论文标题
极端温暖的夏天和欧洲热浪的罕见事件算法研究
Rare event algorithm study of extreme warm summers and heat waves over Europe
论文作者
论文摘要
由于缺乏统计成本的计算成本足以采样罕见事件，因此缺乏统计成本，因此对气候模型中极端的分析受到了阻碍。我们证明了罕见事件算法如何改善最新气候模型中极端事件的统计数据。我们在当今的气候下研究法国和斯堪的纳维亚半岛上极端温暖的夏天和热浪。该算法将模拟集中在重要性事件上，并改变了区域温度的概率分布，使温暖的夏天变得普遍。我们估计了极端的返回时间，比直接采样可行的数量级要大，并且我们计算了有条件的统计学意义复合图，该量在极端的情况下有条件。我们表明，极端温暖的夏天与波数3半球远程连接模式有关，最极端的夏天与罕见的亚季节中热浪的连续性有关。
The analysis of extremes in climate models is hindered by the lack of statistics due to the computational costs required to run simulations long enough to sample rare events. We demonstrate how rare event algorithms can improve the statistics of extreme events in state-of-the-art climate models. We study extreme warm summers and heatwaves over France and Scandinavia with CESM1.2.2 in present-day climate. The algorithm concentrates the simulations on events of importance, and shifts the probability distributions of regional temperatures such that warm summers become common. We estimate return times of extremes orders of magnitude larger than what feasible with direct sampling, and we compute statistically significant composite maps of dynamical quantities conditional on the occurence of the extremes. We show that extreme warm summers are associated to wavenumber 3 hemispheric teleconnection patterns, and that the most extreme summers are related to the succession of rare subseasonal heatwaves.
