异常气候现象对我国雾霾影响程度和机制的研究

Abnormal climate, such as El Niño, perturbs normal weather states, which not only causes an abnormal performance in circulation, moisture, temperature and precipitation in an area, but also influences the degree and frequency of fog-haze weather in China. Aiming at understanding the relationship between the abnormal climate and the fog-haze weather, this project will: (1) analyze the contribution of abnormal climate to the fog-haze weather in the last 50 years, and its regional characteristics; (2) elucidate the scales and mechanisms of abnormal climate impacts on fog-haze and quantify its contributions through a climate/fog-haze weather modeling system; (3) establish the relationship between climate change indices, frequency of extreme weather events, and exceedances of regional haze pollution, based on the data-reanalysis, theoretical research, and numerical simulation study and (4) clarify the regional difference of the impacts in China through the regional difference in production, transformation, transports and depositions of haze pollutants, and find out the controlling climate factors in influencing the fog-haze weathers in various regions. The above research will strengthen the understanding of the mechanisms governing the fog-haze occurrences in China, and will mitigate the impacts of the abnormal climate on the fog-haze in the future, especially under the change scenarios of global climate.

厄尔尼诺等众多异常气候现象使正常的气候态势受到了扰动，不但造成了区域环流、水汽、温度和降水等的异常表现，也影响我国雾-霾天气的程度和频率。本项目针对影响我国雾-霾发生的关键气候因子：（1）剖析过去50年来异常气候对我国雾-霾天气的影响和联系以及区域特征；（2）通过再分析的气候数据驱动雾-霾天气模式，弄清异常气候因子对我国雾-霾影响的程度和机制，量化异常气候对我国雾-霾的贡献；（3）通过观测资料统计，数值模拟和相关理论分析，建立气候变化指数、异常天气事件和雾-霾污染频率之间的关系；（4）阐明异常气候对我国雾-霾影响的区域差异，包括雾-霾的产生，转换，传输及沉降区域特征，找出影响区域雾-霾的关键气候因子。通过上述研究，加深我们对雾-霾天气变化规律的认识。特别是在全球气候变化的框架下，从机制上把握异常气候变化对我国雾-霾的影响，为我国防灾减灾提供科学支撑。

随着温室气体浓度的不断上升，异常气候的发生频率也随之加大，对我国大气污染的影响作用也越来越显著，成为大气环境领域的热点问题之一。本研究利用长时间观测数据分析与数值模拟相结合的方式，系统建立了异常气候对我国雾霾污染影响机制分析的方法平台。首先整理了50年以来的气候及雾霾观测数据，分析了中国霾天气时空分布特征及成因的初探。在此基础上，利用多种数据的优势以及通过气候统计分析与数值模拟相结合的技术途径，对异常气候事件（包括ENSO、东亚季风、北极涛动、西太平洋暖池变暖等）对中国雾霾影响的结果进行了分析，包括华北地区、东北地区、四川盆地、长三角地区等等，并得出了对中国雾霾污染影响的系统结论。