Global Warming Eugene S Takle Ph D CCM

Global Warming Eugene S. Takle, Ph. D, CCM Professor of Atmospheric Science Professor of Agricultural Meteorology Iowa State University Ames, Iowa 50011 gstakle@iastate. edu Iowa Soil and Water Conservation Society, 22 September 2006 PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Carbon Dioxide and Temperature

Carbon Dioxide and Temperature 2006

Carbon Dioxide and Temperature 2040 2006

Carbon Dioxide and Temperature Stabilization at 550 ppm

Carbon Dioxide and Temperature “Business as Usual” (fossil intensive) 2100

“Nobody believes that the US economy can still be petroleum based in 2050, yet there is no national plan” Mark Kushner, Dean Iowa State University College of Engineering President’s Council Meeting 13 January 2006 PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Contributions to “global dimming” PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Source: IPCC, 2001: Climate Change 2001: The Scientific Basis

Associated Climate Changes Global sea-level has increased 1 -2 mm/yr Duration of ice cover of rivers and lakes decreased by 2 weeks in N. Hemisphere Arctic ice has thinned substantially, decreased in extent by 10 -15% Reduced permafrost in polar, sub-polar, mountainous regions Growing season lengthened by 1 -4 days in N. Hemisphere Retreat of continental glaciers on all continents Poleward shift of animal and plant ranges Snow cover decreased by 10% Earlier flowering dates Coral reef bleaching Source: Intergovernmental Panel on Climate Change, 2001 Report PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Since 1979, the size of the summer polar ice cap has shrunk more than 20 percent. (Illustration from NASA) (http: //www. nrdc. org/global. Warming/qthinice. asp)

Tropical Atlantic Ocean Hurricane Power Dissipation Index (PDI) Sea-surface temperature V V V Emanual, Kerry, 2005: Increasing destructiveness of tropical cyclones over the past 30 years. Nature, 436, 686 -688.

PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Tropical Weather Underground: http: //www. wunderground. com/tropical/

http: //en. wikipedia. org/wiki/Image: Katrina_vs_sea_surface_height. JPG

Source: Jerry Meehl, National Center for Atmospheric Research

Source: National Center for Atmospheric Research

The planet is committed to a warming over the next 50 years regardless of political decisions Source: National Center for Atmospheric Research

The planet is committed to a warming over the next 50 years regardless of political decisions Mitigation Possible Adaptation Necessary Source: National Center for Atmospheric Research

Source: Intergovernmental Panel on Climate Change, 2001 Report

40% Probability 5% Probability Source: Intergovernmental Panel on Climate Change, 2001 Report

Source: Corell, R. W. , 2004: Impacts of a warming Arctic Climate Impact Assessment (www. acia. uaf. edu) Cambridge University Press (www. cambridge. org).

Jakobshavn Ice Stream in Greenland Discharge from major Greenland ice streams is accelerating markedly. Source: Prof. Konrad Steffen, Univ. of Colorado PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Arctic Climate Impact Assessment (ACIA) 140 -page synthesis report released in November 2004. Main science report imminent (chapters available electronically at www. acia. uaf. edu). Concerns over wide-ranging changes in the Arctic. – – – Rising temperatures Rising river flows Declining snow cover Increasing precipitation Thawing permafrost Diminishing late and river ice Melting glaciers Melting Greenland Ice Sheet Retreating summer sea ice Rising sea level Ocean salinity changes Species at risk include polar bears, seals, walruses, Arctic fox, snowy owl, and many species of mosses and lichens Sources: Claire Parkinson and Robert Taylor

Increasing Melt Area on Greenland • 2002 all-time record melt area • Melting up to elevation of 2000 m • 16% increase from 1979 to 2002 70 meters thinning in 5 years Satellite-era record melt of 2002 was exceeded in 2005. Source: Waleed Abdalati, Goddard Space Flight Center

Scientific Consensus of Five Years Ago Likely Underestimated Rate of Climate Change* Global dimming has decreased Permafrost melting is widespread Biomass feedbacks are kicking in Arctic sea ice is retreating rapidly Poleward movement of mid-latitude westerlies; strengthening of ocean gyres Rapid Greenland Antarctic ice-shelf disintegration Increased intensity of tropical cyclones Accelerated changes in North Atlantic ocean thermohaline circulation REGIONAL climate CLIMATE SIMULATIONS * Pittock, A. PROJECT B. , 2006: TO Are. INTERCOMPARE scientist underestimating change? EOS, 87, 340.

For the Midwest Warming will be greater for winter than summer Warming will be greater at night than during the day A 3 o. F rise in summer daytime temperature triples the probability of a heat wave Growing season will be longer (8 -9 days longer now than in 1950) More precipitation Likely more soil moisture in summer More rain will come in intense rainfall events Higher stream flow, more flooding

Climate Surprises Breakdown of the ocean thermohaline circulation (Greenland melt water) Break-off of the West Antarctic Ice Sheet PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Kennedy Space Center Areas subjected to Inundation with a 1 m (~3 ft) rise in sea level Miami PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

What Constitutes “Dangerous Anthropogenic Interference with the Climate System”? James Hansen, Director of the NASA Goddard Institute for Space Studies: * Radiative forcing limit: 1 Watt/ m 2 * 1 o. C additional rise in global mean temperature PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Agung, 1963 El Chichon (1982) Mt. Pinatubo (1991) Hansen, Scientific American, March 2004

Agung, 1963 El Chichon (1982) Mt. Pinatubo (1991) Imbalance = 1 Watt/m 2 in 2018 Hansen, Scientific American, March 2004

Hansen, Scientific American, March 2004 PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Kennedy Space Center Impact of a 1 -m rise in sea level on low-lying areas Projected sea-level rise In 21 st century: 0. 5 to 1. 0 m Areas subjected to Inundation with a 1 m (~3 ft) rise in sea level Miami Source: Corell, R. W. , 2004: Impacts of a warming Arctic Climate Impact Assessment (www. acia. uaf. edu) Cambridge University Press (www. cambridge. org).

“Another ice age cannot occur unless humans become extinct. Even then, it would require thousands of years. Humans now control global climate, for better or for worse. ” James E. Hansen, Director NASA Goddard Institute for Space Studies New York City PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Climate Model Resolution global regional (land) regional (water) Only every second RCM grid point is shown in each direction

Summary Climate change is real and we need to be doing something about it to prevent “dangerous anthropogenic interference with the climate system” Mitigation will have no effect for 50 years, so we need to develop adaptation strategies for the short term The longer we wait, the fewer our options Regional patterns of warming will be complicated Climate surprises can’t be discounted We need dialog between scientists and the private sector to develop both adaptation and mitigation strategies PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

For More Information For peer-reviewed evidence supporting everything you have seen in this presentation, see my online Global Change course: http: //www. meteor. iastate. edu/gccourse Contact me directly: gstakle@iastate. edu PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS