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A new method is developed to detect cold pools from atmospheric soundings over tropical oceans and applied to sounding data from the Elucidating the Role of Cloud–Circulation Coupling in Climate (EUREC4A) field campaign, which took place south and east of Barbados in January–February 2020. The proposed method uses soundings to discriminate cold pools from their surroundings: cold pools are defined as regions where the mixed-layer height is smaller than 400 m. The method is first tested against 2D surface temperature and precipitation fields in a realistic high-resolution simulation over the western tropical Atlantic Ocean. Then, the method is applied to a dataset of 1068 atmospheric profiles from dropsondes (launched from two aircraft) and 1105 from radiosondes (launched from an array of four ships and the Barbados Cloud Observatory). We show that 7% of the EUREC4A soundings fell into cold pools. Cold-pool soundings coincide with (i) mesoscale cloud arcs and (ii) temperature drops of ∼1 K relative to the environment, along with moisture increases of ∼1 g kg−1. Furthermore, cold-pool moisture profiles exhibit a "moist layer" close to the surface, topped by a "dry layer" until the cloud base level, and followed by another moist layer in the cloud layer. In the presence of wind shear, the spreading of cold pools is favored downshear, suggesting downward momentum transport by unsaturated downdrafts. The results support the robustness of our detection method in diverse environmental conditions and its simplicity makes the method a promising tool for the characterization of cold pools, including their vertical structure. The applicability of the method to other regions and convective regimes is discussed. [ABSTRACT FROM AUTHOR]

The couplings among clouds, convection, and circulation in trade-wind regimes remain a fundamental puzzle that limits our ability to constrain future climate change. Radiative heating plays an important role in these couplings. Here we calculate the clear-sky radiative profiles from 2001 in-situ soundings (978 dropsondes and 1023 radiosondes) collected during the EUREC4A field campaign, which took place south and east of Barbados in January-February 2020. We describe the method used to calculate these radiative profiles and present preliminary results sampling variability at multiple scales, from the variability across all soundings to groupings by diurnal cycle and mesoscale organization state, as well as individual soundings associated with elevated moisture layers. This clear-sky radiative profiles data set can provide important missing detail to what can be learned from calculations based on passive remote sensing and help in investigating the role of radiation in dynamic and thermodynamic variability in trade-wind regimes. All data are archived and freely available for public access on AERIS (Albright et al. (2020), https://doi.org/10.25326/78). [ABSTRACT FROM AUTHOR]