Characterization of land surface thermal structure from NOAA-AVHRR data over a northern ecosystem

摘要: Abstract This paper focuses on the estimation and analysis of surface thermal parameters (emissivities temperatures) in a nordic environment (Quebec, Canada). The land cover this region varies from boreal forest south to tundra north. are estimated two variants new model that combines radiances short wave infrared (SWIR) spectral band [advanced very high resolution radiometer (AVHRR) channel 3: 3.55–3.93 μm] bands (AVHRR 4: 10.5–11.5 μm; AVHRR 5: 11.5–12.5 μm). study, carried out for images acquired different dates, reveals that, most situations, approaches allow separation emissivities temperatures. Analysis variations relation patterns shows they slightly variable 4, 5, with values generally greater than 0.95. Variations more important SWIR channel, where less 0.90 appear, especially urban areas. In general, increase density vegetation cover. Moreover, densely vegetated areas, reflectivities, which can be derived emissivities, appear well correlated reflectivities visible channel. As temperatures (LST) density, characterized by normalized difference index (NDVI), were considered. relations between (LST NDVI) show essentially opposite directions linear (positive negative correlations). light main results obtained, synergistic use regions (visible, near, mid-, infrareds) could useful parameterization ecosystems.