Airborne Closure of Moisture Budget inside Arctic Atmospheric Rivers

• DOI: 10.5194/egusphere-egu23-9784
• Publication Date: 2023-02-26T00:23:27Z
• Authors: Henning Dorff; Heike Konow; Vera Schemann; Davide Ori; Mario Mech; Felix Ament
• Keywords: Precipitable water; Dropsonde

Among arctic moist air intrusions, atmospheric rivers (ARs) provide substantial moisture transport over long distances poleward. Along their corridors, warm and masses undergo various transformation processes can cause regional sea ice decline, especially when they induce precipitation as rain. Quantifying the components of budget in ARs is key to elucidate efficiency. We close AR by measurements High Altitude LOng range research aircraft (HALO) during recent HALO-(AC)³ campaign (Spring, 2022) vicinity Fram Start Arctic ocean.Our analysis based on a strong event that HALO observed two consecutive days occurrence sequence intrusions mid March 2022. Dropsondes detect vertical profile therefrom quantify integrated water vapour (IVT) along cross sections. Applying regression methods then allows calculating divergence IVT. Since limited number dropsondes may deteriorate such calculations, we estimate arising uncertainties using ICOsahedral Nonhydrostatic model (ICON) storm-resolving configuration. Retrieved profiles from microwave radiometer (HAMP) further complement sporadic sonde-based profiles. use nadir cloud radar mounted aboard derive rates flight curtains.As comparison with ICON suggests, set IVT within reasonable range. The advection roughly twice mass convergence. Both act different heights, convergence dominating boundary layer (0-1 km) near low-level jet, whereas more elevated (1-4 km). strongest arises prefrontal sector while dominates slightly westwards centre. investigated caused rain sea-ice melting up 1.5 km. While there was less second observation day, mean increased first day. Model simulations show evaporation makes only small contribution budget.  Within simulations, purely along-track curtain against entire corridor indicates captures intensity corridor, but misrepresents its spatial variability. However, devices outperform terms variability conversion processes.