The aim of this paper is to understand the historical and future climate change situation using 15 extreme precipitation indices in the Pare watershed of Arunachal Pradesh, India. Historical period (1981–2019) and future period (2021–2050) precipitation data are used to compute extreme precipitation indices in RClimDex software. The Pare watershed was divided into 13 subwatersheds; however, the results of the study showed no significant spatial variation. This study found that majority of the precipitation extreme indices are showing decreasing trends during the historical period and most of them are statistically insignificant at 95% confidence level. Only three indices such as SDII, CWD and MRI are found significant at 0.05 level in the Pare watershed. Though not significant, the annual precipitation amount in the Pare watershed was found decreasing at the rate of 3.3 mm per year during the study period. The trend analysis over the whole watershed indicated significant decreasing trends for CWD and MRI while indicating significant increasing trend for SDII. The representative concentration pathway (RCP) 4.5 and 8.5 projected the extreme precipitation indices in a very similar way. The results of the trend analysis under RCP 8.5 showed significant decreasing trend only at SW10 for the index-moderate rainfall index (MRI). Various cases of RX1DAY and RX5DAY not falling during the months of monsoon were observed in both the historical and future periods. The percentage departures of the monsoon from its annual total had increased in RCP 4.5 and RCP 8.5 scenarios as compared to the historical periods. The results of this climatic investigation suggest that the precipitation regime in the study area had been accompanied and also expected by overall reduction in precipitation amount, milder rainfall events, reduction in monsoon (June–September) rainfall and drier climatic conditions. With the prevalent historical scenario and future projected scenarios of the extreme precipitation indices, the water resource potential in the study area is expected to be greatly reduced, for which the authors seek the attention of various stakeholders in water and allied sectors to come together and discuss on the construction of water conservation structures so that agricultural activities can be expanded and remain sustainable.

本文旨在使用印度阿鲁纳恰尔邦的Pare流域中的15个极端降水指数来了解历史和未来的气候变化情况。在RClimDex软件中，使用历史时期（1981–2019）和未来时期（2021–2050）的降水数据来计算极端降水指数。Pare流域分为13个子流域；然而，研究结果表明没有明显的空间变化。这项研究发现，在历史时期内，大多数降水极端指数都显示出下降的趋势，并且在95％的置信水平下，大多数在统计上是微不足道的。在Pare流域中，只有三个指标（如SDII，CWD和MRI）在0.05水平上才有意义。虽然不重要，研究期间，Pare流域的年降水量以每年3.3 mm的速度减少。整个流域的趋势分析表明，CWD和MRI的趋势显着下降，而SDII的趋势则显着上升。代表性浓度路径（RCP）4.5和8.5以非常相似的方式预测了极端降水指数。在RCP 8.5下的趋势分析结果表明，仅在指数中等降雨指数（MRI）时，SW10才出现明显的下降趋势。在历史和未来时期都观察到了季风月份期间RX1DAY和RX5DAY并未下降的各种情况。与历史时期相比，RCP 4.5和RCP 8.5方案中季风与其年度总量的偏离百分比有所增加。该气候调查的结果表明，该研究区的降水状况是伴随而来的，并且也预期降水量的总体减少，降雨事件的温和，季风（6月至9月）降雨量的减少和气候条件的干燥。鉴于极端降水指数的普遍历史情景和未来预测情景，预计该研究区域的水资源潜力将大大减少，为此，作者寻求水和相关部门的各个利益相关者的关注，共同探讨建造节水结构，以扩大农业活动并保持其可持续性。