The aircraft will be deployed from sites in Hawaii, Christmas Island, Tahiti, American Samoa, Easter Island, and Fiji to cover an area ranging roughly from the Cook Islands to the west coast of South America. Over 30 principal investigators from 17 U.S. universities and research laboratories are involved in the experiment. They found significant levels of human-generated pollution, primarily from fires set to clear land for agriculture in Africa and possibly South America. PEM-Tropics B is returning during the wet season, when the impact of biomass burning in the Southern Hemisphere is expected to be much lower. The ability of sulfate aerosols to reflect the sun's radiation may be one reason that increasing greenhouse gases have not warmed the earth as much as some climate models have predicted.
Sulfates also contribute to local pollution and acid rain.
While the sources of tropospheric ozone include biomass burning and urban smog, this trace gas is also involved in the oxidizing process. Understanding the life cycle of ozone in the troposphere is vital to understanding the oxidizing capacity of the atmosphere. He'll provide twice-weekly updates on what it's like to do science over the South Pacific. NCAR is managed by the University Corporation for Atmospheric Research, a consortium of more than 60 universities offering Ph.D.s in atmospheric and related sciences.