The Global Nature of Early‐Afternoon and Late‐Night Convection Through the Eyes of the A‐Train

• Published in: Journal of geophysical research. Atmospheres 2022-07, Vol.127 (13), p.n/a
• Main Authors: Pilewskie, J. A., L’Ecuyer, T. S.
• Format: Article
• Language: English
• Subjects: Anvil clouds; Atmospheric models; Carbon monoxide; Climate; Climate and weather; Climate models; Cloud structure; Clouds; Connecting; Convection; Convective clouds; Convective systems; Cooling; Cores; Earth; Energy budget; Energy output; Energy transfer; Geophysics; Global precipitation; Hydrologic cycle; Hydrological cycle; Mathematical models; Moisture effects; Night; Northern Hemisphere; Numerical models; Oceans; Rain; Rainfall; Rainfall amount; Sampling; Satellite constellations; Satellite observation; Satellites; Storm clouds; Storms; Sunlight; Thermal radiation; Time of use; Tropical climate; Updraft; Weather forecasting; Weather patterns
• ISSN: 2169-897X; 2169-8996
• DOI: 10.1029/2022JD036438

Characterizing macrophysical properties of deep convective systems on a global scale is a precursor to understanding their influence on Earth's Energy Budget and Water Cycle. This study documents the properties of global convective objects (COs) in the early afternoon (1:30 p.m. local time; LT) and overnight (1:30 a.m. LT) measurements from the A‐Train satellite constellation. CloudSat measurements are used to identify convective cores and establish their intensity, while other A‐Train data sets define cloud structure, storm spatial extent, rainfall yield, and radiative effects of each CO. Global distributions of storm characteristics are consistent with previous studies in which the most intense convection is located over tropical land, particularly over the Amazon and Congo Basin, while the largest COs occur over the Maritime Continent. Despite their limited twice‐daily sampling, A‐Train measurements capture that early afternoon convection over tropical land is both more intense and produces heavier rainfall than nighttime land‐based convection, while the day‐night differences are minimal over the tropical ocean. High‐resolution estimates of updraft cores reveal that CO size increases as the number of distinct cores in a CO increases owing to an increase in nonconvective rain and anvil cloud area. Convective objects generally cool the environment, which is strongest over the Northern Hemisphere midlatitudes, but cooling weakens as the nonconvective cloud fraction increases such that 30% of COs actually exert a net warming effect. These results suggest that A‐Train measurements may capture bulk connections between deep convective cloud features, precipitation, and radiative effects despite a lack of complete diurnal sampling. Plain Language Summary Storm clouds have a large impact on Earth's weather and climate. They produce a large fraction of global rainfall in short intense downpours and can both cool and warm the environment by reflecting sunlight and reducing emitted thermal radiation. Whether they cool or warm the atmosphere depends on cloud size and thickness as well as rainfall amount. These features impact the moisture and energy transfer within local and large‐scale environments, which influence weather patterns. Yet, it is difficult to represent the influences that storms have on a global scale in climate and weather forecasting models. This work provides a global perspective of early afternoon and late night storm signatures and their energy a