Relationship of Convective Structure to Near-storm Environmental Moisture and Wind from the NASA CPEX-CV Field Campaign

Deep tropical oceanic convection (TOC) plays a key role in driving global weather and climate. Prediction challenges remain, however, partly attributed to a lack of understanding of tropical convective structure and evolution, including how TOC structure relates to near-storm environments. Therefore, collocated measurements of three-dimensional (3-D) convective structure—ranging from single-core cellular convection to multi-core convective systems —and near-storm environmental parameters are essential to improve convective process-level knowledge and, subsequently, weather and climate modeling. TOC structure and its associated near-storm environments have been researched in the western Pacific, eastern Pacific, and Indian basins and suggest the existence of regional variations in mean-layer moisture and vertical wind shear relationships with TOC structure. This regional variability necessitates further study of near-storm environmental relationships with TOC structure throughout all tropical oceanic regions, particularly the Atlantic basin which has not been well researched in this regard.

During September 2022, the NASA Convective Processes Experiment – Cabo Verde (CPEX-CV) airborne field campaign sampled 24 TOC systems over the east Atlantic, with particular focus on repeated sampling of convective regions and lifecycle stages. As such, CPEX-CV provided an exceptional opportunity to investigate near-storm moisture and wind relationships with 3-D TOC structure in this region. Starting with the collocated CPEX-CV airborne datasets from the triple-wavelength Airborne Precipitation Radar (APR-3), Doppler Aerosol WiNd Lidar (DAWN), and dropsondes, analysis over all CPEX-CV convective cases reveals large near-storm environmental variance both amongst convective systems of similar organizational structure and within individual convective systems themselves. Notable distinctions emerge amongst the variability, however, with multi-core TOC associated with generally lesser CAPE than single-core TOC and greater low-level wind convergence correlated with greater precipitation intensity in the east Atlantic. Furthermore, near-storm, mean-layer moisture and deep-layer vertical wind shear are generally greater for multi-core TOC compared to single-core TOC. This presentation will highlight these CPEX-CV results in the context of other tropical oceanic regions, providing an ongoing interregional assessment of 3-D TOC structure relationships with near-storm environments.