Characterization of ice cloud properties obtained by shipborne radar/lidar over the tropical western Pacific Ocean for evaluation of an atmospheric general circulation model
Characterization of ice cloud properties obtained by shipborne radar/lidar over the tropical western Pacific Ocean for evaluation of an atmospheric general circulation model
复制标题
热带西太平洋上空船载雷达/激光雷达获得的冰云特性特征，用于评估大气环流模型
DOI：
10.1029/2009jd012944
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
H. Kumagai and N. Sugimoto
中科院分区：
文献类型：
--
作者：
Sato;K.;H. Okamoto;T. Takemura;H. Kumagai and N. Sugimoto
本研究分析了热带西太平洋R/VMirai地区收集的95 GHz雷达/激光雷达数据，结合国际卫星云气候学项目(ISCCP)的聚类分析，描述了该地区冰云有效半径反射率、冰水含量IWC和云内垂直速度的垂直分布。从Mirai观测到的冰云与ISCCP的天气机制大致一致；对流活动越多的地区有更多的高云，由更深的云和更大的冰水路径(IWP)和降水冰块组成。然后利用雷达-激光雷达模拟器和ISCCP天气模式对气候系统研究中心、国家环境研究所、全球变化前沿研究中心的冰云微物理模式进行了评估，以比较不同尺度上的统计数据。该模式倾向于产生高云量，在卷云区域大两倍，但在最深对流区域低50%。模拟的IWP只能很弱地再现观测到的变化，而且总体上低估了观测值，尽管天气状况不同。在模拟网格中，0.1g−3附近的平均IWC太小，特别是在11公里以上。大气环流模式成功地预报了11公里以上的观测频率分布，但由于REF∼100μm的比例过大，在11公里以下的峰值产生了很大的高估。建立Ref>；120μm的云冰截止点是相当合理的，尽管它会遗漏一些观测到的较大的粒子。
This study analyzed 95‐GHz radar/lidar data collected from the R/VMiraiover the tropical western Pacific to characterize the vertical distribution of ice cloud effective radiusreff, ice water content IWC, and in‐cloud vertical velocity of the region in conjunction with weather regimes classified by International Satellite Cloud Climatology Project (ISCCP) cluster analysis. Ice clouds observed from theMiraiwere roughly consistent with the ISCCP weather regimes; more convectively active regimes had larger amounts of high cloud consisting of deeper cloud with larger ice water path (IWP) and precipitating ice fraction. Ice cloud microphysics of the Center for Climate System Research, National Institute for Environmental Studies, Frontier Research Center for Global Change atmospheric general circulation model (AGCM) was then evaluated using the radar–lidar simulator and ISCCP weather regimes for comparison of the statistics at different scales. The model tended to produce a high cloud fraction that was two times larger in the cirrus regimes but 50% lower in the deepest convective regime. The simulated IWP could only weakly reproduce the observed variety and generally underestimated the observed values despite the weather regimes. Cutoff in the simulated grid mean IWC around 0.1 g−3was too small, especially above 11 km. The AGCM successfully predicted the observed frequency distribution forreffabove 11 km, but produced large overestimation in the peak value below 11 km due to the excessively large fraction ofreff∼100μm. Establishing a cutoff for cloud ice atreff> 120μm was found to be quite reasonable, although it would miss some of the larger particles that were observed.