The Winter Foehn Footprint Across McMurdo Dry Valleys of Antarctica Using a Satellite-Derived Data Set-AntAir v1.0

Datta R; Katurji M; Nielsen E; Meyer H; Zawar-Reza P; Valdes ML

Zusammenfassung

Abstract Continental-scale mosaics of satellite-based surface brightness temperature from thermal infrared band measurements and derived near-surface air temperatures from geostatistical modeling provide new opportunities for understanding wintertime Foehn wind warming and its potential impacts on the valley floor warming. We have detected and assessed Foehn signatures using a combined data analysis approach from previously developed and validated Antarctic-wide near-surface Air temperature data set (AntAir), automatic weather stations from the McMurdo Dry Valleys, and regional climate model simulations at 10 km spatial grid resolution. Self-organizing maps and data compositing methods on regional climate model outputs provided meteorological context for the AntAir-derived surface climate information. We conclude that AntAir is suitable for surface climatological analyses and improvements are underway to enhance the spatial resolution to sub-kilometer grid scales. Finally, by applying a Foehn detection algorithm over 13 years, we present the spatial climatological footprints of Foehn-induced warming across the Dry Valleys of Antarctica for the first time over the austral winters.