Comparative evaluation of VIIRS daily snow cover product with MODIS for snow detection in China based on ground observations
Comparative evaluation of VIIRS daily snow cover product with MODIS for snow detection in China based on ground observations
复制标题
基于地面观测的VIIRS日积雪产品与MODIS对中国积雪探测的对比评价
DOI：
10.1016/j.scitotenv.2020.138156
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发表时间：
2020
影响因子：
9.8
通讯作者：
Wang Shijin
中科院分区：
文献类型：
--
作者：
Zhang Hongbo;Zhang Fan;Che Tao;Wang Shijin
准确的积雪时空信息不仅对气候变化机制的研究具有重要意义，而且对山区水文模型的建立具有重要意义。索米-国家极轨合作伙伴S可见光红外成像辐射计套件(简称VNP)日积雪产品最近发布，有望在不久的将来取代中分辨率成像光谱仪(MODIS)积雪产品。作为广泛使用的MODIS产品的重要补充，也迫切需要对未来大比例尺日积雪覆盖图进行可靠的精度评估和比较。本研究首次利用330个台站的逐日积雪深度观测资料对中国地区逐日积雪资料的精度进行了评价。在青藏高原地区，平均CK(Cohen‘s Kappa)和FS(F-Score)分别高达0.72和0.75，而青藏高原地区的CK(Cohen’s Kappa)和FS(FS-Score)则明显下降到0.50和0.52。对于青藏高原以外的站点，VNP的精度略高于MODIS Terra，这是因为它具有较高的空间分辨率，但对于青藏高原内的站点，其精度低于Terra，这可能是因为它的地面观测与卫星飞越时间之间的时间间隔较长。相比之下，无论是在青藏高原外部还是在青藏高原内部，在中国卫星上，VNP都表现出比MODIS AQUA高得多的精度。该研究对中国地区日积雪产品的优化利用具有重要意义，可为气候分析和冰冻圈水文模拟提供更准确的积雪变化信息。
Accurate spatiotemporal information of snow cover not only is important for investigating the mechanisms of climate change but also greatly contributes to hydrological modelling in mountainous regions. The Suomi-National Polar-orbiting Partnership (S-NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) (referred to as VNP) daily snow cover product is recently released and expected to take place of Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover products in near future. As an important addition to the widely used MODIS products, there is also an urgent need for a reliable accuracy evaluation and comparison of VNP for future large-scale daily snow cover mapping. This study for the first time evaluates the accuracy of VNP daily snow cover data in China using daily snow depth observations from 330 stations. The accuracy of VNP data is generally good with the averaged CK (Cohen's Kappa) and FS (F-Score) as high as 0.72 and 0.75, respectively, but considerably decreases to 0.50 and 0.52 for the Tibetan Plateau. VNP shows slightly better accuracy than MODIS TERRA for stations outside the Tibetan Plateau owing to its higher spatial resolution, but its accuracy is lower than TERRA for those within the Tibetan Plateau possibly due to its longer time interval between ground observation and satellite overpass time. By contrast, VNP shows much better accuracy than MODIS AQUA in China including both outside and within the Tibetan Plateau. This study provides important implications for optimal use of VNP and MODIS daily snow cover products in China, which may further contribute to more accurate snow variation information for climate analysis and cryospheric hydrological modelling.