107-1 Hearing: Climate Change: The State of The Science, Serial No. 107-13, March 14, 2001

Aeronomy aerosols ALBRITTON anthropogenic areas better carbon cycle carbon dioxide century Chairman BOEHLERT challenge climate change climate models climate system climate variability cloud feedback CO₂ Committee on Global concentrations decade decisions dynamics Earth system ecosystems El Niño emissions energy environment fossil fuels global average Global Change Research global climate Global Environmental Change global warming greenhouse effect greenhouse gases hearing human activities impacts important improved increase integrated interactions Intergovernmental Panel IPCC issue KENNEL land long-term measurements National Academy National Research Council natural Niño Northern Hemisphere observing system ozone Panel on Climate past physical planet ppmv prediction problem processes projected question radiative forcing regional Research Foci response ROHRABACHER role scale scenarios scientists sea ice sea level simulations spatial strategy studies SUMMARY FOR POLICYMAKERS surface temperature terrestrial Thank thermohaline circulation Third Assessment Report tion U.S. Global Change uncertainty understanding