Global climate change is a phenomenon resulting from the complex interaction of human influences and natural factors. These changes lead to imbalances in climate systems as human activities such as greenhouse-gas emissions increase atmospheric gas concentrations. This situation affects the frequency and intensity of climate events worldwide, with floods being one of them. Floods manifest as water inundations due to factors such as changes in rainfall patterns, rising temperatures, erosion, and sea-level rise. These floods cause significant damage to sensitive areas such as residential areas, agricultural lands, river valleys, and coastal regions, adversely impacting people's lives, economies, and environments. Therefore, flood risk has been investigated in decision-making processes in the Diyarbakır province using the analytical hierarchy process (AHP) method and future disaggregation of global climate model data. HadGEM-ES, GFDL-ESM2M, and MPI-ESM-MR models with RCP4.5 and RCP8.5 scenarios were used. Model data were disaggregated using the equidistance quantile matching method. The study reveals flood-risk findings in the HadGEM-ES model while no flood risk was found in the GFDL-ESM2M and MPI-ESM-MR models. In the AHP method, flood risk analysis was conducted based on historical data across Diyarbakır and interpreted alongside future rainfall data.

Küresel iklim değişikliği, her geçen gün Dünya genelinde daha fazla etkisini artırarak tehlikeli sonuçlara neden olmaktadır. Özellikle iklim değişikliği kaynaklı şiddetli yağışlar, sel felaketlerine yol açmaktadır. Bu sel olayları, can kaybına ve maddi hasara neden olabilmektedir. Bu nedenle, çeşitli önleyici çalışmalar yürütülmektedir. Bu çalışmalardan biri, Yağış Şiddeti-Süre-Frekans (IDF) eğrilerinin oluşturulmasıdır. Ancak bu eğriler genellikle geçmiş tarihsel verilere dayandığından, gelecek için kullanılmaları uygun görülmemektedir. Bu nedenle, bu çalışmada iklim modeli verileri ve ayrıştırılmış yağış verileri kullanılarak iklim değişikliğini de içeren geleceğe yönelik yeni IDF eğrileri elde etmek için farklı yöntemler kullanılmıştır.

Global climate change leads to significant alterations in climate systems, affecting natural resource management, agriculture, and water security. As these impacts are also felt at the local level, regional climate analyses are crucial. This study analyzes precipitation data from Diyarbakır province between 1970 and 2022 to examine the local effects of climate change. Trend analyses were conducted using Mann-Kendall, Sen's Slope, Spearman’s Rho, and Innovative Trend Analysis (ITA) methods. The Mann-Kendall test assessed the statistical significance of trends, while Sen's Slope estimated the magnitude of these trends. The results indicated no statistically significant trends on an annual or seasonal basis. However, the ITA method revealed decreasing trends in summer precipitation and annual totals, alongside increasing trends in spring and autumn precipitation. No trends were detected for winter precipitation. The Spearman’s Rho test identified a positive relationship between annual total precipitation and seasons, but no trends were observed among the seasons themselves. This study highlights the importance of local climate analyses and contributes to preparedness for future changes. Continuous monitoring of climate data plays a critical role in making informed strategic decisions, particularly in water resource management and agricultural policies.

Groundwater is an important component of the hydrological cycle and a critical resource for ecosystems and human life on Earth. Estimation of groundwater levels is important for strategic planning and management in many areas such as agriculture, industry, engineering studies, and drinking water. In particular, it is necessary to determine the groundwater accurately and clearly in order to carry out both ground and hydraulic works. In this study, the estimation of the groundwater level of Diyarbakır province was made by analytical hierarchy method. Groundwater level estimation was made using slope, geology, geomorphology, land use, precipitation, fault density, drainage density classes. Especially in areas where data supply is short, positive and accurate results can be obtained with AHP, which is a fast and practical application. It is expected that the findings obtained will benefit public and private institutions and organizations for future studies.

Climate change alters precipitation regimes, affecting flood hazard and sustainable urban development. This study assesses flood exposure of planned development and emergency assembly areas in Bismil and Çınar, Diyarbakır, Turkey, for 2023–2048. Precipitation projections from HadGEM2-ES, MPI-ESM-MR, and GFDL-ESM2M in RCP4.5 and RCP8.5 were bias-corrected using Equidistant Quantile Mapping (EQM) to develop intensity–duration–frequency (IDF) curves. HEC-HMS generated 100-year design hydrographs, HEC-RAS 2D simulated flooding, and GIS-based overlay analyses quantified exposure. In Çınar, maximum water depths ranged from 2.64 to 4.22 m, and inundation areas from 0.300 to 0.383 km². In HadGEM2-ES RCP8.5, exposed planned development areas increased from a reference value of 0.117 to 0.128 km², while exposed emergency assembly areas increased from 0.033 to 0.035 km². In Bismil, maximum water depths ranged from 6.39 to 7.41 m, and inundation areas from 4.320 to 5.932 km²; no overlap occurred with the evaluated development or assembly areas under any scenario. However, this absence does not imply that other parts of Bismil face no flood hazard. These differences highlight the need for district-specific exposure assessments. The framework identifies exposed development and assembly areas, supporting climate-adaptive land-use planning and sustainable urban resilience.