The current state and future of continentality/oceanity at Turkey

This study aims to examine the potential impacts of future changes under climate change scenarios by analyzing Turkey's continentality and maritime characteristics. In the study, the current (1981-2010) and future (2011-2100) continental/maritime patterns of Turkey are evaluated using major indices such as Conrad, Johansson, Kerner and Sezer. Conrad continentality index is one of the most widely used indices in the literature. Although it is similar to the Johansson index, the Johansson index deals with temperature parameters in a more comprehensive manner. Unlike the other selected indices, the Kerner oceanility index measures oceanility, not continentality. It was tried to determine what kind of differences would arise in the results of the study by choosing a formula that measures oceanility in addition to the degrees of continentality. The Sezer formula is a formula developed specifically for Turkey, contains more parameters compared to other formulas, and is thought to give more accurate results for our country. The findings of the study reveal that most of Turkey has a continental climate, while coastal areas are characterized by maritime influences. According to the Kerner oceanility index, 68.3% of Turkey was classified as continental, 29.4% as subcontinental and 2.2% as oceanic in the 1981-2010 period. This indicates that the continental regions of Turkey are dominated by distinct continental climate characteristics. The limited maritime areas reflect the reduced maritime influence and wider temperature fluctuations in the interior of Turkey. According to the Conrad index, extreme continental areas covered 0.3% of Turkey in the 1981-2010 period, increasing to 22.9% in the 2071-2100 period according to the worst-case scenario. According to the Johansson index, extreme land areas are the same (66.8%) in the 1981-2010 and 2011-2040 period under the worst case scenario, but extreme land areas are 87.2% in the 2071-2100 period under the worst case scenario. Future projections, especially under the SSP5-8.5 (worst case) scenario, show that terrestrial areas will expand and marine areas will shrink. This can be explained by the fact that the stabilizing effect of the season temperature and humidity decreases with the impact of climate change and continental climate characteristics become more pronounced. For example, according to Sezer's formula, 0.8% of Turkey was classified as oceanic-maritime, 4.6% as oceanic-maritime/terrestrial transition, 79.6% as continental, and 14.8% as severe cold continental climate in the period 1981-2010. The findings of the study indicate that future changes in continentality and oceanility could have significant impacts on Turkey's ecosystems, water resources, agricultural productivity and natural disaster preparedness. Increasing continental climate characteristics in inland areas may have negative impacts on agricultural productivity and water resources in these regions. For example, according to the SSP1-2.6 scenario, 0.7% of Turkey is classified as oceanic-maritime climate, 4% as oceanic-maritime/continental transition climate, 78.7% as continental climate and 16.4% as severe cold continental climate for the period 2011-2040. In conclusion, this study reveals that Turkey's continental and oceanic characteristics will show significant changes in the future and that these changes provide valuable information in terms of measures and strategies to be taken against climate change. The findings of the study provide important information for policy makers in areas such as water resources management, agricultural planning and natural disaster preparedness.