俄罗斯科学院Vladimir Semenov等报道了20世纪上半叶北极海冰的变化。相关论文于2024年6月22日发表在《大气科学进展》杂志上。

据介绍，近几十年来，北极海冰面积(SIA)的缩小是持续气候变化的一个显著表现。自1979年以来，卫星连续观测北极海冰的变化，自20世纪50年代以来监测相对较好，但由于缺乏观测，早期的变化很大。最近，基于综合区域海冰观测或应用混合模型—经验方法提出了几种历史网格海冰密集度(SIC)的重建方法。

研究基于已确定的SIC与地表气温、海面温度和海平面压力模式之间的共变，对1901-2019年期间的SIC进行了重建。研究人员将重建的3月和9月海冰数据与常用的HadISST1.1和SIBT1850数据集进行了比较。重建显示，在20世纪初北极变暖事件发生的同时，在1920年至1940年期间，SIA大幅减少。这种负的SIA异常在HadISST1.1数据中是不存在的。SIA异常幅度在3月份达到约为80万平方公里，在9月达到约为150万平方公里。

该异常比SIBT1850数据集中的异常强三倍。9月份SIA下降幅度较大，主要是由于70°-80°纬向的北冰洋西段SIC减少的幅度较大。研究结果强调，该重建提供了网格化的月度数据，这些数据可以作为研究20世纪上半叶的北极气候的大气再分析和模型实验的边界条件。

附：英文原文

Title: Arctic sea ice variations in the first half of the 20th century: a new reconstruction based on hydrometeorological data

Author: Vladimir Semenov, Tatiana Aldonina, Fei Li, Noel Keenlyside, Lin Wang

Issue&Volume: 2024-06-22

Abstract: The shrinking Arctic sea ice area (SIA) in recent decades is a striking manifestation of the ongoing climate change. Variations of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea ice concentration (SIC) data were recently presented based on synthesized regional sea ice observations or by applying a hybrid model-empirical approach. Here, we present a SIC reconstruction for 1901-2019 period based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea ice data for March and September are compared to frequently used HadISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in HadISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln.km² in March and 1.5 mln.km² in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western Sector of the Arctic Ocean in the 70°-80°N latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century.

DOI: 10.1007/s00376-024-3320-x

Source: http://www.iapjournals.ac.cn/aas/en/article/doi/10.1007/s00376-024-3320-xviewType=HTML