Mapping land surface emissivity in the Teide volcanic system

Resumen

In light the greatly improvement introduced by satellite remote sensing for Earth sciences ap-plications, increasing notably the quality of the surface parameters inferred, climate studies and models developed from them have experienced a significant progress. Even so, it is important to make sure the accuracy of the remote products by means of in situ observations. Although there are some natural surfaces in which a constant emissivity assumption could be assumed, as surfaces highly vegetated, in general, land surface emissivity (LSE) varies sig-nificantly with many factors, as physical constituents, surface moisture content, roughness or particle size. This lack of accurate surface emissivity information makes us to compile a spec-tral emissivity library in a suitable site in the Teide National Park, Tenerife Island (Spain), to be used in land surface temperature validation experiences, as well as to be incorporated in geological and climate studies. The zone is a highly-elevated volcanic site composed of different types of lava formed as a part of the volcanic activity of Tenerife Island. To this end, emissivity measurements of several volcanic rocks from the Teide National Park have been developed using the box method. They include both in situ and laboratory mea-surements. The results have been compared with LSE extracted by means of high spatial resolution information from the Advanced Spaceborne Thermal Emission and Reflectance Ra-diometer (ASTER) sensor and the Temperature and Emissivity Separation algorithm provided by the ASTER Standard Product AST-05.