Investigation of Changes in Extreme Temperature and Humidity Over China Through a Dynamical Downscaling Approach
Investigation of Changes in Extreme Temperature and Humidity Over China Through a Dynamical Downscaling Approach
复制标题
DOI：
10.1002/2017ef000678
复制
发表时间：
2017-11
期刊：
影响因子：
--
通讯作者：
Jinxin Zhu;Gordon H. Huang;Xiuquan Wang;G. Cheng
中科院分区：
文献类型：
--
作者：
Jinxin Zhu;Gordon H. Huang;Xiuquan Wang;G. Cheng
气候变化对公众健康的影响往往取决于多种气候变量。结合高温和相对湿度的健康相关指标最受关注。为了综合评价气候变化对中国的影响，本文研究了温度、相对湿度及其相互关系。通过PRECIS模型的组合温度和湿度的投影得到解决。通过对PRECIS模式的历史模拟结果的检验，初步验证了PRECIS模式在模拟中国历史气候方面的能力。根据良好的验证结果，在RCP下生成了合理的组合温度和相对湿度范围。结果表明，到世纪末，中国年平均气温将升高6°C。与温度的显著变化相反，相对湿度的最大变化幅度仅为基线期值的8%。在高辐射强迫情景下，预计本世纪末全国露点温度为14.9°C（在舒适区间内）。因此，高温和相对湿度对中国的综合影响远小于一般预期。尽管露点温度等影响相关指标并不像普遍预期的那样糟糕，但我们发现，在中国，极端高温的频率增加了40%，持续时间增加了150%。预计中国仍将比以往有更多的极端炎热天气，更频繁的高温极端事件，以及更长的温暖期。从区域上看，华南地区的平均、最高和最低气温变化最小，而所有五个高温指数的增幅最大。因此，未来两个时期华南地区的气候变化将比基准期更为剧烈。未来需要对华南地区给予额外的警告。
Impacts of climate change relating to public health are often determined by multiple climate variables. The health‐related metrics combining high‐temperature and relative humidity are most concerned. Temperatures, relative humidity and relationship among them are investigated here for a comprehensive assessment of climate change impacts over China. A projection of combined temperatures and humidity through the PRECIS model is addressed. The PRECIS model's skill in reproducing the historical climate over China was first gauged through validating its historical simulation with the observation data set in terms of the two contributing variables. With good results of validation, a plausible range of combined temperatures and relative humidity were generated under RCPs. The results suggested that the annual mean temperature of China will increase up to 6°C at the end of 21st century. Opposite to the significantly change in the temperature, the maximum magnitude of changes in relative humidity is only 8% from the value in the baseline period. The dew point temperature is projected to be 14.9°C (within the comfortable interval) over the whole nation under high radiative forcing scenario at the end of this century. Therefore, the combination effects of high temperatures and relative humidity are substantially smaller than generally anticipated for China. Even though the impact‐relevant metric like the dew point temperature is not projected as bad as the generally anticipated, we found that the frequency of high‐temperature extremes increases up to 40% and the duration increases up to 150% in China. China is still expected to have more number of extremely hot days, more frequent high‐temperature extremes, and longer duration of warm spell than before. Regionally, South China has the smallest changes in the mean, maximum and minimum temperatures while the largest increases in all five high‐temperature indices. Consequently, the climate over South China for two future periods will be changing more drastically than the baseline period. Extra cautions need to be given to South China in the future.