Effects of total solar eclipse of 29 March 2006 on surface radiation

[摘要] Solar irradiance spectral measurements were performed during a total solareclipse. The spectral effect of the limb darkening to the global, directirradiance and actinic flux measurements was investigated. This effect leadsto wavelength dependent changes in the measured solar spectra showing a muchmore pronounced decrease in the radiation at the lower wavelengths.Radiative transfer model results were used for the computation of acorrection for the total ozone measurements due to the limb darkening. Thiscorrection was found too small to explain the large decrease in total ozonecolumn derived from the standard Brewer measurements, which is an artifactin the measured irradiance due to the increasing contribution of diffuseradiation against the decreasing direct irradiance caused by the eclipse.Calculations of the Extraterrestrial spectrum and the effective sun'stemperatures, as measured from ground based direct irradiance measurements,showed an artificial change in the calculations of both quantities due tothe fact that radiation coming from the visible part of the sun during theeclipse phases differs from the black body radiation described by thePlanck's law.

[学科分类] 大气科学