Progress and Strategies of the Joint OSSE at NOAA and JCSDA

An international collaborative effort for Observing System Simulation Experiments (OSSE) was developed over the last few years. Although a large initial investment is required for an OSSE, using an OSSE is the most reliable strategy today to assess the quantitative impact from prospective observing systems. The first 13 month long Joint OSSE Nature Run was produced by the European Center for Medium-Range Weather Forecasts (ECMWF) and shared with the internationally collaborative Joint OSSE community. A Nature Run for the period from May 2005 to May 2006 was produced using the real analysis on May 1, 2005 as the initial condition and using observed daily SST and ice. A simulation of basic observations for control experiments was completed by the National Centers for Environmental Prediction (NCEP) and Joint Center for Satellite and Data Assimilation (JCSDA and shared with the Joint OSSE community.

The first OSSE conducted at JCSDA focused on an evaluation of the space based Doper Wind Lidar (DWL), which is a costly observing system providing three dimensional global wind profiles. The OSSE results showed a significant improvement in both intensity and track for hurricane forecasts. OSSEs to evaluate the relative impact between model resolution and DWL were conducted. The results showed a significant improvement in both intensity and track for hurricane forecast with DWL at all model resolutions. The results also showed that the forecast impact depends on the scale of an event.

Now the basic observing system is being upgraded to 2012 observing systems. Further applications of OSSE to evaluate various future observing systems, an OSSE on the Optical Autocovariance Wind Lidar (OAWL), and alternative configurations of existing satellite systems such as a satellite system in early-morning-orbit, and the future Arctic Observing Network (AON) are being discussed.