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Variations in glacier retreat in the American West, implications for water resources. Presented by Andrew Fountain at the "Perth II: Global Change and the World's Mountains" conference in Perth, Scotland in September 2010.
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Glacier Change and its Effects on
Alpine Runoff in the American West
Global Change and the World’s Mountains Perth September 28, 2010
Andrew G. Fountain1, Kristina Thorneycroft1, David Peterson2, and Dan Fagre3
1Portland State University, Portland, OR; 2US Forest Service, Seattle, WA; 3US Geological Survey, West Glacier, MT
Lilliput Glacier
US Forest Service lands National Park Service lands Glaciers
Glaciers in the American West 1 : 24,000
8303 perennial snow and ice features
688 km2 (266 miles2)
3079
141
1
1475
1778
1158
463
450
4.8
73.3
68.6
46.2
42.5
0.09
208 2.6
North Cascades
Sierra Nevada
Lewis Range, MT
Beartooth, MT Wind River, WY
CO
South Cascade Glacier, 1960
0
500
1000
1500
2000
2500
3000
Area (m)
Nu
mb
er
2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5
Log Area (m2)
Distribution of Glacier Area 1958-1980
Lyell Glacier, east lobe, Basagic, 2006
August 14, 1907
August 2, 2003
G.K.Gilbert
Hassan Basagic
1907
2003
Darwin Glacier
Sierra Nevada
Kings Canyon Nat. Park
US Forest Service lands National Park Service lands Glaciers
66%
24%
30%
56%
40%
31%
Fraction of Glacier Area Lost since 1900
25%
46%
US Forest Service lands National Park Service lands Glaciers
66%
24%
30%
56%
40%
31%
Fraction of Glacier Area Lost since 1900
25%
46%
South Cascade Glacier, Fountain, 1984 South Cascade Glacier, Fountain, 1984
Area Change in Sierra Nevada Glaciers
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Year
Are
a (
km
2)
Conness
Lyell West
Lyell East
Darw in
Goodard
Picket
Lilliput
Area Change in RMNP
0
0.02
0.04
0.06
0.08
0.1
0.12
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Year
Are
a (
km
2) Andrew s
Tyndall
Sprague
Row e
Area Change in Olympic Range Glaciers
0
1
2
3
4
5
6
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Year
Are
a (
km
2)
Blue
Anderson
Constance
Eel
Mystery
Hoh
Area Change in Glacier National Park Glaciers
0
1
2
3
4
1900 1910 1920 1930 1940 1950 1960 1970 1980
Year
Are
a (
km
2)
Grinell
Sperry
Glacier Change Across the West Glacier
Olympic
Rocky Mtn
Yoseki
Climate Controls
on Glacier Change
Locations of glaciers with long time series
Loading:
PC1: 47%
PC2: 18%
Effects on Water Quality Electrical Conductivity
Water Temperature
Applies to point source variables
Does not apply to turbidity or suspended sediment
Area (km2) % Basin Coverage
1900 63.04 23.18%
1958 37.16 13.67%
1998 35.67 13.12%
2006 32.8 12.06%
Thunder Creek Basin Area: 271.9 km2
Mean Basin Elevation: 1768 m
Vancouver
Seattle
Portland
North Cascades, Washington
1900 2006
Hypothesized Changes in Water Quality Thunder Creek Basin
glaciers
-20
-10
0
10
20
30
1950 1960 1970 1980 1990 2000 2010
cm p
er
mo
nth
-3
-2
-1
0
1
2
1950 1960 1970 1980 1990 2000 2010
mas
s b
alan
ce (
m w
eq
)
-25
-20
-15
-10
-5
0
5
Cu
mm
ula
tive
mas
s b
alan
ce
(m w
eq
)
-20
-10
0
10
20
1950 1960 1970 1980 1990 2000 2010
cm
per
mo
nth
c
m p
er
mo
nth
cm
per
mo
nth
cm
per
mo
nth
Aug- Sep
Precipitation
Aug- Sep
Runoff
Aug- Sep
Runoff - Precip
South Cascade Glacier
-20
-10
0
10
20
30
1950 1960 1970 1980 1990 2000 2010
cm p
er
mo
nth
-3
-2
-1
0
1
2
1950 1960 1970 1980 1990 2000 2010
mas
s b
alan
ce (
m w
eq
)
-25
-20
-15
-10
-5
0
5
Cu
mm
ula
tive
mas
s b
alan
ce
(m w
eq
)
-20
-10
0
10
20
1950 1960 1970 1980 1990 2000 2010
cm
pe
r m
on
th
cm
pe
r m
on
th
cm
per
mo
nth
c
m p
er
mo
nth
Aug- Sep
Precipitation
Aug- Sep
Runoff
Aug- Sep
Runoff - Precip
South Cascade Glacier
Precipitation and Runoff in Thunder Creek Basin
Klawatti Glacier Thunder Creek Basin
Importance of Glaciers in the Pacific Northwest
Water Supply
Jeff Phillippe, 2008
Geologic Hazards debris flows outburst floods
Oregon Highway 35, Nov 7, 2006 Doug Jones
John Scurlock
Effects: Hazards
Conclusions
• Glacier recession, like elsewhere in the world has been substantial in the American West. The main driver of glacier shrinkage is warming air temperatures. • Glacier recession has probably affected water quality in terms of warmer stream temperatures and higher electrical conductivity. • Mass wastage of glaciers have contributed to stream flow in measurable ways and if glaciers continue to recede the water runoff will be substantially reduced. • In regions populated with stratovolcanoes, glacier recession will increase the potential of slope failures and resulting debris flows.
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