The 2010 heatwave in eastern Europe and Russia ranks among the hottest events ever recorded in the region^1,2. The excessive summer warmth was related to an anomalously widespread and intense quasi-stationary anticyclonic circulation anomaly over western Russia, reinforced by depletion of spring soil moisture^1,3,4,5. At present, high soil moisture levels and strong surface evaporation generally tend to cap maximum summer temperatures^6,7,8, but these constraints may weaken under future warming^9,10. Here, we use a data assimilation technique in which future climate model simulations are nudged to realistically represent the persistence and strength of the 2010 blocked atmospheric flow. In the future, synoptically driven extreme warming under favourable large-scale atmospheric conditions will no longer be suppressed by abundant soil moisture, leading to a disproportional intensification of future heatwaves. This implies that future mid-latitude heatwaves analogous to the 2010 event will become even more extreme than previously thought, with temperature extremes increasing by 8.4 °C over western Russia. Thus, the socioeconomic impacts of future heatwaves will probably be amplified beyond current estimates.

东欧和俄罗斯在2010年的热浪之中，是该地区有史以来最热的事件^1,2。夏季过多的温暖与俄罗斯西部异常广泛分布和强烈的准平稳反气旋环流异常有关，春季土壤水分的枯竭强化了这种异常^1,3,4,5。目前，高土壤湿度和强烈的地表蒸发往往倾向于限制夏季最高温度^6,7,8，但这些限制可能会在未来变暖的情况下减弱^9,10。在这里，我们使用一种数据同化技术，其中微调了未来的气候模型模拟，以真实地表示2010年受阻大气流的持久性和强度。将来，在有利的大规模大气条件下，由天气驱动的极端变暖将不再被大量的土壤水分所抑制，从而导致未来热浪不成比例地加剧。这意味着与2010年事件类似的未来中纬度热浪将变得比以前想象的更加极端，俄罗斯西部的极端温度升高了8.4°C。因此，未来热浪的社会经济影响可能会超出目前的估计。