Tropical Cyclone Characterization via the DMSP Block 5D Satellite Sensor Suite

Abstract The Defense Meteorological Satellite Program (DMSP) Block 5D series of satellite sensors have been a cornerstone of the global effort to monitor tropical cyclone (TC) location, structure, and intensity since 1976. These satellite-based sensors uniquely complement land and ocean surface reports, radiosondes, aircraft, and geostationary visible (Vis) and infrared (IR) imagery. DMSP sensors have incorporated new technology with the ability to penetrate through clouds to see the critical TC structures needed to make accurate nowcasts and forecasts. The DMSP uses a combination of Vis/IR optical sensors and state-of-the-art passive microwave (PMW) imagers and sounders. Specific spectral bands are selected to observe desired phenomena (rain, temperature and moisture profiles, total precipitable water, cloud liquid water, etc.). These bands were first demonstrated by the National Aeronautics and Space Administration (NASA) satellites and then updated and expanded by DMSP operationally. The DMSP sounders were the first to exploit the water vapor sounding channels (183 GHz), now global weather constellation standards. These attributes have directly benefited the worldwide TC community by mitigating the inherent Vis/IR cloud limitations. Researchers have devised objective products that add forecaster value. These automated products provide near-real-time guidance supplementing human analyst’s outputs via the state-of-the-art TC structure and intensity characteristics. Follow-on civilian sensors continue these efforts and engineering strides now enable smaller and more cost-effective options that permit constellations that provide otherwise unattainable temporal sampling. This paper will focus on the DMSP Block 5D beginning in 1976 and continuing through satellites and sensors still operational today. Significance Statement Tropical cyclones (TCs) impact a large percentage of the global population due to our desire to live near the coastline and in tropical climates, but few people are aware of the satellite sensors used to monitor their at-sea birth and life cycle before landfall. This summary highlights the history of TC remote sensing and focuses on the Defense Meteorological Satellite Program (DMSP). The DMSP Block 5D visible (Vis) and infrared (IR) and especially the passive microwave imager and sounders have pioneered new sensor capabilities that have greatly advanced our ability to accurately monitor TCs in near–real time (NRT) globally as well as assist the research community. These sensor attributes have been incorporated into follow-on sensors that are operational today with wide-ranging benefits.