Moisture Transformation in Warm Air Intrusions Into the Arctic

Author(s)
C.F. Brunello, F. Gebhardt, A. Rinke, M. Dütsch, S. Bucci, H. Meyer, M. Mellat, M. Werner
Abstract

Warm Airmass Intrusions (WAIs) from the mid-latitudes significantly impact the Arctic water budget. Here, we combine water vapor isotope measurements from the MOSAiC expedition, with a Lagrangian-based process attribution diagnostic to track moisture transformation in the central Arctic Ocean during two WAIs, under contrasting sea-ice concentrations (SIC). During winter with high SIC, two moisture supplies are identified. The first is Arctic moisture, locally-sourced over the sea ice, with isotopic composition influenced by kinetic fractionation during ice-cloud formation and vapor deposition. This moisture is rapidly overprinted by low-latitude moisture advected poleward during WAI. In summer under low SIC, moisture is supplied through evaporation from land and ocean, with moisture removal via liquid-cloud and dew formation. The isotopic composition reflects the influence of higher relative humidity at the evaporation sites. Given the projected increase of frequency and duration of WAIs, our study contributes to assessing process changes in the Arctic water cycle.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
Journal
Geophysical Research Letters
Volume
51
ISSN
0094-8276
DOI
https://doi.org/10.1029/2024GL111013
Publication date
10-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105206 Meteorology, 105204 Climatology
Keywords
ASJC Scopus subject areas
Geophysics, General Earth and Planetary Sciences
Portal url
https://ucrisportal.univie.ac.at/en/publications/4d50df4d-fc85-4265-ac66-5a6f4b4e686a