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ZhOU B.,Wuxi Meteorological Service of Jiangsu Province | Liu D.,Observatory of Jiangsu Province | Xia J.,Wuxi Meteorological Service of Jiangsu Province
Journal of Natural Disasters | Year: 2015

Using the meteorological data of Wuxi region from 2001 to 2012, this paper analyzes the characteristics of frost in Wuxi region and the relationship between minimum surface temperature and minimum air temperature, cloud amount, wind speed and air pressure. Results indicate that frost in Wuxi region mainly appears form Decerrir ber to the next March, general frost mainly appears from December to the next February, Serious frost mainly appears from December to the next January. In most cases, the minimum air temperatures are 0 - 3 °C higher than the minimum surface temperatures. This difference has a seasonal change, and the values are smaller in summer but larger in later Autumn, early Winter and Spring. Frost mainly appears when surface pressure is higher than 1025 hPa. When surface pressure is higher than 1030 hPa, there is more possibility of severe frost. Wind speed and cloud amount affects the difference between the minimum air temperatures and the the minimum surface temperatures, The higher the wind speed and the more cloud amound, the smaller the difference values. The chear and windless days are easier to form frost, when there is same minimum air temperature. According to forecast of minimum air temperature, wind speed and cloud amount, the look - up table method has a nice frost forecast effect.

Liu D.-Y.,Wuxi Meteorological Observatory of Jiangsu Province | Wei J.-S.,Observatory of Jiangsu Province | Yan W.-L.,Observatory of Jiangsu Province | Lu J.,Jiangsu Meteorological Information Center | Sun Y.,Observatory of Jiangsu Province
Huanjing Kexue/Environmental Science | Year: 2014

Based on the surface meteorological data of Jiangsu Province during 1980-2012, climatic characteristics and trends of the weather phenomenon of haze were analyzed. The result indicates that during 1980-2012, the haze day increased, and the severe and moderate haze days significantly increased. In the northern and coastal cities, haze days had a significant increase. Haze is often appeared in the fall and winter, and is rare in the summer, it also occurs inland, and is less in the coast. The haze happens more frequently in June since the straw burning during summer harvest time. The haze day was evenly distributed during the 80's, and increased during the 90's over southern and southwestern Jiangsu Province, middle and northern Jiangsu haze days had a growing after 2000, especially after 2010. The continuous, regional, and regional-continuous haze days were in an increasing trend. As the urban built-up area has been expanded each year, industrial emissions, coal consumption, and car ownership increase every year, resulting in regional temperature increase and relative humidity decrease, resulting in urban heat island and dry island effects. Thence the haze formation and maintenance conditions increased, which led to the increasing of haze days, and the continuous, regional and regional-continuous haze days were significantly increased.

Liu D.-Y.,Wuxi Meteorological Observatory of Jiangsu Province | Pu M.-J.,Observatory of Jiangsu Province | Yan W.-L.,Observatory of Jiangsu Province | Xie Z.-Z.,Huaian Meteorological Observatory of Jiangsu Province
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014

Based on the soundings of temperature, surface meteorological parameters, air pollutants concentration, the multi-day widespread fog-haze processes and the transformation between fog and haze during June 2012 at the downstream of the Huai River were investigated. Surface layer breeze provided nice dynamic conditions for the longtime maintain fog-haze; the neutrosphere or the inversion layer near the surface supplied a thermodynamic conditions; the large-scale crop residue burning provided enough condensation nucleus. During the haze-fog process, the visibility reduced with the wind speed decrease, and lifted with the wind speed increase. The formation and development of moderate and severe haze were accompanied with increasing specific humidity, while the haze-fog conversion processes were accompanied with decreasing specific humidity. The higher the specific humidity, the longer the fog-haze duration. The higher the specific humidity before the fog, the lower the minimum visibility during the fog. Visibility was positively correlated with the concentration of SO2 (Pearson correlation coefficients is 0.42), but was inversely correlated with PM2.5 and PM10 concentrations (Pearson correlation coefficients are -0.49 and -0.56, respectively). During the fog-haze processes, the upwind SO2, NO2 concentrations were higher than about 2times those of downwind. However, the downwind NO and PM10 concentrations were about 1.5 times higher than those of the upwind. Pollutants conversions occurred during the fog-haze processes.

Huaqing P.,Wuxi Meteorological Observatory of Jiangsu Province | Duanyang L.,Observatory of Jiangsu Province | Bin Z.,Wuxi Meteorological Observatory of Jiangsu Province | Yan S.,Wuxi Meteorological Observatory of Jiangsu Province | And 4 more authors.
Advances in Meteorology | Year: 2016

This paper analyzed the surface conditions and boundary-layer climate of regional haze events and heavy haze in southern Jiangsu Province in China. There are 5 types with the surface conditions which are equalized pressure (EQP), the advancing edge of a cold front (ACF), the base of high pressure (BOH), the backside of high pressure (BAH), the inverted trough of low pressure (INT), and saddle pressure (SAP) with the haze days. At that time, 4 types are divided with the regional haze events and each of which has a different boundary-layer structure. During heavy haze, the surface mainly experiences EQP, ACF, BOH, BAH, and INT which also have different boundary-layer structures. © 2016 Peng Huaqing et al.

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