Climate Science has repeatedly reported that the attribution of the radiative effect of CO2 to global warming is significantly overstated; e.g. see
and my powerpoint talk
Pielke, R.A. Sr., 2006: Regional and Global Climate Forcings. Presented at the Conference on the Earth’s Radiative Energy Budget Related to SORCE, San Juan Islands, Washington, September 20-22, 2006.
Now there is a new paper by V. Ramanathan and Greg Carmichael to appear on March 23 in Nature Geoscience titled “Global and regional climate changes due to black carbon” [and thanks to Jos de Laat for alerting us to it!].
The Scripps news release which announces this is titled “Black Carbon Polluition Emerges as Major Player in Global Warming”.
The report writes that
“…. soot and other forms of black carbon could have as much as 60 percent of the current global warming effect of carbon dioxide, more than that of any greenhouse gas besides CO2″
“In the paper, Ramanathan and Carmichael integrated observed data from satellites, aircraft and surface instruments about the warming effect of black carbon and found that its forcing, or warming effect in the atmosphere, is about 0.9 watts per meter squared. That compares to estimates of between 0.2 watts per meter squared and 0.4 watts per meter squared that were agreed upon as a consensus estimate in a report released last year by the Intergovernmental Panel on Climate Change (IPCC), a U.N.-sponsored agency that periodically synthesizes the body of climate change research. “
and
“Ramanathan and Carmichael said the conservative estimates are based on widely used computer model simulations that do not take into account the amplification of black carbon’s warming effect when mixed with other aerosols such as sulfates. The models also do not adequately represent the full range of altitudes at which the warming effect occurs. The most recent observations, in contrast, have found significant black carbon warming effects at altitudes in the range of 2 kilometers (6,500 feet), levels at which black carbon particles absorb not only sunlight but also solar energy reflected by clouds at lower altitudes.”
Ramanthan is quoted as saying
”‘We now have to examine if black carbon is also having a large role in the retreat of arctic sea ice and Himalayan glaciers as suggested by recent studies.’”
Climate Science (and the 2005 National Research Council report Radiative forcing of climate change: Expanding the concept and addressing uncertainties) have urged that the policy community move beyond their myopic view of global warming and this study will hopefully encourage them them to broaden their view.