Geoelectrical monitoring

Instead of analysing the eleven individual resistivity tomograms between September 1999 and August 2000 in terms of absolute values, the cumulative resistivity differences per day based on the first September measurement are shown in Figure 6.7. Largest resistivity increases (white shading) were observed in October, when the snow cover was not yet established and cold temperatures could penetrate into the subsurface (Figure 6.7b). Freezing extends along the whole survey line and reaches a depth...

Precipitationrunoff models and sediment transport

In contrast to evapotranspiration models, precipitation-runoff models should describe both water and sediment dynamics in confined mountain valleys. Geomorphological zoning (Naef 2002) is especially important for precipitation-runoff models that comprise lateral flow on slopes and include the problem of sediment sources bed stability and coarse sediment transport. A prerequisite for defining surface runoff is the definition of the catchment boundary. In high alpine regions, catchment boundaries...

Carryover of system states

By the rules of fuzzy arithmetic presented in the Appendix, the magnitudes ofthe fuzziness ofthe modeled system state variables (snow water equivalent, SN, and soil moisture, S), computed using Equations (10.5) and (10.6) above, will continue to increase over time. For example, in the case of SN, more and more highly uncertain snow accumulation and depletion processes take place as winter progresses and leads to a continuous increase of fuzziness of SN. In late spring, with rising temperatures...

Dye tracer experiment

In this section, the observations from the dye tracer experiment at Hannigalp are summarized. The stained water flow paths observed in most of the excavated profiles showed a pronounced heterogeneous pattern. Distinct preferential flow fingers formed at the soil surface and led down to the somewhat coarser soil layer at 40-80 cm, just above the bedrock, where the water was able to spread. According to our observations, the hydrophobic soil surface, small ant channels and plant Winter 2000 01...

Modeling program

Water-balance simulations of the WRCCRF were made using the SHAW model. The SHAW model simulates a vertical, one-dimensional system composed of a vegetation canopy, snowcover (if present), litter, and soil profile. A conceptual diagram of the model structure is shown in Figure 11.3. The model integrates the detailed physics of interrelated mass and energy transfer through the multilayer system into one simultaneous solution. Hourly predictions include evaporation, transpiration, snow depth,...

Third temperature scenario

The third temperature scenario is given by a seasonal increase of the maximum temperatures. The model is run once again with the same initial and boundary conditions. At Disentis, a rise of the maximum temperatures diminishes the snowpack duration by seven days in D88-89 and by six days in D98-99. This scenario induces similar changes as the first, especially if the melting starts early Q*,AQm,Ts increase, AQs becomes more positive and the snow depth declines. If differences are calculated in...

Digital terrain model

The base digital terrain model (DTM) consists of 1-km resolution altitudes for the catchment. The 8-km resolution DTM was generated by averaging the 64 (or fewer at the catchment border) 1-km pixels within each 8-km cell (Figure 4.2). DTM correction, the catchment and subcatchment segmentation and the channel network analysis for the identification of the gauging station locations (Briancon, L'Argentiere and La Clapiere) were performed using the digital landscape analysis tool TOPAZ (Garbrecht...

Experiential information

Non Convex Fuzzy Sets

Measurements or estimates of physical and meteorological variables at the point or plot scale are associated with inherent errors or uncertainties. The up-scaling procedures used to scale up from the point or plot scale to the catchment scale introduce additional uncertainties, governed by the adequacy of the spatial extrapolation procedure used in the model. The interpretation or processing of point observations for obtaining the corresponding estimates at the catchment scale often rely on the...

Soil saturated conductivity after field data

Several different methods, both mono-dimensional (eventually with the introduction of scale effects, for example, Wu etal. 1999, Braud etal. 2001) and bi-dimensional with axial symmetry, have been presented and compared in the literature to interpret the infiltration process from a single ring infiltrometer. Here, two mono-dimensional quasi-steady methods and a two-dimensional axial-symmetric method are presented. The first method we used to estimate the soil vertical saturated conductivity Ks...

Site description

This study was conducted at the Wind River Canopy Crane Research Facility (WRCCRF), located within the T.T. Munger Research Natural Area of the Gifford Pinchot National Forest, in southwestern Washington, USA (Figure 11.1). The site is located on a gently sloping alluvial fan in the Wind River Valley in the Cascade Mountains. Site characteristics are listed in Table 11.1. A Liebherr 550HC tower crane is located in the center of the 4 ha study area, and was used as a sensor platform for...

Model description

The SEBM is similar to a land surface model formulation of intermediate complexity, such as those in GCMs and in RCMs, but it differs in details. It has a tiled surface structure including a distinct snow layer. The model is a physically based semiprognostic model, which computes explicitly the surface variables but needs atmospheric input variables in order to be run adequately. Therefore, it is driven by hourly input data of air temperature, Tair (K), dew point temperature, Td (K),...

Comparison between energy balance ground temperature and resistivity evolution

Figure 6.9 shows a comparison between the temperature change in the borehole, the radiation balance and the total resistivity variation at the borehole location. Thereby, the dominant role of the snow cover evolution becomes visible. A permanent snow cover was established at the end of October (Figure 6.9c) and persisted until mid-June. During that time, the temperature within the uppermost 10 m of the borehole remained almost constant (Figure 6.9a), as the ground temperature regime was...

Using Subgrid Parameterisation and a Forest Canopy Climate Model for Improving Forecasts of Snowmelt Runoff

ULRICH STRASSER1 AND PIERRE ETCHEVERS2 1 Department of Earth and Environmental Sciences, Section Geography, University of Munich, Munich, Germany, 2 Centre National de Recherches Meteorologiques, Centre d'Etudes de la Neige, METEO-France, Saint Martin Mountainous catchments are the origin of many large rivers and a major source of water availability. They not only are a local resource for freshwater supply and hydropower generation but also considerably influence the runoff regime of the...

Alpine Climate Change and Cryospheric Responses An Introduction

NSIDC CIRES, University of Colorado, Boulder, CO. 80309-0449, USA As an introduction to the following chapters dealing with changes in snow and ice conditions in high mountain regions, and their hydrological consequences, a brief overview of recent changes in alpine climates and associated cryospheric responses is presented. Direct observations and proxy records indicate that historical and recent changes in climate in many mountain regions of the world are at least comparable with, and locally...

Mountain Soils

STEFANO BARONTINI, ALBERTO CLERICI, ROBERTO RANZI AND Department of Civil Engineering, University of Brescia, Brescia, Via Branze 38, In mountain areas, the surface runoff can represent a large portion of the total runoff. This can be observed by analysing flood hydrographs of mountain watersheds the rising and falling limb of the stormflow hydrograph are very steep, and the baseflow recession is rapid, compared to that of basins with large floodplain areas. In a short time, generally a few...

Introduction Climate and Hydrology in Mountain Areas

Undoubtedly, the mountain regions of our world are the main hydrological and climatological triggers or pertubators of the water cycle as well as of complex meteorological patterns including phenomena such as the production or inhibition of rainfall. In terms of their role as water towers, mountain regions form an important supply of snow and or rain-fed water to the lowlands. In terms of climate, mountain systems develop a considerably complex system of their own, influenced by the often...

Effects of Frozen Soil on the Groundwater Recharge in Alpine Areas

DANIEL BAYARD1 AND MANFRED STAHLI2 1EPFLausanne, GEOLEP, ENAC, 1015 Lausanne, Switzerland, 2Swiss Federal Research Institute WSL, Zurcherstrasse 111, 8903 Birmensdorf, Switzerland Frozen ground is one of the most special features of alpine regions. At lower altitudes, soil frost forms seasonally, depending on weather, topography, snow cover and other surface properties, whereas at higher altitudes (and latitudes) a frost layer may persist year-round (permafrost). Soil frost not only makes great...

Evapotranspiration models for mountain valleys

Evapotranspiration models are of special interest for mountains in semi-arid or arid environments. Water management that relies on the role of water towers (Price & Barry 1997) requires improved hydrological models. Amongst important hydrometeorological parameters such as precipitation and ET, runoff is the only reliably measured regional hydrological component under mountain conditions (Whiting 2003). Of the remaining components, regional precipitation is even more difficult to determine...

Snow and ice penitentes

Penitentes were first described in the literature by Darwin (1839). On March 22, 1835, he had to squeeze his way through snowfields covered in penitentes near the Piuquenes Pass, on the way from Santiago de Chile to the Argentinian city of Mendoza, and reported the local belief (that is still held) that they were formed by the strong winds of the Andes. These pinnacles of snow or ice (Figure 3.3) grow over all glaciated and snow-covered areas in the Dry Andes above 4000m (Lliboutry 1954a,...

Dependence on temperature

The dependence of resistivity on temperature differs for temperatures above and below the freezing point. At temperatures above the freezing point, a decrease in temperature changes the resistivity of the material only in so far as the resistivity of the pore water is changed. A decrease in temperature increases the viscosity of water, in turn decreasing the mobility of the ions in the water, which increases the resistivity. A relationship between p and temperatures T above the freezing point...

Water retention relationships

Organic Fertilizer Water Retention

Some samples from the Toce River basin and from the Mella River basin were investigated to attempt a classification of the water retention parameters. The experimental water retention relationships are interpolated using the Gardner and the Brooks and Corey theoretical relationship. In Figure 9.10, the Brooks and Corey relationships of two different soils of the Toce River basin are plotted together with the experimental points. The variation of the pore-size distribution index X is also...

Richards equation and constitutive laws

The infiltration process is a particular case of the dynamic of a darcian flux in an unsaturated porous media. On the basis of a continuum meso-scale analysis, under the hypothesis of an isothermal process of an incompressible fluid in a non-deformable isotropic medium, the infiltration can be physically described by the known Fokker-Planck's or Richards' equation (Richards 1931) where e is the volumetric soil moisture, k' is the z-axis unitary vector, positive upward, and D(e) L2T 1 is the...

Simultaneous heat and water model SHAW validation

The SHAW model was modified using the 1999 dataset and validated using the 2000 dataset. The SHAW model is physically based and requires little calibration. Parameter adjustments during the development year were limited to measured and estimated soil properties (specifically, saturated hydraulic conductivity and the pore size distribution index) to more accurately simulate observed drainage trends. The model was validated against detailed measurements of snowcover, throughfall, and soil...

Solutions of Flow Equations and Measurements in the Alpine Toce Valley

MARILENA MENZIANI1, SERGIO PUGNAGHI1, SERGIO VINCENZI2 AND RENATO SANTANGELO1 1 Dipartimento di Ingegneria dei Materiali e dell'Ambiente - Osservatorio Geofisico, Universita di Modena e Reggio Emilia, Via Vignolese 905, 41100 Modena, Italy, 2ISMAR, Grandi Masse, CNR, S. Polo 1364, 30125 Venezia, Italy Hydrological models are based on the efficient and robust description of the different aspects of the hydrological cycle achieved by the parameterisation of the major pathways in this cycle...

Munich Germany

The hydrological importance of mountains has several aspects. The orographic effect and the resulting interaction with the atmosphere produce a highly enhanced precipitation input as compared to lowland areas. Moreover, winter precipitation is stored as snow cover and glacier ice and released, seasonally delayed, in spring and summer, when the demand for irrigation is highest. Not only the water benefits mountain regions themselves but also the rivers transport the surplus of water downstream...

Local scale measurements

At both sites, we set up a similar experiment. On a delimited soil plot (6 m2), the different components of the water balance were measured, that is, precipitation, snow water equivalent, surface runoff, subsurface runoff and deep percolation. At the lower edge of the plot, surface and subsurface runoff were collected from the depth intervals 0 to 3 cm and 3 to 28 cm, respectively (Figure 7.3). The collecting gutters were filled with gravel and sand so Figure 7.3 Schematic instrumental setup...

Runoff and Floods in the Alps An Overview

BALDASSARE BACCHI1 AND VIGILIO VILLI2 1 Department of Civil Engineering-University of Brescia - Via Branze, 38-25123 Brescia-I, 2 CNR - Research Institute for Hydrogeological Risk Prevention - Corso Stati Uniti, 4-35127Padova-I In this overview, the close links between meteorological and hydrological aspects in mountain areas are briefly discussed and state-of-the-art issues related to the influence of meteorological and surface processes on flood formation are presented. Although this paper is...

Assessment of Snowcovered Areas Using Air Temperatures During Melt in a Mountainous Basin

Mark The Satluj River Basin Map

PRATAP SINGH1 AND LARS BENGTSSON2 1 National Institute of Hydrology, Roorkee 247 667 (India), 2 Department of Water Resources Engineering, Lund University, S-221 00, Sweden Snow is a very important component of the hydrological cycle and it plays a vital role in the water resources in many parts of the world. In a region or basin, snow cover is developed from a series of winter storms and is depleted during spring and summer period because of warmer climate. Depending upon the location of the...

Target areas

Two Alpine basins were investigated during our campaigns the Toce River basin, located in the Northern Italian Alps, and the Mella River basin, in the Central Italian Alps (see Figure 9.3 and Table 9.1). The first basin was investigated during an international research project (Bacchi and Ranzi 2000), in an area close to Lago Maggiore, selected as a main scientific target in the Mesoscale Alpine Programme. In 1999, several experiments took place there, aimed at understanding the influence of...

Szrenica Giant Mountains Karkonosze Poland

The Szrenica study site (Figure 12.1) is a small headwater basin of the River Oder to the west of Mountain Szrenica (called Reiftr ger, in German meaning rime cap). It is part of the Giant Mountains and forms the natural and political boundary between Poland and the Czech Republic (Table 12.1). The Giant Mountains belong to one of the highest mountain chains in Silesia and mark the only region with mountain characteristics between Scandinavia and the Alps. Precipitation occurs on 62 of days...

Runoff calculations using different precipitation inputs

It was possible to apply the TACD model with very good success The Reff (Q) amounted to 0.94 and 0.85 and Reff (log Q) amounted to 0.99 and 0.90 during the calibration period for the Brugga basin and the St. Wilhelmer Talbach basin, respectively. The statistical measures for the model validation period showed also clearly the suitability of the TACD for runoff calculation Reff (Q) amounted to 0.80 and 0.85 and Reff (log Q) amounted to 0.83 and 0.87 for the Brugga basin and the St. Wilhelmer...

Catchments

University of Oldenburg, Institute of Biology and Environmental Sciences, PO Box 2503, D-26111 Oldenburg, Germany Coupled climatologic and hydrologic investigations of high mountain landscapes in Norway are a great challenge, especially where strong meteorological and topographical gradients dominate the boreal altitudinal zones. Human impacts during the past centuries have been important in these types of landscapes, especially involving logging, peat cutting, lichen harvesting for winter...

Sensitivity of energy balance and implications

This work has addressed the formation of penitentes through an experimental and modelling campaign in the Variation of EB components with height Variation of EB components with height Figure 3.8 Variation of the energy balance components with height for mean recorded values at the lower AWS (3335 m a.s.l.) applying a standard lapse rate (-0.0065 Km-1). Short-wave global radiation is modified primarily by albedo, which in this case was simplified to a constant value Figure 3.8 Variation of the...

Geophysical measurements DC resistivity tomography

The direct current (DC) resistivity technique is based on electrical resistivity differences between different subsurface materials. For typical permafrost material, a marked increase in resistivity at the freezing point was shown in several field and laboratory studies (Hoekstra et al. 1975, King et al. 1988). Consequently, the application of electric and electromagnetic techniques has a long tradition in the study of permafrost (for a review, see Scott et al. 1990, Vonder Muhll et al. 2001)....

List of Contributors

Yutaka Ageta, Department of Hydrospheric-Atmospheric Science, Graduate School of Environmental Studies, Nagoya University, Japan Baldassare Bacchi, Department of Civil Engineering, University of Brescia, Brescia, Italy Stefano Barontini, Department of Civil Engineering, University of Brescia, Italy Ana P. Barros, Pratt School of Engineering, Duke University, USA Roger G. Barry, NSIDC CIRES, University of Colorado, USA Daniel Bayard, EPF Lausanne, GEOLEP, ENAC, Switzerland Michel Beiand, Reseau...

Snow Penitentes

PURVES2 1 Institute of Hydromechanics and Water Resources Management, ETH - Z rich, 2 Department of Geography, University of Zurich, Switzerland The Dry Central Andes stretching from latitude 31 S to 35 S are climatic deserts, yet they support rich agriculture and large urban centres thanks to melt water from glaciers and snow-covered mountains. Most of the agriculture of the Chilean Central Valley is irrigated (Schwerdtfeger 1976), and all drinking water for...

Parameter uncertainty

Considerable uncertainty can be expected in the estimation of climatic input variables i.e. precipitation, temperature , of the observations with which we evaluate the model predictions i.e. discharge , and of the model parameter values i.e. soil moisture capacity . A new approach to dealing with these uncertainties in the computation of regional water balance is the objective of this work. As in all natural sciences, it is difficult to exactly determine the physical, hydrological and...

Simulations under contemporary conditions

Figure 18.3 shows observed and calculated hydrographs for one hydrological year in the Abramov region, where the best results have been achieved. For the Tuyuksu area, the quality of measured discharge is insufficient Hagg 2003 , and at Glacier No. 1, the short dataset of only four hydrological years does not allow intercomparison through time. Annual terms of the water balance in the three investigation areas, calculated by the HBV-ETH model, are shown in Table 18.3. Figure 18.3 Comparison...

Dischma Valley Grisons Switzerland

The Dischma catchment is located south of Davos in Graubuenden Grisons , eastern Switzerland near the Austrian border Figure 12.2 . It is a typical elongated, glaciated high alpine valley see Table 12.1 for details with a central NNW-SSE axis and the remains of the Scaletta glacier at its southern boundary Vogele 1984 . The climate in summer is dominated by low-pressure systems moving from the Weissfluhjoch in the north-west up the Dischma valley and occasionally replaced by a stable, alpine...