Assessing trend and variation of Arctic sea-ice extent during 1979–2012 from a latitude perspective of ice edge
Assessing trend and variation of Arctic sea-ice extent during 1979–2012 from a latitude perspective of ice edge
复制标题
DOI：
10.3402/polar.v33.21249
复制
发表时间：
2014-01
期刊：
影响因子：
1.9
通讯作者：
W. Xia;H. Xie;C. Ke
中科院分区：
文献类型：
--
作者：
W. Xia;H. Xie;C. Ke
自20世纪70年代以来，北极海冰的范围（夏季）一直在缩小。然而，我们对这种收缩的详细空间变异性知之甚少。在这项研究中，我们检查（纬度）冰的范围沿着每个经度，使用每月北极冰指数数据集（1979-2012年）从国家冰雪数据中心。统计分析表明：（1）夏季除加拿大北极群岛、格陵兰岛和斯瓦尔巴特群岛外，大部分地区的海冰面积呈34年的下降趋势，退缩率为0.0562-0.0898纬度度/年（或6.26-10.00 km/年，显著性水平为0.05）;（2）对于在冬季月份中没有被大陆海岸线地理上静音的海冰，（1 - 4月）呈下降趋势，0.0216-0.0559纬度度/年（2.40- 6.22km/年，显著性水平为0.05）。从区域上看，8 ~ 10月楚科奇海海冰减少最明显，1 ~ 5月巴芬湾和格陵兰海海冰减少最明显，7 ~ 8月巴伦支海海冰减少最明显，8 ~ 9月拉普捷夫海和东西伯利亚海海冰减少最明显。趋势分析还表明：（1）自1999年以来，夏季冰面积的下降变得显著（在0.05的显著性水平上）;（2）冬季冰面积在2000年前后出现了明显的变化点（下降），在2005年前后变得具有统计学显著性。北极的太平洋-西伯利亚部分占夏季海冰减少的大部分，而大西洋部分的海冰冬季恢复趋于减少。
Arctic sea-ice extent (in summer) has been shrinking since the 1970s. However, we have little knowledge of the detailed spatial variability of this shrinking. In this study, we examine the (latitudinal) ice extent along each degree of longitude, using the monthly Arctic ice index data sets (1979–2012) from the National Snow and Ice Data Center. Statistical analysis suggests that: (1) for summer months (July–October), there was a 34-year declining trend in sea-ice extent at most regions, except for the Canadian Arctic Archipelago, Greenland and Svalbard, with retreat rates of 0.0562–0.0898 latitude degree/year (or 6.26–10.00 km/year, at a significance level of 0.05); (2) for sea ice not geographically muted by the continental coastline in winter months (January–April), there was a declining trend of 0.0216–0.0559 latitude degree/year (2.40–6.22 km/year, at a significance level of 0.05). Regionally, the most evident sea-ice decline occurred in the Chukchi Sea from August to October, Baffin Bay and Greenland Sea from January to May, Barents Sea in most months, Kara Sea from July to August and Laptev Sea and eastern Siberian Sea in August and September. Trend analysis also indicates that: (1) the decline in summer ice extent became significant (at a 0.05 significance level) since 1999 and (2) winter ice extent showed a clear changing point (decline) around 2000, becoming statistically significant around 2005. The Pacific–Siberian sector of the Arctic accounted for most of the summer sea-ice decline, while the winter recovery of sea ice in the Atlantic sector tended to decrease.