Mountain Meteorology

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Mountain Meteorology
Mountains complement desert as desert complements
city, as wilderness complements and completes
civilization. Edward Abbey

• Meteorology 5550
• 490 INSCC
• TH 1045 1205
• John Horel
• Jim Steenburgh

Photo J. Horel
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Course Objectives and Content

• Understand the influence of the earths orography
  upon weather and climate
• First Half- John Horel
• Geographical controls of mountain weather and
  climate
• Terrain-forced flows
• Flow interaction with complex terrain

Photo J. Horel
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Course Content (cont.)

• Second half- Jim Steenburgh
• Orographically modified cyclones
• Orographically trapped disturbances
• Orographic precipitation
• Invited presentations
• Fire weather
• Air quality
• Avalanches
• Surface transportation

Houze 1993
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Grading

• 40 Homework, class participation, literature
  reviews
• 20 Participation and writeup of results from
  field experiment
• 20 1st half quiz
• 20 2nd half quiz

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Source Material

• Mountain Meteorology. D. Whiteman. 2000.
• Mountain Weather and Climate. R Barry. 1992.
• Atmospheric Processes over Complex Terrain. W.
  Blumen 1990.
• Influence of Mountains on the Atmosphere. R.
  Smith. 1979. Advances in Geophysics. 21.
• Additional Reading

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Reading Assignments

• Many available on-line. To save trees, you are to
  access them on-line from campus and print them as
  needed
• http//ams.allenpress.com/amsonline/?requestindex
  -html

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First Reading Assignment

• First reading assignment Barry, R. G. (1978)
  H. B. de Saussure the first mountain
  meteorologist. Bull. Amer. Meteor. Soc., 59,
  702-5.
• Summarize in a few paragraphs (1) who Saussure
  was (2) how did he make the measurements and
  what were his results regarding the decrease of
  temperature with height (3) what other
  contributions to mountain meteorology did he
  make?
• Due via email at beginning of class on Aug. 30.
  Send to jhorel_at_met.utah.edu, Be prepared to
  discuss the reading during that class.

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Field Project

• Analysis of wind circulations on ski-jump slope
• Weather permitting
• Set up on Friday September 28
• Observations Saturday morning September 29
• Takedown in afternoon
• Requires planning in advance by class to design
  useful field project
• Requires analysis of data after data collection
  completed

Photo J. Horel
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VTMX Workshop

• September 10-12
• Useful presentations on local wind circulations
  in Salt Lake Valley
• Plan on attending a few hours at some point
  instead of class on the 11th (and 13th?)

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What is a mountain?

• Common usage
• 600 m or more of local relief defines a mountain
• Less than 600m is a hill
• High mountain/alpine areas (Troll 1973 Arct.
  Alp. Res., 5, 19-27)
• Relative to terrain features
• Upper timberline
• Snow line

Himalayas Photo credit NASA/Science Photo
Library
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What are the effects of mountains?

• Substantial modification of synoptic or meso
  scale weather systems by dynamical and
  thermodynamical processes through a considerable
  depth of the atmosphere
• Recurrent generation of distinctive wx
  conditions, involving dynamically and thermally
  induced wind systems, cloudiness, and
  precipitation regimes
• Slope and aspect variations on scales of 10-100 m
  form mosaic of local climates
• (Barry 1992)

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Effects of Mountains
Carruthers and Hunt 1990
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Whiteman (2000)
http//infoplease.lycos.com/ipa/A0001792.html
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Precipitation
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Barry 1992
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Barry (1992)
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Mountains

• mountains as fraction of total land surface
  (land 30)
• 0-1000 m 10
• 1000-2000 m 3
• 2000-3000 m 3
• gt 3000 m 4
• Total 20
• Barry 1992
• mountain as fraction of earth 6

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Mt. Everest

• http//www.mteverest.com/
• http//www.mnteverest.net/
• http//www.m.chiba-u.ac.jp/class/respir/eve_e.htm
• http//www.newton.mec.edu/Angier/DimSum/Him.Range
  Pix.html
• Height of Mt. Everest 8848m
• (http//www.m.chiba-u.ac.jp/class/respir/hyoko_e.h
  tm)

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High Elevation Observatories

• Mt Washington
• http//www.mountwashington.org/
• Storm Peak Laboratory
• http//www.dri.edu/Projects/SPL/

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Geographical controls of mountain climate (Barry
1992)

• Latitude
• Continentality
• Altitude
• Topography

Jeff Klein. SLC BLM)
Jeff Klein. SLC BLM)
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Thermally forced terrain circulations

• Mountain-valley winds
• Slope flows
• Peter Sinks Experiment
• VTMX
• lake breeze

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Flow Interaction With Complex Terrain

• Buoyancy oscillations
• Flow over vs. around obstacles
• Kinetic and potential energy of flows
• Mountain waves
• Gravity wave drag
• Trapped lee waves

Photo J. Horel
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Downslope Windstorms

• Conceptual models
• Observations
• Numerical studies
• Gap winds

L. Darby R. Banta, ATDD/ETL
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Other subjects

• Orography and the General Circulation
• Mountain torque
• Physiology of high altitude
• Climate change at high altitude

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1st Homework Assignment

• Bring in a couple (to as many as you want) of
  mountain and mountain weather related photos
• Be prepared to say a few words about 1-2 photos
• If youre willing to allow use of the photos for
  this class and future classes, scan the images on
  the PC in Rm 480 (details to be provided, but
  dont leave them with me)
• Due whenever

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Homework Assignment 2

• (1) Find 5 interesting and useful internet web
  pages related to mountain weather, mountain
  climates, or alpine environments
• (2) Send me in 1 email the web addresses with a
  1-2 sentence description of the content of each
  page
• (3) Provide at least 2 scientific, literary, or
  artistic (music/art) definitions or descriptions
  of mountains. Not from dictionaries
• (4) Provide a reference/source for that
  definition and send it in the same email as that
  used above
• Due August 30

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Parameters used to define flow (Smith 1979)