An exercise is carried out to analyse the variability in the Arctic snowmelt onset dates (SMOD) using 34 years of passive microwave radiometry data. For this study, the sea ice prevailing regions above 40° N have been clustered into thirteen sectors. Trend analysis of the SMOD shows that 10 sectors have negative trends meaning earlier melt onsets. Negative trends in the East Siberian Sea, Kara Sea, Laptev Sea, Chukchi Sea, Central Arctic Ocean, Canadian Archipelago, Beaufort Bay and Barents Sea are all statistically significant. Although the Greenland Sea shows a statistically significant positive trend is obtained. Inter-sectorial correlation shows strong positive correlations in many sectors such as between the Canadian Archipelago and the Central Arctic, Chukchi Sea—Central Arctic, East Siberian-Central Arctic. Moreover, correlation with the Arctic Oscillation (January to March average) shows negative correlations with the SMOD.

中文翻译：

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微波辐射测量对北极海冰融化开始的长期观测

使用 34 年的被动微波辐射测量数据进行了一项练习，以分析北极融雪开始日期 (SMOD) 的变化。在这项研究中，北纬 40°以上的海冰盛行区域被分为 13 个扇区。SMOD 的趋势分析显示，有 10 个行业出现负面趋势，意味着更早开始融化。东西伯利亚海、喀拉海、拉普捷夫海、楚科奇海、北冰洋中部、加拿大群岛、波弗特湾和巴伦支海的负趋势在统计上都很显着。虽然格陵兰海显示出统计上显着的积极趋势。部门间相关性在加拿大群岛与北极中部、楚科奇海—北极中部、东西伯利亚—北极中部等多个部门均呈现出较强的正相关关系。而且，