One of the most relevant and debated topics related to the effects of the climate change is whether intense rainfall events have become more frequent over the last decades. It is a crucial aspect, since an increase in the magnitude and frequency of occurrence of heavy rainfall events could result in a dramatic growth of floods and, in turn, human lives losses and economic damages. Because of its central position in the Mediterranean area, Sicily has been often screened with the aim to capture some trends in precipitation, potentially related to climate change. While Mann-Kendall test has been largely used for the rainfall trend detection, in this work a different procedure is considered. Precipitation trends are here investigated by processing the whole rainfall time-series, provided by the regional agency SIAS at a 10-min resolution, through the quantile regression method by aggregating precipitation across a wide spectrum of durations and considering different quantiles. Results show that many rain gauges are characterized by an increasing trend in sub-hourly precipitation intensity, especially at the highest quantiles, thus suggesting that, from 2002 to 2019, sub-hourly events have become more intense in most of the island. Moreover, by analysing some spatial patterns, it has been revealed that the south and the east of Sicily are more interested in significant increasing rainfall trends, especially at the 10-min duration. Finally, the comparison between the two procedures revealed a stronger reliability of the quantile regression in the trend analysis detection, mainly due to the possibility of investigating the temporal variation of the tails of precipitation distribution.

中文翻译：

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使用基于地中海地区分位数回归的多尺度方法检测降水趋势

与气候变化的影响相关的最相关和最具争议的话题之一是，在过去的几十年里，强降雨事件是否变得更加频繁。这是一个至关重要的方面，因为强降雨事件发生的幅度和频率的增加可能导致洪水的急剧增加，进而造成人员伤亡和经济损失。由于位于地中海地区的中心位置，西西里岛经常受到筛选，目的是捕捉降水的一些趋势，可能与气候变化有关。虽然 Mann-Kendall 检验主要用于降雨趋势检测，但在这项工作中考虑了不同的程序。这里通过处理由区域机构 SIAS 以 10 分钟分辨率提供的整个降雨时间序列来研究降水趋势，通过分位数回归方法，在广泛的持续时间范围内汇总降水并考虑不同的分位数。结果表明，许多雨量计的特点是亚小时降水强度呈增加趋势，尤其是在最高分位数处，这表明从 2002 年到 2019 年，该岛大部分地区的亚小时降水强度变得更加强烈。此外，通过分析一些空间模式，发现西西里岛南部和东部对显着增加的降雨趋势更感兴趣，尤其是在 10 分钟的持续时间。最后，两种程序的比较揭示了趋势分析检测中分位数回归的更强的可靠性，主要是由于调查降水分布尾部的时间变化的可能性。