Land

Albedo climatology 

Accurate and detailed knowledge about the radiative properties of Earth’s surface are crucial for many atmospheric remote sensing applications, such as aerosol, cloud and trace gas retrieval. To help meet this need, Empa created a set of monthly global black-sky albedo maps based on 11 spectral channels of MERIS, which is provided with a grid spacing of 0.25° x 0.25°. It is primarily used for trace gas and cloud retrievals in the Oxygen A-band (Popp et al., 2011 ) from sensors such as OMI, SCIAMACHY, and GOME. The data set is freely available on ESA’sTEMIS web site.

MERIS black-sky albedo
MERIS black-sky albedo for August (image by ESA/Empa)


Verifying sustainable forestry 

The Forest Stewardship Council (FSC) forest management certification is based on on-site evaluation in forest management units. These evaluations are usually performed once a year over a period of several days. However, especially in large-scale operations or in difficult terrain, this auditing method quickly tends to reach its limits and, consequently, the audit intensity and quality often suffer. A customized remote sensing service aiming at the provision of transparent, comprehensive and cost effective information has been designed and implemented by sarmap. It integrates products derived from spaceborne synthetic aperture radar and optical sensors within forestry models. It consists of two main components: thematic products (maps and change detection products) and estimates of key biophysical parameters, with the latter exclusively derived from synthetic aperture radar data.

Rice baseline map / Detailed planting date map
Left: Rice baseline map at 1 ha resolution for Thailand, Vietnam and Cambodia; product derived from ENVISAT ASAR wide swath data acquired from 2003-2001. Right: Detailed area and planting date map inferred from ASAR alternating polarization data. Such products are used as input to an agro-meteorological crop growth model for yield forecast ing (images by sarmap)


Rice crop assessment 

The importance of rice for food security in many Asian countries and a large part of the developing world is undisputed. In this context, sarmap in involved in the RIICE project, funded by the Swiss Agency for Development and Cooperation. Its goal is to set up information systems that help create rural advisory services and micro-insurance schemes, consequently reducing the vulnerability of rice production smallholders. Synthetic aperture radar data is used to determine the extent and area, biomass or damage extent of rice fields.

Rice baseline map / Detailed planting date map
Left: Rice baseline map at 1 ha resolution for Thailand, Vietnam and Cambodia; product derived from ENVISAT ASAR wide swath data acquired from 2003-2001. Right: Detailed area and planting date map inferred from ASAR alternating polarization data. Such products are used as input to an agro-meteorological crop growth model for yield forecast ing (images by sarmap)


Snow extent 

Snow extent maps for the European Alps are processed in near real time by the Remote Sensing Group at the University of Bern for every daytime overpass of the AVHRR sensors onboard NOAA and Metop. The snow retrieval depends on a robust threshold-based algorithm optimized for complex terrain. The detection thresholds vary according to landcover type and topographic features such as shadow. A detailed description of the snow retrieval method can be found in Huesler et al. (2012). Up-to-date snow maps as well as a sample of archived maps are available through the saturn portal.

Snow covered area in the European Alps
Snow covered area in the European Alps retrieved from Metop/AVHRR acquired at the receiving station of RSGB on November 24, 2011. Corresponding data is available from the saturn portal (image by RSGB/NOAA)