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Atmospheric visibility trends in Xiqing and Tanggu meteorological stations in Tianjin from 2000 to 2010 are analyzed by using three different statistical methods (gradational analysis, Ridit analysis, and the frequency of “very good” visibility and “bad” visibility). The characteristics of lowvisibility weather and visibility effect factors are also analyzed. The results show that the atmospheric visibility exceeding 40 km did not appear in two meteorological stations during 11 years. The frequency of 2 to 9 km visibility increased at Xiqing Station year by year, while the frequency of 20 to 39 km visibility decreased from 2006 at Tanggu Station. The Ridit value decreased below 0.5 from 2006 at Xiqing Station. For Tanggu station, the Ridit value has a fluctuant and decreasing trend, and the least Ridit value appeared in 2006 (0.43). The frequency of “very good” visibility appears to have a decline trend at both stations, while the frequency of “bad” visibility appears to have an increase trend. Autumn and winter are highoccurrence seasons of lowvisibility weather, which is often accompanied by high relative humidity and low wind speed. The direction of the prevailing winds had differences at Xiqing and Tanggu stations. A negative correlation is found between relative humidity and atmospheric visibility, and wind speed and visibility has positive correlation. Visibility decreased in fluctuations, and on the contrary, total energy consumption increased year by year.