A Climatology of Heatwaves Over Greece for the Period 1960–2022

ABSTRACT The Mediterranean region is highly vulnerable to the impacts of climate change including Heatwave Events (HEs). Greece in particular, has experienced the effects of such events across various sectors, including public health, the environment, energy, and the socio‐economic domain. This study presents a climatology of HE over Greece from 1960 to 2022 utilising data from 67 weather stations operated by the Hellenic National Meteorological Service (HNMS). The frequency, duration, and severity of HE are analysed using statistical methods including trend and changepoint analysis. To better understand the intensity of HEs, they are classified into five intensity categories (ICs) based on percentile‐based thresholds of the maximum daily temperature. In addition, the interannual, seasonal and monthly occurrence of HEs is examined and compared across seven distinct climate regions of Greece. The findings reveal positive trends in heatwave frequency (HF) in almost 80% of the stations across Greece and across all ICs particularly during spring and summer. Furthermore, heatwave duration (HD), mostly during summer and autumn, and heatwave severity (HS), mostly during spring, exhibited the same behaviour, although with lower percentages compared to HF. Negative trends in HS are observed at a small number of stations. Spatial analysis indicates that the most affected regions by HEs are northern and western Greece, although changes are observed throughout the country. Finally, changepoint analysis using Pettitt's test reveals significant changes in HF and HD between the 1970s and 2010s. Additionally, the number of stations showing significant changes decreases as the intensity of ICs increases.