Water isotopic characterisation of the cloud–circulation coupling in the North Atlantic trades – Part 1: A process-oriented evaluation of COSMO_iso simulations with EUREC^4A observations ...

• Main Authors: Villiger, Leonie, Dütsch, Marina, Bony, Sandrine, Lothon, Marie, Pfahl, Stephan, Wernli, Heini, Brilouet, Pierre-Etienne, Chazette, Patrick, Coutris, Pierre, Delanoë, Julien, Flamant, Cyrille, Schwarzenboeck, Alfons, Werner, Martin, Aemisegger, Franziska
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2023
• Subjects: North Atlantic
• Online Access: https://dx.doi.org/10.3929/ethz-b-000648569; http://hdl.handle.net/20.500.11850/648569

Naturally available, stable, and heavy water molecules such as HDO and H218O have a lower saturation vapour pressure than the most abundant light water molecule H216O; therefore, these heavy water molecules preferentially condense and rain out during cloud formation. Stable water isotope observations thus have the potential to provide information on cloud processes in the trade-wind region, in particular when combined with high-resolution model simulations. In order to evaluate this potential, nested COSMOiso (isotope-enabled Consortium for Small Scale Modelling; ) simulations with explicit convection and horizontal grid spacings of 10, 5, and 1ĝ€¯km were carried out in this study over the tropical Atlantic for the time period of the EUREC4A (Elucidating the role of clouds-circulation coupling in climate; ) field experiment. The comparison to airborne in situ and remote sensing observations shows that the three simulations are able to distinguish between different mesoscale cloud organisation patterns as ... : Atmospheric Chemistry and Physics, 23 (23) ...