Ash on Snow a Tool – A Tool to Prevent Flooding?

Years with late spring in combination with thick snow-pack constitute risk for flooding. To decrease that risk, the possibility of spreading albedo-lowering material (wood ash) on parts of a basin snow has been examined. By blackening the snow more solar radiation is absorbed and the snowmelt is enhanced. If sun-exposed parts of the basin are ash-treated (before normal runoff starts) the runoff will be distributed over a longer period of time and the risk of flooding will be reduced. Wood ash in different concentrations was spread on small snow plots and melt rates and albedo were measured. For snow covered with 0.03 kg ash m−2, the albedo was decreased from ≈ 0.60 for natural snow to ≈ 0.25, resulting in ≈ 90% more absorbed short-wave radiation. Melt on the ash treated surface, (daily average snow water equivalent), was 70% larger than melt on natural snow (12 and 7 mm d−1 respectively). A five times larger concentration (0.15 kg m−2) only increased the melt rate to 14 mm d−1. The temperature-index method was shown to be inadequate for modelling the melt rate for the ash treated snow. A radiation-index model, based on absorbed incoming short wave radiation, was shown to model the melt rate better than the temperature-index method.

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An 18-yr long (1993–2011) snow and meteorological dataset from a mid-altitude mountain site (Col de Porte, France, 1325 m alt.) for driving and evaluating snowpack models

Earth System Science Data ◽

10.5194/essd-4-13-2012 ◽

2012 ◽

Vol 4 (1) ◽

pp. 13-21 ◽

Cited By ~ 85

Author(s):

S. Morin ◽

Y. Lejeune ◽

B. Lesaffre ◽

J.-M. Panel ◽

D. Poncet ◽

...

Keyword(s):

Snow Depth ◽

Snow Water Equivalent ◽

Meteorological Data ◽

Model Performance ◽

Short Wave ◽

Wave Radiation ◽

Density Profiles ◽

The Public ◽

Snow Water ◽

Snowpack Properties

Abstract. A quality-controlled snow and meteorological dataset spanning the period 1 August 1993–31 July 2011 is presented, originating from the experimental station Col de Porte (1325 m altitude, Chartreuse range, France). Emphasis is placed on meteorological data relevant to the observation and modelling of the seasonal snowpack. In-situ driving data, at the hourly resolution, consist of measurements of air temperature, relative humidity, windspeed, incoming short-wave and long-wave radiation, precipitation rate partitioned between snow- and rainfall, with a focus on the snow-dominated season. Meteorological data for the three summer months (generally from 10 June to 20 September), when the continuity of the field record is not warranted, are taken from a local meteorological reanalysis (SAFRAN), in order to provide a continuous and consistent gap-free record. Data relevant to snowpack properties are provided at the daily (snow depth, snow water equivalent, runoff and albedo) and hourly (snow depth, albedo, runoff, surface temperature, soil temperature) time resolution. Internal snowpack information is provided from weekly manual snowpit observations (mostly consisting in penetration resistance, snow type, snow temperature and density profiles) and from a hourly record of temperature and height of vertically free ''settling'' disks. This dataset has been partially used in the past to assist in developing snowpack models and is presented here comprehensively for the purpose of multi-year model performance assessment. The data is placed on the PANGAEA repository (http://dx.doi.org/10.1594/PANGAEA.774249) as well as on the public ftp server ftp://ftp-cnrm.meteo.fr/pub-cencdp/.

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Snow water equivalent modeling components in NewAge-JGrass

Geoscientific Model Development ◽

10.5194/gmd-7-725-2014 ◽

2014 ◽

Vol 7 (3) ◽

pp. 725-736 ◽

Cited By ~ 12

Author(s):

G. Formetta ◽

S. K. Kampf ◽

O. David ◽

R. Rigon

Keyword(s):

Goodness Of Fit ◽

Hydrological Modeling ◽

Snow Water Equivalent ◽

Short Wave ◽

Wave Radiation ◽

Radiation Balance ◽

Time Step ◽

Vector Mode ◽

Snow Water ◽

Snow Model

Abstract. This paper presents a package of modified temperature-index-based snow water equivalent models as part of the hydrological modeling system NewAge-JGrass. Three temperature-based snow models are integrated into the NewAge-JGrass modeling system and use many of its components such as those for radiation balance (short wave radiation balance, SWRB), kriging (KRIGING), automatic calibration algorithms (particle swarm optimization) and tests of goodness of fit (NewAge-V), to build suitable modeling solutions (MS). Similarly to all the NewAge-JGrass components, the models can be executed both in raster and in vector mode. The simulation time step can be daily, hourly or sub-hourly, depending on user needs and availability of input data. The MS are applied on the Cache la Poudre River basin (CO, USA) using three test applications. First, daily snow water equivalent is simulated for three different measurement stations for two snow model formulations. Second, hourly snow water equivalent is simulated using all the three different snow model formulae. Finally, a raster mode application is performed to compute snow water equivalent maps for the whole Cache la Poudre Basin.

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TOPMELT 1.0: a topography-based distribution function approach to snowmelt simulation for hydrological modelling at basin scale

Geoscientific Model Development ◽

10.5194/gmd-12-5251-2019 ◽

2019 ◽

Vol 12 (12) ◽

pp. 5251-5265 ◽

Cited By ~ 6

Author(s):

Mattia Zaramella ◽

Marco Borga ◽

Davide Zoccatelli ◽

Luca Carturan

Keyword(s):

Solar Radiation ◽

Snow Water Equivalent ◽

Distributed Model ◽

Temporal Aggregation ◽

Time Step ◽

Temperature Index ◽

Index Model ◽

Clear Sky ◽

Basin Scale ◽

Snow Water

Abstract. Enhanced temperature-index distributed models for snowpack simulation, incorporating air temperature and a term for clear sky potential solar radiation, are increasingly used to simulate the spatial variability of the snow water equivalent. This paper presents a new snowpack model (termed TOPMELT) which integrates an enhanced temperature-index model into the ICHYMOD semi-distributed basin-scale hydrological model by exploiting a statistical representation of the distribution of clear sky potential solar radiation. This is obtained by discretizing the full spatial distribution of clear sky potential solar radiation into a number of radiation classes. The computation required to generate a spatially distributed water equivalent reduces to a single calculation for each radiation class. This turns into a potentially significant advantage when parameter sensitivity and uncertainty estimation procedures are carried out. The radiation index may be also averaged in time over given time periods. Thus, the model resembles a classical temperature-index model when only one radiation class for each elevation band and a temporal aggregation of 1 year is used, whereas it approximates a fully distributed model by increasing the number of the radiation classes and decreasing the temporal aggregation. TOPMELT is integrated within the semi-distributed ICHYMOD model and is applied at an hourly time step over the Aurino Basin (also known as the Ahr River) at San Giorgio (San Giorgio Aurino), a 614 km2 catchment in the Upper Adige River basin (eastern Alps, Italy) to examine the sensitivity of the snowpack and runoff model results to the spatial and temporal aggregation of the radiation fluxes. It is shown that the spatial simulation of the snow water equivalent is strongly affected by the aggregation scales. However, limited degradation of the snow simulations is achieved when using 10 radiation classes and 4 weeks as spatial and temporal aggregation scales respectively. Results highlight that the effects of space–time aggregation of the solar radiation patterns on the runoff response are scale dependent. They are minimal at the scale of the whole Aurino Basin, while considerable impact is seen at a basin scale of 5 km2.

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A 18-yr long (1993–2011) snow and meteorological dataset from a mid-altitude mountain site (Col de Porte, France, 1325 m alt.) for driving and evaluating snowpack models

Earth System Science Data Discussions ◽

10.5194/essdd-5-29-2012 ◽

2012 ◽

Vol 5 (1) ◽

pp. 29-45 ◽

Cited By ~ 5

Author(s):

S. Morin ◽

Y. Lejeune ◽

B. Lesaffre ◽

J.-M. Panel ◽

D. Poncet ◽

...

Keyword(s):

Snow Depth ◽

Snow Water Equivalent ◽

Meteorological Data ◽

Model Performance ◽

Short Wave ◽

Wave Radiation ◽

Density Profiles ◽

The Public ◽

Snow Water

Abstract. A quality-controlled snow and meteorological dataset spanning the period 1 August 1993–31 July 2011 is presented, originating from the experimental station Col de Porte (1325 m altitude, Chartreuse range, France). Emphasis is placed on meteorological data relevant to the observation and modelling of the seasonal snowpack. In-situ driving data, at the hourly resolution, consist in measurements of air temperature, relative humidity, wind speed, incoming short-wave and long-wave radiation, precipitation rate partitioned between snow- and rainfall, with a focus on the snow-dominated season. Meteorological data for the three summer months (generally from 10 June to 20 September), when the continuity of the field record is not warranted, are taken from a local meteorological reanalysis (SAFRAN), in order to provide a continuous and consistent gap-free record. Evaluation data are provided at the daily (snow depth, snow water equivalent, runoff and albedo) and hourly (snow depth, albedo, runoff, surface temperature, soil temperature) time resolution. Internal snowpack information are provided from weekly manual snowpit observations (mostly consisting in penetration resistance, snow type, snow temperature and density profiles) and from a hourly record of temperature and height of vertically free "settling" disks. This dataset has been partially used in the past to assist in developing snowpack model and is presented here comprehensively for the purpose of multi-year model performance assessment. The data is placed on the PANGAEA repository (http://doi.pangaea.de/10.1594/PANGAEA.774249) as well as on the public ftp server ftp://ftp-cnrm.meteo.fr/pub-cencdp/.

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Modelling Snow Accumulation and Snowmelt in the Bystřice River Basin

Geografie ◽

10.37040/geografie2012117010110 ◽

2012 ◽

Vol 117 (1) ◽

pp. 110-125 ◽

Cited By ~ 2

Author(s):

Lucie Kutláková ◽

Michal Jeníček

Keyword(s):

River Basin ◽

Snow Water Equivalent ◽

Snow Accumulation ◽

Mountain Areas ◽

Index Method ◽

Temperature Index ◽

Snow Water ◽

Rainfall Runoff Model ◽

Runoff Model ◽

Winter Flood

Effectively dealing with spring flooding issues should focus primarily on their causes. It is therefore important to study the processes of snow accumulation and snowmelt, especially in mountain areas. In this article, we use the lumped modelling approach of the rainfall-runoff model HEC-HMS, along with the temperature-index method for snow accumulation and snowmelt computation. Three winter periods were used for model calibration and testing: 2005/06, 2007/08 and 2008/09. Developments in the snow-water equivalent were simulated and the accuracy of simulated hydrographs was assessed, against actual observations, in the Ostrov outlet in the Bystřice River basin in the Krušné Hory Mountains. The published results present fundamental uncertainties in winter flood modelling and demonstrate the influence of the course and character of a given winter on the model’s capability to simulate the snow water equivalent and runoff.

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Excitation of Short-Wave Radiation by Nonrelativistic Oscillators

2007 International Kharkiv Symposium Physics and Engrg. of Millimeter and Sub-Millimeter Waves (MSMW) ◽

10.1109/msmw.2007.4294737 ◽

2007 ◽

Author(s):

A.N. Antonov ◽

V.A. Buts ◽

A.M Egorov ◽

O.F. Kovpik ◽

E.A. Kornilov ◽

...

Keyword(s):

Short Wave ◽

Wave Radiation ◽

Short Wave Radiation

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Evaluating the Effects of Façade Greening on Human Bioclimate in a Complex Urban Environment

Advances in Meteorology ◽

10.1155/2015/747259 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 43

Author(s):

Britta Jänicke ◽

Fred Meier ◽

Marie-Therese Hoelscher ◽

Dieter Scherer

Keyword(s):

Heat Stress ◽

Short Wave ◽

Wave Radiation ◽

Short Wave Radiation ◽

Long Wave ◽

Building Facades ◽

Urban Heat ◽

The Mean ◽

Human Bioclimate ◽

Radiant Temperature

The evaluation of the effectiveness of countermeasures for a reduction of urban heat stress, such as façade greening, is challenging due to lacking transferability of results from one location to another. Furthermore, complex variables such as the mean radiant temperature(Tmrt)are necessary to assess outdoor human bioclimate. We observedTmrtin front of a building façade in Berlin, Germany, which is half-greened while the other part is bare.Tmrtwas reduced (mean 2 K) in front of the greened compared to the bare façade. To overcome observational shortcomings, we applied the microscale models ENVI-met, RayMan, and SOLWEIG. We evaluated these models based on observations. Our results show thatTmrt(MD = −1.93 K) and downward short-wave radiation (MD = 14.39 W/m2) were sufficiently simulated in contrast to upward short-wave and long-wave radiation. Finally, we compare the simulated reduction ofTmrtwith the observed one in front of the façade greening, showing that the models were not able to simulate the effects of façade greening with the applied settings. Our results reveal that façade greening contributes only slightly to a reduction of heat stress in front of building façades.

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Albedo of Melting Sea Ice in the Southern Beaufort Sea

Journal of Glaciology ◽

10.3189/s0022143000013022 ◽

1971 ◽

Vol 10 (58) ◽

pp. 101-104 ◽

Cited By ~ 1

Author(s):

M.P. Langleben

Keyword(s):

Sea Ice ◽

Northwest Territories ◽

Beaufort Sea ◽

Ice Cover ◽

Short Wave ◽

Wave Radiation ◽

Short Wave Radiation ◽

Melting Period ◽

Fast Ice ◽

Made In

AbstractTwo Kipp hemispherical radiometers mounted back to back and suspended by an 18 m cable from a helicopter flying at an altitude of about 90 m were used to make measurements of incident and reflected short-wave radiation. The helicopter was brought to a hovering position at the instant of measurement to ensure that the radiometers were in the proper attitude and a photograph of the ice cover was taken at the same time. The observations were made in 1969 during 16 flights out of Tuktoyaktuk, Northwest Territories (lat. 69° 26’N., long. 133° 02’W.) over the fast ice extending 80 km north of Tuktoyaktuk. Values of albedo of the ice cover were found to decrease during the melting period according to the equation A = 0.59 —0.32P where P is the degree of puddling of the surface.

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