Climatic effects of atmospheric aerosols
Source: dust and Environmental Research Laboratory
The influence of aerosol on climate system is divided into direct radiative forcing and indirect radiative forcing. Direct radiative forcing is refers to the particles through absorption and scattering longwave and shortwave radiation, thus changing the radiation balance of the earth atmosphere system; atmospheric particulate matter as cloud condensation nuclei or ina change cloud microphysical and optical properties and precipitation efficiency, and thus indirectly affect climate, known as indirect radiative forcing.
Sketch map of climate system change process
Current global change and Atmospheric Chemistry Study on the disturbance of highly focused aerosols on the earth's climate system, especially the radiative forcing of carbon aerosols (Aerosol Carbonaceous). Carbon aerosols in the atmosphere usually include organic carbon (carbon organic, OC carbon EC, element) (or black carbon, carbon black, graphite carbon, carbon graphite). EC single direct drive factor, has become a global atmospheric system after CO2 increase temperature group, EC in the study of global radiation balance is an important parameter. In some areas, the EC can be caused by aerosol radiative forcing change from the negative effects of radiation to positive radiative effect, resulting in a net warming effect. Since 1880, the global temperature rise of 25% can be attributed to EC. In recent years, the release of OC and EC in China has attracted the attention of scientists at home and abroad. Cooke estimates for global emissions to EC quarter from China; EC limits on emissions is considered to be the current slowdown in the global climate warming is one of the effective ways, the main group of high concentrations of OC and EC is urban atmospheric particulate matter. At the regional scale, EC is considered to be a significant driving factor of regional climate change in China, which has accelerated the trend of drought in South China in recent years.
Since the 70's of last century, some people began to notice the climate effect of aerosol. 1971 Rasool and Schneider proposed: if the global aerosol background concentration increased by 4 times, the average temperature will be reduced by 3.5. However, the global warming phenomenon has been followed by the aerosol climate effect. Until 1991 the Philippines Pinatu Bo (Pinatubo) volcanic eruption, large amounts of dust and sulfate aerosols into the atmosphere, the global average temperature, a decrease of 0.5 DEG C, the effect of aerosol on climate is also cause for concern. Major scientific issues in the study of atmospheric aerosols and their impacts on climate change is the frontier and focus of atmospheric science and global change research.
