Optimizing Water Allocation in a Changing Climate Utilizing WEAP and SSP5.85 Scenarios- A Case Study: Keshan Chai basin

نویسندگان

1 دانشجوی دکترای آب و هواشناسی، دانشگاه اصفهان

2 گروه مهندسی عمران، دانشگاه آزاد اسلامی واحد جلفا

3 دانشکده فنی، گروه مهندسی عمران، دانشگاه آزاد تبریز

doi
10.22034/ceej.2025.66162.2420
چکیده

This study investigates the potential effects of the Isar Dam on the water resources of a specific basin, considering the growing concern of climate change. This research comprehensively assesses the impacts of climate change on the Keshan Chai basin by integrating advanced methods such as the WEAP model, the SSP5.85 scenario of the IPCC Sixth Assessment Report, and Landsat satellite imagery an analysis of historical data reveals significant fluctuations in water flow within the Ravasjan River, likely caused by repeated occurrences of floods and droughts. To address these variations and ensure a more stable water supply, the Isar Dam is projected to deliver regulated water for various purposes: 14 million cubic meters annually for drinking water, 35 million cubic meters annually for agriculture, and 4 million cubic meters annually for environmental needs. Climate change simulations project a 5% increase in annual precipitation for the forecast period (2025-2065) compared to the observation period (1990-2020), raising concerns about increased flooding in the region. The study also identifies three distinct climatic types based on monthly precipitation distribution. The minimum environmental flow requirement is estimated at 5.0 cubic meters per second monthly. Scenario-based water demand modeling shows that in Scenario 1, 92% of Ozghan’s demand and 47% of the development networks are met in 70% of cases, with full satisfaction in 30%. Scenario 2 achieves 90% and 45% in 70% of cases, fully met in 25%. Scenario 3 meets 77% and 38% in 70% of cases, with 23% full satisfaction. Precipitation variability between 2011 and 2020 has created challenges for water management. Principal component analysis indicates 62.19% and 15.98% of precipitation variance are explained.