scholarly journals Experimental Hydrological Analyses in the Dischma based on Daily and Seasonal Evaporation

2002 ◽  
Vol 33 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Carmen de Jong ◽  
Franz K. List ◽  
Peter J. Ergenzinger
Keyword(s):  
Water Cycle ◽  
Source Area ◽  
Field Measurements ◽  
High Mountain ◽  
River Rhine ◽  
Climatic Fluctuations ◽  
Discharge Data ◽  
Mountain Valley ◽  
Accurate Picture ◽  
Single Station

The Dischma is a typical high mountain valley in the alpine source area of the River Rhine. A knowledge of the daily and seasonal water balance is important for understanding and predicting the effects of climatic fluctuations on river discharge. Traditional methods of analysing the water cycle usually involve deriving evaporation from precipitation and discharge. However, in mountain regions single station precipitation and discharge data cannot simply be extrapolated to represent regional evaporation characteristics. Measurements of precipitation in mountains are both limited in accuracy and spatial representativeness in contrast to well-defined discharge data. Field measurements of evaporation in the Dischma valley recorded over five summers give a fairly accurate picture of this component over space and time. New results on the characteristics of evaporation, transpiration and condensation are obtained from automated evaporation pans, lysimeters and climatological stations. The water cycle can be defined with greater precision by measuring discharge and evaporation and deriving precipitation than the more traditional technique of deriving evaporation.

scholarly journals Multi‐year observations of the high mountain water cycle in the Langtang catchment, Central Himalaya

2021 ◽  
Author(s):  
Jakob F. Steiner ◽  
Tika R. Gurung ◽  
Sharad P. Joshi ◽  
Inka Koch ◽  
Tuomo Saloranta ◽  
...  
Keyword(s):  
Water Cycle ◽  
High Mountain ◽  
Central Himalaya

scholarly journals Health and sustainability of glaciers in High Mountain Asia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Evan Miles ◽  
Michael McCarthy ◽  
Amaury Dehecq ◽  
Marin Kneib ◽  
Stefan Fugger ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Field Measurements ◽  
Tien Shan ◽  
High Mountain ◽  
Specific Mass ◽  
Ice Flow ◽  
Ice Volume ◽  
Mass Redistribution ◽  
Glacier Ablation

AbstractGlaciers in High Mountain Asia generate meltwater that supports the water needs of 250 million people, but current knowledge of annual accumulation and ablation is limited to sparse field measurements biased in location and glacier size. Here, we present altitudinally-resolved specific mass balances (surface, internal, and basal combined) for 5527 glaciers in High Mountain Asia for 2000–2016, derived by correcting observed glacier thinning patterns for mass redistribution due to ice flow. We find that 41% of glaciers accumulated mass over less than 20% of their area, and only 60% ± 10% of regional annual ablation was compensated by accumulation. Even without 21st century warming, 21% ± 1% of ice volume will be lost by 2100 due to current climatic-geometric imbalance, representing a reduction in glacier ablation into rivers of 28% ± 1%. The ablation of glaciers in the Himalayas and Tien Shan was mostly unsustainable and ice volume in these regions will reduce by at least 30% by 2100. The most important and vulnerable glacier-fed river basins (Amu Darya, Indus, Syr Darya, Tarim Interior) were supplied with >50% sustainable glacier ablation but will see long-term reductions in ice mass and glacier meltwater supply regardless of the Karakoram Anomaly.

scholarly journals Changing the geometry of basins and water resources of Lakes Gopło and Ostrowskie under the influence of anthropopressure

2014 ◽  
Vol 14 (1) ◽  
pp. 33-43 ◽  
Author(s):  
Piasecki Adam ◽  
Skowron Rajmund
Keyword(s):  
Water Resources ◽  
Surface Area ◽  
Water Cycle ◽  
Field Measurements ◽  
Aerial Photographs ◽  
Maximum Width ◽  
Digital Terrain ◽  
Terrain Models ◽  
Basic Parameters ◽  
Area And Volume

Abstract The paper presents the changes that have occurred in the morphometry of Lakes Gopło and Ostrowskie, which are located in central Poland. The analysis covered the period characterised by increased human interference into the water cycle, which has been taking place continually since the mid-eighteenth century. On the basis of available cartographic materials (aerial photographs, topographic maps, bathymetric charts of the lakes) and the authors’ own field measurements digital terrain models were developed for the immediate environment of the surveyed lakes. These models, in turn, were used for measuring basic parameters characterising the external dimensions of the lakes (surface area, length and maximum width, shoreline length) and their underwater relief (volume, maximum and average depth). In addition, the selected indicators of the shape and form of the lake basins were determined. The results showed a drastic reduction of water resources of the two lakes. The basin of Lake Gopło covers only the deepest parts of the former reservoir, accounting for only 23.3% of the lake before 1772, and 32.5% of its former volume. In the case of Lake Ostrowskie the surface area and volume decreased, respectively, by 23.5% (74.9 ha) and 21.3% (6 695 000 m3). Such large changes in surface area and volume of both lakes have contributed to significant changes in other morphometric parameters and indicators. In particular, significant changes were observed in relation to such morphometric characteristics as length and maximum width, as well as average and maximum depth.

scholarly journals The hydrological significance of mountains: from regional to global scale

2004 ◽  
Vol 8 (6) ◽  
pp. 1017-1030 ◽  
Author(s):  
D. Viviroli ◽  
R. Weingartner
Keyword(s):  
Fresh Water ◽  
Significant Proportion ◽  
Arid Zones ◽  
River Rhine ◽  
European Alps ◽  
Rhine River ◽  
Runoff Water ◽  
Mountain Areas ◽  
Discharge Data ◽  
Total Discharge

Abstract. Mountain regions supply a large share of the world’s population with fresh water. Quantification of the hydrological significance of mountains, however, is subject to great uncertainty. Instead of focusing on global averages in advance, the present analysis follows a catchment-based approach using discharge data provided by the Global Runoff Data Centre (GRDC). The River Rhine originating in the European Alps is chosen as a first study area, revealing the hydrological relationship between mountainous and lowland regions in a well-documented area. Following the findings from this analysis, different aspects of runoff characteristics for a total of 22 case-study river basins world-wide have been investigated and compared, for a global view. The view has been extended through aspects of climate and human use of mountain runoff. The particular hydrological characteristics of mountain areas are characterised by disproportionately large discharges. In humid areas, mountains supply up to 20–50% of total discharge while in arid areas, mountains contribute from 50–90% of total discharge, with extremes of over 95%. The overall assessment of the hydrological significance of mountain areas reveals that the world’s major "water towers" are found in arid or semi-arid zones where they provide essential fresh water for a significant proportion of a quickly growing global population. Keywords: mountain hydrology, global comparative assessment, runoff, water resources, sustainability, Rhine River, European Alps

Comparison of field measurements to predicted reaeration coefficients, k2, in the application of a water quality model, QUAL2E, to a tropical river

2002 ◽  
Vol 46 (9) ◽  
pp. 47-54 ◽  
Author(s):  
M. Mohamed ◽  
J.D. Stednick ◽  
F.M. Smith
Keyword(s):  
Water Quality ◽  
Standard Error ◽  
Field Measurements ◽  
Water Quality Modeling ◽  
Low Flow ◽  
Quality Model ◽  
Predictive Equations ◽  
Discharge Data ◽  
Study Results ◽  
Reaeration Coefficient

Some of the many tools used for watershed management are mathematical and computer models for wasteload allocations. QUAL2E is one of the most popular water quality models used for such purposes. The question arises as to whether the model is applicable in a different climate such as that in the tropics. In this study, QUAL2E was used to model Sg. Selangor River in Malaysia using the predictive equations for reaeration coefficient (k2) within the model and the measured reaeration coefficients for the river. The study results indicated that use of the reaeration coefficient (k2) measured at Sg. Selangor River did give the lowest standard error (SE) for the simulation of water quality during the 7Q10 low-flow period which is considered as the worst scene scenario in water quality modeling. But during calibration and validation using actual low-flow discharge data, the measured reaeration coefficients did not give the lowest standard error (SE). In conclusion, the results indicated that QUAL2E is applicable in tropical rivers when used with the modeled river parameters (i.e. hydraulic parameters, meteorological conditions etc.). Measured reaeration coefficients produced good results and several predictive equations also produced comparatively good results.

scholarly journals Aeolian Remobilisation of Volcanic Ash: Outcomes of a Workshop in the Argentinian Patagonia

2020 ◽  
Vol 8 ◽  
Author(s):  
Paul A. Jarvis ◽  
Costanza Bonadonna ◽  
Lucia Dominguez ◽  
Pablo Forte ◽  
Corine Frischknecht ◽  
...  
Keyword(s):  
Volcanic Ash ◽  
Friction Velocity ◽  
Critical Infrastructure ◽  
Dust Emission ◽  
Source Area ◽  
Field Measurements ◽  
Volcanic Eruptions ◽  
Field Studies ◽  
Sediment Traps ◽  
Economic Sectors

During explosive volcanic eruptions, large quantities of tephra can be dispersed and deposited over wide areas. Following deposition, subsequent aeolian remobilisation of ash can potentially exacerbate primary impacts on timescales of months to millennia. Recent ash remobilisation events (e.g., following eruptions of Cordón Caulle 2011; Chile, and Eyjafjallajökull 2010, Iceland) have highlighted this to be a recurring phenomenon with consequences for human health, economic sectors, and critical infrastructure. Consequently, scientists from observatories and Volcanic Ash Advisory Centers (VAACs), as well as researchers from fields including volcanology, aeolian processes and soil sciences, convened at the San Carlos de Bariloche headquarters of the Argentinian National Institute of Agricultural Technology to discuss the “state of the art” for field studies of remobilised deposits as well as monitoring, modeling and understanding ash remobilisation. In this article, we identify practices for field characterisation of deposits and active processes, including mapping, particle characterisation and sediment traps. Furthermore, since forecast models currently rely on poorly-constrained dust emission schemes, we call for laboratory and field measurements to better parameterise the flux of volcanic ash as a function of friction velocity. While source area location and extent are currently the primary inputs for dispersion models, once emission schemes become more sophisticated and better constrained, other parameters will also become important (e.g., source material volume and properties, effective precipitation, type and distribution of vegetation cover, friction velocity). Thus, aeolian ash remobilisation hazard and associated impact assessment require systematic monitoring, including the development of a regularly-updated spatial database of resuspension source areas.

scholarly journals Measuring variations of δ<sup>18</sup>O and δ<sup>2</sup>H in atmospheric water vapour using laser spectroscopy: an instrument characterisation study

2012 ◽  
Vol 5 (1) ◽  
pp. 1597-1655 ◽  
Author(s):  
F. Aemisegger ◽  
P. Sturm ◽  
P. Graf ◽  
H. Sodemann ◽  
S. Pfahl ◽  
...  
Keyword(s):  
Water Vapour ◽  
Laboratory Experiments ◽  
Water Cycle ◽  
Field Measurements ◽  
Detailed Knowledge ◽  
Spectroscopic Techniques ◽  
Mixing Ratio ◽  
Atmospheric Water ◽  
Uncertainty Estimates ◽  
Laser Spectroscopic

Abstract. Variations of stable water isotopes in water vapour have become measurable at a measurement frequency of about 1 Hz in recent years using novel laser spectroscopic techniques. This enables us to perform continuous measurements for process-based investigations of the atmospheric water cycle at the time scales relevant for synoptic meteorology. An important prerequisite for the interpretation of data from automated field measurements lasting for several weeks or months is a detailed knowledge about instrument properties and the sources of measurement uncertainty. We present here a comprehensive characterisation and comparison study of two commercial laser spectroscopic systems based on cavity ring-down spectroscopy (Picarro) and off-axis integrated cavity output spectroscopy (Los Gatos Research). The uncertainty components of the measurements were first assessed in laboratory experiments, focussing on the effects of (i) water vapour mixing ratio, (ii) measurement stability, (iii) uncertainties due to calibration and (iv) response times of the isotope measurements due to adsorption-desorption processes on the tubing and measurement cavity walls. Based on the experience from our laboratory experiments we set up a one-week field campaign for comparing measurements of the ambient isotope signals of the two laser spectroscopic systems. The optimal calibration strategy determined for both instruments was applied as well as the correction functions for water vapour mixing ratio effects. The root mean square difference between the isotope signals from the two instruments during the field deployment was 2.3‰ for δ2H, 0.5‰ for δ18O and 3.1‰ for deuterium excess. These uncertainty estimates from field measurements compare well to those found in the laboratory experiments. The present quality of measurements from laser spectroscopic instruments combined with a calibration system opens new possibilities for investigating the atmospheric water cycle and the land-atmosphere moisture fluxes.

Supporting Respect: Community Partnership in Alamosa, Colorado

2012 ◽  
Vol 34 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Sheryl Ludwig ◽  
Francisco Lucas ◽  
Lucia Nicolas ◽  
Flora Archuleta ◽  
Antonio Sandoval ◽  
...  
Keyword(s):  
Culture Change ◽  
Agricultural Fields ◽  
High Mountain ◽  
Community Partnership ◽  
San Luis Valley ◽  
Community Groups ◽  
Mountain Valley ◽  
San Luis

Q'anjob'al speaking Maya from western highland villages, primarily Santa Eulalia, of Huehuetenango, Guatemala, first arrived in southern Colorado's San Luis Valley in 1979. Since then hundreds more have come to work in the valley's agricultural fields and the mushroom farm located in Alamosa. Currently 400 or more documented and/or undocumented adults and their school-attending children live, work, and raise families in this economically impoverished, rural, high mountain valley region of Colorado. This paper presents an overview of how community groups came together to create education and culture change in Alamosa.

scholarly journals Flood risk assessment and cultural heritage impact in the Instituto Superior de Arte (ISA) in Habana.

2020 ◽  
Author(s):  
Daniele Fabrizio Bignami ◽  
Leonardo Stucchi ◽  
Daniele Bocchiola ◽  
Christian Zecchin ◽  
Davide Del Curto ◽  
...  
Keyword(s):  
Flood Risk ◽  
Laser Scanner ◽  
Drainage System ◽  
Digital Terrain Model ◽  
Field Measurements ◽  
Point Of View ◽  
Discharge Data ◽  
Terrain Model ◽  
Critical Discharge ◽  
The Status

&lt;p&gt;Keeping ISA Modern is a project of Fondazione Politecnico di Milano and other partners aimed at planning the conservation of some of the buildings (Schools) of the University of Arts (ISA) of Cuba, built over a former country club, designed by eminent architects of the time (Vittorio Garatti, Roberto Gottardi and Ricardo Porro), and bestowed with the status of UNESCO World Heritage in 2003.&lt;/p&gt;&lt;p&gt;Most of the Schools are currently unusable, also due to damages caused by frequent floods from the surrounding Rio Quib&amp;#249; river, and they need urgent restoration if they are to be used. Personnel of Politecnico di Milano carried out a field survey on the Rio Quib&amp;#249; during 2019, and also based upon information from the Cuban National Institute of Hydraulic Resources (INRH) they studied established flood risk for ISA.&lt;/p&gt;&lt;p&gt;Here, we built a high-resolution digital terrain model (DTM) of the park where Schools are located, using laser scanner data, and previously georeferenced points. Using field measurements taken in June 2019 we were able to assess geometry (included bridges), slope and roughness coefficients of the main channel of the Quib&amp;#249; river, influence of the sea level. Then using as input critical discharge data provided by INRH we evaluated flood area and flood volume for 4 representative return periods (5, 20, 50, 100 years).&lt;/p&gt;&lt;p&gt;The most impacted building is the School of Ballet, located within a narrow meander of Rio Quib&amp;#249;, immediately upstream of a narrow bridge, clogging largely during floods, only 1 km far from the sea, and with drainage system unable to discharge storm water.&lt;/p&gt;&lt;p&gt;Given the high required cost, a partially collapsed wall originally partially protecting the School of Ballet was not rebuilt, and we are now exploring flood mitigation strategy which are cheaper, and feasible from the point of view of compatibility with the historical and architectural value of the building.&lt;/p&gt;

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