Mountain Meteorology
Mountains complement desert as desert
complements city, as wilderness complement
and completes civilization. Edward Abbey
Meteorology 5550
490 INSCC
TH 10:45 – 12:05
John Horel
Jim Steenburgh
Photo: J. Horel
Course Objectives and Content
Understand the influence of
the earth’s 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
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
Grading
 40%:
Homework, class participation, literature
reviews
 20%: Participation and writeup of results from
field experiment
 20%: 1st half quiz
 20% 2nd half quiz
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
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/?request=inde
x-html
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@met.utah.edu, Be prepared to discuss the reading
during that class.

Field Project
Analysis of wind circulations on skijump 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
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?)
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
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)

Effects of Mountains
Carruthers and Hunt 1990
Whiteman (2000)
http://infoplease.lycos.co
m/ipa/A0001792.html
Precipitation
Barry (1992)
Mountains
% mountains as fraction of total land surface (land 30%)
 0-1000 m
10%
 1000-2000 m 3%
 2000-3000 m 3%
 > 3000 m
4%
 Total
20%
Barry 1992
 %mountain as fraction of earth 6%

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.htm)
High Elevation Observatories
 Mt
Washington
 http://www.mountwashington.org/
 Storm
Peak Laboratory
 http://www.dri.edu/Projects/SPL/
Geographical controls of mountain
climate (Barry 1992)
 Latitude
 Continentality
 Altitude
 Topography
Jeff Klein. SLC BLM)
Jeff Klein. SLC BLM)
Thermally forced terrain circulations
 Mountain-valley
 Slope
winds
flows
 Peter Sinks Experiment
 VTMX
 lake breeze
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
Downslope Windstorms
 Conceptual
models
 Observations
 Numerical studies
 Gap winds
L. Darby & R. Banta, ATDD/ETL
Other subjects
 Orography
 Mountain
 Physiology
and the General Circulation
torque
of high altitude
 Climate change at high altitude
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 you’re 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 don’t leave
them with me)
 Due: whenever
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

Parameters used to define flow (Smith 1979)
Parameter
Symbol
Units
Typical Value
Mountain height
h
km
1
Width downstream
Lx
km
10
Width crossstream
Ly
km
100
Flow layer depth
H
km
1 PBL; 10 troposphere
Incoming windspeed
u
m/s
10
Incoming wind shear
uz
s-1
10-3
Stability frequency
N
s-1
10-2
Coriolis parameter
f
s-1
10-4
Buoyancy/reduced
gravity
b = d qg/q
m/s2
10-1