Observed screen (air) and GCM surface/screen temperatures: Implications for outgoing longwave fluxes at the surface

Journal Article · Mon May 01 04:00:00 EDT 1995 · Journal of Climate

DOI:https://doi.org/10.1175/1520-0442(1995)008<1360:OSAGST>2.0.CO;2· OSTI ID:95959

Garratt, J R ^[1]

---

1. CSIRO Division of Atmospheric Research, Aspendale, Victoria (Australia)

There is direct evidence that excess net radiation calculated in general circulation models at continental surfaces (of about 11-17 W m{sup -2} (20%-27%) on an annual basis) is not only due to overestimates in annual incoming shortwave fluxes of 9-18 W m{sup -2} (6%-9%), but also to underestimates in outgoing longwave fluxes. THe bias in the outgoing longwave flux is deduced from a comparison of screen-air temperature observations, available as a global climatology of mean monthly values, and model-calculated surface and screen-air temperatures. An underestimate in the screen temperature computed in general circulation models over continents, of about 3 K on an annual basis, implies an underestimate in the outgoing longwave flux, averaged in six models under study, of 11-15 W m{sup -2} (3%-4%). For a set of 22 inland stations studied previously, the residual bias on an annual basis (the residual is the net radiation minus incoming shortwave plus outgoing longwave) varies between 18 and -23 W m{sup -2} for the models considered. Additional biases in one or both of the reflected shortwave and incoming longwave components cannot be ruled out. 13 refs., 3 figs., 5 tabs.

• OSTI ID: 95959
• Journal Information: Journal of Climate, Journal Name: Journal of Climate Journal Issue: 5 Vol. 8; ISSN JLCLEL; ISSN 0894-8755
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ACCURACY
CALCULATION METHODS
GENERAL CIRCULATION MODELS
RADIANT HEAT TRANSFER
SURFACE AIR