360-info/tracker-seaice: Daily sea ice extent: v2024-05-21

Tracks the daily sea ice extent for the Arctic Circle and Antarctica using the NSIDC's Sea Ice Index dataset, as well as pre-calculating several useful measures: historical inter-quartile range across the year, the previous lowest year and the previous year.本数据集依托美国国家冰雪数据中心（National Snow and Ice Data Center, NSIDC）的海冰指数（Sea Ice Index）数据集，追踪记录北极圈与南极洲的每日海冰范围；同时预先计算得到多项实用指标：全年历史四分位距、历史最低值年份以及上一年度的海冰相关数据。