Lagrangian formation pathways of moist anomalies in the trade-wind region during the dry season: two case studies from EUREC4A ...

• Main Authors: Villiger, Leonie, Wernli, Heini, Boettcher, Maxi, Hagen, Martin, Aemisegger, Franziska
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2022
• Subjects: North Atlantic
• Online Access: https://dx.doi.org/10.3929/ethz-b-000583023; http://hdl.handle.net/20.500.11850/583023

Shallow clouds in the trade-wind region over the North Atlantic contribute substantially to the global radiative budget. In the vicinity of the Caribbean island of Barbados, they appear in different mesoscale organization patterns with distinct net cloud radiative effects (CREs). Cloud formation processes in this region are typically controlled by the prevailing large-scale subsidence. However, occasionally weather systems from remote origin cause significant disturbances. This study investigates the complex cloud–circulation interactions during the field campaign EUREC4A (Elucidate the Couplings Between Clouds, Convection and Circulation) from 16 January to 20 February 2020, using a combination of Eulerian and Lagrangian diagnostics. Based on observations and ERA5 reanalyses, we identify the relevant processes and characterize the formation pathways of two moist anomalies above the Barbados Cloud Observatory (BCO), one in the lower troposphere (∼ 1000–650 hPa) and one in the middle troposphere (∼ 650–300 ... : Weather and Climate Dynamics, 3 (1) ...