Evaluation and Application of the ETA Adjoint Model

小行星9626380 国家科学基金会和国家海洋和大气 美国国家海洋和大气管理局（NOAA）已经建立了一个联合计划，以支持共同感兴趣的研究。 一般来说，该计划支持的研究涉及有趣的研究工作，满足NOAA的需求，以及可以从NOAA国家环境预测中心的资源和计算机模型中受益的活动。 这项研究将得到该联合计划的支持，旨在评估和使用NOAA Eta预报模型及其在NOAA NCEP开发的相关伴随模型。 中尺度Eta模式的持续发展使得有可能评估以前没有充分记录的中尺度天气现象，特别是在美国西部，那里的中尺度大气运动与底层复杂地形紧密耦合。首席研究员将建立和扩大目前正在进行的研究，并继续评估美国西部的中尺度埃塔模式的性能。 Eta模式的伴随模式是NCEP为应用四维变分（4DVAR）资料同化而开发的。 4DVAR同化已被证明在几个案例研究，导致改进的预报技巧Eta模式预测。 随着这一数据同化程序开始在NCEP进行例行测试，将向模式开发人员并最终向业务人员提供关于模式预报对初始观测误差和其他因素的敏感性的更多信息。 拟议工作的主要目标是参与埃塔伴随模式和相关数据同化方法的开发和应用。 具体而言，作为数据同化方法的一部分获得的初始条件和伴随灵敏度的解决方案将作为不同天气情况的函数进行评估。 ***

9626380 Horel The National Science Foundation and the National Oceanic and Atmospheric Administration (NOAA) have established a joint program to support research of mutual interest. Generally, research supported under this program involves activities that are interesting research efforts, address a need of NOAA, and ones that can benefit from the resources and computer models of the NOAA National Center for Environmental Predictions. This research will be supported under this joint program and is aimed at evaluating and using the NOAA Eta forecast model and its associated adjoint model that have been developed at the NOAA NCEP. The ongoing development of the mesoscale Eta model makes it possible to evaluate mesoscale weather phenomena that have not been adequately documented before, especially in the western United States, where mesoscale atmospheric motions are tightly coupled to the underlying complex terrain. The Principal Investigator will build and expand on research underway now and continue to evaluate the performance of the mesoscale Eta modal over the Western United States. The adjoint of the Eta model has been developed at NCEP for using an advanced data assimilation method know as 4-dimensional variational (4DVAR) data assimilation. 4DVAR assimilation has been shown in several case studies to lead to improved forecast skill for Eta model forecasts. As this data assimilation procedure begins to be tested on a routine basis at NCEP, additional information will be available to model developers and, eventually, operational personnel regarding the sensitivity of the model forecasts to initial observational error and other factors. The major goal of the proposed work is to participate in the development and application of the Eta adjoint model and associated data assimilation methods. Specifically, the solutions in terms of both the initial conditions and adjoint sensitivities obtained as part of the data assimilation method will be evalua ted as a function of differing synoptic situations. ***