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极地积雪和海冰厚度是气候变化的重要指标,也是船舶在冰区航行需要掌握的主要参数。2014和2015年在南极普里兹湾中山站附近布放了一种新式的温度链浮标,该浮标每天进行4次常规温度观测和1次加热升温观测,用于实时获取积雪和海冰剖面温度及厚度数据的研究。通过分析剖面温度曲线和升温曲线反映出的大气、积雪、海冰和海水4种介质的热传导特性差异,可利用人工识别的方法(人工经验法)获得大气/积雪、积雪/海冰和海冰/海水界面的位置。根据统计不同介质在升温响应和垂直温度梯度等方面的特性,找到合理阈值,可通过编写程序自动判断各界面的位置(自动程序法)。本文利用这两种方法来判断不同物质界面位置从而计算得到积雪和海冰厚度。与现场人工观测的海冰厚度相比,人工经验法的平均偏差和均方根偏差分别为2.1cm和6.4cm(2014年)以及4.3cm和6.5cm(2015年),自动程序法的平均偏差和均方根偏差分别为-6.8cm和6.4cm(2014年)以及4.5cm和6.6cm(2015年);对于积雪,人工经验法与现场人工观测的平均偏差和均方根偏差分别为0.5cm和8.5cm,而自动程序法的平均偏差和均方根偏差分别为4.7cm和10.8cm。自动程序法误差较人工经验法偏大,但考虑到整体冰厚和现场观测的误差,两种方法的结果均是可信的,精度是可以接受的。利用新式的温度链浮标实时获取南极普里兹湾积雪和海冰厚度是可行的。
Polar snow cover and thickness of sea ice are important indicators of climate change and are the main parameters that ships need to master in navigating ice fields. A new temperature chain buoy has been placed near Zhongshan Station in Prydz Bay, Antarctica in 2014 and 2015. The buoy carries out routine temperature and temperature heating observations of 4 times a day for acquiring snow and sea ice profiles in real time Research on Temperature and Thickness Data. By analyzing the difference of heat conduction characteristics between the four media of atmosphere, snow cover, sea ice and seawater reflected by the profile temperature curve and the temperature rising curve, the method of artificial identification (artificial experience method) can be used to obtain the atmosphere / snow cover, snow cover / sea ice And sea ice / sea water interface. According to the characteristics of different media in terms of temperature response and vertical temperature gradient, a reasonable threshold value can be found, and the position of each interface can be automatically determined by programming (automatic program method). This paper uses these two methods to determine the interface between different materials to calculate the thickness of snow and sea ice. The average deviation and root mean square deviation of the artificial experience method were 2.1cm and 6.4cm (2014) and 4.3cm and 6.5cm (2015), respectively, compared with the sea ice thickness manually observed in the field. The average deviation of the automatic program method And root mean square deviations of -6.8cm and 6.4cm (2014) and 4.5cm and 6.6cm (2015), respectively; mean deviations and root mean square deviations of artificial experience and field observations of snow cover were 0.5 cm and 8.5 cm, respectively, while the average deviation and root mean square deviation of the automatic program method were 4.7 cm and 10.8 cm, respectively. The error of the automatic program method is larger than that of the artificial experience method. However, the results of the two methods are credible considering the overall ice thickness and the errors observed in the field, and the accuracy is acceptable. It is feasible to obtain the snow and sea ice thickness in Prydz Bay, Antarctica in real time using the new temperature chain buoy.