Tuesday, 13 January 2009: 8:30 AM
Comparisons of Cloud Water Content between CloudSat Estimates and ECMWF Analyses over Asian Monsoon Region and Tibet
Room 129A (Phoenix Convention Center)
Cloud water content (CWC) estimates from CloudSat over south Asian monsoon and Tibet regions, including vertically-resolved liquid (LWC) and ice water (IWC) are described for the period of June, July and August (JJA) 2006. Comparisons are also made with ECMWF analyses. Overall, at and above the 600 hPa level, the total IWC from CloudSat are a factor of 2~3 larger than the ECMWF analyses. The peak values in the CloudSat IWC occur over Bay of Bengal, eastern and western sides of Tibet regions; these features are not as evident in the analyses. Better agreement is found between the analyses and CloudSat IWC when retrievals flagged composed of convective clouds or indicating surface precipitation are excluded. The analysis values closely resemble the CloudSat LWC estimates in terms of overall morphology, although the analysis values are slightly smaller than the CloudSat values, in particular over western Tibet and at/above 500hPa. There appears to be an upward and northward advection of LWC crossing central Tibet Plateau from the Indian Monsoon region evident in the CloudSat LWC but not as evident in the analyses. The contributions of LWC/IWC are mainly associated with deep cumulus, altocumulus, altostratus and Nimbostratus over the Tibetan Plateau while the stratocumulus clouds occurrence are found along the Tibet foothill regions and on top of eastern Plateau. The issues of representing CWC and precipitation consistently between satellite-derived and model values are also discussed.