Early Summer Soil Moisture Contribution to Western European Summer Warming

Warm European summer temperatures are often preceded by low soil moisture conditions, but also depend on the atmospheric circulations and associated rainfall that may trigger drought to persist land-atmosphere feedbacks take place. The quantitative role of early (ESSM) trends, versus trends in other large-scale drivers (LS), explaining long-term warming have not been investigated so far. Using regional climate simulations with forced circulation different possible initial moisture, we show increasing ESSM deficit explains almost all trend (1980–2011) Western Europe (?0.1–0.2°C.decade?1, p-value < 0.05). It contributed a similar amount Eastern Europe, although here LS much larger part overall warming. Our results emphasize crucial pre-summer water cycle current future evolutions climate.