Remote sensing of human beings-a perspective from nighttime light

City lights,fishing boats,and oil fields are the major sources of nighttime lights,therefore the nighttime light images provide a unique source to map human beings and their activities from outer space.While most of the scholars focused on application of nighttime light remote sensing in urbanization and regional development,the actual fields are much wider.This paper summarized the applications of nighttime light remote sensing into fields such as the estimation of socioeconomic parameters,monitoring urbanization,evaluation of important events,analyzing light pollution,fishery,etc.For estimation of socioeconomic parameters,the most promising progress is that Gross Domestic Product and its growth rate have been estimated with statistical data and nighttime light data using econometric models.For monitoring urbanization,urban area and its dynamics can be extracted using different classification methods,and spatial analysis has been employed to map urban agglomeration.As sharp changes of nighttime light are associated with important socioeconomic events,the images have been used to evaluate humanitarian disasters,especially in the current Syrian and Iraqi wars.Light pollution is another hotspot of nighttime light application,as the night light is related to some diseases and abnormal behavior of animals,and the nighttime light images can provide light pollution information on large scales so that it is much easier to analyze the effects of light pollutions.In each field,we listed typical cases of the applications.At last,future studies of nighttime light remote sensing have been predicted.