摘要：This paper defined regional pollution day and regional heavy pollution day, calculated the atmospheric stability by Pasqual classification and the height of mixed layer by national standard method, established a conceptual model of meteorological conditions in Guanzhong Urban Agglomeration. The results show that：(1) The more possibility of the regional pollution and regional heavy pollution is, the lower the mixing layer height is. (2)The frequency of stability increased with degree of pollution, the frequency of regional heavy pollution stability reached nearly 60% as regional heavy pollution. (3)In heavily polluted area, the frequency of ground temperature inversion is nearly 90%, the average cumulative temperature inversion thickness is 260m at assurance rate of 80%, and the maximum temperature inversion strength is 10.8℃/100m. (4) Regional pollution is easy to occur when the frequency of quiet wind is higher than 50%. At the same time, it is easy to form wind convergence area in the hinterland of Guanzhong Area, which causes the accumulation of pollutants.
