Swathi M, Kumar Avinash, Mohan Rahul
National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Goa, India.
National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Goa, India.
Mar Pollut Bull. 2023 Mar;188:114634. doi: 10.1016/j.marpolbul.2023.114634. Epub 2023 Jan 30.
Sea ice variability patterns are highly influenced by several large-scale ocean-atmospheric oscillations. We analysed both statistical and wavelet coherence methods to examine sea ice's interannual and interdecadal variability. During the past 42-year, the total Southern Ocean sea ice extent (SIE) has expanded, while the Amundsen-Bellingshausen Sea SIE has decreased. A wavelet coherence analysis (WCA) of El Niño Southern Oscillation (ENSO) and the SIE in various sectors revealed an out-of-phase correlation between the Indian Ocean and the Ross Sea. There are significant out-of-phase correlations between sea ice variability and Indian Ocean Dipole (IOD) on an interannual scale. A consistent phase relationship was seen between SIE and Southern Annular Mode (SAM) over the past decade, with in-phase relationships advancing to out-of-phase relationships. The Interdecadal Pacific Oscillation (IPO) shifted from positive to negative after the 1990s. In recent years, SAM has had a stronger impact on sea ice variability than ENSO.
海冰变化模式受到几种大规模海洋 - 大气振荡的高度影响。我们分析了统计方法和小波相干方法,以研究海冰的年际和年代际变化。在过去的42年里,南大洋海冰总面积(SIE)有所扩大,而阿蒙森 - 别林斯高晋海的海冰总面积则有所下降。对厄尔尼诺 - 南方涛动(ENSO)和各区域海冰总面积进行的小波相干分析(WCA)显示,印度洋和罗斯海之间存在反相关关系。在年际尺度上,海冰变化与印度洋偶极子(IOD)之间存在显著的反相关关系。在过去十年中,海冰总面积与南半球环状模(SAM)之间呈现出一致的相位关系,从同相关系转变为反相关系。20世纪90年代后,年代际太平洋振荡(IPO)从正位相转变为负位相。近年来,SAM对海冰变化的影响比ENSO更强。