Arctic cloud annual cycle biases in climate models

• DOI: 10.5194/acp-2018-1159
• Publication Date: 2018-12-21T14:53:37Z
• Authors: Patrick C. Taylor; Robyn C. Boeke; Ying Li; David W. J. Thompson
• Keywords: Cloud forcing; Liquid water content

Abstract. Arctic clouds exhibit a robust annual cycle with maximum cloudiness in fall and minimum winter. These variations affect energy flows the large influence on surface radiative fluxes. Contemporary climate models struggle to reproduce observed cloud amount significantly disagree each other. The goal of this analysis is quantify influencing factors that contribute winter-summer differences, as these seasons are primarily responsible for model discrepancies observations. We find differences total caused by low, not high, clouds; largest occur between 950 hPa. Stratifying factors, we groups most under strong lower tropospheric stability, weak moderate mid-tropospheric subsidence, cold air temperatures. Inter-group low found be function dependence thermodynamic characteristics. larger winter produce more ice, whereas summer liquid. Thus, parameterization ice microphysics, specifically formation mechanism (deposition vs. immersion freezing) liquid partitioning, contributes inter-model provides further evidence important role microphysical processes play evolution modeling system.