PWV对全球气候变化的响应研究

PWV response to global climate change

利用全球导航卫星系统(global navigation satellite system,GNSS)反演得到全球118个IGS站点和251个探空站的大气可降水量(precipitable water vapor,PWV),结合温度、降水以及干旱指数资料,利用多种回归分析法(线性模型,断点模型和转折点模型)对全球PWV、温度、降雨和干旱的趋势和相关性问题进行研究。结果表明:①在全球大陆区域,PWV、温度和降雨上升速率分别为0. 215 mm/decade、0. 67℃/decade和0. 029 mm/decade;②PWV和标准化降水蒸散发指数(standardized precipitation evapotranspiration index,SPEI)之间没有直接相关性,但基于PWV获取的降雨转换率(rrecipitation conversion rate,PCR)与SPEI具有较强相关性,全球范围内近91%的地区相关系数大于0. 5,这为干旱监测提供了一种新方法。

Firstly,the retrieved precipitable water vapor from GNSS at 118 stations and 251 Radiosonde stations are used,combined with the data of surface temperature,precipitation and drought index,three regression analysis methods(linear model,breakpoints model and turning point model)and Pearson correlation method are used to analyze global PWV,temperature,precipitation and drought.The results show that:①In the global continental region,the rising rates of PWV,temperature and rainfall are 0.215 mm/decade,0.67 C/decade and 0.029 mm/decade,respectively.The turning points of PWV and temperature occur in 2012;②There is no direct correlation between PWV and SPEI,but the PRC based on PWV calculation has a higher correlation with SPEI,nearly 91%of the global regional correlation coefficient is greater than 0.5,PCR will be called a new method for drought monitoring.