Pendugaan Hubungan Kondisi Topografi dengan Radiasi Spektral Citra Satelit TERRA MODIS L1B (Studi Kasus: Gunung Gede dan Gunung Salak)

Abstract

The objectives of this research are estimate the spectral radiation relationship with the topography on forest land cover and analyze the relationship of surface temperature between altitude on forest land cover in the area of Mount Salak and Mount Gede derived from MODIS TERRA L1B imagery at long wavelength channel (spectral radiation emission ). Surface temperature derived from TERRA MODIS L1B data, it use channel 31 and 32 with a wavelength of 10.780 to 11.280 and 11.770-12.270 . Spectral emission of radiation (longwave thermal) response topography indicated by the correlation coefficient of -0.5 to -0.9 while the spectral reflectance of radiation (short wave) did not respond to the topography shown by fluctuations in the value of the correlation coefficient with a range of -0.7 to 0.3. TERRA MODIS L1B image data indicated by the response to topography radiation emission spectral response of the altitude. Based on data derived from MODIS TERRA L1B image is obtained inversely proportional relationship between the temperature of the surface topography. Highest value of surface temperature and the lowest occurred in September and May. With the same land cover (forest), solar zenith angle affects the surface temperature value. In addition, there are many other factors that affect the surface temperature, some of which are atmospheric effects (emission and scattering), the latitude and air density. MODIS sensor can respond to topography due to the influence of the moist air density and specific heat of air varies with altitude and pressure.