Near-Storm Environments of Tropical Oceanic Convection As Observed from Recent NASA Airborne Campaigns

Airborne science missions have long provided unique measurements over tropical oceans that increased our understanding of 3-D convective structure and their environments. Satellite-based studies show regional variations in these relationships and structures, with future spaceborne missions aiming to provide improved global measurements of near-storm winds and moisture. Motivated by spaceborne instrument validation needs, NASA’s Convective Processes Experiment (CPEX) in 2017 carried a unique payload with a Doppler Wind Lidar (DAWN) and multi-frequency radar (APR-2), providing numerous cases for investigating environmental relationships with tropical oceanic convection in the Gulf of Mexico/Caribbean. As a follow-on, CPEX-Aerosols Wind (CPEX-AW) in 2021 provided additional cases in the tropical West Atlantic, while the 2022 CPEX-Cabo Verde (CPEX-CV) extended this airborne payload to the tropical East Atlantic. Using these datasets, we are investigating the environmental conditions favoring MCSs over the tropical Atlantic.

Our analysis of CPEX and CPEX-AW cases have suggested MCS formation favors higher moisture and deep vertical wind shear than more isolated convection. Comparisons between MCSs occurring in CPEX and CPEX-AW show different organizational structure that is linked to mid-level moisture and low-level wind shear. Our work is expanding to include the CPEX-CV cases; in particular, a research flight that sampled convection throughout various stages of its lifecycle associated with a weak African Easterly Wave. Despite deep convective cells producing lightning, there was a general lack of mesoscale organization on this well-sampled case. This presentation describes our initial insights into this case in the context of our conclusions from CPEX and CPEX-AW analyses.