By scattering and absorption processes aerosols can have a significant impact on the Earth's radiation budget. To study the direct effect of aerosols on atmospheric radiative transfer the Tropospheric Aerosol Radiative FOrcing eXperiment, TARFOX, was conducted in July 1996 off the east coast of the USA. Using a variety of airborne and surface instruments measurements were made of the radiative, physical and chemical properties of the aerosol, with the intention of performing internal and external column closure experiments.
The UK Meteorological Office Meteorological Research Flight C130 aircraft was able to make measurements of the shortwave upwelling irradiance and the downwelling direct and diffuse irradiances in cloud-free conditions over a range of total column aerosol loadings and over the depth of the aerosol layers. These data cover the 0.3 to 3.0 micron and 0.7 to 3.0 micron wavelength ranges and are used to calculate the visible column optical depth and the direct radiative forcing induced by the aerosol.
Measurements were also made of the accumulation mode aerosol size spectra; the single scatter optical properties of the aerosol are calculated for input to a shortwave radiative transfer model which is used to calculate the expected forcing for comparison with the observations.
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Last updated Apr-30-1997
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