Abstract. In this study we analyze the drought features at European level over the period 1901–2019, using three drought indices: the Standardized precipitation (SPI), the Standardized Precipitation Evapotranspiration Index (SPEI) and the self-calibrated Palmer Drought Severity Index (scPDSI). The results based on the SPEI and scPDSI indices point out to the fact that central Europe (CEU) and the Mediterranean region (MED) are becoming dryer, due to an increase in the potential evapotranspiration and the mean air temperature, while the northern part of Europe (NEU) is becoming wetter. By contrast, the SPI drought index does not reveal these changes in the drought variability, mainly due to the fact that the precipitation does not exhibit a significant change, especially over CEU. SPEI12 indicates a significant increase both in the frequency and area over the last three decades for MED and CEU, while SPI12 is not capturing these features. By analyzing the joint probability of compound events (e.g. high temperatures/droughts), we show that the potential evapotranspiration and the mean air temperature are becoming essential components for drought occurrence over CEU and MED. This, together with the projected increase in the potential evapotranspiration under a warming climate, has significant implications concerning the future occurrence of drought events, especially for MED and CEU regions.

中文翻译：

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过去120年欧洲干旱水平的变化

摘要。在这项研究中，我们使用三个干旱指数来分析1901-2019年期间欧洲水平的干旱特征：标准化降水（SPI），标准化降水蒸散指数（SPEI）和自校准的帕尔默干旱严重性指数（scPDSI） 。基于SPEI和scPDSI指数的结果表明，由于潜在的蒸散量和平均气温的上升，中欧（CEU）和地中海地区（MED）变得越来越干燥，而欧洲（NEU）变得越来越湿。相比之下，SPI干旱指数并未显示出干旱变异性的这些变化，这主要是由于降水没有显示出显着变化的事实，尤其是在CEU上。SPEI12表示，在过去的三十年中，MED和CEU的频率和面积都显着增加，而SPI12并未捕捉到这些功能。通过分析复合事件（例如高温/干旱）的联合概率，我们表明潜在的蒸散量和平均气温正在成为CEU和MED上发生干旱的重要组成部分。这，加上气候变暖下潜在的蒸散量的预计增加，对未来干旱事件的发生具有重大影响，特别是在地中海和中欧地区。我们表明，潜在的蒸散量和平均气温正在成为CEU和MED上发生干旱的重要组成部分。这，加上气候变暖下潜在的蒸散量的预计增加，对未来干旱事件的发生具有重大影响，特别是在地中海和中欧地区。我们表明，潜在的蒸散量和平均气温正在成为CEU和MED上发生干旱的重要组成部分。这，加上气候变暖下潜在的蒸散量的预计增加，对未来干旱事件的发生具有重大影响，特别是在地中海和中欧地区。