Student Research Reports

This study aims to compare cloud formation over mountainous and lowland areas in Mueang District, Chiang Mai Province, as well as to examine atmospheric factors that may influence such differences. Sky images above Doi Suthep and nearby lowland areas were recorded simultaneously four times per day over a continuous period from November 2024 to February 2025. Cloud cover was analyzed from the images using the ImageJ program, in conjunction with meteorological data analysis, including air temperature, relative humidity, and wind speed, obtained from weather station databases and Google Earth Engine. The results show that cloud formation over mountainous areas generally shows higher cloud cover than over lowland areas, especially on clear-sky days. This is likely due to the mechanism of orographic lifting, where air masses are forced to rise upon encountering mountainous terrain. However, during certain periods, cloud cover over lowland areas was found to be comparable to or greater than that over mountainous areas. This phenomenon is believed to result from increased relative humidity during cooler periods, as well as wind patterns that transport water vapor into lowland regions, facilitating cloud formation. In conclusion, topography and atmospheric conditions such as relative humidity, temperature, and wind are key factors influencing cloud formation. Keywords Mountain cloud formation, lowland cloud formation, weather conditions, cloud formation, topography