NUCAPS OLR Product Performance Evaluation and Environmental Application Through Synergistic Use of VIIRS True Color Maps

The National Oceanic and Atmospheric Administration (NOAA) Unique Combined Atmospheric Processing System (NUCAPS) is the hyperspectral sounding retrieval system that produces near-real-time top-of-the-atmosphere (TOA) Outgoing Longwave Radiation (OLR). OLR is the energy emitted from the Earth in the form of thermal radiation and observed by the Cross Track Infrared Sounders (CrIS) on the Joint Polar Satellite System (JPSS) satellites and Infrared Atmospheric Sounding Interferometer (IASI) on the Metop satellites. The NOAA-21 (previously known as JPSS-2) satellite was launched in November 2022, and its product performance evaluation is underway.
Before the Atlantic hurricane season began, NOAA predicted 12-17 named storms this year, and by the end of June, three tropical cyclones were named by the National Hurricane Center. Tropical wave Cindy developed in the Main Development Region off the coast of Africa on June 18, 2023, and evolved into a tropical storm on June 23, before dissipating three days later. A storm’s deep convection increases local longwave cooling and decreases TOA OLR, allowing OLR to be a proxy for tropical cyclogenesis.
This presentation evaluates daily AM/PM and monthly NOAA-21 CrIS OLR against the NOAA-20 CrIS, NOAA-20 CERES, and Aqua AIRS OLR products, demonstrating minimal spatial differences and a close statistical agreement. Furthermore, it looks at the OLR diurnal variability of tropical storm Cindy’s best track and discusses the environmental application of coupling the OLR with VIIRS True Color Maps.