Data Denial Experiments and Observing System Simulation Experiments with Radio Occultation Observations

Observing System Simulation Experiments (OSSEs) are being conducted in support of NOAA's Data Gap Mitigation activities. One observing system of particular importance is GNSS (Global Navigation Satellite Systems) RO (Radio Occultation). The assimilation of RO observations into global data assimilation systems has been shown to provide significant improvement in weather forecast skill worldwide. So far, no saturation has been reached in prediction skill with the current RO constellation. Consequently, politicians and scientists are wondering how much would future RO constellations mitigate a delay in the launch of JPSS-1.

As part of the US global OSSE effort, under the leadership of NOAA OAR and JCSDA, ESRL is planning to run GNSS RO OSSEs. Both, commercial (i.e. data sale) and non-commercial options will be investigated. More specifically, we are considering COSMIC-2, GeoOptics and PlanetIQ approaches.

In addition and in support of these OSSE activities, a series of Observing System Experiments (OSEs) with the current NCEP's global data assimilation algorithms and existing satellite data have been conducted. The main goal of these experiments is to later evaluate the performance of the OSSE system, as the impact of GNSS RO in the OSSE system should be comparable to the impact of GNSS RO in the real world.

During this talk, the undergoing activities on RO OSSEs and some interesting results of the data denial experiments will be discussed.