Change and variability in Antarctic coastal exposure, 1979-2020

• Published in: Nature Communications
• Main Authors: Reid, PA, Massom, RA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2022
• Subjects: Environmental Sciences; Other environmental sciences; Other environmental sciences not elsewhere classified; Antarctic; Ross Sea; Indian; Antarc*; Ice Shelf; Sea ice
• Online Access: https://doi.org/10.1038/s41467-022-28676-z; http://www.ncbi.nlm.nih.gov/pubmed/35246526; http://ecite.utas.edu.au/154018

Increased exposure of Antarcticas coastal environment to open ocean and waves due to loss of a protective sea-ice buffer has important ramifications for ice-shelf stability, coastal erosion, important ice-ocean-atmosphere interactions and shallow benthic ecosystems. Here, we introduce a climate and environmental metric based on the ongoing long-term satellite sea-ice concentration record, namely Coastal Exposure Length. This is a daily measure of change and variability in the length and incidence of Antarctic coastline lacking any protective sea-ice buffer offshore. For 19792020, ~50% of Antarcticas ~17,850-km coastline had no sea ice offshore each summer, with minimal exposure in winter. Regional summer/maximum contributions vary from 45% (Amundsen-Bellingshausen seas) to 58% (Indian Ocean and Ross Sea), with circumpolar annual exposure ranging from 38% (2019) to 63% (1993). The annual maximum length of Antarctic coastal exposure decreased by ~30 km (~0.32%) per year for 19792020, composed of distinct regional and seasonal contributions.