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Geology topics

J. W. van Wagtendonk

Publications and source records attributed to J. W. van Wagtendonk.

47 records · Page 3Linked to original sources
USGS1984

Modeling behavior of prescribed fires in Yosemite National Park

The National Fire Danger Rating System and the Fire Behavior Prediction System were tested on prescribed fires burning underneath canopies in six fuel types in Yosemite National Park, California. The mean error for rate of spread was +0.03 foot per minute for the NFDRS and -0.15 foot for the FBPS. For flame length the mean error was -0.38 foot for both systems. Regressions provided factors for correcting predicted values. Burning prescriptions based on the models have been adjusted for the variation in their predictive capability.

Journal of Forestry↗
USGS1980

Wilderness permit compliance and validity

In Yosemite National Park, 92 percent of the parties using back country areas had permits. Parties without permits were smaller in size and stayed for shorter periods of time. For all parties with permits, 62 percent made changes to their trips. Parties changing their trips in both time and space accounted for 27 percent of the total, while 14 percent made temporal changes only, and 21 percent made spatial changes only. Use estimates can be adjusted by multiplying by 1 + C + Δ where C is the noncompliance factor and Δ is the change factor for compliers. While the combined effect of these factors on total visitor nights for the Yosemite backcountry was an overestimation of 12.5 percent, areas near trailheads received heavier use and outlying areas received lighter use than permits indicated.

Journal of Forestry↗