Presentation on theme: "“Do you believe in global warming?” (Jane Doe, OU Sophomore, Elk City, OK) 1. to accept as true or as speaking or convey the truth 2. to have religious."— Presentation transcript:
“Do you believe in global warming?” (Jane Doe, OU Sophomore, Elk City, OK) 1. to accept as true or as speaking or convey the truth 2. to have religious faith, to believe in God 3. to think, to suppose (“I believe it’s raining”) [Oxford American Dictionary, 1979] where believe is defined as
GLOBAL WARMING A Planetary Scale issue – involving transfers of radiation between the Sun, Earth, and Space Let’s assume Earth has no atmosphere … solar radiation is absorbed by Earth’s surface (egg shell thin) and immediately returned to Space as terrestrial radiation … no heat storage occurs The Earth’s surface must have a temperature that supports this radiation balance That temperature is -18˚C (0˚F) … whereas the present global average surface air temperature is +15˚C (59˚F) The difference of +33˚C (+59˚F) is due to the NATURAL GREENHOUSE EFFECT
Circles = yearly values Black curves = decadal averaged Blue areas = uncertainty intervals Red sea level = from satellites GLOBAL WARMING
Blue Area Range of model simulations using natural forcings Red Area Range of model simulations including natural and anthropogenic forcings SIMULATED VERSUS OBSERVED TEMPERATURE (1900-2000) Black Line Decadal averages of observations
} Different Emission Scenarios SIMULATIONS FOR 2000-2100
REGIONAL CLIMATE VARIABILITY With possible exception of high latitudes (say, beyond 60˚), most of what can happen already has occurred. Global warming will be manifest regionally as changes in FREQUENCY DURATION INTENSITY SEASONALITY of regional climate phenomena with which we have familiarity ALREADY
(˚C) TEMPERATURE SIMULATIONS FOR DECADES OF 2020s and 2090s ANNUAL
PRECIPITATION SIMULATIONS FOR 2090s VERSUS 1980s + 1990s December-February June-August
FIRST IPCC (1990) SIMULATIONS JUNE-AUGUST TEMPERATURE JUNE-AUGUST PRECIPITATION FOR CO 2 DOUBLING
DISAPPEARANCE OF LAKE CHAD 1963 1973 1987 2001 From: A. Gore, An Inconvenient Truth, 2006
RAINFALL CHANGE IN SAHELIAN WEST AFRICA 1941-2005
Journal of Climate (August 15, 2006) Article: pp. 3989–4008 Detection and Attribution of Twentieth-Century Northern and Southern African Rainfall Change Martin Hoerling NOAA/Earth System Research Laboratory, Boulder, Colorado James Hurrell National Center for Atmospheric Research, Boulder, Colorado Jon Eischeid NOAA/Earth System Research Laboratory, Boulder, Colorado Adam Phillips National Center for Atmospheric Research, Boulder, Colorado ABSTRACT The spatial patterns, time history, and seasonality of African rainfall trends since 1950 are found to be deducible from the atmosphere’s response to the known variations of global sea surface temperatures (SSTs). The robustness of the oceanic impact is confirmed through the diagnosis of 80 separate 50-yr climate simulations across a suite of atmospheric general circulation models. Drying over the Sahel during boreal summer is shown to be a response to warming of the South Atlantic relative to North Atlantic SST, with the ensuing anomalous interhemispheric SST contrast favoring a more southern position of the Atlantic intertropical convergence zone. Southern African drying during austral summer is shown to be a response to Indian Ocean warming, with enhanced atmospheric convection over those warm waters driving subsidence drying over Africa. The ensemble of greenhouse-gas-forced experiments, conducted as part of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, fails to simulate the pattern or amplitude of the twentieth-century African drying, indicating that the drought conditions were likely of natural origin. For the period 2000–49, the ensemble mean of the forced experiments yields a wet signal over the Sahel and a dry signal over southern Africa. These rainfall changes are physically consistent with a projected warming of the North Atlantic Ocean compared with the South Atlantic Ocean, and a further warming of the Indian Ocean. However, considerable spread exists among the individual members of the multimodel ensemble.
U.S. “ENGAGEMENT” SINCE KYOTO 1. Strong scientific contributions by individuals and groups, including by civil servants in federal agencies and university scientists receiving federal funding. 2. Manifest in recently released Fourth Assessment of IPCC … which was acknowledged by NOAA Administrator (political appointee). BUT 3. U.S. Climate Change Science Program (CCSP) produced little more than a few “Assessment Reports”. 4. On the policy, technology, alternative energy, and regulatory sides ….? 5. PEW Foundation survey identified U.S. lack of response to global warming as second reason (after Iraq War) for declining U.S. respect in World.
“Do you believe in ….?” Conservative Christianity Evolution Global Warming Stem Cell Research
“Do you believe that …?” U.S. Scientists have played their part thus far? U.S. politicians and diplomats now have important leadership roles to play … to the point of statesmanship?