Sensitivity of CAM5-Simulated Arctic Clouds and Radiation to Ice Nucleation ParameterizationSource: Journal of Climate:;2013:;volume( 026 ):;issue: 016::page 5981DOI: 10.1175/JCLI-D-12-00517.1Publisher: American Meteorological Society
Abstract: ensitivity of Arctic clouds and radiation in the Community Atmospheric Model, version 5, to the ice nucleation process is examined by testing a new physically based ice nucleation scheme that links the variation of ice nuclei (IN) number concentration to aerosol properties. The default scheme parameterizes the IN concentration simply as a function of ice supersaturation. The new scheme leads to a significant reduction in simulated IN concentration at all latitudes while changes in cloud amounts and properties are mainly seen at high- and midlatitude storm tracks. In the Arctic, there is a considerable increase in midlevel clouds and a decrease in low-level clouds, which result from the complex interaction among the cloud macrophysics, microphysics, and large-scale environment. The smaller IN concentrations result in an increase in liquid water path and a decrease in ice water path caused by the slowdown of the Bergeron?Findeisen process in mixed-phase clouds. Overall, there is an increase in the optical depth of Arctic clouds, which leads to a stronger cloud radiative forcing (net cooling) at the top of the atmosphere. The comparison with satellite data shows that the new scheme slightly improves low-level cloud simulations over most of the Arctic but produces too many midlevel clouds. Considerable improvements are seen in the simulated low-level clouds and their properties when compared with Arctic ground-based measurements. Issues with the observations and the model?observation comparison in the Arctic region are discussed.
|
Collections
Show full item record
contributor author | Xie, Shaocheng | |
contributor author | Liu, Xiaohong | |
contributor author | Zhao, Chuanfeng | |
contributor author | Zhang, Yuying | |
date accessioned | 2017-06-09T17:07:14Z | |
date available | 2017-06-09T17:07:14Z | |
date copyright | 2013/08/01 | |
date issued | 2013 | |
identifier issn | 0894-8755 | |
identifier other | ams-79682.pdf | |
identifier uri | http://onlinelibrary.yabesh.ir/handle/yetl/4222489 | |
description abstract | ensitivity of Arctic clouds and radiation in the Community Atmospheric Model, version 5, to the ice nucleation process is examined by testing a new physically based ice nucleation scheme that links the variation of ice nuclei (IN) number concentration to aerosol properties. The default scheme parameterizes the IN concentration simply as a function of ice supersaturation. The new scheme leads to a significant reduction in simulated IN concentration at all latitudes while changes in cloud amounts and properties are mainly seen at high- and midlatitude storm tracks. In the Arctic, there is a considerable increase in midlevel clouds and a decrease in low-level clouds, which result from the complex interaction among the cloud macrophysics, microphysics, and large-scale environment. The smaller IN concentrations result in an increase in liquid water path and a decrease in ice water path caused by the slowdown of the Bergeron?Findeisen process in mixed-phase clouds. Overall, there is an increase in the optical depth of Arctic clouds, which leads to a stronger cloud radiative forcing (net cooling) at the top of the atmosphere. The comparison with satellite data shows that the new scheme slightly improves low-level cloud simulations over most of the Arctic but produces too many midlevel clouds. Considerable improvements are seen in the simulated low-level clouds and their properties when compared with Arctic ground-based measurements. Issues with the observations and the model?observation comparison in the Arctic region are discussed. | |
publisher | American Meteorological Society | |
title | Sensitivity of CAM5-Simulated Arctic Clouds and Radiation to Ice Nucleation Parameterization | |
type | Journal Paper | |
journal volume | 26 | |
journal issue | 16 | |
journal title | Journal of Climate | |
identifier doi | 10.1175/JCLI-D-12-00517.1 | |
journal fristpage | 5981 | |
journal lastpage | 5999 | |
tree | Journal of Climate:;2013:;volume( 026 ):;issue: 016 | |
contenttype | Fulltext |