Through an analysis of Landsat multispectral images of visible, thermal and near-infrared bands, the spatiotemporal change of biophysical parameters： NDVI （normalized difference vegetation index）, blackbody tempera...Through an analysis of Landsat multispectral images of visible, thermal and near-infrared bands, the spatiotemporal change of biophysical parameters： NDVI （normalized difference vegetation index）, blackbody temperature and albedo, were estimated for Mexicali city, using principal component analysis and time series. The satellite images correspond to the dates： April 6, 1993; May 3, 2000; May 12, 2003; May 17, 2008 and May 26, 2011; the results reveal a change in relation to urban growth. In 1993, the vegetation was 20% and in 2011 it decreased to 3.8%. The blackbody temperature increased from 34.0 ℃ to 41.0 ℃ and albedo decreased by 0.37 compared to 1993. The most deteriorated area appears in surroundings of the city because of the change in the vegetation cover by the urban elements.展开更多
文摘Through an analysis of Landsat multispectral images of visible, thermal and near-infrared bands, the spatiotemporal change of biophysical parameters： NDVI （normalized difference vegetation index）, blackbody temperature and albedo, were estimated for Mexicali city, using principal component analysis and time series. The satellite images correspond to the dates： April 6, 1993; May 3, 2000; May 12, 2003; May 17, 2008 and May 26, 2011; the results reveal a change in relation to urban growth. In 1993, the vegetation was 20% and in 2011 it decreased to 3.8%. The blackbody temperature increased from 34.0 ℃ to 41.0 ℃ and albedo decreased by 0.37 compared to 1993. The most deteriorated area appears in surroundings of the city because of the change in the vegetation cover by the urban elements.
