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Unit 6: Local and General Winds

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Wind Effects   ::   General Winds   ::   Local Winds   ::   Winds of Concern   ::   Wind Input   ::  Exercises

Exercise 1

Slope and Valley Winds

Using the map with points A-G, complete the following items relating to local winds in mountainous terrain under clear, warm, midsummer weather conditions.

Exercise 1

  1. Which slope (give point) will receive the early morning solar heat first, thus, upslope winds start first?
  2. Which slope (give point) will receive solar heating latest in the afternoon, thus, upslope winds continue the latest?
  3. Which slope (give point) will receive the least solar heating, thus, the lightest upslope winds throughout the day?
  4. Which slope (give point) will receive the least solar heating, thus, the lightest upslope winds throughout the day?
  5. When will point B receive the strongest downvalley winds?
  6. Which point will be most exposed to the general winds?
  7. What time of day will upslope winds be strongest at point A?
  8. What time of day will upslope winds be strongest at point C?
  9. Which direction will winds be at point F at 1500?
  10. At which two points will it be most difficult to predict wind directions?

Exercise 2

General and local winds

Match various winds with their definitions.

Wind Type Definition
1. Convective wind a. Small scale convective winds of local origin caused by temperature differences.
2. Foehn Wind b. All winds - up, down, or horizontal - that develop as a result of local temperature differences.
3. Frontal Wind c. Small scale convective winds that occur due to local heating and cooling of a natural incline of the ground.
4. General Wind d. The windspeed that affects a surface fire (roughly at eye level) that is used in the mathematical fire model.
5. Midflame Wind e. Winds caused by strong pressure gradients in the boundary area of two dissimilar air masses: characterized by shifting winds and increased velocities.
6. Surface Wind f. A dry wind with a stron down component, characteristic of mountainous region. It is usually, but not always, a warm wind for the season.
7. Local Wind g. Large scale winds caused by high and low pressure systems, but generally influenced and modified in the lower atmosphere by terrain.
8. Slope Wind h. The wind measured at the 20-foot level. It is often a combination of local and general winds.
Copyright 2008, Michael Jenkins. Cite/attribute Resource . admin. (2005, November 08). Unit 6: Local and General Winds. Retrieved January 07, 2011, from Free Online Course Materials — USU OpenCourseWare Web site: http://ocw.usu.edu/Forest__Range__and_Wildlife_Sciences/Wildland_Fire_Management_and_Planning/Unit_6__Local_and_General_Winds_12.html. This work is licensed under a Creative Commons License Creative Commons License