Influence of the soil moisture effect on the thermal infrared emissivity
نویسنده
چکیده
The influence of soil moisture in thermal infrared emissivity is a known fact, but poorly studied in the past. An experiment for quantifying the dependence of emissivity on soil moisture has been designed. Six samples of superficial horizons of different Mediterranean soil types have been selected. Their emissivity has been measured at different soil water contents, using the twolid variant of the box method, whereas the gravimetric method has been selected for obtaining the soil moisture. As a result, the study shows that emissivity increases significantly when water content becomes higher, especially in sandy soils in the 8.2-9.2 μm range. A set of equations has been derived to obtain emissivity from soil moisture at different spectral bands for the analysed soil types.
منابع مشابه
Development of an Index-based Regression Model for Soil Moisture Estimation Using MODIS Imageries by Considering Soil Texture Effects
Soil moisture content (SMC) is one of the most significant variables in drought assessment and climate change. Near-real time and accurate monitoring of this quantity by means of remote sensing (RS) is a useful strategy at regional scales. So far, various methods for the SMC estimation using a RS data have been developed. The use of spectral information based on a small range of electromagnetic...
متن کاملRemoval of Topographical Effect from Remote Sensing Data for Thermal Inertia Modelling
Topographical effect was considered in the context of bare soil moisture assessment. Soil moisture was evaluated using thermal inertia modelling. As an input data in thermal inertia model, the images in visible and thermal infrared range are required. Two own programs were worked out modi for thermal inertia modelling and topo – for topographical effect removal. Standard GIS software can have a...
متن کاملInfluence of Thickness and Number of Silver Layers in the Electrical and Optical Properties of ZnO/Ag/ZnO/Ag/ZnO ultra-Thin Films Deposited on the Glass for Low-Emissivity Applications
We report on transparent ZnO/Ag/ZnO and ZnO/Ag/ZnO/Ag/ZnO thin-films were deposited on the glass substrate by RF and DC sputtering for ZnO and Ag targets, respectively. The electrical and optical properties of the single and double Low Emissivity coatings were investigated with respect to the deposition time of Ag mid layer. The visible transmittance remains about 65% for single and 45% for...
متن کاملDiscrimination of Senescent Vegetation Using Thermal Emissivity Contrast
A remote sensing method utilizing multiband thermal ble to determine in detail these characteristics directly, they are in turn estimated from land surface classifications infrared (8–12 lm) imagery that discriminates between obtained from a combination of ground observations and senescent vegetation and bare soil is described. This disremote sensing data. crimination is achieved by computing t...
متن کاملAn Improvement on Land Surface Temperature Determination by Producing Surface Emissivity Maps
Emissivity mapping of the Earth’s surface is the prerequisite to thermal remote sensing. A precise determinationof a surface's temperature is dependent upon the availability of precise emissivity data for that surface. The presentstudy area is a part of sugarcane plantation fields in the west part of Khuzestan province. In this work, TemperatureEmissivity Separation algorithm (TES) was applied ...
متن کامل