Quality assessment and improvement of the EUMETSAT Meteosat Surface Albedo Climate Data Record

Abstract

Abstract. Surface albedo has been identified as an important parameter for understanding and quantifying the Earth's radiation budget. EUMETSAT generated the Meteosat Surface Albedo (MSA) Climate Data Record (CDR) currently comprising up to 24 years of continuous surface albedo coverage for large areas of the Earth. This CDR has been created within the Sustained, Coordinated Processing of Environmental Satellite Data for Climate Monitoring (SCOPE-CM) framework. The long-term consistency of the MSA CDR is high and meets the Global Climate Observing System (GCOS) stability requirements for desert reference sites. The limitation in quality due to non-removed clouds by the embedded cloud screening procedure is the most relevant weakness in the retrieval process. A twofold strategy is applied to efficiently improve the cloud detection and removal. The first step consists of the application of a robust and reliable cloud mask, taking advantage of the information contained in the measurements of the infrared and visible bands. Due to the limited information available from old radiometers, some clouds can still remain undetected. A second step relies on a post-processing analysis of the albedo seasonal variation together with the usage of a background albedo map in order to detect and screen out such outliers. The usage of a reliable cloud mask has a double effect. It enhances the number of high-quality retrievals for tropical forest areas sensed under low view angles and removes the most frequently unrealistic retrievals on similar surfaces sensed under high view angles. As expected, the usage of a cloud mask has a negligible impact on desert areas where clear conditions dominate. The exploitation of the albedo seasonal variation for cloud removal has good potentialities but it needs to be carefully addressed. Nevertheless it is shown that the inclusion of cloud masking and removal strategy is a key point for the generation of the next MSA CDR release.

Validation practices for satellite‐based Earth observation data across communities

“…A multidecadal data product of surface albedo derived from geostationary satellite observations is available from EUMETSAT [Govaerts et al, 2008;Lattanzio et al, 2015]. Observations from geostationary satellites have enabled the retrieval of surface albedo since 1982 and therefore make it an important information source for climate studies.…”

“…Observations from geostationary satellites have enabled the retrieval of surface albedo since 1982 and therefore make it an important information source for climate studies. Details on the Meteosat surface albedo (MSA) retrieval scheme and data product validation are available in the literature [Loew and Govaerts, 2010;Lattanzio et al, 2013Lattanzio et al, , 2015. A unique feature of the MSA product is that it provides quantitative uncertainty information on a per pixel basis.…”

Land Surface Albedo Derived on a Ten Daily Basis from Meteosat Second Generation Observations: The NRT and Climate Data Record Collections from the EUMETSAT LSA SAF

“…They are further used to assess the risk management for envisaging mitigation procedures. In the context of climate variability it is important for the scientific community to understand if the trends associated with time series of geophysical variables are significant and also to assess their uncertainty [32]. This is possible only with the observation and analysis of long term CDRs.…”

Contribution of Land Surface Temperature (TCI) to Vegetation Health Index: A Comparative Study Using Clear Sky and All-Weather Climate Data Records

“…Climate Data Records (CDRs) [1] have been continuously and incrementally used in the last decade, and agencies such as the European Space Agency (ESA) or the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) provide datasets [2][3][4] for a diverse range of Essential Climate Variables (ECVs) that can be generated using satellite observations. These ECV CDRs cover parameters in various domains of the climate system, like the atmosphere (e.g., total column water vapor [5], Top-of-Atmosphere (TOA) radiance [6]), the ocean [7], and the land (e.g., albedo [8,9], Land Surface Temperature (LST) [10]). LST has recently been added as an ECV following the recognition of its role in processes within the interface between the soil and the atmosphere.…”