Fast long-term denudation rate of steep alpine headwalls inferred from cosmogenic 36Cl depth profiles

Radiography using cosmic-ray electromagnetic showers and its application in hydrology

In-situ measurements of soil water content provide important constraints on local/global hydrology. We demonstrate that the attenuation of the underground flux of cosmic-ray electromagnetic (EM) particles can be used to monitor the variation of soil water content after rainfalls. We developed a detection system that preferably selects EM particles by considering the coincidence of distant plastic scintillators. The calibration test beneath the water pool revealed that the count rate decreased by 0.6–0.7% with a 1 cm increase in the water level. The field measurement performed in the horizontal tunnel showed that the count rate dropped according to 48-h precipitation, after correcting the effects originating from atmospheric and water vapour pressures. These characteristics were confirmed using dedicated Monte Carlo simulations. This new method is called cosmic electromagnetic particle (CEMP) radiography.

Mountain surface processes and regulation

Mountains cover about a quarter of the world’s land surface, and directly support a significant proportion of the world’s population living within mountainous regions. Mountains provide water, timber and non-timber forest products, mineral resources, and many other food, fiber, and fuel products. Mountains also provide diverse ecosystems, in terms of both species and genetics, due to the topographic complexity in mountains increasing isolation and promoting speciation. Managing mountain regions for the sustainable delivery of critical goods and services requires an increasingly detailed understanding of mountain surface processes and regulation. The aim of this Guest Edited Collection is to provide a platform for interdisciplinary studies of mountain surface processes, and their responses to climate change and human activities.