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About 10% of Europe's surface area is prone to rapid flooding of rivers confined in valleys. The devastating potential of such floods is exacerbated by the deficits of existing gauging networks, including low station densities and recording frequencies, and lack of information beyond stage height. Here, we use seismic data of the July 2021 Ahrtal flood, Germany, to extract information to complement sparse hydrometric data, and to reconstruct the rapid evolution of this fatal event. We show that a seismic station can deliver essential flood metrics such as magnitude, propagation velocity and debris transport rate. These seismic products provide high resolution insight to the non‐linear flood behavior. We argue that an approach combining distributed low‐cost seismometers with existing seismic stations, can provide important real time data on future catastrophic floods and associated hazards in upland catchments, offering precious response time also in currently ungauged landscapes. Plain Language Summary: Rapidly evolving floods are a major hazard for 10% of European landscapes. They are hard to adequately detect and describe by the classic gauge station scheme, but seismic sensors provide a valuable alternative to this difficulty. A seismometer can sense a flood like the devastating one that hit the Ahr valley, Germany, in July 2021 up to 1.5 km away. The seismic footprint of the flood allows to provide information on flood magnitude, velocity and trajectory at sub‐minute resolution and at near real time. We show how this new approach can be utilized for future flood protection. Key Points: Seismic sensing of valley confined floods improves classic detection approachesNear‐real time information on flood magnitude, trajectory, and velocityGate keeper seismometer networks can improve flood risk management in Europe [ABSTRACT FROM AUTHOR]

Subsurface monitoring of permafrost conditions at depths up to 20-30 m is crucial to assess the safety and reliability of mountain infrastructure, because permafrost degradation critically affects rock slope stability in high mountains. Electrical resistivity tomography (ERT) provides a straightforward tool for monitoring near-surface bedrock permafrost at monthly or longer intervals. But as rockfalls are often prepared over periods of hours or days, ERT for early warning purposes should also detect short-term triggering events such as pressurised water flow. Here, we present the first approach to monitor steep permafrost rock walls quasi-continuously with ERT. We measured ERT every 4 h at the up to 67° steep rock wall below the Kitzsteinhorn cable car, Austria. Wenner datasets (n = 996) were analysed from February 2013 to February 2014 in terms of data stability, raw data characteristics and measurement errors coinciding with potential disturbing factors. Strong resistivity changes coincided with rapid freezing or water inundating rock fractures. Automatically detected periods with large resistivity changes produce ERT time series with low resistivities extending from the bottom upwards during times of snowmelt. We infer that flow of pressurised water in fractures warms the surrounding rock in an upward direction, based on fracture inventories, visual observations of cleftwater and near-surface temperature measurements. We develop a strategy for ERT monitoring suitable for potential early warning systems, where high apparent resistivity changes in 4 h intervals may precede critical hydrostatic events confined by permafrost rocks. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the occurrence, movement, and contribution of ground water in Loch Vale in the Front Range of the Colorado Rocky Mountains in Colorado. It states that hydrogeomorphologic mapping, seismic refraction measurements, and porosity and permeability estimates were made, indicating that talus slopes were the primary ground water reservoir. The result of the study confirm the role of talus ground water in streamflow during storm and winter base-flow period.