Long-term instrumental series are crucial to analyse extreme air temperature indices and to examine modern climate warming within a historical context. This research provides the first assessment in Ireland of the frequency, duration, intensity and geographical distribution of the daily extreme air temperature indices recommended by the ETCCDI (Expert Team on Climate Change Detection and Indices) and based on long-term rescued, quality-controlled and homogenised data. Prior analysis of air temperature indices in Ireland had focused on the period since the second half of the 20th century, where digital data were readily available. Earlier estimations of long-term air temperature trends in Ireland focused on non-homogenised data from a small network of stations. For this research, 11 long-term (1885–2018) maximum and minimum air temperature series were analysed to assess seasonal and annual trends and construct extreme air temperature indices in Ireland. The non-parametric Mann-Kendall test was employed to test the statistical significance of the maximum and minimum air temperatures and indices trends (p < 0.05). Significant increasing trends were assessed in the seasonal and annual maximum and minimum air temperature series in Ireland, with greater increases in the spring and autumn seasons. Significant increasing trends were determined in the warm days (+6.8 days), warm nights (+7.5 nights), warm spell duration index (+3.9 days), growing season length (+22 days), coldest night (+2.7 °C) and coldest day (+1.5 °C) in the period 1885–2018 in Ireland. In the same period, significant decreasing trends were identified in the cold days (−9.3 days), cold nights (−7 nights), frost days (−13.7 days), cold spell duration index (−6.9 days) and diurnal air temperature range (−0.1 °C) in Ireland. The results follow global patterns presented in the Six Assessment Report of the Intergovernmental Panel on Climate Change. The findings of this research will be crucial to assist stakeholders and policymakers in defining climate action, adaptation and mitigation plans in response to shifting trends in air temperature extremes.

长期仪器系列对于分析极端气温指数和在历史背景下检查现代气候变暖至关重要。这项研究在爱尔兰首次评估了 ETCCDI（气候变化检测和指数专家小组）推荐的每日极端气温指数的频率、持续时间、强度和地理分布，并基于长期救助、质量控制和同质化的数据。之前对爱尔兰气温指数的分析主要集中在 20 世纪下半叶以来的时期，当时数字数据很容易获得。早期对爱尔兰长期气温趋势的估计侧重于来自小型站点网络的非均匀数据。对于这项研究，分析了 11 个长期（1885-2018 年）最高和最低气温系列，以评估季节和年度趋势并构建爱尔兰的极端气温指数。采用非参数 Mann-Kendall 检验来检验最高和最低气温和指数趋势的统计显着性 (p < 0.05)。在爱尔兰的季节和年度最高和最低气温系列中评估了显着增加的趋势，春季和秋季的增加幅度更大。暖天（+6.8 天）、暖夜（+7.5 夜）、暖期持续时间指数（+3.9 天）、生长季节长度（+22 天）、最冷夜（+2.7 °C）的显着增加趋势和 1885-2018 年间爱尔兰最冷的一天 (+1.5 °C)。在同一时期，在寒冷的日子（-9.3 天）、寒冷的夜晚（-7 夜）、霜冻天数（-13.7 天）、寒流持续时间指数（-6.9 天）和昼夜气温范围（-0.1 °C）中发现了显着下降的趋势） 在爱尔兰。结果遵循政府间气候变化专门委员会六次评估报告中提出的全球模式。这项研究的结果对于帮助利益相关者和政策制定者制定气候行动、适应和缓解计划以应对极端气温变化趋势至关重要。