Tropical Cyclone Forecast Skill Impact Simulations with the NASA CYGNSS Constellation

The NASA Cyclone Global Navigation Satellite System (CYGNSS) is a confirmed spaceborne mission scheduled for launch in October 2016. The mission goals and objectives involve study of the surface wind structure in and near the inner core of tropical cyclones (TC). CYGNSS consists of a constellation of eight small observatories carried into orbit on a single launch vehicle. Each observatory carries a 4-channel bistatic radar receiver tuned to receive GPS navigation signals scattered from the ocean surface. The measured distortion to the navigation signals allows the ocean surface roughness statistics to be inferred, from which the near-surface wind speed is retrieved in a manner analogous to traditional ocean wind scatterometry. The eight satellites are spaced approximately twelve minutes apart in the same circular, low inclination orbit plane in order to provide frequent temporal sampling in the tropics. CYGNSS is expected to provide unprecedented temporal resolution and spatial coverage, under all precipitating conditions, and over the full dynamic range of wind speeds experienced in a TC. Mission simulations predict a median(mean) revisit time of 3(7) hours at all locations between 35o N and 35o S latitude..

The CYGNSS mission is currently in Phase D assembly, integration and test of the 8 Observatories and Deployment Module. In parallel with the hardware development, the mission's science team has developed a detailed mission simulator which has produced flight-like Level 1 and 2 science data products for the entire 2010 and 2011 Atlantic hurricane seasons, using HWRF as input winds, as well as flight-like science data products using Nature Run simulated input winds. These simulations have been used to conduct OSSE studies of the expected impact on tropical cyclone forecast skill due to the CYGNSS measurements.

A brief mission status will be reported at AMS 2016, followed by a summary of the OSSE studies that are currently underway.