Yeşil alanların soğutma etkileri: İstanbul Anadolu yakası örneği
Cooling effect of green parks- Istanbul Anatolian side example
Yazar: AYŞE CANSU TURAN
Danışman: PROF. DR. AYŞE GÜL TANIK
İstanbul Teknik Üniversitesi / Lisansüstü Eğitim Enstitüsü / Bilişim Uygulamaları Ana Bilim Dalı / Coğrafi Bilgi Teknolojileri Bilim Dalı
Derece: Yüksek Lisans, 2023
Konu: Şehircilik ve Bölge Planlama = Urban and Regional Planning
Dizin: Peyzaj mimarlığı = Landscape architecture ; Soğutma = Cooling ; Yeşil alanlar = Green areas ; İstanbul = Istanbul ; İstanbul-Anadolu Yakası = İstanbul-Anatolian Side

Özet:
Sanayi devrimi ile birlikte hızla artan nüfus, plansız kentleşmeye yol açarak mevcut doğal alanları da etkilemiştir. Artan nüfus, ısıtma ve soğutma tüketimleri sonucunda şehirlerde araç kullanımının artması ve toprak yüzeylerin asfalt gibi malzemelerle kaplanması kentsel ölçekte sıcaklık farklılıklarına neden olmaktadır. Kentsel yeşil alanlar (KYA), iklim değişikliği ile doğrudan ilgili olan kentsel ısı adalarının etkisini azaltmada serinletici etkiye sahiptir. Bu çalışmanın amacı, yeşil alanların İstanbul Anadolu Yakası mikro iklimi üzerindeki soğutma etkisini değerlendirmektir. 2018 Landsat 8 OLI/TIRS uydu görüntüsü verileri incelenerek, Yer yüzey Sıcaklığı (YYS) ile parkların tampon mesafeleri arasındaki ilişki tespit edilmiştir. Geçirimsiz yüzeyleri tanımlamak için geçirimsiz yüzey yoğunluğu verileri kullanılır. 2018 yılında yapılı alanlar ile doğal alanlar arasındaki sıcaklık farkı tespit edilmiş olup, geçirimsiz yüzeyler ile doğal alanlar (geçirimli arazi) arasındaki sıcaklık farkının 5,4°C olduğu gözlemlenmiştir. YYS ölçeğinin net bir değerlendirmesi için 25.000 m²'nin üzerinde İstanbul ili Anadolu Yakasında 65 kentsel yeşil alan seçilmiş olup, bu parkların ortalama sıcaklığı 25.57°C olarak belirlenmiştir. Soğutma etkisini belirlemek için kullanılan 3 metrikten Soğutma yoğunluğu (CI), Soğutma Kapsamı (CE), Soğutma Süresi (CL) ortalama CI değeri 1,5°C ve maksimum değeri 7,8°C'dir. İstanbul'daki CI değeri mekansal olarak incelendiğinde, genellikle Boğaz'a yakın yeşil alanlarda arttığı görülmektedir. Park alanının büyüklüğü arttıkça YYS azalmaktadır. KYA'nin YYS'si ile su mesafesi arasında güçlü bir korelasyon vardır. Bu, gelecekte yeşil alanların sadece alan olarak büyümesinin değil, içinde ve çevresinde kullanımının da dikkatli bir şekilde planlanması gerektiğinin bir göstergesidir. Seçilen 4 adet parkta yapılan detaylı incelemelerde ise yeşil alanların çevresindeki AÖ/AK'nın soğutma etkisinin devamlılığını sağlamadaki önemli ortaya konmuştur. Özellikle yeşil alanlar koridor şeklinde tasarlandığında veya su alanları ile birlikte devamlılığı oluşturulduğunda soğutma etkisi artmaktadır. Çalışma ile peyzaj yapısındaki yeşil parkların ekolojik işleyişinin bilimsel bulgulara dayalı olarak daha iyi planlanması gerektiği sonucuna varılmıştır. Bu nedenle bu çalışma, İstanbul gibi sıcak ve nemli şehirlerde Kentsel Isı Adası (KIA) değerlerini azaltmak amacıyla yeşil alanların tasarlanmasında verimli soğutma etkilerinin öneminin altını çizmek için bir örnek oluşturmaktadır.

Abstract:
The rapidly increasing population with the industrial revolution led to unplanned urbanization and this situation also affected the existing natural areas. As a result of the increasing population, heating and cooling consumption, the increase in the use of vehicles in cities and the covering of soil surfaces with materials such as asphalt cause temperature differences at the city scale. Urban green spaces (UGS) have a cooling effect in reducing the impact of urban heat islands, which are directly related to climate change. The province of Istanbul has also become a center of attraction due to its socio-economic resources, and therefore its population has increased rapidly. The increase in the city caused unplanned construction and the emergence of high-rise buildings. Thanks to the detailed researches in this study, it is seen that there are not enough resources in the literature on the ecological balance and cooling effect of urban green spaces in Istanbul. In the study, the identity gained to urban green areas; It is related to Health and Quality Life (No: 3), Sustainable Cities and Communities (No: 11), Climate Action (No: 13) and Terrestrial Life (No: 15), which are among the Sustainable Development Goals, and serve 4 of 17 purposes. also aims to In this context, the study is a scientific research. With the correct planning of green areas, the "Health and Quality of Life" clause is aimed at "to significantly reduce the number of diseases and deaths caused by harmful chemicals and air, water and soil pollution by 2030", and the "Sustainable Cities and Communities" clause "by 2030" Reducing the negative environmental impacts of cities per capita by paying special attention to air quality and municipal waste management and other waste management, all the items in the "climate action" plan, and the "terrestrial life item" to "desertification, protection of ecosystems, impacts on terrestrial ecosystems". will directly serve the issues of "reduction". The increase in built up areas over the years has led to a decrease in green areas. This has had an impact on the cooling effect of urban green spaces. For this reason, the aim of this study is to evaluate the cooling effect of green areas on the microclimate by focusing on 4 parks located on the Anatolian Side of Istanbul-Turkey, on a micro scale. The biggest reason for choosing the Anatolian side is the evaluation of the effect of the increasing construction on green areas after the urban transformation works. In the study, primarily the change of urban green areas between the years 2012-2018-2021 in the whole of Istanbul is examined, then the effect of construction is evaluated by revealing the temperature difference between natural areas and artificial areas in the Anatolian side. Between 2012-2021, the impervious surface of Istanbul increased by 13,324 ha. While the impervious surface increase rate is 10% between 2012-2018, it is 4% between 2018-2021. The total rate of change between 2012 and 2021 is 11%. Especially between these years, it is seen that transportation investments have increased in the peripheries of the city. In order to evaluate the micro-scale effects of the park areas and to examine the surrounding land uses, the buffer zones of 4 selected parks and the structures entering these areas and which are thought to affect the LST, areas such as streets and parks are shown. The UGS is chosen from seaside, streamside and densely populated areas in order to diversify the uses around them. These are Hacıbaba Park, Moda Beach Park, Liberty Park and Mimar Sinan Park. Then, the CI, CE, CL and landscape metrics of urban green areas over 25,000 m2 on the Anatolian sidexamined. Thus, the internal and external dynamics of green areas have been revealed. In order to evaluate the micro-scale effects of the park areas and to examine the surrounding land uses, the buffer zones of 4 selected parks and the structures, streets and parks, which enter these areas and are thought to affect the LST, are shown. The UGS is chosen from seaside, streamside and densely populated areas in order to diversify the uses around them. These are Hacıbaba Park, Moda Sahil Park, Özgürlük Park and Mimar Sinan Park. In other studies, 2018 data is used. This is due to the fact that the most usable satellite image (cloudiness, etc.) is obtained in 2018. 2018 Landsat 8 OLI/TIRS satellite image data is analyzed to determine the relationship between the land surface temperature (LST) and the buffer distances of the parks. Impervious surface density data is used to identify impervious surfaces. In 2018, the temperature difference between built-up areas and natural areas are determined, and it is seen that the temperature difference between impervious surfaces and natural areas (permeable land) is 5.4°C. According to the 2018 LST data, the coldest points of the Anatolian Side are located in forest areas and seaside, while the hottest points are located in Ümraniye, Sancaktepe, Sultanbeyli, Ataşehir and Tuzla district, where industrial areas are densely populated. As a result of the study, the average LST value of the green areas in 65 parks are calculated as 25.57°C. While the minimum LST value is 16.1°C, the maximum LST value is 31.2°C. The average CI value of the 3 metrics used to determine the cooling effect is 1.6°C, while the maximum value is 7.8°C. The average value of CE is 120 m, while its maximum value is 300 m. The average value of CL is 11.2°C/km and the maximum value is 54.4°C/km. The LST value of the park areas close to the water resources is lower than the others. For a clear assessment of the LST scale, 65 urban green areas over 25,000 m² is selected on the Anatolian Side of Istanbul and the average temperature of these parks are found to be 25.57°C. Of the 3 metrics used to determine the cooling effect (Cooling Intencity (CI), Cooling Extent (CE), Cooling Lapse (CL)) the average CI value is 1.6°C and the maximum value is 7.8°C. When the CI value in Istanbul is analyzed spatially, it is seen that it generally increases in green areas close to the Bosphorus. The LST decreases as the UGS area grows. There is a strong correlation between the LST of the UGS and the Water Distance. Especially the 4 selected parks show that the LC/LU cooling effect on the periphery of the urban green areas is extremely effective in spreading the cooling effect into the city. The proximity to the water and the density of buildings around it is taken into account in the selection of the park areas, and the findings show that the CI value and CE value of the green areas close to the water resources are much higher than the others. This is an indication that in the future, the use of green areas as an area, as well as their use in and around, should be carefully planned. It has been concluded that the ecological functioning of green parks in the landscape structure should be better planned based on scientific findings. UGS areas in the province of Istanbul; It should be designed in a way that will spread the cooling effect coming from the sea into the city with urban green spaces and valley beds (green corridors and networks). Climate-based urban plans/development models should be put forward urgently in order to prevent urban green spaces from being planned only to meet the equipment standards in zoning plans and to prevent Istanbul from being exposed to irreversible adverse conditions. The ecological effects of each decision taken should be kept under control. Urban transformation projects, transportation and infrastructure projects, urban development areas, urban agriculture projects should be adopted as an opportunity to create urban green areas. Plans should be planned in a holistic way by adopting a green city vision, not in a piecemeal way.