Frost heave in Mexican high-mountain landscape: A theoretical approach to understanding needle ice formation in periglacial environments of tropical high lands

Although studies related to periglacial dynamics in Mexico have advanced in recent years, there are still gaps in knowledge that need to be addressed to explain the various mechanisms associated with slope dynamics, which commonly occur recurrently in the high mountains of Mexico. Using both theoretical and empirical approaches, through the construction of indices of acicular ice formation potential, based on air and surface temperatures, atmospheric humidity levels, and wind speed, complemented by direct visual field observations, this study analyzes the formation of needle ice and the frost heave it causes in the upper part of the Cofre de Perote volcano. The aim is to understand how this repetitive process over time may prevent the consolidation of granular volcanic soils exposed to solifluction. The results indicate that the formation of needle ice takes place during the colder months of the year, because of the combined effects of air humidity, temperature, and wind speed, which together can give rise to ice needles ranging from a few millimeters to more than 7 cm in length. From a geomorphological perspective, the repetitive process of frost heave may be one of the factors explaining why granular soils in periglacial environments remain loose and exposed to various erosional dynamics, including fluvial, aeolian, and gravitational processes. From a climatological standpoint, the recurrent formation of acicular ice makes it possible to observe some of the effects of daily freeze–thaw cycles at the surface, which are closely associated with the gelifraction of bedrock and rock walls in the high mountains of Mexico. This study contributes to the understanding of high-mountain climatology, particularly by addressing a phenomenon that remains poorly understood within the scientific literature on tropical high-mountain environments.