Generic strategy for consistency validation of the satellite-, in-situ-, and reanalysis—based climate data records (CDRs) essential climate variables (ECVs)

The Climate Data Record (CDR) is a time series of measurements of sufficient length, consistency and continuity to determine climate variability and change. The generation of ECVs (Essential Climate Variables)/CDRs needs to put strong emphasis on the generation of fully described, error-characterized and consistent satellite-based ECV products (Zeng et al. in Remote Sensing 11:1–28, 2019). For example, generation of many ECVs, such as in the ESA (European Space Agency) CCI (Climate Change Initiative) projects (Plummer et al. in Remote Sens Environ 203:2–8, 2017), requires ancillary information about the state of the atmosphere, e.g., cloud screening for SST (sea surface temperature) and atmospheric correction for space-borne altimeters. As such, the consistency between the various ECV products (e.g. cloud flagged in one ECV and non-flagged in another one) extends to ensuring consistency in the approaches of CDR generation. The in-situ datasets also need to be continuously characterized in terms of their long-term accuracy, stability and homogeneity. Reanalysis results, as an alternative source of ECV, requires similar endeavors to investigate its consistency (Zeng et al. in Int J Appl Earth Obs Geoinf 42:150–161, 2015).