Minute-Scale and Mesoscale Atmospheric Motion Vectors Retrieved From Fengyun-4B Geostationary Satellite High-Speed Imager Measurements

Atmospheric motion vectors (AMVs) from satellite measurements serve as critical indicators of atmospheric dynamics, playing an essential role in enhancing the prediction precision of numerical weather prediction (NWP) models through data assimilation (DA). The implementation of finer satellite-derived vector products has the potential to significantly augment the accuracy of atmospheric flow field data in high-resolution regional NWP model simulations, thereby fulfilling the burgeoning requirements of operational weather nowcasting and forecasting. This study is focused on the development of mesoscale AMV (MAMV) products, which are distinguished by their exceptional quality and spatiotemporal resolution, leveraging data from the geostationary high-speed imager aboard the Fengyun-4B geostationary meteorological satellite (FY-4B/GHI). MAMVs of FY-4B/GHI feature an enhanced horizontal resolution of 3 km, enabling more accurate identification and monitoring of nongeostrophic flow patterns of mesoscale weather systems, as well as their fast-evolving dynamical structures and characteristics. Furthermore, a comparative analysis with radiosonde measurements highlights the precision of MAMV products, as evidenced by a speed bias (SB) of 0.37 m/s, a speed root mean square error (sRMSE) of 4.68 m/s, and a direction root mean square error (dRMSE) of 26.35°. The prospects of high-resolution satellite wind field data hold great potential for propelling scientific advancement and enriching our comprehension of atmospheric dynamics. This is particularly valuable in the context of typhoon monitoring and forecasting, where such data can lead to significant improvements in predictive capabilities.