气象因素和前体物对中国东部O₃浓度分布的影响

Based on the methods of gravity center model, spatial autocorrelation analysis and geographical detector, this paper studied the spatial and temporal distribution of ozone concentration in Eastern China in 2016, revealed the impact of meteorological factors and precursors on the spatial distribution and evolution of ozone concentration. The results showed that: 1) Average monthly concentration of ozone went through three phases in Eastern China in 2016, rising gradually from January to March before reaching a fluctuating stage from April to September, it came to a decreasing phrase later from October to December. Ozone pollution was mainly witnessed at the second phase, which contributed 96 percent of the yearly ozone pollution. 2) Mainly affected by meteorological factors, namely lower precipitation, lower relative humidity and longer sunshine duration in the northern part of Eastern China, the annual ozone concentration of northern part was higher than that of southern part in Eastern China in general. Beside, pollution centers in core cities of urban agglomerations generated because of precursors, which was a significant factor of the yearly average ozone concentration distribution. 3) Spatial distribution of ozone concentration went through a higher-in-the-north pattern to the higher-in-the-south pattern in 2016. The monthly gravity center of ozone concentration was moving to the north from January to June, reaching its northernmost point in June. The higher-in-the-north pattern was at its most significant phase at that time, the highest point of pollution level was reached in Bohai Rim region. Then it moved backward to south until December when the southernmost point was reached, during which the distribution pattern was transforming into the higher-in-the-south pattern. During rainy season (from March to September), the spatial distribution of ozone concentration was mainly impacted by precipitation and relative humidity compared with a major impact by temperature in the rest of months. 4) Precursors worked with meteorological factors. A stronger photoreaction, as a result of rising temperature, positively magnified the impact of precursors while the decreasing temperature weakened photoreaction, which, as a result, may promote ozone consumption.