Chapter 1: INTRODUCTION
latitudes, according to Payne (1972), mean values of albedo can be as high
as 44%, while Budyko (1963) suggested values that do not exceed 23%.
The radiative models considered above treat radiative transfer in the
atmosphere and ocean separately, often by regarding one medium as a
boundary condition for the other. Coupled atmosphere-ocean radiative
transfer models treat absorption and scattering by layers for both the
atmosphere and the ocean explicitly and consistently. Such models are
capable of more accurately calculating radiative flux and albedo over the
ocean surface based on the optical properties of the atmosphere and ocean
(Jin et al., 2002). The key input parameters in the Jin et al. (2002) model are
aerosol optical depth, surface wind speed, and total precipitation water from
in situ measurements. According to the results of the field test shown in
Figure 1-8, the mean model-observation differences for the ocean surface
albedo are generally less than 1%. Sensitivity tests conducted by Jin et al.
(2002) indicate that the incorporation of scattering effects by air bubbles
and/or suspended material into the algorithms has the potential to further
reduce the model-observation differences in the ocean surface albedo.
29
Figure 1-8. Model-observation comparison for the sea surface albedo A as a function of solar
zenith angle T at a site 25 km east of Virginia in the Atlantic Ocean for 3 months from June
to August 2000. The mean difference between model and observations is 0.44%; standard
deviation is 0.34%. Adapted from Jin et al. (2002) by permission of American
Meteorological Society.
latitudes, according to Payne (1972), mean values of albedo can be as high
as 44%, while Budyko (1963) suggested values that do not exceed 23%.
The radiative models considered above treat radiative transfer in the
atmosphere and ocean separately, often by regarding one medium as a
boundary condition for the other. Coupled atmosphere-ocean radiative
transfer models treat absorption and scattering by layers for both the
atmosphere and the ocean explicitly and consistently. Such models are
capable of more accurately calculating radiative flux and albedo over the
ocean surface based on the optical properties of the atmosphere and ocean
(Jin et al., 2002). The key input parameters in the Jin et al. (2002) model are
aerosol optical depth, surface wind speed, and total precipitation water from
in situ measurements. According to the results of the field test shown in
Figure 1-8, the mean model-observation differences for the ocean surface
albedo are generally less than 1%. Sensitivity tests conducted by Jin et al.
(2002) indicate that the incorporation of scattering effects by air bubbles
and/or suspended material into the algorithms has the potential to further
reduce the model-observation differences in the ocean surface albedo.
29
Figure 1-8. Model-observation comparison for the sea surface albedo A as a function of solar
zenith angle T at a site 25 km east of Virginia in the Atlantic Ocean for 3 months from June
to August 2000. The mean difference between model and observations is 0.44%; standard
deviation is 0.34%. Adapted from Jin et al. (2002) by permission of American
Meteorological Society.