Hanzer, F.

Hynek, B.

Kunstmann, H.

Marke, T.

Olefs, M.

Sailer, R.

Schöner, W.

Strasser, U.

Stötter, J.

Warscher, M.

English

KITopen

KIT – University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz AssociationKarlsruhe Institute of Technology (KIT), Institute for Meteorology and Climate Research (IMK-IFU)www.kit.eduA terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainMichael Warscher, Thomas Marke, Florian Hanzer, Ulrich Strasser, Harald Kunstmann, Bernhard Hynek, Marc Olefs, Wolfgang Schöner, Rudolf Sailer, Johann Stötter Wien, 04.04.11 2Institute for Meteorology and Climate Research (IMK-IFU)Berchtesgaden National ParkMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainMunichInnsbruckSalzburg Wien, 04.04.11 3Institute for Meteorology and Climate Research (IMK-IFU)Surface and SubsurfcaceHydrology• Steep gradients• Complex hydrogeological situation• Karst, Subsurface pathways, Storage system “Alpine karst and its influence on the water balance at regional scale. “Kraller et al. (Poster Programme HS2.5, A 240,EGU2011-2229)Snow cover dynamics• Large amounts of snow, long period of snow coverage • Spatial and temporal variability of the snow cover• Precipitation storage during winter, runoff generation by melting snow• Snow „feeds“ glaciers and perennial firn fields• Lateral snow transport (wind, snow slides, avalanches)Regional HydrologyWien, 04.04.11 4Institute for Meteorology and Climate Research (IMK-IFU)Processes: 1. Preferential deposition of snow precipitation (before it has reached the ground)2. Wind-driven transport of previously fallen snow (erosion, saltation and accumulation)3. Effective sublimation of wind-blown snow into the atmosphereDepending on:Windspeed and direction, snow cover, shearstress, snow surface properties, snow density, humidity, temperature, radiation, … Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainSnow and windPlattner (2004)Wien, 04.04.11 5Institute for Meteorology and Climate Research (IMK-IFU)Snow and windMethodsBernhardt et al. (2009): Using wind fields from a high-resolution atmospheric model for simulating snow dynamics in mountainous terrainWinstral and Marks (2002): Simulating wind fields and snow redistribution usingterrain-based parameters to model snow accumulation and melt over a semi-arid mountain catchmentMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 6Institute for Meteorology and Climate Research (IMK-IFU)Snow and windApproach: modified, Winstral and Marks (2002)- Terrain-analysis to extract sheltered and exposed areas- Sheltered pixel accumulation of wind-blownsnow, more snow- Exposed pixel erosion of snow, less snow- Correction of snow precipitation in advance- Result represents the combination of all wind-driven snow effects (preferential deposition, erosion, saltation, suspension, accumulation, sublimation)Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 7Institute for Meteorology and Climate Research (IMK-IFU)Snow and windTerrain analysis• Extraction of a factor image fromthe digital elevation model (DEM)• Partial, directed sky view factor(SVFdir)Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 8Institute for Meteorology and Climate Research (IMK-IFU)Day-Degree Energy-Balance + SnowslidesSky view factorUniversity of Gothenburghttp://www.gvc2.gu.se/ngeo/urban/Activities/svf.htmespere, Wypych (nach Oke, 1987)http://www.atmosphere.mpg.de/enid/2__Stadtklima/-_Bestimmende_Faktoren_41q.htmlhttp://www.carltd.com/feature33.htmMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 9Institute for Meteorology and Climate Research (IMK-IFU)Snow and windTerrain analysis• Extraction of a factor image from the digital elevationmodel (DEM)• Partial, directed Sky View Factor (SVFdir)• Defininition of wind direction sector (e.g. SW, 180° -270 °)•  directed sky view factor SVFdirwindCorrField = E * (Depmax * (1 – SVFdir)  – 1) + 0.1whereE = (linear) elevation weighting factorSVFdir = directed sky view factorDepmax = maximum possible depositionMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 10Institute for Meteorology and Climate Research (IMK-IFU)Snow and windWind direction: SW No prevailing wind directionMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainWien, 04.04.11 11Institute for Meteorology and Climate Research (IMK-IFU)Snow and windParameterization (wind direction SW)BERNHARDT, M., ZÄNGL, G., LISTON, G. E., STRASSER, U. AND MAUSER, W. (2009): Using wind fields from a high-resolution atmospheric model for simulating snow dynamics in mountainous terrain. Hydrological Processes, 23: 1064–1075. doi: 10.1002/hyp.7208STRASSER, U. (2008): Modelling of the mountain snow cover in the Berchtesgaden National Park – Forschungsbericht 55. Nationalparkverwaltung Berchtesgaden (Hrsg.). Berchtesgaden.Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainCoupled atmospheric / snow transport modelWien, 04.04.11 12Institute for Meteorology and Climate Research (IMK-IFU)Snow and windParameterization (wind direction SW)Coupled atmospheric / snow transport modelMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrain Similar spatial patternsBERNHARDT, M., ZÄNGL, G., LISTON, G. E., STRASSER, U. AND MAUSER, W. (2009): Using wind fields from a high-resolution atmospheric model for simulating snow dynamics in mountainous terrain. Hydrological Processes, 23: 1064–1075. doi: 10.1002/hyp.7208STRASSER, U. (2008): Modelling of the mountain snow cover in the Berchtesgaden National Park – Forschungsbericht 55. Nationalparkverwaltung Berchtesgaden (Hrsg.). Berchtesgaden.Wien, 04.04.11 13Institute for Meteorology and Climate Research (IMK-IFU)Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainLandsat RGB ETM+ 01.05.2005NDSI (not showing negative values)01.05.2005Modelled mean snow cover duration 2002 – 2007Wien, 04.04.11 14Institute for Meteorology and Climate Research (IMK-IFU)Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainLandsat RGB ETM+ 01.05.2005NDSI (not showing negative values)01.05.2005Modelled mean snow cover duration 2002 – 2007Landsat ETM+ Model (WaSiM-ETH + AMUNDSEN)  Wien, 04.04.11 15Institute for Meteorology and Climate Research (IMK-IFU)Day-DegreeNash-Sutcliffe = 0.52Snow melt and runoff dynamicsRunoff at gauge Hintersee (melting period spring 2006)E-Bal + SnowslidesNash-Sutcliffe = 0.69E-Bal + Snowslides + WindNash-Sutcliffe = 0.76Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainDo we need that within hydrological LSMs?Snow module:Wien, 04.04.11 16Institute for Meteorology and Climate Research (IMK-IFU)Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainOverall model performance: Mean Nash-Sutcliffe coefficient at the gauges (Nov. 2002 – Okt. 2007) with different snow model approaches and different assumed main wind direction sectorsSnow model and water balanceDo we need that within hydrological LSMs?Wien, 04.04.11 17Institute for Meteorology and Climate Research (IMK-IFU)Next stepsDay-Degree Energy-Balance + SnowslidesMichael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrainChanges in heightMay 2003 minus September 2002HintereisfernerMay 2009 minus September 2008Airborne Laserscanning dataWien, 04.04.11 18Institute for Meteorology and Climate Research (IMK-IFU)Thanks!Michael Warscher - A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrain

A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrain

https://publikationen.bibliothek.kit.edu/230085932/3815969

A terrain-based parameterization for the effect of wind-induced snow transport in Alpine terrain

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