Thawing of soils in Siberia observed by the ERS-1 scatterometer between 1992 and 1995
Thawing of soils in Siberia observed by the ERS-1 scatterometer between 1992 and 1995
复制标题
1992年至1995年间ERS-1散射仪观测到的西伯利亚土壤融化情况
DOI：
10.1109/igarss.1996.516956
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
V. Wismann
中科院分区：
文献类型：
--
作者：
K. Boehnke;V. Wismann
根据ERS-1散射仪在不同入射角获得的西伯利亚上空多时间雷达后向散射测量数据，开发了一种监测土壤上层状态（冻结/解冻）的方法。在春季和秋季在一定程度上，归一化雷达截面（NRCS）数据显示出明显的变化，这可以归因于解冻和冻结土壤。在春季，在雪融化，NRCS第一次下降了5分贝，不久后，当土壤开始解冻，急剧增加。在秋天，土壤的冻结是一个渐进的过程。由于西伯利亚试验场面积巨大，整个地区解冻需要三个多月的时间。1992年至1995年，地图的解冻时间段的西伯利亚试验场，揭示了地理分布和年际变化的“解冻开始”。月SSM/I积雪数据和现场气温数据的第一次比较证实了所提出的技术的良好行为。
Based on multi-temporal radar backscatter measurements over Siberia, obtained from the ERS-1 scatterometer at various incidence angles, a method was developed for monitoring the state (frozen/thawed) of the upper layer of the soils. In spring and to some lesser extent in fall, the normalized radar cross section (NRCS) data show distinct variations which can be attributed to thawing and freezing soils. In spring, during snow melt, the NRCS first decreases by up to 5 dB and shortly later, when the soils start thawing, increases dramatically. In autumn, the freezing of the soils is a more gradual process. Due to the huge extent of the Siberian test site, it takes more than three months for the entire region to be thawed. For the years 1992 to 1995, maps of the time period of thawing were constructed for the Siberian test site which reveal the geographical distribution and the interannual variability of the "onset of thawing". A first comparison with monthly SSM/I snow cover data and in situ air temperature data confirms the good behavior of the proposed technique.