Nighttime Light Derived Assessment of Regional Inequality of Socioeconomic Development in China

Chenghu Zhou,Yuke Zhou,Ting Ma,Tao Xu

doi:10.3390/rs70201242

Abstract

Satellite-derived nighttime light (NTL) data have been extensively used as an efficient proxy measure for monitoring urbanization dynamics and socioeconomic activity. This is because remotely sensed NTL signals can be quantitatively connected to demographic and socioeconomic variables at regional and global scales. The recently composited cloud-free NTL imagery derived from the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite provides spatially detailed observations of human settlements. We quantitatively estimated socioeconomic development inequalities across 30 provinces and municipalities in mainland China using VIIRS NTL data associated with both regional gross domestic product (GDP) and population census data. We quantitatively investigated relations between NTL, GDP, and population using a linear regression model. Our results suggest that NTL radiances have significant positive correlations with GDP and population at different levels. Several inequality coefficients, commonly used in economics, were derived from VIIRS NTL data and statistical data at multiple spatial scales. Compared with the statistical data, NTL-derived inequality coefficients enabled us to elicit more detailed information on differences in regional development at multiple levels. Our study of provinces and municipalities revealed that county-level inequality was more significant than city-level inequality. The results of population-weighted NTL inequality indicate an obvious regional disparity with NTL distribution being more unequal in China’s undeveloped western regions compared with more developed eastern regions. Our findings suggest that given the timely and spatially explicit advantages of VIIRS, NTL data are capable of providing comprehensive information regarding inequality at multiple levels, which is not possible through the use of traditional statistical sources.

Highlights

Because of the current rapid economic growth in China, regional inequality is increasing and becoming a matter of contention that has received considerable attention from policy-makers and scholars [1]
We evaluated the relationships between nighttime light (NTL), gross domestic product (GDP), and population at the provincial and prefectural city levels by applying a linear regression model
The t-test of the two Gini index groups yielded a t-value of 5.7 and a p-value < 0.001, and the t-test of the Theil index yielded a t-value of 5.0 and a p-value < 0.001. These results indicate that the Gini and Theil indices derived at the county level differed significantly from those derived at the prefectural level, reflecting the multi-scale effect of inequality patterns in the statistical results

Summary

Introduction

Because of the current rapid economic growth in China, regional inequality is increasing and becoming a matter of contention that has received considerable attention from policy-makers and scholars [1]. The majority of studies on socioeconomic inequality in China have focused on several prominent economic indicators such as GDP, average income, and consumption expenditure in their analyses [5,6,7]. These studies applied several measurements to assess inequality such as the Coefficient of Variation (CV) and the Gini index. They have consistently observed an increase in regional inequality since 1992 ([7]). Inequality in relation to GDP appears to have increased more quickly during the post-reform period

Objectives

Results

Discussion

Conclusion