ASPeCt bridge-based sea-ice observations – Ross Sea, Autumn 2025

The Antarctic Sea ice Processes and Climate [ASPeCt] data sets submitted here have been collected systematically from the bridge of the Xue Long II, CHINARE icebreaker, while it transited through pack ice during the JTRES voyage in the autumn of 2025.Quantifiable observations of sea-ice thickness and related characteristics of the sea ice, snow, ocean and surface atmosphere were recorded hourly while the vessel moved through the sea-ice zone. When the vessel was stopped or had not moved at least 6nm since the previous observation, no observations were made. The observation protocol was endorsed by the Scientific Commission for Antarctic Research (under their ASPeCt EG programme) as the preferred method for conducting ship-based observations of sea-ice characteristics. Details can be found in Worby and Allison [1999].The relevant spreadsheets (csv file) contains the following information: Header name; Physical parameter; UnitYear; Year    Date; Day/Month/Year    Julian Day; Day of year    Time (UT); Time of day in Universal time: Hours/Minutes/Seconds    Lat (degrees N); Latitude; degrees NLon(degrees E); Longitude; degrees EConc; Total ice concentration; TenthOW; Open-water classification; See Worby and Allison [1999]c1; Ice concentration of primary ice category; Tenthty1; Ice type of primary ice category; See Worby and Allison [1999]iz1; Thickness of primary ice category; cmf1; Floe size of primary ice category; See Worby and Allison [1999]t1; Topography of primary ice category; See Worby and Allison [1999]s1; Snow type on primary ice category; See Worby and Allison [1999]sz1; Snow thickness on primary ice category; cmc2; Ice concentration of secondary ice category; Tenthty2; Ice type of secondary ice category; See Worby and Allison [1999]iz2; Thickness of secondary ice category; cmf2; Floe size of secondary ice category; See Worby and Allison [1999]t2; Topography of secondary ice category; See Worby and Allison [1999]s2; Snow type on secondary ice category; See Worby and Allison [1999]sz2; Snow thickness on secondary ice category; cmc3; Ice concentration of tertiary ice category; Tenthty3; Ice type of tertiary ice category; See Worby and Allison [1999]iz3; Thickness of tertiary ice category; cmf3; Floe size of tertiary ice category; See Worby and Allison [1999]t3; Topography of tertiary ice category; See Worby and Allison [1999]s3; Snow type on tertiary ice category; See Worby and Allison [1999]sz3; Snow thickness on tertiary ice category; cmSea; Sea-surface temperature; degrees CAir; Surface-air temperature; degrees CReference: Worby, A.P., and I. Allison, A Technique for Making Ship-Based Observations of Antarctic Sea Ice Thickness and Characteristics, PART I Observational Technique and Results, Antarctic CRC Report No. 14, ISBN: 1 875796 09 6, 1999.

本次提交的南极海冰过程与气候（Antarctic Sea ice Processes and Climate，缩写ASPeCt）数据集，由中国极地考察破冰船“雪龙二号”（Xue Long II）在2025年秋季JTRES航次穿越浮冰区期间，从驾驶台系统性采集所得。
船舶在海冰区域航行期间，每小时记录海冰厚度及海冰、积雪、海洋与近地表大气的相关可量化观测数据；若船舶停航或自上次观测后移动距离不足6海里，则不开展观测。
该观测规程已获南极研究科学委员会（Scientific Commission for Antarctic Research，缩写SCAR）旗下ASPeCt专家组（ASPeCt EG programme）认可，作为船舶观测海冰特征的标准方法，详细信息可参考Worby与Allison[1999]的研究。
相关电子表格（CSV格式文件）包含以下字段，各字段对应关系为：表头名称；物理参数；单位：
Year；年份；无单位
Date；日期（日/月/年）；无单位
Julian Day；年积日；无单位
Time (UT)；世界时时间（时/分/秒）；无单位
Lat (degrees N)；纬度；北纬度数（°）
Lon(degrees E)；经度；东经度数（°）
Conc；总海冰密集度；十分制
OW；开阔水分类；详见Worby与Allison[1999]
c1；第一类冰密集度；十分制
ty1；第一类冰型；详见Worby与Allison[1999]
iz1；第一类冰厚度；厘米（cm）
f1；第一类冰浮冰大小；详见Worby与Allison[1999]
t1；第一类冰地形；详见Worby与Allison[1999]
s1；第一类冰表面积雪类型；详见Worby与Allison[1999]
sz1；第一类冰表面积雪厚度；厘米（cm）
c2；第二类冰密集度；十分制
ty2；第二类冰型；详见Worby与Allison[1999]
iz2；第二类冰厚度；厘米（cm）
f2；第二类冰浮冰大小；详见Worby与Allison[1999]
t2；第二类冰地形；详见Worby与Allison[1999]
s2；第二类冰表面积雪类型；详见Worby与Allison[1999]
sz2；第二类冰表面积雪厚度；厘米（cm）
c3；第三类冰密集度；十分制
ty3；第三类冰型；详见Worby与Allison[1999]
iz3；第三类冰厚度；厘米（cm）
f3；第三类冰浮冰大小；详见Worby与Allison[1999]
t3；第三类冰地形；详见Worby与Allison[1999]
s3；第三类冰表面积雪类型；详见Worby与Allison[1999]
sz3；第三类冰表面积雪厚度；厘米（cm）
Sea；海表温度；摄氏度（℃）
Air；近地表气温；摄氏度（℃）
参考文献：Worby, A.P. 与I. Allison, 《南极海冰厚度及特征船舶观测技术（第一部分：观测技术与结果）》，南极合作研究中心报告第14号，ISBN: 1 875796 09 6，1999年。