Hydrological and meteorological records from the Vernagtferner Basin - Vernagtbach station, for the years 2002 to 2012
In November 2001, two separate Campbell loggers ("Meteologger" and "Hydrologger&qu... more In November 2001, two separate Campbell loggers ("Meteologger" and "Hydrologger", both type CR23X) were installed at the Vernagtbach site in the Oetztal Alps, Austria (Latitude: 46.85; Longitude: 10.82; Elevation: 2640 m). On these loggers, 10-minutes centred averages for the meteorological data and 5-minutes centred averages for the hydrological data are recorded. The meteorological parameters comprise air temperature, humidity of the air, air pressure, four radiation components, wind direction and speed, precipitation and snow height. For air temperature, two records are published, recorded with a ventilated and an unventilated Pt-100 in a Stevenson screen; for precipitation, three time series are available: (I) the cumulative record of a weighing gauge for the whole year, (II) single events derived from (I), and (III) single events from a tipping bucket; (II) and (III) are only provided for the period 1, May to 31, October of each year. Wind records are also g...
Contribution of Snow and Ice Melt in the Upper Danube Discharge Today and in the Future
The hydrological model of the decision support system Danubia allows to determine the sources of ... more The hydrological model of the decision support system Danubia allows to determine the sources of runoff according to glacier melt, snow melt and rain at any location of the river network of the Upper Danube. The analysis shows for the passed decade that in glacierized head watersheds there is about an equal partitioning between runoff from ice melt, snow melt and rain (about 33 % each). Further downstream the portion of ice melt decreases sharply even under present-day conditions with the effect that finally 2 % of annual runoff is of glacial origin in Passau/Achleiten (basin area of about 77’000 km², current glaciation 0.5 %), and about ¾ comes from rain and ¼ from snow melt. This latter fraction is about twice as high as compared to subbasins lying exclusively in the lowlands without connection to the alpine region. Using the regionally adapted REMO scenario data based on the IPCC emission scenario A1B the future development of runoff sources is calculated, taking into account the...
Influence of snow accumulation and annual glacier mass balance on the calibration results of a spatially distributed conceptual hydrological model
ABSTRACT This contribution uses a conceptual hydrological model to investigate the interdependenc... more ABSTRACT This contribution uses a conceptual hydrological model to investigate the interdependence of additional calibration criteria and attempts to find more realistic parameter sets for model calibration. In the Vernagt basin, Oetztal Alps, a spatially distributed runoff model was set up and 10,000 random parameter sets have been generated and tested. The best set was selected using runoff as well as winter accumulation and annual glacier mass balances as objective functions. The incorporation of additional criteria leads to different parameter sets and slightly poorer runoff simulation compared to a calibration by runoff only. The relation between these different variables shows an interesting pattern. While the quality of glacier mass balance and runoff simulations clearly depend on each other and therefore good runoff simulations are connected with good mass balance simulations and vice versa, good runoff or annual mass balance simulations have no influence on the quality of simulated winter accumulation. On the other hand, a proper description of winter accumulation induces fairly good runoff or annual mass balance simulations. Runoff, the glacier-wide winter accumulation and the annual mass balance in the ablation area could be simulated well, while the annual balance in the accumulation area showed larger inaccuracies. The simulations show a systematic overestimation of snow water equivalent in the accumulation area in the ablation period. Possible reasons for this error are discussed. The proper simulation of the processes during the 2003 heat wave proves that the model delivers reliable results also for meteorological conditions different from those during calibration.
Water balance of the Vernagtferner high alpine basin based on long-term measurements and modelling
Landschaftsökol. …, 2005
Long-term monitoring of the Vernagtferner (approx. 9 km²) annual glacier mass balance since 1964,... more Long-term monitoring of the Vernagtferner (approx. 9 km²) annual glacier mass balance since 1964, along with measurements of precipitation and other climatological variables and discharge since 1974 at the gauging station “Pegelstation Vernagtbach”, ...
Measurement and simulation of runoff from Nepalese head watersheds
The contribution of meltwater from snow and glaciers strongly determines runoff from high mountai... more The contribution of meltwater from snow and glaciers strongly determines runoff from high mountain regions. Hydrometeorological data are required in order to make an assessment of water resources; however, monitoring in remote areas is difficult, and typically, data series are discontinuous. This paper describes a procedure to bridge data gaps in daily values of precipitation and air temperature from high mountain stations in Nepal based on continuous measurement records of the meteorological service network with stations located mainly in lowland areas. In a second step, a conceptual precipitation-runoff model is calibrated and verified in three Himalayan head watersheds. Discharge is calculated using a daily time step over a total of seven hydrological years. This approach enables the assessment of the temporal and spatial distribution of runoff from high mountain areas such as the Nepalese Himalaya, and forms a valuable basis for water resources planning and management, i.e. hydr...
Assessment of annual snow accumulation over the past 10 years at high elevations in the Langtang region
… -Publications of the …, 1993
... IAHS Publ., this volume. Grabs, WE &Pokhrel, AP (1993) Establishment of a measuring s... more ... IAHS Publ., this volume. Grabs, WE &Pokhrel, AP (1993) Establishment of a measuring service for snow and glacier hydrology in Nepal: conceptual and operational aspects. IAHS Publication, this volume. ... 5, 63-68. Miller, MM, Laventhal, JS & Libby, WF (1965) Tritium in Mt. ...
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
This study investigates the influence of snowmelt model structure on the overall performance of r... more This study investigates the influence of snowmelt model structure on the overall performance of runoff modelling in various-sized basins, where the snow cover is typically short-lived and rather thin. The per¬ formance of the following snowmelt models is compared: temperature-index method (Bergstrom, 1976) ; temperature and wind-index method; combination method (Anderson, 1973); extended combination method (using also water vapour pressure as an input variable) energy balance method. The performance is assessed by comparing linear scale plots of measu¬ red and simulated discharge and by applying the numerical efficiency criterion according to Nash and Sutcliffe (1970). For a given catchment, melt rates as calculated by the various snowmelt models are used as input to one and the same runoff model. In the small-scale Rietholzbach basin (3.18 km2), meteorological data as used in this study are measured at a point having a temporal resolu¬ tion of one hour and are considered representa...
This paper is a valuable contribution to the knowledge of glacial hydrology in the Caucasus Area.... more This paper is a valuable contribution to the knowledge of glacial hydrology in the Caucasus Area. It is worth to be published, however, it needs many minor revisions that are directly put into the manuscript. I am attaching the scan of the annotated manuscript and hope that the authos can include them.
During the melt season of 1978, the nature of snow and ice storage, the energy sources and the st... more During the melt season of 1978, the nature of snow and ice storage, the energy sources and the stream flow response were investigated at a site, a small-scale and a meso-scale watershed in the Coast Mountains of British Columbia, Canada. Differences in system internal homogeneity and system response times at each of these scales indicated the usefulness of this empirical classification. It is also demonstrated that different methods of analysis of snowmelt systems are appropriate at the different scales.
Many conceptual runoff models are well able to simulate daily discharge based on a rather modest ... more Many conceptual runoff models are well able to simulate daily discharge based on a rather modest data input (e.g. daily values of air temperature and precipitation) provided that calibration via discharge is possible. The underlying assumption is that no considerable losses or gains of water take place via subterranean pathways. This study reports on the application of an operationally used conceptual runoff model in a 96 km 2 Swiss alpine watershed known to exhibit a complex karst-related hydrological behaviour. Three additional model parameters are introduced, one taking into account aspect-dependent snow melt, and two parameters controlling karst-related water losses. The values of these additional parameters are derived externally, and optimal values of the remaining parameters are achieved by a manual calibration procedure on the basis of discharge. A plausible complete water balance and satisfactory snow storage simulations are achieved by means of this extended model. It can be concluded that a rather simple conceptual model can be applied in karst basins under the assumption that certain intermediate model results can be optimized and verified with the aid of additional measurements apart from the standard hydrometeorological network.
The water equivalent (SWE) of the seasonal snow cover can be an important component of the water ... more The water equivalent (SWE) of the seasonal snow cover can be an important component of the water cycle in mountainous areas, and the knowledge of this temporary storage term may for example be very valuable for predicting seasonal discharge, for making short-range discharge forecasts and also for assessing water quality aspects. Direct measurements of the SWE usually refer to index points and are seldom part of the standard meteorological networks. Therefore it may be advantageous to simulate this storage term based on the available meteorological data. The choice of the appropriate type of model will largely depend on the purpose of the simulation and the data availability. For operational forecasting and prediction practices, various conceptual models describing snow accumulation, melt and internal processes as well as runoff processes in a rather general way are usually sufficient if a minimal data requirement is met. To answer more complex questions such as the hydrological cons...
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