Wind shear effects on cloud-radiation feedback in the western Pacific warm pool
Article first published online: 31 AUG 2004
Copyright 2004 by the American Geophysical Union.
Geophysical Research Letters
Volume 31, Issue 16, August 2004
How to Cite
2004), Wind shear effects on cloud-radiation feedback in the western Pacific warm pool, Geophys. Res. Lett., 31, L16118, doi:10.1029/2004GL020199., and (
- Issue published online: 31 AUG 2004
- Article first published online: 31 AUG 2004
- Manuscript Accepted: 5 AUG 2004
- Manuscript Revised: 18 JUL 2004
- Manuscript Received: 7 APR 2004
 Upper tropospheric stratiform clouds associated with deep convection are important to global radiation budgets and to cloud-radiation feedbacks on climate variability and change. Several recent observational studies indicate that vertical wind shear is an important factor affecting stratiform cloud fraction and cloud overlap. This study further examines wind shear effects on cloud properties (including cloud fraction and cloud optical depth) and associated top of atmosphere (TOA) and surface radiative fluxes, using observations from the Tropical Ocean Global Atmosphere program's Coupled Ocean Atmosphere Response Experiment (TOGA COARE) experiment and long-term satellite measurements. Wind shear affects cloud-radiative fluxes, through both the cloud fraction and optical thickness, in a strong and systematic way. In typical convecting conditions, shear-induced additional cloudiness can reduce outgoing longwave radiation (OLR) by 10s of Wm−2, implying longwave radiative changes on the order of 10% of the total latent heating. Such cloud also reflects shortwave radiation, reducing surface downward flux (energy input to the ocean) by 10s of Wm−2. Current climate models lack these effects.