The impacts of cloud-radiative changes on poleward atmospheric and oceanic energy transport in a warmer climate
Journal
Journal of Climate
Journal Volume
34
Journal Issue
19
Pages
7857-7874
Date Issued
2021
Author(s)
Abstract
Based on theory and climate model experiments, previous studies suggested that most of the uncertainties in projected future changes in meridional energy transport and zonal mean surface temperature can be attributed to cloud feedback. To investigate how radiative and dynamical adjustments modify the influence of cloud-radiative changes on energy transport, this study applies a cloud-locking technique in a fully coupled climate model, CESM. Under global warming, the impacts of cloud-radiative changes on the meridional energy transport are asymmetric in the two hemispheres. In the Northern Hemisphere, the cloud-radiative changes have little impact on energy transport because 89% of the cloud-induced heating is balanced locally by increasing outgoing longwave radiation. In the Southern Hemisphere, on the other hand, cloud-induced dynamical changes in the atmosphere and the ocean cause enhanced poleward energy transport, accounting for most of the increase in energy transport under warming. Our experiments highlight that the local longwave radiation adjustment induced by temperature variation can partially offset the impacts of cloud-radiative changes on energy transport, making the estimated impacts smaller than those obtained from directly integrating cloud-radiative changes in previous studies. It is also demonstrated that the cloud-radiative impacts on temperature and energy transport can be significantly modulated by the oceanic circulation, suggesting the necessity of considering atmospheric-oceanic coupling when estimating the impacts of cloud-radiative changes on the climate system. ? 2021 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).
Subjects
Climate change
Cloud radiative effects
Energy transport
Atmospheric movements
Atmospheric temperature
Global warming
Long-wave radiation
Northern Hemispheres
Oceanic circulations
Outgoing longwave radiation
Poleward energy transport
Southern Hemisphere
Surface temperatures
Temperature variation
Climate models
climate modeling
cloud radiative forcing
global warming
heating
Northern Hemisphere
surface temperature
uncertainty analysis
zonal flow
SDGs
Type
journal article