Mountain Weather and Climate

Meteorology 3000

490 INSCC

MWF 9:40-10:30

John Horel

Course Objective

Understand the influence of the earth’s orography upon weather and climate

Apply understanding of mountain weather and climate to human activities (safety, health, sport, fire, road)

Course Outline

1. Overview. Mountain Climates

2: Vertical structure; stability. Thermals and Personal Flying Craft

3: Boundary layer and surface energy budget. The VTMX and Peter Sinks Experiments.

4: Pressure, Winds. Large-scale Mountain Effects.

5: Fronts. Evolution of Intermountain Storms.

6: Clouds. Understanding Weather Changes by Watching Clouds.

7: Precipitation. Orographic storms and Great Salt Lake effect snowstorms.

Course Outline (cont.)

8: Terrain-forced flows. Utah Canyon Wind storms.

9: Diurnal Mountain Winds. Local drainage circulations.

10: Air Pollution. Air Quality in the Salt Lake Basin.

11: Fire Weather.

12: Physiological Effects of High Altitude.

13: Snowpack. Physics of skiing

14: Avalanches.

15: Mountain Road Weather.

16: Review

Grading

45%: Homework and assignments, class participation,

30%: 3 quizzes

25%: final

Reading Assignments

Roughly 1 chapter per week (1 article per week in the later weeks)

It is required that you finish the reading assignment PRIOR to the lectures and in-class assignments on the reading material

Be prepared to discuss material in reading assignment

Homework Assignment #0

Bring in a couple (to as many as you want) of mountain and mountain weather related photos OR even better, send them to me as email

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, I will scan the images and return them to you

Write your name on the back of each photo

Due: Any time during the semester. Can be done multiple times for extra credit

Field Day

First choice- Saturday October 12

Second choice- Saturday October 19

Weather permitting

Monitor atmospheric conditions at Snowbird

Requires planning in advance by class to design useful field project

Requires analysis of data after data collection completed

Slide 9

Slide 10

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

Slide 12

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

Distribution of mountains on the globe

Mountains

% mountains as fraction of total land surface

0-1000 m       10%

1000-2000 m   3%

2000-3000 m   3%

> 3000 m         4%

Total               20%

Barry 1992

Highest 10 mountains in the world

The Himalayas

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%20Pix.html

Height of Mt. Everest: 8848m

(http://www.m.chiba-u.ac.jp/class/respir/hyoko_e.htm)

Mountains

Highest Peaks By Continent

Alps

Mountains in North America

U.S. Peaks

Appalachian Mountains

Mountains of the western US

High Elevation Observatories

Mt Washington

http://www.mountwashington.org/

Storm Peak Laboratory

http://www.dri.edu/Projects/SPL/

Utah

Homework Assignment #1

(1) Find 3 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 paragraph description of the content of each page

(3) Provide at least 2 scientific, literary, or artistic (music/art) definitions of a mountain. Not from dictionaries

(4) Provide a reference/source for that definition and send it in the same email as that used above

Due August 28

Slide 30

Slide 31

"Existence on a mountain is..."

Existence on a mountain is simple. Seldom in life does it come any simpler: survival, plus striving toward the summit. The goal is solidly three-dimensionally there- you can see it, touch it, stand upon it – the way to reach it well defined, the energy of all directed toward its achievement. It is this simplicity that strips the veneer of civilization and makes that which is meaningful easier to come by – the pleasure of deep companionship, moments of uninhibited humor, the tasting of hardship, sorrow, beauty, joy. But it is this very simplicity that may prevent finding answers to the questions I have asked as we approached the mountains.” ~ Tom Hornbein, Everest: The West Ridge Source: Willis, C. (ed.), 1997. Epic: Stories of Survival from the World’s Highest Peak; pg. 220.

Slide 33

"The Storm Testament (Ch..."

The Storm Testament (Ch 21, 2nd paragraph)
Beaver George and I were riding up a little valley, scattered ponderosa pine on either side and willows, alder and aspen in the bottom where the small stream wound its way from beaver pond to beaver pond. It was a winding valley, and we couldn't see very far ahead. It was early afternoon; the deep blue of the Rocky Mountain Shy made a sharp contrast to the scattered puffy white clouds. The sun was warm, but not uncomfortable, thanks to a fresh breeze coming gently down from the mountains ahead of us.

Slide 35

"My father considered a walk..."

My father considered a walk among the mountains as the equivalent of churchgoing. - Aldous Huxley

Slide 37

""Enjoy the mountains;"

"Enjoy the mountains; they have beauty and wisdom for us if we approach them with humility, respect, and knowledge." -Charles Houston

Slide 39

"Mountains and uplands may defined..."

Mountains and uplands may defined as features of the Earth's surface in which the terrain projects conspicuously above its surroundings, and where the slope of the land distinguishes it from the generally flat plains."
Beniston, Martin. Environmental Change in Mountains and Uplands. New York: Oxford University Press, 2000, p. 1.

Slide 41

Slide 42

Four main climate factors

Climate differs from one location to another because of:

Latitude

Altitude

Continentality

Exposure to regional circulations, including winds and ocean currents

Latitude

Determines length of day and angle of incoming sunlight and, thus, amount of solar radiation received

In equatorial regions, day length & solar angle change little with season. Little seasonal variability, mostly diurnal changes.

In polar regions, the sun does not rise at all in winter. In the summer it never sets, although remaining low in sky. Big seasonal changes, small diurnal changes.

In mid-latitudes, seasonal and diurnal changes.

Also determines site’s exposure to latitudinal belts of high and low pressure

High pressure - subsidence

Low pressure - convection

Altitude

Solar radiation increases with altitude

Changes in air temperature at high altitudes are small, however, because of smaller amount of land area at higher altitudes

Air temperature usually decreases with altitude (-6.5°C/km)

Moisture in air usually decreases with altitude

Wind speed usually increases with altitude

Air density and atmospheric pressure decrease exponentially with altitude

Continentality

Continental locations experience larger diurnal and seasonal temperature changes than locations on or near large bodies of water because land surfaces heat and cool more quickly than oceans.

Interior locations experience more sunshine, less cloudiness, less moisture and less precipitation than coastal areas.

Precipitation is especially heavy on the windward side of coastal mountain ranges oriented perpendicular to prevailing winds from the ocean. Marine air lifted up a mountain range releases much of its moisture as precipitation. As a result, far less precipitation is received on the leeward side.

Regional circulations

Latitude, altitude and continentality are the primary factors, but exposure to regional winds and ocean currents is also a factor

Some regional winds are associated with the latitudinal bands of high and low pressure (e.g., Pacific High, Aleutian low, Bermuda-Azores high)

Ocean currents also play an important role. Ex: Gulf Stream in Atlantic and Japanese Current in Pacific affect North America.


	Understand the influence of the earth’s orography upon weather and climate
	Apply understanding of mountain weather and climate to human activities (safety, health, sport, fire, road)


	1. Overview. Mountain Climates
	2: Vertical structure; stability. Thermals and Personal Flying Craft
	3: Boundary layer and surface energy budget. The VTMX and Peter Sinks Experiments.
	4: Pressure, Winds. Large-scale Mountain Effects.
	5: Fronts. Evolution of Intermountain Storms.
	6: Clouds. Understanding Weather Changes by Watching Clouds.
	7: Precipitation. Orographic storms and Great Salt Lake effect snowstorms.


	8: Terrain-forced flows. Utah Canyon Wind storms.
	9: Diurnal Mountain Winds. Local drainage circulations.
	10: Air Pollution. Air Quality in the Salt Lake Basin.
	11: Fire Weather.
	12: Physiological Effects of High Altitude.
	13: Snowpack. Physics of skiing
	14: Avalanches.
	15: Mountain Road Weather.
	16: Review


	45%: Homework and assignments, class participation,
	30%: 3 quizzes
	25%: final


	Roughly 1 chapter per week (1 article per week in the later weeks)
	It is required that you finish the reading assignment PRIOR to the lectures and in-class assignments on the reading material
	Be prepared to discuss material in reading assignment


	Bring in a couple (to as many as you want) of mountain and mountain weather related photos OR even better, send them to me as email
	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, I will scan the images and return them to you
	Write your name on the back of each photo
	Due: Any time during the semester. Can be done multiple times for extra credit


	First choice- Saturday October 12
	Second choice- Saturday October 19
	Weather permitting
	Monitor atmospheric conditions at Snowbird
	Requires planning in advance by class to design useful field project
	Requires analysis of data after data collection completed


	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


	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)


	% mountains as fraction of total land surface
	0-1000 m 10%
	1000-2000 m 3%
	2000-3000 m 3%
	> 3000 m 4%
	Total 20%

	Barry 1992


	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%20Pix.html
	Height of Mt. Everest: 8848m
	(http://www.m.chiba-u.ac.jp/class/respir/hyoko_e.htm)


	Mt Washington
		http://www.mountwashington.org/

	Storm Peak Laboratory
		http://www.dri.edu/Projects/SPL/


	(1) Find 3 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 paragraph description of the content of each page
	(3) Provide at least 2 scientific, literary, or artistic (music/art) definitions of a mountain. Not from dictionaries
	(4) Provide a reference/source for that definition and send it in the same email as that used above
	Due August 28


	Existence on a mountain is simple. Seldom in life does it come any simpler: survival, plus striving toward the summit. The goal is solidly three-dimensionally there- you can see it, touch it, stand upon it – the way to reach it well defined, the energy of all directed toward its achievement. It is this simplicity that strips the veneer of civilization and makes that which is meaningful easier to come by – the pleasure of deep companionship, moments of uninhibited humor, the tasting of hardship, sorrow, beauty, joy. But it is this very simplicity that may prevent finding answers to the questions I have asked as we approached the mountains.” ~ Tom Hornbein, Everest: The West Ridge Source: Willis, C. (ed.), 1997. Epic: Stories of Survival from the World’s Highest Peak; pg. 220.


	My father considered a walk among the mountains as the equivalent of churchgoing. - Aldous Huxley


	"Enjoy the mountains; they have beauty and wisdom for us if we approach them with humility, respect, and knowledge." -Charles Houston


	Mountains and uplands may defined as features of the Earth's surface in which the terrain projects conspicuously above its surroundings, and where the slope of the land distinguishes it from the generally flat plains." Beniston, Martin. Environmental Change in Mountains and Uplands. New York: Oxford University Press, 2000, p. 1.


	Climate differs from one location to another because of:

	Latitude

	Altitude

	Continentality

	Exposure to regional circulations, including winds and ocean currents


	Determines length of day and angle of incoming sunlight and, thus, amount of solar radiation received
		In equatorial regions, day length & solar angle change little with season. Little seasonal variability, mostly diurnal changes.
		In polar regions, the sun does not rise at all in winter. In the summer it never sets, although remaining low in sky. Big seasonal changes, small diurnal changes.
		In mid-latitudes, seasonal and diurnal changes.

	Also determines site’s exposure to latitudinal belts of high and low pressure
		High pressure - subsidence
		Low pressure - convection


	Solar radiation increases with altitude
		Changes in air temperature at high altitudes are small, however, because of smaller amount of land area at higher altitudes

	Air temperature usually decreases with altitude (-6.5°C/km)

	Moisture in air usually decreases with altitude

	Wind speed usually increases with altitude

	Air density and atmospheric pressure decrease exponentially with altitude


	Continental locations experience larger diurnal and seasonal temperature changes than locations on or near large bodies of water because land surfaces heat and cool more quickly than oceans.
	Interior locations experience more sunshine, less cloudiness, less moisture and less precipitation than coastal areas.
	Precipitation is especially heavy on the windward side of coastal mountain ranges oriented perpendicular to prevailing winds from the ocean. Marine air lifted up a mountain range releases much of its moisture as precipitation. As a result, far less precipitation is received on the leeward side.


	Latitude, altitude and continentality are the primary factors, but exposure to regional winds and ocean currents is also a factor
	Some regional winds are associated with the latitudinal bands of high and low pressure (e.g., Pacific High, Aleutian low, Bermuda-Azores high)
	Ocean currents also play an important role. Ex: Gulf Stream in Atlantic and Japanese Current in Pacific affect North America.