As European heatwaves become more severe, summers in the United Kingdom (UK) are also getting warmer. The UK record temperature of 38.7 °C set in Cambridge in July 2019 prompts the question of whether exceeding 40 °C is now within reach. Here, we show how human influence is increasing the likelihood of exceeding 30, 35 and 40 °C locally. We utilise observations to relate local to UK mean extremes and apply the resulting relationships to climate model data in a risk-based attribution methodology. We find that temperatures above 35 °C are becoming increasingly common in the southeast, while by 2100 many areas in the north are likely to exceed 30 °C at least once per decade. Summers which see days above 40 °C somewhere in the UK have a return time of 100-300 years at present, but, without mitigating greenhouse gas emissions, this can decrease to 3.5 years by 2100.

随着欧洲热浪的加剧，英国（UK）的夏季也越来越热。英国于2019年7月在剑桥设定的创纪录的38.7°C的温度提出了一个问题，即现在是否可以超过40°C。在这里，我们展示了人类影响力如何增加局部超过30、35和40°C的可能性。我们利用观察结果将本地与英国的平均极端值联系起来，并在基于风险的归因方法中将所得关系应用于气候模型数据。我们发现东南部越来越多的温度高于35°C，而到2100年，北部的许多地区可能至少每十年一次超过30°C。在英国某个地方，夏季温度超过40°C的夏天，目前的返回时间为100-300年，但是，在不减少温室气体排放的情况下，该时间可以减少到3年。