## 6 Difference between Laboratory and Nature Environment and Ideal Assumptions of the Model  
Artificial freeze-thaw weathering tests in a laboratory may produce different degrees of weathering than natural freeze-thaw weathering due to factors such as saturation of rock pore water and the size of the specimens. Because the rocks in the study area are exposed to extreme temperature conditions and are close to the coast, compared to the freeze-thaw test, they will be influenced more by salt crystallization weathering due to the air temperature, wind and seawater. Due to these complex factors, it is very difficult to elucidate the relationship between freeze-thaw weathering in the laboratory and the nature environment. Assuming that the rock durability parameters including strength and stiffness of artificial weathering and natural weathering are similar under reasonable application of temperature variation; the extent of rock weathering in the laboratory freeze-thaw test can be also assumed to be closely related to the number of freeze-thaw cycles in nature. In cool and temperate climate regions at high latitudes, frequent freezing and thawing during the year can be the greatest cause of rock weathering [24]. The rock damage caused by freeze-thaw, in both damaged and undamaged rocks, mostly consists of granular disintegration and flaking as a result of mechanical stress leading to micro fissures [83,84]. The typical damage process begins with volumetric expansion or ice separation caused by the meteorological environment. Generally, the inside of the rocks can become weakened by a single freeze-thaw cycle, but several cycles are required before signs of weathering or damage become visible [85]. This freeze-thaw damage is used to estimate the likelihood of freeze-thaw structural damage to buildings and civil super structures founded on rocks. As shown in part one [27] of two companion papers, when the daily mean temperature was analyzed in the study area throughout the year, the authors found that freeze-thaw could occur at the rock surface tens (33-62 cycles) of times per year. These changes were mostly freeze-thaw in seasonally frozen ground, and rocks exposed to the surface underwent more freeze-thaw than rocks buried in the ground. Future changes in the extent of weathering can be examined by looking at changes in the weather, based on the same logic as using past weather data to estimate the number of freeze-thaw cycles for previous weathering [18]. The general decrease in freeze-thaw cycles in northern regions could be due to the effects of rising temperatures in Europe since the 18 th century, but there could also be changes in the number of freeze-thaw cycles due to increased urban heat island effects, which are especially important for buildings [11]. The predicted rise in global temperature during the current century means that freezing will decrease in most European regions, and diminished physical properties of rocks due to freeze-thaw will be less likely. Nevertheless, increased air temperatures in the Arctic Circle could lead to structural loss and collapse due to its effects on archaeological heritage sites preserved in the permafrost layer. Freeze-thaw cycles can cause landslides due to their effects on the foundations of structures. In addition, the frequency of freeze-thaw cycles for cultural heritage and the duration of changes in weathering can support administrators' strategic decision-making regarding maintenance, repair and prevention of collapse of cultural heritage. When freeze-thaw of the rock surface was analyzed using changes in daily minimum and maximum temperatures for 5 consecutive years in the study area, the minimum and maximum air temperature were found to change from below to above zero on 33-62 times per year. When estimating freeze-thaw of the rock surface, the authors assumed that natural freeze-thaw will have occurredsimilar to 33-62 times per year at the rock surface and at a depth of 25 mm, which was the maximum depth of the rocks tested in this study.