Abstract

The relationship between the solar activity and Antarctic sea ice extent (SIE) has been intensified during recent years (2005-2019) and the observed sharp decrease in Antarctic SIE since 2014 may be partly attributed to the decline of recent solar cycle. Diagnosis analysis reveals that enhanced solar radiation could induce a negative Antarctic Oscillation (AAO) response by modulating the coupling between the stratosphere and troposphere. The AAO tends to play a bridge role in the linkage between the solar activity and Antarctic SIE. The associated intensity and latitudinal-shift of circumpolar westerlies could produce the changes of the sea ice coverage.

Introduction

The broad region around the South Pole is occupied by the Antarctic ice sheet, which is an important component of the global climate system (Simmonds, 2015). The Antarctic sea ice has a distinct annual cycle, covering an area larger than the Antarctic continent during the austral winter with a coverage maximum in September, while it reaches the minimum value in February (Parkinson and Cavalieri, 2012; Holland, 2014). Based on the reliable satellite multichannel passive-microwave record since late-1970s, it has been shown that the Antarctic sea ice extent (SIE) has experienced a gradual increase (by about 1.5% per decade) through early-2010s, although it may mask some larger opposing regional trends (Rignot et al., 2013; Simpkins et al., 2013; Turner et al., 2015). The Antarctic SIE reached the single-day maximum on 20th September 2014 of 20.14×106 km2. Followed by a rapid decrease, the SIE reached a new recorded troughing yearly-average value of 10.7×106 km2 in 2017 during the satellite era (Parkinson, 2019; Liu et al., 2020). The loss of sea ice over Antarctic from 2014 to 2017 is much more than that over Arctic for the past three decades and thus attracts attention of many scientists (Turner and Overland, 2009; Meehl et al., 2016; Turner et al., 2017; Yang et al., 2020).

This content is only available via PDF.
You can access this article if you purchase or spend a download.