Instuctor: Mark Williams
Telephone: 492-4794 or 492-8830


Primary approaches to modeling snowmelt are:

  1. ablation stakes
  2. regression analysis (linear or multiple)
  3. temperature index approach
  4. energy balance approach


Ablation stakes were the first approach consistently used to model distributed snowmelt over some area of interest. Ablation stakes are still widely used in glacial hydrology. Essentially, stakes are placed in the snow and the distance between the snow surface and top of the stake is noted. The readings are repeated at some temperal frequency, usually weekly to monthly. The difference in depth between two readings is the amount of snow depth lost over that time interval. Density is measured or estimated as well. Depth times the depth change provides SWE contribution to snow melt. There may be an adjustment factor (guesstimate) for losses to sublimation/ET.



Based on the concept that changes in air temperature provide an index of snowmelt. Air temperature is a commonly measured meterological variable, so a good choice from the standpoint of data availability. Moreover, air temperature is a secondary meteorological variable that provides an integrated measure of heat energy, so a good choice from that standpoint as well.


Snowmelt Runoff Model (SRM) developed by Martinec and Rango


These models can be run at a point or be spatially distributed. Essentially, these models run on measured data and transfer that information based on first principles. This is in contrast to empirical models such as SRM, which run on only a few measured parameters and which rely on calibration parameters at the heart of the model. However, with energy balance models you sacrifice simplicity for complicated measurements and complicated algorithms. Your energy balance model is only as good as your measured data and your understanding of the system.

Energy balance models are often run at a point with measured meteorological variables. These point measurements are then spatially distributed using a variety of simplifying assumptions.

Important factors:

General Modeling Approach. Each is usually a stand-alone submodel.

  1. Precipitation submodel
  2. Energy balance submodel
  3. Snowpack Model
  4. Snow Depletion Model