Harmonised Night-light Data

The Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) stable nighttime light (NTL) data offer considerable potential for studying global and regional dynamics, including urban sprawl and electricity consumption. However, due to the lack of on-board calibration, it necessitates inter-annual calibration for practical applications. In this dataset, a stepwise calibration approach was employed to generate a temporally consistent NTL time series spanning from 1992 to 2013. Initially, temporal inconsistencies in the original NTL time series were identified. Subsequently, a stepwise calibration scheme was developed to systematically address over- and under-estimations in NTL images derived from specific satellites and years, utilizing temporally neighboring images as references for calibration. Following the stepwise calibration, the raw NTL series demonstrated improvement with a more consistent temporal trend. The global sum of NTL magnitude was maximally preserved in the data compared to the raw data, surpassing other conventional calibration approaches. The normalized difference index indicates that this approach can achieve a high level of agreement between two satellites in the same year.