Determination of Parameters of the Atmosphere and the Surface in a Clear Atmosphere - Short-Wave Solar Radiation in the Earth's Atmosphere - page 199

Fig. 5.10a,b. Results of the retrieval of the spectral dependence of the surface albedo: a from
the data of the airborne sounding 16th October 1983 above the Kara-Kum Desert, sand
surface; b from the data of the airborne sounding 29th April 1985 above Ladoga Lake, snow
surface. Dashed lines indicate the relevant profiles of the a priori models

[consequence 4 from (4.38)]. However, the digitizing of the signal during the
observations with the K-3 instrument has been accomplishedwith an accuracy
to 10 binary, i. e. 3 decimal orders. This means that after averaging the results
of about 100 measurements the accuracy of the mean value could exceed the
accuracy of the instrument signal registration (Otnes and Enochson 1978). The
ratio about 1 | 100 appears between the number of the independent retrieved

parameters (during the transformation to the basis of the a priori covariance
matrix)andthenumberofobservations.Certainlynotonlytheaveragingbut
more complicated data processing is carried out during the inverse problem
solving, but it does not matter and the obtained SD of the retrieved parameters
could turn out lower than the real values. Especially it appears during the
surface spectral albedo retrieval because all observational results are used in
this case and the spectral albedo is described with only several independent
parameters owing to its strong autocorrelation. Therefore, the formal accuracy
of the albedo retrieval turns out fantastically high. However, in reality, the