: Raynaud et al., 2003 “Northern Hemisphere temperatures during the past millennium: inferences, uncertainties and limitations” M. Mann, R. Bradley & M. Hughes, 1999 WARMEST 50 YEARS BEFORE 1900: 1146-1195 COLDEST 50 YEARS BEFORE 1900: 1453-1502 “Mann[et al] effectively erased the well-known phenomena of the Medieval Warming Period-when, by the way, it was warmer than it is today--and the Little Ice Age…” J. Inhofe 2005 Blue=CO2 (carbon dioxide) Red=CH4 (methane) Homo erectus Homo sapiens Dec 4th 2005: 380ppm 280ppm 180ppm Hundreds of thousands of years before today Source: Houghton et al., 2001 ~760ppm Blue=CO2 (carbon dioxide) Red=CH4 (methane) Homo erectus Homo sapiens Dec 4th 2005: 380ppm 280ppm 180ppm Hundreds of thousands of years before today Source: Houghton et al., 2001 CO2 change over the last 650,000 years Source: Siegenthaler et al., 2005 Internal combustion engine New World 290 colonization 280 The Crusades 280 First Cities 270 1 hour = 6000 years; 1 minute = 100 years First Writing 275 Time… 2003 2005 2003 NCEP Reanal. Mean Annual Temp - Cordillera Transect (1973-2002) 200 300 400 mb 500 Freezing level 600 700 800 900 1000 -50 -40 -30 -20 -10 0 10 20 30 40 0 10 20 latitude -50 -40 -30 -20 -10 °C 50 60 70 1932: Glacier National Park Boulder ice cave 1988: Glacier National Park Boulder ice cave http://www.nrmsc.usgs.gov/research/FTP-Instructions_repeatphotos.pdf 1910 Recession of the Grinnell Glacier 1931 “Glacier National Park” 1997 Source: D. Fagre, USGS, 2004 1929 2000 1930 Photo: Mittelholzer, Kilimanjaro Flug 5 Photo credit: Nicolas Cullen, Univ. Innsbruck Glacier on Volcán Lanin, Argentina, 1896 and 2001 Chacaltaya Glacier Bolivia: Water supply for La Paz 5M m3 m in 1940 <0.3M m3 m today Widespread (global) glacier recession 169 glaciers: Source: Oerlemans, 2005 Source: Trenberth, NCAR 2005 Permafrost occurrence at the Matterhorn Permafrost Permafrost probable Zermatt Source: Gruber & Biegger 2003 Climate change in mountains affects water supply Shifting the timing of fresh water runoff impacts Delta water quality Current average April snow water equivalent in Sierra Nevada (CA) current average Percentsnow reduction April waterinequivalent SWE with 1.6 °CNevada rise by (CA) in Sierra 2060 (Knowles and Cayan 2004) Even in non-glaciated mountains such as in Central California, warming will lead to more rain and less snow, and earlier melting, less in summer = salt-water intrusion more in winter = flooding? 30°N-30°S: 3.8% increase in total water vapor since 1970 Source: Trenberth, NCAR 2005 Source: Enfield et al., 2001 Yearly changes in ocean heat content (1955–59 to 1994–98) (units = 1022 J) Source: Levitus et al., 2005 Trends in ocean heat content (1955-2003). Pink = increasing Contour interval is 2 x 1018 J year-1 Source: Levitus et al., 2005 Greenhouse gas forcing Annual mean temperature change, 2071 to 2100, relative to 1990: global average in 2085 = +3.1oC Greenhouse gas forcing Annual mean precipitation change: 2071 to 2100, relative to 1990 Source: Overpeck et al.,2003 The Earth at night Today there are ~6.3B people, & our impact on the planet is ubiquitous… World population is currently increasing by 240,000 per day…. By 2060, UN projections indicate world population will be ~9B… Number of years to add each billion First Billion Second Third Fourth Fifth Sixth Seventh Eighth Ninth Year All of Human History 130 30 14 13 12 14 15 26 1800 1930 1960 1974 1987 1999 2013 2028 2054 Sources: Population Reference Bureau; UN World Population Prospects (1998) Conservation [less waste], reduced consumption + alternative energy sources Source: R. Hoblitt, USGS 1834 WARMEST EUROPE COLDEST 1838 EUROPE Source: Mann et al., 2000 For accurate information about climate change & global warming, see: http://www.realclimate.org www.paleoclimate.org
