He Bin, Huang Ling, Wang Qianfeng
1] College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China [2] Joint Center for Global Change Studies, Beijing 100875, China.
1] College of Environment and Resources, Fuzhou University, Fuzhou 350108, China [2] Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China.
Sci Rep. 2015 Jul 8;5:12004. doi: 10.1038/srep12004.
The relationship between precipitation deficits and extreme hot temperatures has been documented in observation and modeling studies. However, it is unclear whether and how increases in maximum temperatures will impact diurnal temperature range (DTR) extremes. Here, we used observational data sets from meteorological stations in China to examine the trends in high DTR extremes from 1971 to 2013, represented by the percentage of high DTR days (%HDD) and maximum high DTR duration (MHDD), as well as their relationships with precipitation deficits over the past four decades in China. We identified both positive and negative trends in the %HDD and MHDD in China during each season, implying an inhomogeneous behavior of DTR and DTR extremes. Furthermore, we observed a significant negative relationship between precipitation deficits and the %HDD and MHDD during each season, and the relationship was strongest in the summer. The statistical analysis of this coupled behavior indicated that precipitation deficits were related to an increase in high DTR extremes, with a 22% average higher probability of the occurrence of DTR extremes after dry conditions than wet conditions in the summer. Knowledge from this study has important implications for interpreting climate anomalies.
降水不足与极端高温之间的关系已在观测和模型研究中得到记录。然而，最高气温的升高是否以及如何影响日较差（DTR）极端值尚不清楚。在此，我们利用中国气象站的观测数据集，研究了1971年至2013年期间以高DTR日百分比（%HDD）和最大高DTR持续时间（MHDD）表示的高DTR极端值的趋势，以及它们与中国过去四十年降水不足的关系。我们发现中国每个季节的%HDD和MHDD均存在正负趋势，这意味着DTR和DTR极端值表现出不均匀性。此外，我们观察到每个季节降水不足与%HDD和MHDD之间存在显著的负相关关系，且这种关系在夏季最为强烈。对这种耦合行为的统计分析表明，降水不足与高DTR极端值的增加有关，夏季干旱条件下DTR极端值出现的平均概率比湿润条件下高22%。这项研究所得出的知识对于解释气候异常具有重要意义。
