Cloud top height (CTH) plays an important role in the Earth's radiation budget and thus in climate change. However, accurate CTH retrieval based on satellite data remains a challenge when using currently widespread methods based on passive remote sensing satellite data, particularly over the Arctic Ocean. It is well known that using geometric correlation between CTH and cloud-shadow distance along the normal direction of sunlight, cloud-edge top height (CETH) can be determined. However, this cloud-shadow method (CSM) exhibited larger CTH errors due to low-resolution weather satellite data of the past. The aim of the paper is to analyze the effect of higher-resolution images (MODIS with 250-m resolution) on CSM accuracy. We present a method in which CETH is first retrieved using the MODIS data, and to calculate CTH in the center of cloud region by combining the calculated CETH and cloud top brightness temperature using an environmental temperature lapse rate method. We validated 14 cases over the Arctic Ocean by the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) CTH lidar product and another two cases by radiosonde data. CSM revealed better performance (mean difference is 0.45 km and standard deviation is 0.92 km) compared to the operational MODIS CTH product (mean difference is −0.78 km and standard deviation is 1.78 km), when validated by the CALIPSO product. When validated by sounding data, CSM also performed better than the MODIS CTH product: the CSM CTH errors are 0.41 and 0.52 km in two sounding cases, while the corresponding MODIS CTH errors are −1.10 and 1.07 km. The CSM technique especially showed better performance for double-deck cloud systems. We conclude that further improvements in CTH accuracy based on CSM can be achieved by mainly using higher-resolution satellite imagery.

云顶高度（CTH）在地球的辐射预算中因而在气候变化中起着重要作用。然而，当使用基于被动遥感卫星数据的当前广泛使用的方法时，尤其是在北冰洋上，基于卫星数据的准确CTH检索仍然是一个挑战。众所周知，利用沿太阳的法线方向的CTH和云影距离之间的几何相关性，可以确定云沿的最高高度（CETH）。但是，由于过去的低分辨率气象卫星数据，这种云影法（CSM）表现出较大的CTH误差。本文的目的是分析高分辨率图像（分辨率为250-m的MODIS）对CSM精度的影响。我们提出了一种方法，其中首先使用MODIS数据检索CETH，并通过使用环境温度流失率方法将计算出的CETH与云顶亮度温度相结合，计算出云区域中心的CTH。我们通过CALIPSO（云气激光雷达和红外探路者卫星观测）CTH激光雷达产品验证了北冰洋地区的14例案例，并通过探空仪数据验证了另外2例案例。经CALIPSO产品验证，与运行的MODIS CTH产品（平均差异为-0.78 km和标准偏差为1.78 km）相比，CSM表现出更好的性能（平均差异为0.45 km，标准偏差为0.92 km）。通过测深数据验证后，CSM的性能也优于MODIS CTH产品：在两种测深情况下，CSM CTH误差分别为0.41和0.52 km，而相应的MODIS CTH误差为-1.10和1.07 km。对于双层云系统，CSM技术尤其显示出更好的性能。我们得出的结论是，主要通过使用更高分辨率的卫星图像，可以进一步提高基于CSM的CTH精度。