Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
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Book Part Energy Production from Gas Hydrates(Elsevier, 2025) Çifçi, G.; Parlaktuna, M.; Çelebi, S.S.; Günaydın, S.O.Gas hydrates are a type of natural formation that contains large amounts of mostly methane, which is also known as natural gas, and water, in the form of ice. Methane hydrates are cages of water molecules that surround and trap methane molecules. Gas hydrate is geophysical, geologically and economically important for several reasons: Gas hydrates are good cap rocks for oil and natural gas. The methane hydrate itself is an important energy source. A volume of gas hydrate can store up to 164 times per volume of gas as zipped gas, and the fact that gas hydrate occurs almost all around the world. Methane seepage may indicate the existence of a deeper hydrocarbon reservoir, and the methane production and migration in the slope sediments may cause massive slope failure. Last but not least Methane gas has a minimum 22 times more global warm absorption capacity compared to carbon dioxide if it is released into the atmosphere. In other words, greenhouse gas is due to its contribution to climate change. Gas hydrates have drawn significant interest as a potential near future energy resource. Research in the production field of gas hydrates has focused on several key areas, including the feasibility of commercial production, the environmental impacts, and the technological improvements associated with the safe recovery of gas. © 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Uncertainty Assessment of the Impacts of Climate Change on Streamflow in the Iznik Lake Watershed, Türkiye(MDPI, 2026) Tezel, Anil Caliskan; Akpinar, Adem; Bor, Asli; Elci, SebnemStudy region: This study focused on the Iznik Lake Watershed in northwestern T & uuml;rkiye. Study focus: Climate change is increasingly affecting water resources worldwide, raising concerns about future hydrological sustainability. This study investigates the impacts of climate change on river streamflow in the Iznik Lake Watershed, a critical freshwater resource in northwestern T & uuml;rkiye. To capture possible future conditions, downscaled climate projections were integrated with the SWAT+ hydrological model. Recognizing the inherent uncertainties in climate models and model parameterization, the analysis examined the relative influence of climate realizations, emission scenarios, and hydrological parameters on streamflow outputs. By quantifying both the magnitude of climate-induced changes and the contribution of different sources of uncertainty, the study provides insights that can guide decision-makers in future management planning and be useful for forthcoming modeling efforts. New hydrological insights for the region: Projections indicate wetter winters and springs but drier summers, with an overall warming trend in the study area. Based on simulations driven by four representative grid points, the results at the Karadere station, which represents the main inflow of the watershed, indicate modest changes in mean annual streamflow, ranging from -7% to +56% in the near future and from +19% to +54% in the far future. Maximum flows (Qmax) exhibit notable increases, ranging from +0.9% to +47% in the near future and from +21% to +63% in the far future, indicating a tendency toward higher peak discharges under future climate conditions. Low-flow conditions, especially in summer, exhibit the greatest relative variability due to near-zero baseline discharges. Relative change analysis revealed considerable differences in Karadere and Findicak sub-catchments, reflecting heterogeneous hydrological responses even within the same basin. Uncertainty analysis, conducted using both an ANOVA-based approach and Bayesian Model Averaging (BMA), highlighted the dominant influence of climate projections and potential evapotranspiration calculation methods, while land use change contributed negligibly to overall uncertainty.Book Part Citation - WoS: 2Citation - Scopus: 4Issues and Challenges in Sustainable Usage of Groundwater Resources in Afghanistan(Springer Nature, 2025) Zaryab, Abdulhalim; Nazari, Aref; Farahmand, Asadullah; Yaqubi, Mohammad Saber; Mirzad, Sayed Mohammad Mansoor; Jafari, Zamen; Shams, Ajmal KhanGlobally, Afghanistan is currently a frontrunner in groundwater scarcity due to unplanned urbanization, rapid rise in population, climate change, weak policies, mismanagement, and lack of long-term vision. Frequent weather extremes like droughts and floods and prolonged war and political instability lead the country far away from achieving water security, food reliance and sustainable management of its natural resources. The war situation also refrains in gathering of long-term hydrological data and thus, there is a huge gap in understanding the water resources even better. Furthermore, aids from international organizations are limited in groundwater development and management. This chapter highlights various issues and challenges in sustainable usage and the importance of groundwater in the country. The chapter compiles the research carried out with regard to Afghanistan's quest to manage its groundwater resources more efficiently.Article Citation - WoS: 3Citation - Scopus: 2Assessing the Spatial and Temporal Characteristics of Meteorological Drought in Afghanistan(Birkhauser, 2025) Tayfur, G.; Hayat, E.; Safari, M.J.S.Afghanistan is suffering from periodic events of drought, which has exacerbated in recent years due to extreme climate events in the region. Having an arid to semi-arid climate, the country faces significant challenges of water resources management, especially for irrigation as reliance on agriculture is cumbersome. This study is undertaken to characterize historical meteorological drought in Afghanistan to provide an insight on where and when meteorological drought events happened in different River Basins (RBs). The study mainly employs the gamma-Standardized Precipitation Index (gamma-SPI) to analyze historical meteorological droughts across Afghanistan from 1979 to 2019. Monthly precipitation data is obtained from the Ministry of Energy and Water (MEW) of Afghanistan, which is a combination of observed data from ground stations and gap-filled data by the MEW for the study period. Gridded gamma-SPI values are interpolated and mapped to visualize patterns of spatial drought across the entire country. The results indicate that countrywide extreme drought events occurred in 1999, 2000, 2001, 2010, 2016, 2017, and 2019, particularly affecting southern, western, and southwestern regions. Decreasing rainfall occurred in all five RBs, with the most considerable decline observed in the 1999–2008 period. The study reveals the increasing frequency and severity of meteorological droughts in Afghanistan. It also emphasizes on the vulnerability of agriculture and water sectors due to the drought events. The findings of the study suggest the need for better drought monitoring, preparedness, awareness, and adaptation of strategies to ensure water security and agricultural sustainability in the face of climate change. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.Book Part An Effect of Climate Change: Increased Health Risks Due To Arsenic in Drinking Water - the Case of İzmir, Turkey(Nova Science Publishers, Inc., 2010) Sofuoglu, S.C.; Sofuoglu, A.Our previous research (Kavcar et al., 2009) has shown that tap water arsenic concentrations in the City of İzmir, Turkey, was of concern as arsenic in 15 of 37 (41%) of the tap water samples (collected in the year 2004) exceeded the Turkish drinking water standard of 10 µg/L (TMH, 2005). The median, mean, and 95th percentile concentrations were 2.9, 12.0, and 42.0 µg/L, respectively. The violations of the standard were in three districts, i.e., Bornova, Çiğli, and Karşıyaka, that were served primarily by groundwater sources. The concentrations in other districts were below the standard. However, concentrations less than the standard may be associated with a carcinogenic risk that is greater than the acceptable risk level of one in ten thousand depending on the level of exposure, mainly, daily drinking water intake rate and body weight. This was the case for the City of İzmir as lifetime carcinogenic risks exceeded the acceptable level for 19 of the 37 participants (51%). As the result of the above cited research, the local government has shut-down a number of groundwater wells as a mitigation measure. In turn, the concentrations were brought down to <15 µg/L in the three districts by increasing the proportion of surface water supplied from Tahtalı Reservoir. However, climate change has been affecting the region. The water volume in the resevoir was dropped below 5% in 2008. As a result, the arsenic contaminated wells were brought back into the service, causing a sharp increase in the arsenic concentrations, this time all around the city, measured by the local health authority. İzmirians who can not afford to buy bottled drinking water are (to be) exposed to arsenic concentrations of 30-40 µg/L until the planned treatment plant is in place. A probablistic risk assessment was conducted to estimate the human health risks for the scenario of no available surface water, in which no treatment and treatment with 90% and 99% efficiencies were assumed for the arsenic contaminated groundwater, based on the concentrations measured by the local health authority. The median carcinogenic risk estimated for the scenario of no treatment for the metropolitan area was approximately eight times the median value estimated when the main source water was Tahtalı Reservoir, a surface water dam. © 2008 Nova Science Publishers, Inc.