Abstract. This paper presents the third edition of the CM SAF cLoud, Albedo and surface RAdiation dataset from AVHRR data, CLARA-A3. The content of earlier CLARA editions, namely cloud, surface albedo, and surface radiation products, has been extended with two additional surface albedo products (blue and white sky albedo), three additional surface radiation products (net shortwave and longwave radiation, surface radiation budget) and two top of atmosphere radiation budget products (reflected solar flux and outgoing longwave radiation). The record length is extended to 42 years (1979–2020) by also incorporating results from the first version of the Advanced Very High Resolution Radiometer (AVHRR) imager (AVHRR/1). A continuous extension of the climate data record (CDR) has also been implemented by processing an interim climate data record (ICDR) based on the same set of algorithms but with slightly changed ancillary input data. All products are briefly described together with validation results and inter-comparisons with currently existing similar CDRs. The extension of the product portfolio and the temporal coverage of the data record, together with product improvements, is expected to enlarge the potential of using CLARA-A3 for climate change studies and, in particular, studies of potential feedback effects between clouds, surface albedo and radiation. The CLARA-A3 data record is hosted by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Satellite Application Facility on Climate Monitoring (CM SAF) and is freely available at https://doi.org/10.5676/EUM_SAF_CM/CLARA_AVHRR/V003.

中文翻译：

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CLARA-A3：第三版基于 AVHRR 的 CM SAF 云、辐射和地表反照率气候数据记录，涵盖 1979 年至 2023 年期间

摘要。本文介绍了来自 AVHRR 数据 CLARA-A3 的 CM SAF cLoud、反照率和地表辐射数据集的第三版。早期 CLARA 版本的内容，即云、表面反照率和表面辐射产品，已经扩展了两个额外的表面反照率产品（蓝天和白色天空反照率）、三个额外的表面辐射产品（净短波和长波辐射、表面辐射收支） ) 和大气辐射收支的两个顶层产品（反射太阳通量和出射长波辐射）。通过合并第一版高级甚高分辨率辐射计 (AVHRR) 成像仪 (AVHRR/1) 的结果，记录长度延长至 42 年（1979-2020）。气候数据记录 (CDR) 的持续扩展也已通过处理基于同一组算法但辅助输入数据略有变化的临时气候数据记录 (ICDR) 来实现。简要描述了所有产品以及验证结果和与当前存在的类似 CDR 的相互比较。产品组合的扩展和数据记录的时间覆盖范围，以及产品的改进，预计将扩大使用 CLARA-A3 进行气候变化研究的潜力，特别是云、地表反照率之间潜在反馈效应的研究和辐射。