Control of recent European surface climate change by atmospheric flow

International audienceMany changes in European surface climate have occurred over the past decades, but most of the processes driving them are not identified. In particular, the role of atmospheric flow in driving surface trends needs to be evaluated to better predict future regional climate. We compare observed surface climate trends with those constructed from daily flow analogues. We find that during the last 60 years atmospheric circulation changes are the main drivers of surface weather trends in winter, but not in summer where temperature strongly interacts with the water cycle. For instance, increasing anticyclonic conditions control the decreasing summer rainfall frequency, but rainfall amount and cloud cover have not decreased accordingly, because individual rainfall events bring more rain now than decades ago. Over the past three decades the control by atmospheric flow changes has weakened, indicating evolutions in the processes steering European surface climate change