Observation impact over the southern polar area during the Concordiasi field campaign
Observation impact over the southern polar area during the Concordiasi field campaign
复制标题
康科迪亚西野外活动期间对南极地区的观测影响
DOI：
10.1002/qj.2470
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发表时间：
2016
影响因子：
8.9
通讯作者：
A. Doerenbecher
中科院分区：
文献类型：
--
作者：
Nathalie Boullot;F. Rabier;R. Langland;R. Gelaro;C. Cardinali;V. Guidard;P. Bauer;A. Doerenbecher
在Concordisi现场实验时，研究了2010年春季南极地区四个不同系统（NRL，GMAO，ECMWF和Météo-France）观测对分析不确定性和预报性能的影响。500 hPa高度分析中最大的多模式方差出现在南亚南极海洋区域，那里有快速演变的天气系统，快速的预报误差增长，以及较少的高空风观测数据来限制分析。所有观测值对模型预测的总影响使用24小时预测对观测值的敏感性诊断来计算。对减少预报误差贡献最大的观测类型是AMSU、IASI、AIRS、GPS-RO、无线电探空仪、地面和大气运动矢量观测。关于探测数据、无线电探空仪和下投式探空仪，人们可以注意到，它们对低层温度的分析和预报有很大影响，对高层风有很大影响。使用Concordiasi投下式探空仪的观测系统实验表明，在南极高原上的观测对低纬度地区的预报范围有很大的影响，最大影响在50-70°S附近。这些实验表明，更好地利用陆地和海冰上的辐射数据以及从各种卫星组合获得的创新大气运动矢量可以填补当前的数据空白并改善该地区的数值天气预报分析。
The impact of observations on analysis uncertainty and forecast performance was investigated for austral spring 2010 over the southern polar area for four different systems (NRL, GMAO, ECMWF and Météo‐France) at the time of the Concordiasi field experiment. The largest multi‐model variance in 500 hPa height analyses is found in the southern sub‐Antarctic oceanic region, where there are rapidly evolving weather systems, rapid forecast‐error growth, and fewer upper‐air wind observation data to constrain the analyses. The total impact of all observations on the model forecast was computed using the 24 h forecast sensitivity‐to‐observations diagnostic. Observation types that contribute most to the reduction of the forecast error are shown to be AMSU, IASI, AIRS, GPS‐RO, radiosonde, surface and atmospheric motion vector observations. For sounding data, radiosondes and dropsondes, one can note a large impact on the analysis and forecasts of temperature at low levels and a large impact of wind at high levels. Observing system experiments using the Concordiasi dropsondes show a large impact of the observations over the Antarctic plateau extending to lower latitudes with the forecast range, with the largest impact around 50–70°S. These experiments indicate there is a potential benefit from using radiance data better over land and sea‐ice and from innovative atmospheric motion vectors obtained from a combination of various satellites to fill the current data gaps and improve numerical weather prediction analyses in this region.