# The CYGNSS Mission: On-Going Science Team Investigations
## 2 Methodology, Results, and Discussions  
### Data Products  
CYGNSS is within the NASA's Earth System Science Pathfinder (ESSP) program. The original goal of CYGNSS was to further advance extreme weather predictions with a focus on TCs inner core process studies. CYGNSS was designed to resolve the lack of accuracy with current TCs intensity forecasts, which lie in inadequate measurements and modeling of the inner core. The inaccurate measurements result from two main aspects:  
Figure 1: Zoom-derived photo of some Science Team members attending the June 2020 CYGNSS meeting. * Traditional remote sensing techniques are blind to much of the inner core ocean surface when intense precipitation is in the eye wall and inner rain bands. * Traditional high-inclination orbit and wide-swath surface wind imagers do not provide an enough temporal sampling of the dynamically evolving (genesis and rapid intensification) phases of the TCs life cycle. CYGNSS was specifically designed to address these two limitations by combining the use of GNSS-R with the sampling properties of a constellation of eight microsatellites [15; 16; 17; 18; 19]. CYGNSS provides an unprecedented spatiotemporal resolution of the Earth's surface thanks to the multi-static nature of GNSS-R and the use of such a dense constellation of microsatellites. CYGNSS is the first operational GNSS-R mission launched into space, in 2016. Since CYGNSS's launch in December 2016, various science data products (Figure 2) have been created, such as an expansion of its wind speed measurements, ocean surface heat flux measurements, and land observations [20]. These scientific data products expand CYGNSS's core mission beyond TCs observations and bolster its reach and influence within the Earth science community. The results presented here focus on some of these products that have been developed and published since launch. All CYGNSS data products available to the public are distributed by the Physical Oceanography Distributed Active Archive Center (PODAAC). Session 1: CYGNSS Mission Overview and Data Products I  
The current v2.1 CYGNSS mission science data products assume that the GPS transmit power is constant. The Climate Data Record (CDR) v1.0 was released in May 2020 to improve product performance. This is the most stable, and most accurate product currently available. Current v3.0 products incorporate real time monitoring of GPS power. At present, all eight CYGNSS spacecrafts are healthy and operating nominally. There was the open call \"A.27 CYGNSS Competed Science Team\" within NASA Research Opportunities in Space and Earth Science (ROSES) 2020 with the following research topics: Atmospheric River Generation and Development, Wetland Methane Emissions, Dynamic Inland Water Mask Development, Process, Coupling and Feedback Studies, and Weather and Storm Surge Data Assimilation Studies. This ROSES seeks to support the continued use of both the ocean and land data products through scientific investigations and end-user applications. Several significant advances in ocean research activities were presented by the CYGNSS Science Team. By comparing the CYGNSS measured Mean-Square Slope (MSS) and modified Wave-Watch 3 (WW3) modeled MSS, it was shown that the mean MSS ratio has a dependence on both GPS Pseudo-Random Noise codes (PRNs) and CYGNSS Flight Models (FMs) (starboard and port antennas). A new end-to-end CYGNSS Level 1 calibration approach was proposed in [21] to: (1) improve the data quality of the CYGNSS Level 1 calibration and the Level 2 wind speed and MSS products; and (2) improve our understanding of the impacts of wind-wave and swell-wave on the GNSS-R ocean observations. The detailed performance assessments will be reported in the future. Sensitivity in CYGNSS data to wind direction was demonstrated by computing the kurtosis over areas in the glistening zone of different size and symmetry.