Thomas Jobin, Rohith A N, Sebastian Dawn Emil, Nizar Sinan, Jainet P J, Vema Vamsi Krishna, Sudheer K P
Geology and Geological Engineering, University of Mississippi, Oxford, 38655, MS, USA.
Department of Civil Engineering, Indian Institute of Technology Delhi, Hauz Khas, 110 016, India; Department of Agricultural and Biological Engineering, The Pennsylvania State University, State College, 16802, PA, USA; Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, 600 036, India.
J Environ Manage. 2025 May;381:125252. doi: 10.1016/j.jenvman.2025.125252. Epub 2025 Apr 6.
Recent changes in global precipitation patterns have led to unparalleled floods, landslides, and droughts, significantly impacting lives, infrastructure, and the environment. Understanding regional-scale climate change impacts on hydrological responses has attracted researchers, primarily using climate projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6). This study focuses on the southern Western Ghats (SWG) and western coastal plains (WCP) of the Indian subcontinent to assess climate change impacts on regional hydrology. By analyzing climate data from nine CMIP6 General Circulation Models (GCMs) and simulating hydrological fluxes with the Variable Infiltration Capacity (VIC) model, we demonstrate that all models robustly project an intensification of the hydrological cycle due to climate warming under two shared socioeconomic pathways (SSPs) - SSP245 and SSP585 - especially during the Indian Summer Monsoon (ISM) season. The region is projected to experience up to a 20 % increase in annual precipitation per 1 °C rise in temperature, with extreme precipitation events (EPEs) potentially increasing by up to 16 % per degree of warming. Future runoff is expected to rise under both SSP scenarios, with watersheds experiencing markedly wetter ISM season and drier pre-monsoon (PRM) season compared to the baseline period, leading to risks associated with concurrent floods/landslides and droughts. These changes underscore the necessity for region-specific adaptation strategies to manage water resources effectively. Adaptation strategies to enhance short-term water storage during the ISM season could partially mitigate water shortages during the PRM season, offering potential benefits in the wake of climate change. Our findings highlight the need for integrated water resources management plans to address the challenges posed by climate change, ensuring sustainable water availability, agricultural productivity, and hydropower generation.
全球降水模式最近的变化导致了前所未有的洪水、山体滑坡和干旱，对生命、基础设施和环境产生了重大影响。了解区域尺度气候变化对水文响应的影响吸引了研究人员，他们主要使用耦合模式比较计划第6阶段（CMIP6）的气候预测。本研究聚焦于印度次大陆的西高止山脉南部（SWG）和西部沿海平原（WCP），以评估气候变化对区域水文的影响。通过分析来自9个CMIP6通用环流模型（GCMs）的气候数据，并使用可变下渗能力（VIC）模型模拟水文通量，我们证明，在两种共享社会经济路径（SSPs）——SSP245和SSP585——下，所有模型都有力地预测，由于气候变暖，水文循环将加剧，尤其是在印度夏季风（ISM）季节。预计该地区温度每升高1°C，年降水量将增加20%，极端降水事件（EPEs）可能每升温1°C增加16%。在两种SSP情景下，未来径流预计都会增加，与基准期相比，流域的ISM季节将明显更湿润，季风前（PRM）季节将更干燥，从而导致洪水/山体滑坡和干旱并发的风险。这些变化凸显了制定针对特定区域的适应策略以有效管理水资源的必要性。在ISM季节增强短期蓄水的适应策略可以部分缓解PRM季节的水资源短缺，在气候变化的背景下带来潜在益处。我们的研究结果强调了制定综合水资源管理计划以应对气候变化带来的挑战的必要性，确保可持续的水资源供应、农业生产力和水力发电。
