Improvement of the spatial resolution of MODIS coastal waters thermal mapping

Thermal mapping is an highly relevant tool for the assessment of the quality of coastal waters. Remote sensing is an useful technique for monitoring large surfaces in near real time, nevertheless, spatial resolution represents an important limiting factor. In this work it the spatial improvement, from 1km to 250m, of MODIS thermal imagery on coastal water obtained with the SWTI (SharpeningWater Thermal Imagery) is shown. This algorithm is applied, for the first time, to MODIS images acquired on the lagoon of Venice and on the delta of the Po River. The performances of SWTI are evaluated taking as a reference a couple of ASTER images acquired simultaneously to the MODIS images and on the same areas. Moreover, the water temperatures obtained with a simple bilinear interpolation of the MODIS images is also considered. Several statistical parameters, as bias and root mean square difference, are used to quantify the the difference between ASTER and MODIS/SWTI water temperatures along coastlines. In all the the cases these differences are lower than 1K.