NXD-2000

NXD-2000 is the Swiss nearest-neighbors program for local avalanche forecasting.   The nearest-neighbor technique was pioneered by Othmar Buser and his Swiss colleagues in the early-1980s.  The current operational program has been developed by Martin Gassner of the Swiss Federal Institute for Snow and Avalanche Research.  In essence, NXD2000 is a sophisticated method for searching through a large weather and avalanche database.  The model plots the weather data for the day of interest in a multidimensional space, and then calculates the days that are most similar to that day - the "nearest-neighbors".  Weather and avalanche data are displayed for the nearest-neighbors, helping the human forecaster to anticipate the avalanche problems they may encounter that day.  This provides an excellent avalanche forecasting tool for ski areas or highway avalanche forecasting operations.

In January of 2000, the Forest Service National Avalanche Center worked with Martin Gassner and Tom Leonard (then-Snow Safety Director) to install the program at Snowbasin Ski Area, venue for the 2002 Olympic Downhill and Super-G races.  SFISAR generously agreed to provide the program for free through the Olympics to demonstrate its usefulness for U.S. avalanche workers, and Snowbasin covered Martin's costs for coming to the U.S. to install the program.  Snowbasin used the program operationally from the 1999/2000 season through the 2002 Olympics and Mike Jenkins oversaw the use of the program after Tom's departure. Of course, if you watched the 2002 Olympics, you will realize that the weather was great for racing, with plenty of sunshine, but there were no significant avalanche problems.

Martin Gassner of the Swiss Federal Institute for Snow and Avalanche Research (right) trains Snowbasin Snow Safety personnel Tom Leonard (left) and Brandt Hart to use the avalanche forecasting program NXD2000

During the 2000/2001 season, Knox Williams and Andy Gleason of the Colorado Avalanche Information Center worked with Martin Gassner to install NXD2000 at Red Mountain Pass for their highway avalanche forecasting operation, and Bruce Tremper and Doug Wewer of the Utah Avalanche Center managed to get the program operational for the Utah Avalanche Center immediately prior to the 2002 Olympics.

Currently the model is seeing only limited use at its U.S. installations. Though it is a great tool, it requires a sizable time effort to get the data into the model and some operations feel that they cannot justify the extra time required to keep the model updated and running.