Compound drivers behind new record high temperatures and surface melt at the Antarctic Peninsula in February 2022

Abstract

The Antarctic Peninsula (AP) experienced a new extreme warm event and record high surface melt inFebruary 2022, rivaling the recent temperature records from 2015 and 2020, and contributing to analarming series of extreme warm events there. The northern/northwestern AP was directly impactedby an intense atmospheric river (AR) bringing anomalous heat and rainfall, while AR-enhanced foehneffect further warmed its northeastern side. The event was triggered by multiple large-scaleatmospheric circulation patterns linking the AR formation to tropical convection anomalies andstationary Rossby waves, with anomalous Amundsen Sea low and record-breaking blocking high. Thecascade of impacts culminated in widespread and intensive surface melt across the AP. The event wasstatistically attributed to global warming. Increasing frequency of such events can undermine thestability of the AP ice shelves, with multiple local to global impacts, including acceleration of the APice mass loss and changes in sensitive ecosystems.