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Hidrolojik modelleme sistemi HEC-HMS kullanılarak akış debisinin simülasyonu
Basin models are fundamental for water resources assessment, analyzing quality and quantity of streamflow, managing water distribution systems, protecting and developing groundwater systems, flood protection, and water-supply forecasting. The integration of all hydrologic processes with their interconnections to each other at the basin scale is required for basin models. Mathematical basin models such as HEC-HMS are used for simulating hydrological processes in basin-scale to understand basin response to storm events. The goal of this study is to test the applicability of the HEC-HMS model for a basin located in Turkey and to demonstrate the importance of snowmelt especially for snow affected areas, such as Çakıt Basin which is the study area of this thesis. Requirements of event-based and continuous simulations are identified to guide future HEC-HMS applications in Turkey. Çakıt Basin, which is located in Niğde province has a drainage area of 518 km2. Meteorological data, flow data, digital elevation model, land use/land cover map and soil properties are collected and used in building event-based and continuous models. The models are calibrated and validated with observation stations constructed within the scope of 115Y041 TUBITAK project. The results of this study showed that streamflow at Çakıt Stream Gage Station, both for event-based and continuous runs, can be estimated realistically with NSE values higher than 0.6 for the validation periods using HEC-HMS. Furthermore, the importance of integration of the snowmelt into the hydrologic models is demonstrated.
Ekosistemler üzerindeki antropojenik etkiler için bir sınır arayışı: "Adil enerji kullanımı"
The physical scale of material and energy throughput of human activity continues to threaten the critical natural boundaries of the ecosystem. Energy efficiency and decarbonization efforts are not alone sufficient to counterbalance the impacts of fast-growing demand due to population and economic growth. Further, efficiency improvements often come with rebound effects that offset achievements. In order to carry the human activities within safe boundaries, a limit to total throughput could be targeted. We need to increase human well-being without increasing energy consumption to the ecologically dangerous levels. This could partly be possible by technological efficiency improvements and conservation. On the other hand, it could also be achieved by re-distributing the total available energy resources in the society. In our study, we attempt to develop an approach for measuring a benchmark which may be used to identify excessive uses of energy that do not lead to significant increases in well-being. We call this the "fair energy use level", for the reason that it also refers to energy justice. We investigate decoupling between energy consumption and some quality of life indicators at the country level via cross-sectional analysis. Different from previous studies, we use residential energy consumption instead of primary energy consumption as it tends to mask the true responsibility of a country. In order for a fair comparison of countries' energy-wellbeing performances, we corrected energy consumption data for climatic differences and excluded energy-rich countries and biomass dependent countries to control for resource endowment and energy quality. Using the "knee" (maximum curvature) of the function we were able to compute the point after which well-being improvements are negligible. We find approximate levels of per capita energy consumption which could be considered as a boundary for "fair use" under certain conditions.
Gelişmekte olan ülkelerin enerji politikalarında ve iklim değişikliği azaltımı stratejilerinde nükleer enerjinin rolünün değerlendirilmesi
Nuclear energy is considered as one of the climate change mitigation options in the energy supply sector by substituting electricity generated from base load fossil fueled power plants reducing GHG emissions. Internalizing the costs of CO2 emissions provides an additional economic incentive for investment in nuclear energy both in developed and developing countries. While developed countries with stable energy demand are focused on the robustness and resilience of their energy systems, the priority of developing countries continues to be the strengthening of energy security in order to supply their increasing energy demand. Climate change is one of the major global commons problems of our society which requires long-term and ambitious strategies in order to transform the socioeconomic development to low-carbon energy pathways. The role of nuclear energy in transformation of the energy sector has been assessed by the climate change community on regional and global scales using various integrated assessment models. However there is a gap between the results of these studies and the quantitative commitments of countries for climate change mitigation in their NDCs submitted to the UNFCCC resulting in higher GHG emissions. In this study I show that the role of low-carbon energy supply options for climate change mitigation depends on global socioeconomic development pathways especially for developing countries already facing a transition in their economies and energy systems. The role of nuclear energy for supplying the electricity required for developing countries is dependent on global socio-economic pathways supporting investment in most stringent GHG emissions scenarios. Expert elicitation was used for MCA of energy supply system modeling results by integrating CO2 emissions from power sector, flexibility of the electricity grid to supply peak load demand, change in welfare from carbon tax and transfer of revenues for subsidizing renewable energy, and the total discounted energy system costs. The results show that for the second commitment period of the Paris Agreement, the role of nuclear energy is for supporting the transition of the energy system to a low carbon future for both green transformation and regional rivalry scenarios.
Türkiyenin Doğu Karadeniz ve Akdeniz bölgelerindeki sağanak yağışlı hava olaylarını tahmin etmek için oluşturulan WRF modeli duyarlılık ve deniz yüzey sıcaklığı analizleri
With this thesis it is aimed to enhance the prediction accuracy of the Weather Research and Forecasting (WRF) model on the extreme precipitation events of Mediterranean and Eastern Black Sea regions of Turkey. While the first part of sensitivity analysis was conducted for the physical parameters (microphysics, cumulus and PBL) and the initial boundary conditions, the second part has only focused on the impact of sea surface temperature (SST). After choosing 4 microphysics, 3 cumulus, 2 PBL and 2 input meteorological sources options, in total 96 scenarios have been tested through the first part of sensitivity analysis for each region. Among all of the schemes, generally for microphysics Eta / Ferrier (ES) scheme, for cumulus Grell Freitas (GFES) sheme and finally for PBL Mellor Yamada Janjic (MYJ) scheme performed better than the other options in Mediterranean event cases. However, for Eastern Black Sea region, Aeresol Aware Thomspon (AATS) and WRF Single Moment 6 (WSM6) as microphysics, Betts Miller Janjic (BMJ) and GFES as cumulus and MYJ as PBL scheme become prominent. Again, WRF model usually performs better by using the Global Forecasting System (GFS) meteorological input dataset in Mediterranean region whereas it produces more realistic forecasts for Eastern Black Sea, if it uses ERA5 Reanalysis (ERA5, ECMWF) meteorologic data. For SST analysis, three SST data sources were selected to use. Through detailed examination, the Medspiration and NCEP sources were found successful for the prediction of the Mediterranean event cases. In Eastern Black Sea region, the two satellite based sourced datasets (Medspiration and GHRSST) performed better than the other two.
Ankara çatı üstü güneş teknik fotovoltaik potansiyeli: Ön çalışma
Cities are responsible for over two-thirds of total energy consumption due to the population's externalities. The buildings in the urban areas cause half of this energy consumption. 250 cities have 100% renewable energy target worldwide, including nineteen metropolitans such as London, Los Angeles, Tokyo, and Paris. Besides, these metropolitans aim at zero emissions in new buildings by 2030 and in the existing ones by 2050. By year of 2018, as a developing country, Turkey has a dependency ratio of 73.8 % for overall energy and 51.11% for electricity. In order to overcome problems like population-based pressure in cities and energy security, Turkey requires effective and realistic renewable energy solutions that can combat climate change. As policymakers emphasize, more decentralized solutions as city-wide and municipality-based policies, would provide faster and more effective results to reach renewable energy targets. The renewable energy potential is not the same for all cities. Although there are some rooftop technical solar PV potential studies in country-wide, one of the main motivations of this study is to focus on both building types and roof types to generalize for a city. We develop an accurate methodology to determine the rooftop technical PV potential reliable and applicable to every type of roofs. City of Ankara is a convenient starting point for this study due to its relatively high solar irradiance, high number of public buildings and increasing energy demand. In the study, buildings in Ankara divided into three categories: residential, public, and commercial (shopping mall). After the manual selection, the methodology is applied using a well-known Helioscope software program and suitable area constants (access factors) are determined for the three categories. Constant value method was used to generalize the constants to all buildings. The results indicate that the Mono-Si module application is the optimum one for both pitched-roof and flat-roof apartments. Bifacial modules have better results for detached houses, public buildings, and shopping malls, and the amount of energy production might be increased by row-spacing arrangement specifically to the building.
Türkiye'de biyoçeşitlilik izleme çalışmalarının temel biyoçeşitlilik değişkenleri çerçevesinde değerlendirilmesi
The survival of species, habitats, ecosystems and thus the welfare of humankind are increasingly under threat due to adverse effects of land use change, overexploitation, pollution, invasive species and climate change. Monitoring biodiversity, understanding environmental responses and analyzing trends enable us to develop urgent actions for combatting biodiversity decline, and to improve policies to cope with these global challenges. Biodiversity observation has a long history. However the dispersed structure of knowledge, uneven distribution of existing data, and the lack of coordination between nations hamper effective harmonization. Furthermore, promising technological improvements and open source resources extend the biodiversity data landscape. Essential Biodiversity Variables (EBVs) which are a set of indicators for the standardized surveillance of biodiversity change, were developed by the Group on Earth Observations Biodiversity Observation Network in 2013 for interoperability of data. In this study, I explored the suitability of EBVs, considering the accumulated academic knowledge and the existing monitoring expertise in Turkey. By assessing the status of biodiversity monitoring, I identify spatial, temporal, taxonomic gaps. Then, a feasibility methodology was developed to prioritize the EBVs. Remote sensing plays a significant role in ecosystem monitoring globally as it is cheap, easily accessible, highly accurate and provides long term data delivery. However the utilization of this technology is not yet sufficient at the national level. I also demonstrate an example of using remotely sensed data in habitat mapping for monitoring purposes. I executed this study in sparse Mediterranean forests where several anthropogenic factors together with fires and droughts are shaping the ecosystem structure and composition.
Almanya ve Türkiye'de düşük karbonlu enerji dönüşümünün analizi
Long-term structural changes in energy systems, commonly referred as "energy transition", have occurred in the past and still occur worldwide. This global energy transition is being observed in multiple fields. Energy systems driven by fossil fuels is being gradually replaced by more decentralized, decarbonized, innovative and technologically smarter alternatives. This desired low-carbon system is mainly shaped by climate change mitigation and adaptation efforts. This inevitable transition to low-carbon economy has immense implications globally and indirectly force all countries to rethink their energy policies. In this regard, Germany is an important case study to observe the effects and management of this transition and a great example for other countries to learn from past experiences and prepare themselves for potential challenges. This research highlights how energy transition in Turkey, a growing economy which started restructuring its energy sector since 2002 through a variety of interlinked measures, is shaped and moving forward. The process is compared to mature German experience, "Energiewende" which is often regarded as the front runner in the global energy transition. The proposed multidimensional analysis focuses on energy security, economic and environmental motives of this transition. This analysis discusses whether Energiewende is a unique model towards low carbon or a model that can be extended to Turkey.
Makine öğrenmesi teknikleri kullanarak güneş aktivitesi, kozmik ışınlar ve dünya iklimi arasındaki ilişkilerin analizi
The Earth's climate is part of a complicated system that can be affected by many different parameters, both internal and external. Important external forces on the climate are galactic cosmic rays (GCR) and the Sun. Some research has already been conducted to investigate the relationship between the climate and external forces such as the GCR and solar activity. However, the relations are quite complicated and buried into almost chaotic meteorological measurements. This thesis looks deeper into the interactions between them. The parameters used in the correlation analysis are GCR flux, Sunspot number (SSN), total solar irradiance (TSI), UV irradiance (UVI), and the Oceanic Niño Index (ONI) as the predictor variables; total cloud amount (TCA), low cloud amount (LCA), global mean temperature anomaly (GMTA), aerosol optical depth (AOD) and precipitation as the response variables. The analysis begins with standard statistical techniques and continues with multiple regression and machine learning methods for non-linear regression, such as random forests. Both geographical and temporal patterns have been investigated. This study shows that some parameters have a weak linear correlation, while a statistically significant non-linear relationship occurs between them. It can be concluded that the GCR-climate connection does exist, and these non-linear relations should be investigated further, specifically in certain regions of the World.
Türkiye'de bulunan organize sanayi bölgelerinde termal güneş enerjisi uygulanmasina yönelik olanaklar ve engeller
Establishing alternative energy sources is one of Turkey's main goals, as stated by the Eleventh Development Plan (2019-2023). Therefore, understanding the possibility of applying such options is a need in the field. The thesis focuses on identifying the non-technical barriers and solar heat opportunities for industrial processes (SHIP) in Turkish industrial parks (IP). The thesis is expressly framed to support the definition of a European Common Research and Innovation Agenda (ECRIA) on SHIP as part of the European Horizon 2020 project Integrating National Research Agendas on Solar Heat for Industrial Processes (INSHIP). Firstly, the renewable energy (RE) technology potentials and the RE political and regulatory framework of Turkey is summarised. After setting the background, the research continues with two methods of field research in the Kayseri IP. By looking at the current prosumer models, driving, and the barriers to adopting SHIP technologies are examined. These factors feed into a discussion on what is required for prosumer models to increase and be sustainable in the long term. Therefore, they aim to generate a more robust policy discussion on future prosumer models for SHIP technology. The objective is to use the prosumer expertise in developing, producing, and applying SHIP technologies to drive growth in Turkey's renewable energy capacities and markets, and be a major supplier for these domestic and export SHIP markets. In the existing situation, the most popular project is PV rooftop systems with Feed-in-tariff (FiT) for prosumer in the IP. The thesis results show that the lead investor created a virtuous cycle and synergy, whereby word-of-mouth marketing by existing investors can complement and amplify the governmental investment promotion activity. According to the collected data set, incentives and financial support are top drivers for industries' self-production and consumption choice. Industries are interested in solar thermal energy for their heating and cooling demand. They have a desire to be energy self-sufficient and have a secure energy supply. However, the identified barriers, such as lack of clear policy and regulatory framework, lack of awareness about SHIP technologies, inhibit the deployment of solar thermal usage in the IP. To sum up, the outcomes indicate that the potential of SHIP exists and requires enterprises willing to take a step forward and move into a potentially innovative industry. By taking into account barriers and opportunities, there is an opportunity for the government to promote the growth of industrial prosumers and deployment of SHIP technology. On the whole, solar thermal offers a win-win approach for companies and also governments to boost their industry and at the same time contributing to both decarbonisation of the energy sector and sustainable development by bringing clean energy sources into their power supply while meeting heating and cooling needs.
Yenilenebilir enerji sektörü ve gönüllü karbon projelerinden Türkiye'nin yıllık denkleştirme hacminin incelenmesi
Turkey has a unique circumstance listed as an Annex I country of the United Nations Framework Convention and not listed as an Annex B country of the Kyoto Protocol. Due to this unique position, Turkey cannot benefit from flexible mechanisms and participated in the voluntary carbon market. Turkey has started to find alternative ways to reduce its GHG emissions cost-effectively. In this study, Turkey's annual offset volume is studied with five main cases based on Turkey's renewable energy sector, all Turkish voluntary carbon projects, Turkish voluntary carbon projects eligible to issue carbon credits, and issued and transacted Turkish carbon credits with a bottom-up approach. First, it is found that the annual offset volume from the renewable energy sector for 2018 was more than 52 million tCO2. Secondly, it is found that there are 436 Turkish voluntary carbon projects with a total annual offset volume equal to 33 million tCO2. Furthermore, it is realized that only 187 of them are eligible to issue carbon credits equal to an annual offset volume of more than 14 million tCO2. Lastly, it is calculated that the annual average issuance and transaction volume are respectively 3.6 and 2 million tCO2 for the period between 2010-2019. The results show that more than half of the annual offset volume is unavailable due to the ineligible projects. The actual market volume is even less considering the issuance and transactions. It indicates a need to increase the demand for the credits by introducing a mandatory offsetting requirement.
Üniversite kafeteryasında yemek atıklarına ilişkin bireysel davranışların ve ahlaki yargıların incelenmesi
Along with the global food crisis, climate change, population growth, urbanization, enlarging middle class, and shifts in consumption patterns, food waste became a severe problem to tackle. Around one-third of produced food, which approximates to 1.3 billion tonnes per year, has been globally wasted throughout the food supply chain. A considerable literature has proliferated around the theme of food waste; and yet the drivers of consumer-level food waste in emerging economies remains unattended. This dissertation aims to understand why and how students produce plate leftovers in the university cafeteria and justify their food wasting practices by applying two approaches. First, apart from the traditional variables of the Theory of Planned Behavior framework, it tests the effects of perceived portion size, taste and palatability, perceived value for money, and self-reported environmental behavior on students' behavior of leaving plate waste by surveying 479 students in the METU Cafeteria. Confirmatory Factor Analysis and Structural Equation Modeling results revealed that all factors, except attitudes and subjective norms, significantly affected the students' behavior regarding food waste in the university cafeteria. Moreover, a follow-up study is conducted to understand students' food wasting practice and justifications by interviewing 15 students. At this stage, Boltanski and Thévenot's Economies of Worth framework is adopted to uncover the moral complexity of wasting food practices. Findings elucidate that the students employed various moral regimes to justify their food wasting practice and developed strategies to eliminate food waste. Overall, the present research contributes to understanding the complex issue of wasting food in the METU Cafeteria from two different theoretical and methodological perspectives.
İklim değişikliği Türkiye'deki koruma alanları ağını nasıl etkileyecek?
Climate Change is a critical problem which might have irrecoverable effects on nature. Due to rising GHG concentrations in the atmosphere, and consequent global warming, global biodiversity is increasingly under threat. Protected areas are the most important tools to conserve biodiversity from destruction. That is why estimating future climatic conditions in protected areas plays a critical role in the prediction of possible changes in biota and ecosystems. Climate velocity is one such measurement that estimates the spatial change in climate over a certain period, which in turn can be used to assess how species or ecosystems will respond to climate change. Turkey will also be affected from climate change in this century. Therefore, to find out whether our protected area network will continue to be sufficient in in the future, and if movement of the biota inside towards newly climatically suitable areas will be possible, we will build a climate velocity surface for Turkey, estimate the positions of protected areas in the new climate space, and then assess whether they will be able to maintain their functions.
Bir yeşil altyapı bileşeni olarak yeşil çatı ve Türkiye'deki uygulamalar için çıkarımlar
With the transformation of natural areas into impermeable surfaces such as roads and buildings, the effects of climate change have been observed more frequently in the last decades. Some examples are natural disasters such as extreme heat waves, floods and forest fires that have been observed worldwide. The concept of "green infrastructure", which is defined as a network of natural and semi-natural areas, provides the maintenance of these areas, and offers their benefits to people. Green infrastructure creates a livable environment by protecting ecosystems and maintaining biodiversity with its multi-functionality, connectivity and multi-scale features. Green roof is considered as a green infrastructure element. This study analyzes the concept of green roof, the benefits it provides, illustrates different practical cases across the world, and evaluates how green roof can effectively be incorporated to the green infrastructure, with regard to the approaches and principles implemented in different cases. Lastly, the study describes some practices in Turkey, and seeks some urban policy implications for more effective implementations.
Emisyon azaltımı veya yerel fosil kullanımı:iklim değişikliği ile mücadelede yerel kömür kullanımı anlamlı mı
Energy policy of a country today deals with provision of secure, cheap and clean energy. Among the three, secure and cheap energy has general dominance over clean energy. Countries shape their energy policies accordingly and Turkey is no different example. Strategy Plan 2015 – 2019 of Ministry of Energy and Natural Resources emphasizes exploitation of domestic coal for energy security while Turkey intends to curb her emissions by 21% until 2030. These two targets contradict in terms of climate change mitigation. Therefore, Turkey has to establish a consistent policy that secures energy but, at least, does not exacerbate greenhouse gas emissions. This study aims to seek the role of coal, wind and solar power in such an energy policy making through panel econometrics and scenario analyses. Panel data estimates reveal that coal does not contribute to global energy security. Scenario analyses show that Turkey's use of domestic coal is vital but at the expense of climate change mitigation. On the other hand, both wind and solar contribute to country's efforts in energy security and climate change mitigation.
Optimum bidding strategy for wind and solar power plants in day-ahead electricity market
Yenilenebilir enerji kaynaklarından elektrik üretilmesine ilişkin olarak ana zorluk yenilebilir enerji kaynaklarının üretimlerinin stokastik bir yapıya sahip olmasından kaynaklı olarak kesintili olmasıdır. Bu durum gün içi piyasalarında dengesizlik maliyetlerine sebebiyet vermekte ve üretivciler arasında işbirliği imkanlarını gündeme getirmektedir. Dengesizlik maliyetleri söz konusu olduğunda, rüzgar güç santralleri ve güneş güç santrallerinin gün öncesi piyasasında gelirlerini arttırabilmeleri için 2 farklı strateji mümkündür: dengeleme grupları oluşturulması suretiyle ortak teklif verilmesi ve depolama teknolojilerinden faydalanılması. Literatürde işbirliğine dayalı ortak teklif verilmesi stratejisi ile depolama teknolojileri kullanılması stratejilerinin karşılaştırmalı olarak analiz edildiği çalışmalar son derece kısıtlıdır. Dengeleme sorumluluğu altında, sözkonusu stratejilerin karşılaştırmalı analizi bu çalışmanın literature ana katkılarından birisidir. Diğer katkı ise düzenleyici kurum tarafından uygulamaya konulan farklı düzenleyici yaklaşımların toplam gelire olan etkisinin ortaya konmasıdır. Farklı işbirliği gruplarını kapsayacak şekilde geliştirilen ortak teklif modeli, ilk stratejinin analizi için; depolama teknolojilerinin kullanımını kapsayan batarya kullanım modeli ise ikinci stratejinin analizi için geliştirilmiştir. Her bir stratejinin gelire olan etkisi analiz edilmiştir. Modellerin sonuçları analiz edildiğinde düzenleyici yaklaşıma duyarlı olan ilk stratejinin işbirliği gruplarının toplam gelirlerine %0.65 oranına ulaşan oranlarda artış sağladığı, ikinci stratejinin ise finansal olarak uygulanabilir olmadığı görülmüştür. Diğer taraftan, her bir MW batarya kullanımının güneş santrali için 400 dolar/MW-yıl gelir sağladığı, 15 adet rüzgar güç santrali için bu ilave gelirin 2,460 ile 6,795 dolar/MW-yıl aralığında olduğu görülmüştür. Dolayısıyla, bataryanın rüzgar güç santraleri için kullanımı güneş santrallerine göre 10 kattan daha fazla ilave gelir imkanı yaratmaktadır. İkinci stratejinin uygulanabilir olması için seviyelendirilmiş batarya maliyetlerinin, bahsi geçen ilave gelirlerin altına inmesi gerekmektedir.