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Unformatted text preview: d over the past 50 years, leading
to higher surface water temperatures as well as at depth Higher sea temperatures stress tiny animals that make
up corals, leading to coral bleaching and death Fig. 4.9 Arctic summer sea ice Fig. 4.2 Northern snow cover Fig. 4.18 Greenland ice sheet
Fig. 4.15b, Glaciers Fig. 4.18 Antarctic ice sheet
UNIPCC AR4 WG1 Climate Trends
- Melting Ice
Glacier Glacier National Park, Montana Documenting Glacial Retreat and Loss As climate warms and drought becomes more
persistent, climate models predict by 2030 GNP loses
all of its glaciers.
Glaciers in place by 7,000 years ago; grew to maximum
during Little Ice Age ~ A.D. 1850.
150 glaciers in 20th century; in 2005 - 27 glaciers
Grinnell Glacier reduced by 90% area this past century.
Decline in ice tied to increase in mean summer
temperature and reduction in winter snowpack. Boulder Glacier
Glacier National Park, MT 1932 T. J. Hileman photo
courtesy of GNP archives 2005 USGS Repeat Photography Project
http://nrmsc.usgs.gov/repeatphoto/ Greg Pederson photo
USGS Grinnell Glacier
Glacier National Park, MT 1910 Fred Kiser photo
courtesy of GNP Archives 2008 USGS Repeat Photography Project
http://nrmsc.usgs.gov/repeatphoto/ Lisa McKeon photo,
USGS Grinnell Glacier
Glacier National Park, MT T.
1938 ourtesy J. Hileman photo
of GNP Archives 1981 Carl Key photo
USGS 1998 D. Fagre photo
USGS 2006 Karen Holzer photo
USGS Oblique view of Grinnell Glacier taken from the summit of Mount Gould, Glacier
The relative sensitivity of glaciers to climate change is illustrated by the dramatic recession
of Grinnell Glacier while surrounding vegetation patterns remain stable. USGS Repeat Photography Project
http://nrmsc.usgs.gov/repeatphoto/ Sperry Glacier
Park, MT 1930 circa Morton Elrod photo
K. Ross Toole Archives
Mansfield Library, UM 2008 Lisa McKeon photo,
USGS Repeating Elrod’s photograph from the same photo point was impossible since he shot
from the elevated perspective of the glacier’s surface. The terminus of the glacier has
retreated beyond the field of view, but these images give a sense of the glacier’s extent
and mass early in the 20th century. USGS Repeat Photography Project
http://nrmsc.usgs.gov/repeatphoto/ Melting Glaciers
According to a UN climate report, Himalayan
glaciers that are source...
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- Fall '13