Ten year radiation budget of the Earth: 1984–93

Abstract

A 10 year climatology is given of the global distributions of net shortwave (SW), net longwave (LW) and net all-wave radiation budget at both top-of-atmosphere (TOA) and at the Earth's surface, on a mean monthly basis, computed with a radiative transfer model with input data for key atmospheric and surface parameters. The model input data were taken from complete and comprehensive global climatological data sets, such as the International Satellite Cloud Climatology Project, the National Centers for Environmental Prediction and National Center for Atmospheric Research Global Reanalysis or the TIROS Operational Vertical Sounder, among others. Seasonal and latitudinal variations and mean annual and mean hemispherical and global averages are given, based on model results computed for each month of the period from January 1984 to December 1993. At TOA, the net incoming SW radiation has larger latitudinal variation and range of values (0-400 W m −2 ) than the outgoing LW radiation (100-350 W m −2 ). At the surface, the net downward SW radiation has similar features to that at TOA, but with smaller magnitudes. The net upward LW radiation is quite different than at TOA, with a smaller seasonal and geographical variability than the surface net SW radiation. The global system of Earth-atmosphere is found to be net radiatively heated at TOA by 3 W m −2 ; the Earth's surface is net heated by 98 W m −2 , mainly due to solar absorption equal to 147 W m −2 , a value in agreement with surface-based measurements. At TOA, there is a radiative energy surplus between 40°S and 30°N and a radiative loss poleward; however, at the surface the surplus regions extend from 70°S to 70°N. Globally, the atmosphere is found to absorb 27% of the incoming solar radiation at TOA, while it emits 79% of the outgoing terrestrial radiation.

Daily cycle of the surface energy balance in Antarctica and the influence of clouds

“…The annual mean surface net radiation balance over the ice sheet of Antarctica is negative on average (Hatzianastassiou et al, 2004;Van den Broeke et al, 2004c), which leads to cooling of the near-surface air and a well-developed katabatic circulation. Under the influence of Coriolis forcing, Antarctic katabatic winds flow generally eastwards along the height contours of the ice sheet and are therefore sensitive to the strength of the mid-tropospheric westerlies (i.e.…”

An assessment of radiation budget data provided by the ISCCP and GEWEX‐SRB

“…These data‐series are available since several years as grid averages on the respective websites of both projects. They found already worldwide use to study the time and space pattern of fields of the radiation fluxes and the vertical flux divergence inclusive the effect of cloud fields on them [e.g., Raschke et al , 2005a] or to validate related products computed in separated projects [e.g., Hatzianastassiou et al , 2004] or by general circulation models [e.g., Gates et al , 1999; Jakob , 2004]. The data‐sets used here remained unchanged at least until about June 2005.…”

Spatial and temporal distribution of long‐term short‐wave surface radiation over Greece

“…It has been also used by Hatzianastassiou et al (2004b) to compute the 10-year (1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994) global distribution of net SW radiation budget at the TOA and at the surface, and by Fotiadi et al (2005) to study trends in tropical mean SW radiation budget at TOA.…”

“…Other versions have been used by Vardavas and Koutoulaki (1995), and Vardavas (1999, 2001) to compute the SW SRB of the northern and southern hemispheres on a mean-monthly and 10 • latitude zonal basis. It has been also used by Hatzianastassiou et al (2004b) to compute the 10-year (1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994) global distribution of net SW radiation budget at the TOA and at the surface, and by Fotiadi et al (2005) to study trends in tropical mean SW radiation budget at TOA.…”