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.

1. Glacier Change and its Effects on
Alpine Runoff in the American West
Lilliput Glacier
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

2. Glaciers in the American West
1 : 24,000
1158 8303 perennial snow
3079
68.6 and ice features
450
688 km2
(266 miles2)
463
42.5
208
2.6 1475
73.3
1
0.09 141
4.8
1778
46.2
US Forest Service lands
National Park Service lands
Glaciers

3. Beartooth, MT
Wind River, WY
Lewis CO
Range, MT
North
Cascades
Sierra
Nevada

4. Distribution of Glacier Area
1958-1980
3000
2500
2000
Number
Lyell Glacier, east lobe, Basagic, 2006
1500
1000
500
0
2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5
Area (m)
Log Area (m2)
South Cascade Glacier, 1960

6. 1907
Darwin Glacier
Sierra Nevada
Kings Canyon Nat. Park
August 14, 1907
G.K.Gilbert
2003
August 2, 2003
Hassan Basagic

7. Fraction of Glacier Area Lost since 1900
25%
31% 46% 66%
24%
30%
40%
56%
US Forest Service lands
National Park Service lands
Glaciers

8. Fraction of Glacier Area Lost since 1900
25%
31% 46% 66%
24%
30%
South Cascade Glacier, Fountain, 1984
40%
56%
US Forest Service lands
National Park Service lands
Glaciers

9. Glacier Change Across the Change in Glacier National Park Glaciers
Area
West
4
Glacier
3
Area (km 2)
Grinell
2
Sperry
1
0 Area Change in Olympic Range Glaciers
1900 1910 1920 1930 1940 1950 1960 1970 1980
6 Year
5 Blue
4 Anderson
Area (km 2)
Constance
3
Olympic Eel
2 Mystery
1 Hoh
0 Area Change in RMNP
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
0.12 Year
0.1 Andrew s
Area (km 2)
0.08
Tyndall
0.06
Sprague
0.04
0.02 Row e
0
Rocky Mtn Change in Sierra Nevada Glaciers
Area
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
0.7 Year
Conness
0.6
0.5
Yoseki Lyell West
Area (km 2)
Lyell East
0.4
Darw in
0.3
Goodard
0.2
Picket
0.1
Lilliput
0
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Year

10. Climate Controls
on Glacier Change
Loading:
Locations of glaciers with long time series
PC1: 47%
PC2: 18%

11. Effects on Water Quality
Electrical Conductivity
Water Temperature
Applies to point source variables
Does not apply to turbidity or suspended sediment

12. North Cascades, Washington
Vancouver
Seattle
Portland
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

13. Hypothesized Changes in Water Quality
Thunder Creek Basin
1900 2006
glaciers

14. Precipitation and Runoff in Thunder Creek Basin
1950 1960 1970 1980 1990 2000 2010
30
cm per month
cm per month
cm per month
Aug- Sep
Aug- Sep
per month cm permonth
20
cmcmpermonth cm per month
Precipitation
Precipitation
10
0 Aug- Sep
Aug- Sep
20 Runoff
Runoff
-10
cmper month
cm per month 10
-20
0
-10
Aug- Sep
Aug- Sep
-20 Runoff - Precip
Runoff - Precip
Cummulative mass balance
21950 1960 1970 1980 1990 2000 2010
mass balance (m weq)
5
1 0
-5
(m weq)
0
-10
-1
-15
-2 South CascadeGlacier
South Cascade Glacier
-20
-3 -25
Klawatti Glacier Thunder Creek Basin 1950 1960 1970 1980 1990 2000 2010

15. Importance of Glaciers in the Pacific Northwest
Water Supply
Jeff Phillippe, 2008

16. Effects: Hazards
Geologic Hazards
debris flows
outburst floods
John Scurlock
Oregon Highway 35, Nov 7, 2006 Doug Jones

17. 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.