Stefan Rahmstorf and Dim Coumou from the Potsdam Institute for Climate Impact Research develop a theoretical approach to quantify the effect of long-term trends on the expected number of extreme events in time series. They apply this method to study the impact of warming trends on heat records. The study finds that the number of record-breaking events increases approximately in proportion to the ratio of the warming trend to short-term standard deviation. Short-term variability decreases the number of heat extremes, while climatic warming increases it. For extremes exceeding a predefined threshold, the dependence on the warming trend is highly nonlinear. The sum of warm and cold extremes increases with any climate change, whether warming or cooling. They estimate that climatic warming has increased the number of new global-mean temperature records expected in the last decade from 0.1 to 2.8. For Moscow's July temperature, the local warming trend has increased the number of records expected in the past decade fivefold, implying an approximate 80% probability that the 2010 July heat record would not have occurred without climate warming. The study highlights the significant impact of climatic warming on the frequency and intensity of extreme events.Stefan Rahmstorf and Dim Coumou from the Potsdam Institute for Climate Impact Research develop a theoretical approach to quantify the effect of long-term trends on the expected number of extreme events in time series. They apply this method to study the impact of warming trends on heat records. The study finds that the number of record-breaking events increases approximately in proportion to the ratio of the warming trend to short-term standard deviation. Short-term variability decreases the number of heat extremes, while climatic warming increases it. For extremes exceeding a predefined threshold, the dependence on the warming trend is highly nonlinear. The sum of warm and cold extremes increases with any climate change, whether warming or cooling. They estimate that climatic warming has increased the number of new global-mean temperature records expected in the last decade from 0.1 to 2.8. For Moscow's July temperature, the local warming trend has increased the number of records expected in the past decade fivefold, implying an approximate 80% probability that the 2010 July heat record would not have occurred without climate warming. The study highlights the significant impact of climatic warming on the frequency and intensity of extreme events.