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Fold Geometry and Terminology #Structural #Geomorphology #Geography

Fold Geometry and Terminology #Structural #Geomorphology
#Geography

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Thermal Infrared Remote Sensing

1. Principles Thermal Infrared Remote Sensing is based on the detection of naturally emitted electromagnetic radiation from objects, rather than reflected solar energy. According to Planck's Radiation Law , all objects with a temperature above absolute zero (0 K) emit electromagnetic radiation. For Earth surface features, the peak emission lies in the Thermal Infrared (TIR) region of 3–14 μm of the electromagnetic spectrum. The amount of radiation emitted is primarily a function of surface temperature and emissivity . Sensors measure the radiant energy flux density (W/m²) , which is later converted to surface temperature using Stefan-Boltzmann's Law . 2. Radiation Properties in TIR Emissivity (ε): Ratio of radiation emitted by a surface to that emitted by a perfect blackbody at the same temperature. Natural surfaces like water (ε ≈ 0.98) have high emissivity, while bare soils and metals have lower values. Blackbody: An idealized object th...

Regional Geography, Systematic Geography, Idiographic, Nomothetic, Inductive and Deductive Approaches

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Atmospheric Window

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Radar image. Polarization in Remote Sensing

L band radars operate on a wavelength of 15-30 cm and a frequency of 1-2 GHz. L band radars are mostly used for clear air turbulence studies. S band radars operate on a wavelength of 8-15 cm and a frequency of 2-4 GHz. Because of the wavelength and frequency, S band radars are not easily attenuated. . Polarization refers to the direction of travel of an electromagnetic wave vector's tip: vertical (up and down), horizontal (left to right), or  circular (rotating in a constant plane left or right). . a synthetic aperture radar (SAR) for high-resolution imaging. a radar altimeter, to measure the ocean topography. echo amplitude a wind scatterometer to measure wind speed and direction. Other types of radars have been flown for Earth observation missions: precipitation radars such as the  Tropical Rainfall Measuring Mission, or cloud radars like the one used on Cloudsat. . RISAT-1 (SAR, ISRO India, 2012) RORSAT (SAR, Soviet Union, 1967-1988) Seasat (SAR, altimeter, scatterometer, US, 19...

Discrete Detectors and Scanning mirrors Across the track scanner Whisk broom scanner.

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