Ongoing Conflict Makes Yemen Dark: From the Perspective of Nighttime Light

Huichan Liu,Guojin He,Wei Jiang,Tengfei Long

doi:10.3390/rs9080798

Abstract

The Yemen conflict has caused a severe humanitarian crisis. This study aims to evaluate the Yemen crisis by making use of time series nighttime light images from the Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite sensor (NPP-VIIRS). We develop a process flow to correct NPP-VIIRS nighttime light from April 2012 to March 2017 by employing the Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) stable nighttime light image. The time series analyses at national scales show that there is a sharp decline in the study period from February 2015 to June 2015 and that the total nighttime light (TNL) of Yemen decreased by 71.60% in response to the decline period. The nighttime light in all provinces also showed the same decline period, which indicates that the Saudi-led airstrikes caused widespread and severe humanitarian crisis in Yemen. Spatial pattern analysis shows that the areas of declining nighttime light are mainly concentrated in Sana’a, Dhamar, Ibb, Ta’izz, ’Adan, Shabwah and Hadramawt. According to the validation with high-resolution images, the decline in nighttime light in Western cities is caused by the damage of urban infrastructure, including airports and construction; moreover, the reason for the decline in nighttime light in eastern cities is the decrease in oil exploration. Using nighttime light remote sensing imagery, our findings suggest that war made Yemen dark and provide support for international humanitarian assistance organizations.

Highlights

The Yemen crisis has lasted more than six years since it began in 2011, and it has caused severe political instability and humanitarian crisis
total nighttime light (TNL) can be used to demonstrate the level of nighttime light for countries and provincial regions, and it relates to human activity [27]
The TNL of Yemen from April 2012 to March 2017 was calculated for each month (Figure 8)

Summary

Introduction

The Yemen crisis has lasted more than six years since it began in 2011, and it has caused severe political instability and humanitarian crisis. According to the report on Yemen released by the humanitarian response organization on 26 February 2016 [1], 21.2 million people were in need of humanitarian assistance, accounting for 81.85% of the total population of Yemen. In 2015, the Yemen humanitarian overview published by the humanitarian information unit [2] showed that over 10 million people were in need of food, water and healthcare. 124 incidents in Yemen between 1 and 31 January 2015 and found a total number 5239 deaths and injuries, and this number was higher than those for Syria (4205), Iraq (3327) and Nigeria (1640). Civilians have accounted for 86% of the total number of deaths and injuries in Yemen [3].

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Conclusion