Cloud-radiative forcing and climate: Results from the earth radiation budget experiment

Journal Article · Fri Jan 06 04:00:00 EST 1989 · Science (Washington, D.C.); (USA)

DOI:https://doi.org/10.1126/science.243.4887.57· OSTI ID:6372425

Ramanathan, V; Ahmad, E ^[1]; Cess, R D ^[2]; Harrison, E F; Minnis, P; Barkstrom, B R ^[3]; Hartmann, D ^[4]

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1. Univ. of Chicago, IL (USA)
2. State Univ. of New York, Stony Brook (USA)
3. NASA Langley Research Center, Hampton, VA (USA)
4. Univ. of Washington, Seattle (USA)

Quantitative estimates of the global distributions of cloud-radiative forcing have been obtained from the spaceborne Earth Radiation Budget Experiment (ERBE) launched in 1984. For the April 1985 period, the global shortwave cloud forcing ({minus}44.5 watts per square meter (W/m{sup 2})) due to the enhancement of planetary albedo, exceeded in magnitude the longwave cloud forcing (31.3 W/m{sup 2}) resulting from the greenhouse effect of clouds. Thus, clouds had a net cooling effect on the earth. This cooling effect is large over the mid- and high-latitude oceans, with values reaching {minus}100 W/m{sup 2}. The monthly averaged longwave cloud forcing reached maximum values of 50 to 100 W/m{sup 2} over the convectively disturbed regions of the tropics. However, this heating effect is nearly canceled by a correspondingly large negative short-wave cloud forcing, which indicates the delicately balanced state of the tropics. The size of the observed net cloud forcing is about four times as large as the expected value of radiative forcing from a doubling of CO{sub 2}. The shortwave and longwave components of cloud forcing are about ten times as large as those for a CO{sub 2} doubling. Hence, small changes in the cloud-radiative forcing fields can play a significant role as a climate feedback mechanism.

• OSTI ID: 6372425
• Journal Information: Science (Washington, D.C.); (USA), Journal Name: Science (Washington, D.C.); (USA) Vol. 243:4887; ISSN SCIEA; ISSN 0036-8075
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ALBEDO
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CLIMATES
CLOUDS
ENVIRONMENTAL EFFECTS
GLOBAL ASPECTS
GREENHOUSE EFFECT
OXIDES
OXYGEN COMPOUNDS
VARIATIONS