基于TDIC的上海市奉贤区大气能见度变化特征分析

利用2008～2017年上海市奉贤区气象监测数据以及2015～2017年空气质量监测数据,通过经验模态分解、Hilbert谱分析方法和时间内在关联分析方法(TDIC),重点探讨了相对湿度、浓度与大气能见度的相关关系。结果表明,奉贤区大气能见度具有明显的日变化和季节变化特征,能见度与相对湿度、和浓度变化呈现负相关性,在不同的相对湿度下,颗粒物浓度对大气能见度的影响不同。通过TDIC分析,在局部时间范围内,能见度与颗粒物浓度呈现正相关性,这种相关性变化会受到降水、风速、气压、温度等气象因素和极端天气的影响。通过上述分析,可以较好的探究大气能见度的变化特征。

Analysis of the Variability of Atmospheric Visibility in Fengxian District of Shanghai Based on TDIC

Based on the meteorological monitoring data from 2008 to 2017 and air quality monitoring data in Fengxian District of Shanghai from 2015 to 2017, the relationships among the relative humidity (RH), and concentrations and visibility were explored emphatically by empirical modal decomposition (EMD), Hilbert spectral analysis and time dependent intrinsic correlation (TDIC). The results showed that the atmospheric visibility has obvious diurnal and seasonal variation characteristics, and the visibility has negative correlation with the change of relative humidity, and concentration, and the influence of particle concentration on atmospheric visibility is different at different relative humidity. Based on TDIC methods, the visibility is positively correlated with particulate concentration within the local time frame. The correlation changes will be affected by rainfall, wind speed, atmospheric pollutant concentration changes, extreme weather conditions and other factors. Through the above analysis, a better understanding of the variability of atmospheric visibility can be achieved.