Seismic Indirect Economic Loss Assessment and Recovery Evaluation Using Night-time Light Images n Application for Wenchuan Earthquake

Abstract. Seismic indirect economic loss not only has a major impact on regional economic recovery policies, but also related to the economic assistance at the national level. Due to the Cross-regional economic activities and the difficulty of obtaining data, it's difficult that the indirect economic loss survey covers all economic activities. However, night-time light in an area can reflect the economic activity of the region. This paper focuses on the indirect economic losses caused by the Wenchuan earthquake in 2008 and evaluated the progress of restoration and reconstruction based on night-time light Images. First, the functional relationship between GDP and night-time light parameters was established based on the pre-earthquake data. Next, the indirect loss of the earthquake was evaluated by the night-time light attenuation in the disaster area after the earthquake. Then, the capacity recovery, which is characterized by the brightness recovery process of the light area, was evaluated. Lastly, the process of light expansion in the disaster area was analyzed to evaluate the economic expansion speed and efficiency.