In this study, climatological properties of fog types, their association with surrounding environment and background synoptic mechanisms triggering fog formation are investigated for Turkey. For this purpose, SYNOP (surface synoptic observations) and METAR (meteorological aerodrome report) codes of 105 stations are used for the period 2014–2019. While fog types are separated to the fog, quasi-fog, and dense fog events according to horizontal visibility conditions, stations are classified as mountain, seaside, urban, and rural by considering the surrounding environment. Synoptic mechanisms causing the occurrence of springtime marine fog events over Black Sea are investigated using NCEP/NCAR Reanalysis. According to the main results, highest numbers of fog events are observed during winter, spring, fall, and summer months, respectively. Radiation fog frequently occurs in the mountainous regions (i.e., central and eastern part) of Turkey during winter. As a result of the rainfall during daytime, significant amount of moisture begins to saturation at night owing to rapid cooling processes and fog layer forms just above the surface. During spring, Black Sea-effect marine fog events are frequently shown in the seaside stations of the Black Sea and northeastern Marmara regions. On the western Black Sea, winds from northeast enable rising of cold sea water to the surface (upwelling) and transfer it to the relatively warm land areas. Denser humid and cold air settling on the surface forces warm land air to rise. Additionally, warm air advection at 850 hPa (low level) creates a thick inversion layer over the region. For the eastern Black Sea, relatively cold and humid sea surface transferred to the coasts by light local northwesterly winds encounters with the mountain barrier and is trapped in the region. Furthermore, southerly winds (850 hPa) cross over the Kaçkar Mountains cause föehn effect and generate an inversion layer over the fog layer.

中文翻译：

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土耳其雾的气候学研究

在这项研究中，研究了土耳其雾类型的气候学特性、它们与周围环境的关联以及触发雾形成的背景天气机制。为此，在 2014-2019 年期间使用了 105 个站点的 SYNOP（地面天气观测）和 METAR（气象机场报告）代码。雾的类型根据水平能见度条件分为雾、类雾和浓雾事件，根据周围环境将站点分为山地、海边、城市和乡村。使用 NCEP/NCAR 再分析研究了导致黑海春季海雾事件发生的天气机制。根据主要结果，分别在冬季、春季、秋季和夏季观察到最多的雾事件。冬季，土耳其山区（即中部和东部）经常出现辐射雾。由于白天的降雨，大量的水分在夜间开始饱和，这是由于快速冷却过程和表面上方形成的雾层。春季，黑海海雾事件频繁出现在黑海和东北马尔马拉地区的海滨站。在黑海西部，来自东北的风使寒冷的海水上升到地表（上升流）并将其转移到相对温暖的陆地区域。更密集的潮湿和寒冷的空气沉降在地表，迫使温暖的陆地空气上升。此外，850 hPa（低层）的暖空气平流在该地区形成厚逆温层。对于黑海东部，相对寒冷和潮湿的海面被轻微的局部西北风转移到海岸，遇到山体障碍并被困在该地区。此外，越过 Kaçkar 山脉的南风 (850 hPa) 造成焚风效应，并在雾层上形成逆温层。