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ÖgeDetermination Of Last Glacial Equilibrium Line Altitudes Of Turkey By Glacial Mass Balance Model(Eurasia Institute of Earth Sciences, 2018-06-28) Gündüz, Savaş ; Sarıkaya, Mehmet Akif ; 602161006 ; Solid Earth Sciences ; Katı Yer Bilimleri Anabilim DalıTurkey is located in the Eastern part of Mediterranean region between 36°N and 42°N latitude and 26°E and 45°E longitude. Turkey's climatic and topographic features have strong contrasts which indicate a characteristic feature for Turkey. As a general view, Turkey has a varied topography for its all geographical regions. Turkey is a mid-latitude country located with a relatively high topography. In the current climate of Turkey, glaciers do not occupy large areas but it is known that paleo-glaciers covered larger areas during the Last Glacial stage based on earlier studies. There is a close relationship between climate and equilibrium line altitude (ELA) of a glacier. Glaciers are the most commonly used indicators for climate change. The purpose of this study is to calculate Turkey's ELA by glacial mass balance model during the Last Glacial Maximum (LGM) and compare with previous studies. For this purpose, monthly present day temperature and precipitation were used to make paleo-climatic estimations. The Last Glacial stage ELA were determined by a glacier mass balance model and compared with previous studies. In total, 25 glacial areas have been studied. Using the monthly temperature and precipitation data obtained from WorldClim, annual ablation was calculated by positive degree day model and annual accumulation were calculated assuming that precipitation falls as snow at 0°C. Calculations made by an in-house Matlab program. Annual mass balances were found with the difference between the accumulation and ablation values. The simulations for the last glacial period were firstly done with the precipitation was kept the same as the present conditions, and the temperature depressions was changed between -8°C and -12°C. In the second case, the temperature was kept constant (-10°C lower than today), the precipitation was changed from drier (%25 drier) to humid (%25 wetter) conditions than today. Accordingly, the last glacial paleo-equilibrium line altitudes in Turkey were calculated and spatially compared with earlier studies. When temperature is 10°C cooler than today and precipitation is in the present day condition (Precipitation=1), ELA decreasing from south of Turkey to the north. It is almost between 2400- 2500 m a.s.l. in the Southeast Taurus. In Akdağ and Beydağ, ELA is more than 2200 m a.s.l in Sandıras, Davraz, Dedegöl, Geyikdağ, Aladağlar and Bolkar, ELA is about 2200 m. It has a decreasing pattern toward to north. Erciyes and Soğanlı Mountains have ELA 2000-2200 m. In Uludağ which is situated in the north part of the Turkey it is in between 1600-1800 m. In the eastern part of Turkey, ELA is higher when it compared with western Turkey. In Buzul and İkiyaka Mountains, ELA is in between 2600-2700 m. Southeast part of Turkey has the highest ELA value. For –10°C temperature decrease and same as today's precipitation values (from south to north) there is a decreasing pattern. It shows that there is clear latitude effect in Turkey's ELA. From west to east ELA is increasing as elevation 'increasing from west to east. It also shows that elevation affects the ELA in Turkey because elevation is increasing from west to east. The places where elevation is high have higher ELA compared to other places in the Turkey. According to the study of Messerli (1967), ELA is 2300 m in the Black Sea region. When the temperature -8 °C below today and present day precipitation condition, ELA estimates of 2000- 2100 m in the Black Sea close the Messerli's estimates. In the Mediterranean ELA is around 2500 m. For Mediterranean, all results that I have are higher than 2000 m. This can indicate ELA is almost same values in the Mediterranean in LGM. In the south east region that have most of the glaciers, ELA is between 2700-2800 m in the study of Messerli (1967). It is more than 2400-2500 m in southeast region for all the cases applied. That also shows that there is a match between these values. In the west part of Turkey, ELA is around 2300 m in Messerli (1967) study but in this part, I got lower ELA values when it compares to Messerli (1967)'s study.