The Relationship Research Between SO₂ Spatial-temporal Changes And Underlying Surface Using Remotely Sensed Data In Zhejiang, China

Sulfur dioxide(SO2)is an important trace gas and one of the main atmospheric pollution components, and usually used as an indicator to monitor the environmental pollution. The development of theory in atmospheric remote sensing provides important theoretical support and technical means to study global climate change and atmospheric environment. Understanding the distribution of SO2 in China and its change has important significance on the atmospheric environmental research and air quality control. Being the developed district of China, Zhejiang Province is a typical region suffered from air pollutions as results of human activities. In this paper, OMI SO2 column density remotely sensed data processed by Matlab and Arcgis from 2005.1 to 2009.12 and the land use mapping using MODIS-EVI data, as well as to combine with SO2 ground measured data are get together, serve for analyzing the relationship between SO2 column densities and underlying surface of Zhejiang Province.The relationship between SO2 column density and vegetation coverage in 12 towns is also studied. The results indicated that the SO2 column densities in Zhejiang Province decreased from 2005 to 2009, and it showed distinct regional and seasonal variation characteristics. It has the highest concentration in winter while lowest in summer. The fitting accuracy of sinusoidal model reached to 0.65. It also presents zonal distribution and decreasing from northern to southern. Under the influence of the urbanization process, the highest SO2 column densities appeared at cities and metropolises which located in the Hangzhou-Jiaxing-Huzhou plain, northern area of Ningbo as well as the west and east of Zhejiang. Moreover the lowest column densities appeared at the forest areas which are in the south and west of Zhejiang. In addition, it has the higher SO2 column density over urban, cropland and water while lower values over forest. The result also showed that the higher SO2 column density appeared in towns which located in northern plain of Zhejiang province with lower vegetation coverage. SO2 concentration was negatively correlated with vegetation coverage.The results approved that the OMI SO2 column density remotely sensed data can be used in air quality monitoring at regional scale.