Large-ensemble climate simulations to assess changes in snow stability over northern Japan

Abstract To examine the influence of global warming including increased heavy snowfall frequency on the potential of natural dry snow avalanche frequency and magnitude, we estimated the frequency of weak layer formation and the associated slab overload above the weak layer over northern Japan. The e...

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Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Katsuyama, Yuta, Katsushima, Takafumi, Takeuchi, Yukari
Other Authors: Forestry and Forest Products Research Institute, Japan Society for the Promotion of Science
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2022
Subjects:
Online Access:http://dx.doi.org/10.1017/jog.2022.85
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143022000855
Description
Summary:Abstract To examine the influence of global warming including increased heavy snowfall frequency on the potential of natural dry snow avalanche frequency and magnitude, we estimated the frequency of weak layer formation and the associated slab overload above the weak layer over northern Japan. The estimation was numerically performed using climate models' output for 1800 winter simulations in each of the historical (1951–2010) and +4°C experiments by forcing a physical-based snowpack model with the result of the climate models. Here the +4°C experiment was defined as a climate when the global mean air temperature had increased by 4°C from the preindustrial level. The estimation results showed that the probability of weak layer formation, identified by the natural stability index, would decrease all over the area because of the shorter age of the weak layers caused by a warmer climate, indirectly indicating a potential decrease in avalanche frequency. However, because of increased heavy snowfall frequency, slab overload would increase by 10–15% in inland areas for weak layers of decomposing fragments/precipitation particles and the mountainous area facing the Sea of Japan for weak layers of facets/depth hoar, thereby potentially indicating an increased magnitude of avalanches.