6533b7dbfe1ef96bd1270932

RESEARCH PRODUCT

<title>Temperature and emissivity retrieval from DAIS data: application to the DAISEX campaigns in Colmar (France) and Barrax (Spain)</title>

subject

description

In the present paper it is presented a methodology to calculate the surface temperature (ST) from the combination of the radiometric temperature in two different DAIS (Digital Airborne Imaging Spectrometer) thermal bands using split-window (sw) method. To get this objective the MODTRAN 3.5 radiative transfer code was used to predict radiance for DAIS channels 74 (8.75 µm), 75 (9.65 µm), 76 (10.48 µm), 77 (1 1.27 µm), 78 (12.00 µm) and 79 (12.67 µm) at different aircraft altitudes with the appropriate channel filter functions. In order to analyse atmospheric effects a set of radiosoundings that cover the variability of surface temperature and water vapour concentration on a world-wide scale was used. Once the algorithm has been obtained, an application to DAIS images obtained in Colmar (France) and Barrax (Spain) during the DAISEX'98 and '99 ( Data Airborne Imaging Spectrometer Experiment ) campaigns framework has been made. Finally a comparison between the surface temperature obtained from DAIS data, previously corrected from the atmospheric and emissivity effect, and the simultaneous in-situ measurements, is included. The results show that the proposed theoretical sw are able to produce land surface temperature with a standard deviation lower than 1 K. This is in good agreement with the validation results obtained from DAISEX campaign.