NASA’s Cyclone Global Navigation Satellite System (CYGNSS) Mission – Temporal Resolution of a Constellation Enabled by Micro-Satellite Technology

Hurricanes Katrina and Irene, each in their own way, are stark examples that while tropical storm track forecasts have improved in accuracy by ~50% since 1990, there has been essentially no improvement in the accuracy of the storm’s intensity prediction. In both cases, forecasters predicted almost exactly where the storms would make landfall, but failed to predict the storm\u27s intensity. Principle deficiencies of current tropical cyclone intensity forecasts lie primarily with inadequate observations and modeling of the inner core. The inadequacy in observations results from two causes: 1) Much of the inner core ocean surface is obscured from conventional remote sensing instruments by the storm\u27s intense precipitation. 2) The rapidly evolving (genesis and intensification) stages of the TC life cycle are poorly sampled in time by conventional polar-orbiting, wide-swath surface wind imagers. NASA’s Earth science mission, the Cyclone Global Navigation Satellite System (CYGNSS) is being designed to address tropical storm intensity forecast deficiencies by combining the all-weather performance of GNSS bi-static ocean surface scatterometry with the sampling properties of a satellite constellation. CYGNSS will demonstrate how micro-satellite technology can be applied to provide low cost solutions to fill capability voids in existing large-scale observatories. An overview will be presented of the CYGNSS mission, its science objectives, and how the use of a micro-satellite constellation results in sampling properties that are markedly improved beyond conventional wind speed observatories