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Permafrost Long-term Monitoring Network (PermaNET) - Contribution UZH

Das Projekt "Permafrost Long-term Monitoring Network (PermaNET) - Contribution UZH" wird vom Umweltbundesamt gefördert und von Universität Zürich, Geographisches Institut durchgeführt. The PermanNET project aims at establishing an Alpine-wide permafrost monitoring network, a permafrost map for the entire Alpine region, and a common strategy with guidelines for the consideration of permafrost in risk and water resource management. PermaNET is a transnational cooperation (Austria, France, Germany, Italy, and Switzerland) and is part of the European Territorial Cooperation Alpine Space Programme 2007-2013. In the scope of this projects, the University of Zurich works together with the Federal Office for the Environment (FOEN), the Bavarian Environment Agency (LfU Bayern), Germany, and the Central Institute for Meteorology and Geodynamics in Salzburg, Austria. In addition, the University is an official Observer to the Project Steering Committee.

PERMOS: Swiss Permafrost Monitoring Network

Das Projekt "PERMOS: Swiss Permafrost Monitoring Network" wird vom Umweltbundesamt gefördert und von Universität Zürich, Geographisches Institut durchgeführt. The Swiss network for permafrost monitoring documents the status and long-term variations of permafrost in the Swiss Alps. Borehole measurements together with ground temperature measurements in the area of the drill sites build the basis of the monitoring network. They are complemented by systematic observations of permafrost geomorphodynamics, which allows for an integral assessment of the permafrost state in the Swiss Alps. PERMOS is coordinated by the PERMOS Office and supervised by the Cryospheric Commission (CC) of the Swiss Academy of Sciences (SCNAT). The measurements and site maintencance are undertaken by several partner institutions from academia. Within the international framework of permafrost monitoring and research, PERMOS is one of the components of the Global Terrestrial Network for Permafrost (GTN-P) that is currently being established within the worldwide climate-monitoring program(GCOS/GTOS) of the World Meteorological Organization (WMO) and others (FAO, UNEP, UNESCO, ICSI). In Switzerland, PERMOS complements the Swiss Glacier Monitoring Network.

TEMPS-B: Ground ice and water content estimation and integrative analysis of mountain permafrost monitoring elements

Das Projekt "TEMPS-B: Ground ice and water content estimation and integrative analysis of mountain permafrost monitoring elements" wird vom Umweltbundesamt gefördert und von Universität Zürich, Geographisches Institut durchgeführt. Subproject B of the SNF-sinergia project TEMPS 'The Evolution of Mountain Permafrost in Switzerland' aims at a process-oriented understanding of the landform-specific sensitivity of mountain permafrost (bedrock terrain, talus slopes, rock glaciers and ice-cored moraines) to climate anomalies by performing a joint analysis of a comprehensive set of surface and subsur- face temperature, geophysical, meteorological and kinematic monitoring data from already established permafrost sites in the Swiss Alps. The project will focus on gaining a better understanding of the landform-specific dominant fac- tors responsible for changes in ice and water contents. Based on geophysical surveys and high-resolution geophysical monitoring, it is planned to systematically determine (i) the 4-phase (rock/air/ice/water) fractional composition of the ground on different landforms, (ii) their temporal changes, and (iii) their relation to changes of thermal and meteorological parameters at the same sites. A particular focus will be on analyzing the relation between the temporal changes in geophysi- cal properties of the subsurface to concurrent changes in the movement rates of rock gla- ciers to investigate the role of snow melt and groundwater for rock glacier movement.

Quantification of ice content in mountain permafrost based on geophysical data and simulated annealing

Das Projekt "Quantification of ice content in mountain permafrost based on geophysical data and simulated annealing" wird vom Umweltbundesamt gefördert und von University of Fribourg, Geosciences Departement, Geography Unit durchgeführt. Current and future global warming will cause the degradation of mountain permafrost, which may strongly influence the stability of permafrost slopes or rock walls with potentially hazardous consequences. Due to the strong heterogeneity of both the thermal regime and the ground composition of mountain permafrost, its response to atmospheric forcing can however be highly variable for different landforms and within short distances. The spatial distribution of ice and liquid water is important for determining the sensitivity of a specific permafrost occurrence to climate change because of their large influence on the pace of temperature changes (by effects of latent heat) and their importance for geotechnical properties of the ground. Detailed knowledge of the material properties and internal structures of frozen ground is therefore an important prerequisite to determine the sensitivity of permafrost to climate change. Except for the active layer ice and water contents and their temporal and spatial variability usually cannot be measured directly. Geophysical methods are sensitive for the ice and liquid water content in the ground. With the proposed collaboration, two similar but complementary approaches to quantify the composition of the ground based on 2D sections of geophysical data will be combined for an improved determination of ice and water contents in permafrost regions. The so-called 4-phase model (4PM) is based on two simple petrophysical relationships for electrical resistivity and seismic velocity and estimates volumetric fractions of ice, water, and air within the pore volume of a rock matrix by jointly using complementary data sets from electric and seismic measurements. Due to inherent ambiguities in the model it is still restricted to specific cases and often allows only a rough estimation of the phase fractions. Major drawbacks of the current 4PM comprise the unsatisfactory discrimination between rock and ice and its under-determinedness, requiring the prescription of the porosity and further parameters. The so-called RSANN model (developed and used by the host institution) uses the technique of simulated annealing (a Monte-Carlo-type stochastic simulation approach) as an optimization tool for the integration of electrical resistivity and P-wave velocity to derive 2D sections of porosity, water saturation and volumetric water content. The simulated annealing technique allows - due to its iterative procedure - more parameters to be predicted instead of being prescribed as in the 4PM. The objective of the proposed collaboration is to combine the advantages of the two algorithms (4PM and RSANN) to overcome the shortcomings of the 4PM in order to improve the reliability of the determined ice and liquid water contents. (...)

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