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Snowpack Software
RadTherm/RT provides realistic environmental loading inputs to the Swiss snowpack evolution model, SNOWPACK. SNOWPACK is the Swiss snowpack evolution model which is a plug-in to our RadTherm/RT software. This model attempts to simulate snowpack layering and characteristics such as density, temperature, and crystal type throughout the season using a set of relatively simple meteorological inputs. This model was developed by scientists from the Swiss Federal Institute for Snow and Avalanche Research (Michael Lehning and Perry Bartelt) with help from scientists from Montana State University (Bob Brown and Ed Adams)
How does RadTherm/RT work with Snowpack Software?
1. Weather conditions are measured using conventional meteorological equipment. Although this data could be utilized directly by SNOWPACK, it would not include the localized effects specific to the 3-d terrain (e.g., shadowing and reflections). Further, snow is nearly an infrared black-body and this enhances the importance of radiation exchanges.
2. RadTherm/RT solves the numeric model to incorporate the full effects of solar shadowing, multiple reflections, and re-radiation of geometric features. Each triangular element (or facet) of the terrain has a view factor to background, sky, and other elements. The total radiation on each element will be the net result of emitted radiant energy, incoming solar radiance, and incoming radiant energy (reflected or emitted from other elements).
3. The RadTherm/RT numerical solution is passed on to SNOWPACK as follows:
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Snowpack Inputs:
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Input Sources:
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| Shortwave Radiation |
RadTherm/RT calculates solar shadowing and multi-bounce reflections on the snow surface. |
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| Air Temperature |
Passed through RadTherm/RT from the user input through the TAI weather file. |
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| Snow depth or precipitation rates |
Passed through RadTherm/RT from the user input through the 3-d terrain model. |
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| Rel. humidity |
Passed through RadTherm/RT from the user input through the TAI weather file. |
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| Wind speed |
Passed through RadTherm/RT from the user input through the TAI weather file. |
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| Surface temperature, longwave radiation or cloudiness |
RadTherm/RT calculates loading based on cloud cover, multibounce reflections, and wind convection. |
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| Ground heat flux or ground temperature |
RadTherm/RT calculates a surface temperature based on the RadTherm/RT snow model. A user defined core temperature is also passed to SNOWPACK. |
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