Given these factors, there is strong motivation for improved knowledge of its circum-Antarctic distribution, change and variability. By forming a recurrent, persistent, and highly consolidated substrate of sea ice and snow, fast ice strongly modulates important physical and biological processes occurring at the Antarctic coastal margin – including stabilisation of ice shelves that moderate ice sheet mass loss to the ocean and resultant sea level rise ( Massom et al., 2018). Depending on location, it can be either annual (forming each austral autumn–winter and melting back each spring–summer) or perennial ( Fraser et al., 2012), with multi-year fast ice attaining thicknesses up to several tens of metres (e.g. Landfast sea ice (fast ice) is a pre-eminent feature of the Antarctic near-coastal environment, where it forms a relatively narrow (several tens of kilometres to ∼ 200 km wide) zone of consolidated ice attached to grounded icebergs, coastal margins (including sheltered embayments), floating glacier tongues, and ice shelf fronts ( World Meteorological Organization, 1970). The new algorithm presented here will enable continuous large-scale fast-ice mapping and monitoring into the future. This new dataset ( Fraser et al., 2020) has wide applicability and is available at. This dataset was derived by compositing cloud-free satellite visible and thermal infrared imagery using an existing methodology, modified to enhance automation and reduce subjectivity in defining the fast-ice edge.
By alex p. 2000 series#
Here, we present the first continuous, high-spatio-temporal resolution (1 km, 15 d) time series of circum-Antarctic fast-ice extent this covers the period March 2000 to March 2018, with future updates planned. Antarctic fast-ice mapping to date has been limited to regional studies and a time series covering East Antarctica from 2000 to 2008. Given the wide-ranging importance of Antarctic fast ice and its sensitivity to climate change, improved knowledge of its change and variability in its distribution is a high priority.
Landfast sea ice (fast ice) is an important component of the Antarctic nearshore marine environment, where it strongly modulates ice sheet–ocean–atmosphere interactions and biological and biogeochemical processes, forms a key habitat, and affects logistical operations.