Ramanathan has served on IPCC WG2 Panels, he headed the UN's INDOEX project and he's as solid a climate scientist as we have.
Ramanathan's surprising field data found that tropospheric soot (with or without white sulfates) are causing nearly 40 percent of warming over the vast Pacific alone. Consistently the field data found 42% of the sootfall on the American West Coast was from China (75% of California 's own emissions). That's 30% of the Earth's surface, which would make for 12% of the temperature anomalies.
The way that Dr. Ramanathan's team made the discovery was not from satellite or surface data, but from flying sorties of robotic planes through brown clouds in the mid-troposphere. Much to their surprise they found that - contrary to conventional opinion - airborne soot has a net atmospheric heating effect (instead of a net cooling effect). An August 2007 news article:
Dr. Ramanathan's testimony:
Tropospheric soot has an effect that's 60% of CO2's global warming effects (around a 37/53 mix).
- Airborne soot's heating effects have been found to be 60 percent of CO2's: "…The report concludes that the atmospheric warming effect of blackcarbon pollution is as much as three to four times the consensus estimate released last year in a report by the U.N.-sponsored Intergovernmental Panel on Climate Change."
- Soot is just as important as CO2 in melting tropical glacial packs like the Himalayas
- Tropospheric soot contributes roughly 35 - 40 percent of all observed temperature anomalies (roughly a 37-57 soot-CO2 ratio).: "…black carbon [soot] pollution contributes to global warming at a level that is about 60% of carbon dioxide's warming effect.." and "…A mass of black carbon in the atmosphere causes about 300,000 timesas much instantaneous warming as the same amount of carbon dioxide."
- Ramanathan's most-recent authored paper (coauthored with G. Carmichael) appeared in Nature Geoscience 1, 221 - 227 (2008 - Published online: 23 March 2008) is titled "Global and regional climate changes due to black carbon."
V. Ramanathan @ Scripps UCSD