Change and variability in East antarctic sea ice seasonality, 1979/80-2009/10

PLoS One. 2013 May 21;8(5):e64756. doi: 10.1371/journal.pone.0064756. Print 2013.

Abstract

Recent analyses have shown that significant changes have occurred in patterns of sea ice seasonality in West Antarctica since 1979, with wide-ranging climatic, biological and biogeochemical consequences. Here, we provide the first detailed report on long-term change and variability in annual timings of sea ice advance, retreat and resultant ice season duration in East Antarctica. These were calculated from satellite-derived ice concentration data for the period 1979/80 to 2009/10. The pattern of change in sea ice seasonality off East Antarctica comprises mixed signals on regional to local scales, with pockets of strongly positive and negative trends occurring in near juxtaposition in certain regions e.g., Prydz Bay. This pattern strongly reflects change and variability in different elements of the marine "icescape", including fast ice, polynyas and the marginal ice zone. A trend towards shorter sea-ice duration (of 1 to 3 days per annum) occurs in fairly isolated pockets in the outer pack from∼95-110°E, and in various near-coastal areas that include an area of particularly strong and persistent change near Australia's Davis Station and between the Amery and West Ice Shelves. These areas are largely associated with coastal polynyas that are important as sites of enhanced sea ice production/melt. Areas of positive trend in ice season duration are more extensive, and include an extensive zone from 160-170°E (i.e., the western Ross Sea sector) and the near-coastal zone between 40-100°E. The East Antarctic pattern is considerably more complex than the well-documented trends in West Antarctica e.g., in the Antarctic Peninsula-Bellingshausen Sea and western Ross Sea sectors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antarctic Regions
  • Ice Cover*
  • Seasons*
  • Surface Properties
  • Temperature

Grant support

The work was supported by the Australian Government's Cooperative Research Centre programme through the ACE CRC, and contributes to AAS Projects 3024 and 4116 and AAD CPC Project 18. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.