MAPPING URBAN AREAS BY PERFORMING SYSTEMATIC CORRECTION FOR DMSP/OLS NIGHTTIME LIGHTS TIME SERIES IN CHINA FROM 1992 TO 2008

摘要

The stable lights data in the Version 4 Nighttime Lights Time Series Dataset gained by the Defense Meteorological Satellite Program's Operational Line-scan System can't be used to map urban areas directly because the data has no onboard calibration and many unstable lights are also included in the data. So the systematic correction was performed before the urban areas extraction according to the characteristic of stable lights data in China from 1992 to 2008 with the 1 km spatial resolution. It was found that, with systematic correction, the stable lights data could be strictly comparable from one year to the next, in which the remarkable differences of digital number values and the unstable lights were removed effectively. Besides, the urban areas extracted from the stable lights data could be used to describe the real process of urban expansion in China from 1992 to 2008.