CLARA-A1: a cloud, albedo, and radiation dataset from 28 yr of global AVHRR data 1Swedish Meteorological and Hydrological Institute (SMHI), Norrköping, Sweden
28 May 2013
2Finnish Meteorological Institute (FMI), Helsinki, Finland
3Deutscher Wetterdienst (DWD), Offenbach, Germany
4Royal Netherlands Meteorological Institute (KNMI), De Bilt, the Netherlands
*now at: HKV Consultants, Lelystad, the Netherlands
Received: 12 November 2012 – Published in Atmos. Chem. Phys. Discuss.: 09 January 2013 Abstract. A new satellite-derived climate dataset – denoted CLARA-A1 ("The CM SAF cLoud, Albedo and RAdiation
dataset from AVHRR data") – is described. The dataset covers the 28 yr
period from 1982 until 2009 and consists of cloud, surface albedo, and
radiation budget products derived from the AVHRR (Advanced Very High
Resolution Radiometer) sensor carried by polar-orbiting operational
meteorological satellites. Its content, anticipated accuracies, limitations,
and potential applications are described. The dataset is produced by the
EUMETSAT Climate Monitoring Satellite Application Facility (CM SAF) project.
Revised: 26 April 2013 – Accepted: 02 May 2013 – Published: 28 May 2013
The dataset has its strengths in the long duration, its foundation upon a
homogenized AVHRR radiance data record, and in some unique features, e.g.
the availability of 28 yr of summer surface albedo and cloudiness
parameters over the polar regions. Quality characteristics are also well
investigated and particularly useful results can be found over the tropics,
mid to high latitudes and over nearly all oceanic areas.
Being the first CM SAF dataset of its kind, an intensive evaluation of the
quality of the datasets was performed and major findings with regard to merits and
shortcomings of the datasets are reported. However, the CM SAF's long-term
commitment to perform two additional reprocessing events within the time
frame 2013–2018 will allow proper handling of limitations as well as
upgrading the dataset with new features (e.g. uncertainty estimates) and
extension of the temporal coverage.
Citation: Karlsson, K.-G., Riihelä, A., Müller, R., Meirink, J. F., Sedlar, J., Stengel, M., Lockhoff, M., Trentmann, J., Kaspar, F., Hollmann, R., and Wolters, E.: CLARA-A1: a cloud, albedo, and radiation dataset from 28 yr of global AVHRR data, Atmos. Chem. Phys., 13, 5351-5367, doi:10.5194/acp-13-5351-2013, 2013.