Diagnostic study of climate feedback processes in atmospheric general circulation models
Journal Article
·
· Journal of Geophysical Research
- State Univ. of New York, Stoney Brook, NY (United States)
- National Center for Atmospheric Research, Boulder, CO (United States)
A method is proposed to diagnose climate feedbacks of water vapor, temperature lapse-rate, and cloud variations in atmospheric general circulation models. It is then applied to study differences in sensitivity of the National Center for Atmospheric Research community climate model (CCM2) and two hybrid versions of CCM2 with different cumulus-convection schemes. Water vapor feedback and temperature lapse-rate feedback differ among the models due to different efficiencies of heat and moisture transport by cumulus convections. A large compensation occurs between water vapor feedback and temperature lapse-rate feedback. This leads to similar clear-sky sensitivities in the models. Cloud-radiative feedback is negative in CCM2 with a {delta}SST climate change due to the vigorous cumulus-convective scheme. Stronger convection warms the upper troposphere and reduces its cloudiness more, resulting in negative longwave cloud-radiative feedback. In models where a moist-adiabatic-adjustment scheme and then a decoupling of the atmospheric boundary layer are subsequently used, intensity of cumulus convection is successively reduced and cloud-radiative feedback changes to either neutral or positive. 31 refs., 21 figs., 21 tabs.
- OSTI ID:
- 160009
- Journal Information:
- Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: D3 Vol. 99; ISSN JGREA2; ISSN 0148-0227
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cloud radiation forcings and feedbacks: General circulation model tests and observational validation
Effects of observationally validated cloud-radiation schemes in a general circulation model
Cumulus convection parameterization and numerical modelling of moist atmospheres
Journal Article
·
Wed Oct 01 00:00:00 EDT 1997
· Journal of Climate
·
OSTI ID:588613
Effects of observationally validated cloud-radiation schemes in a general circulation model
Conference
·
Fri Oct 31 23:00:00 EST 1997
·
OSTI ID:535490
Cumulus convection parameterization and numerical modelling of moist atmospheres
Thesis/Dissertation
·
Tue Dec 31 23:00:00 EST 1991
·
OSTI ID:6927377