Abstract Longwave downward radiation (LWDR) is another major energy source received by the earth's surface apart from solar radiation. Its importance in regulating air temperature and balancing surface energy is enlarged especially under cloudy-sky conditions. Unfortunately, to date, a large number of efforts have been made to derive LWDR from space under only clear-sky conditions leading to difficulty in utilizing space-based LWDR in most models due to its spatio-temporal discontinuity. Currently, only a few studies are focused on LWDR estimation under cloudy skies, while their global application is still questionable. In this paper, an alternative strategy is proposed aiming to derive high-resolution (1 km) cloudy-sky LWDR by fusing collocated satellite multi-sensor measurements. The results show that the newly developed method works well and can derive LWDR at a better accuracy with RMSE

中文翻译：

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通过整合 MODIS 和 AIRS/AMSU 测量进行多云天空地表长波向下辐射 (LWDR) 估计

摘要 长波下行辐射（LWDR）是地球表面除太阳辐射外的另一种主要能量来源。它在调节气温和平衡表面能方面的重要性尤其在多云天空条件下被放大。不幸的是，迄今为止，已经做出了大量努力来仅在晴天条件下从空间推导出 LWDR，导致由于其时空不连续性，在大多数模型中难以利用天基 LWDR。目前，只有少数研究集中在多云天空下的 LWDR 估计，而它们的全球应用仍然值得怀疑。在本文中，提出了一种替代策略，旨在通过融合并置卫星多传感器测量来获得高分辨率（1 公里）多云天空 LWDR。