Transcript Melting Mountains - Columbia University

Melting Mountains
Are retreating equatorial East African glaciers indicative of larger global warming trends?
What are the effects of this retreat?
By Andrew Morris, Will Snider,
and Dillon Stern
Introduction
 Statement of Objectives
 Global warming? Long-term climate
change?
 Methodology
 Air temperature vs. precipitation
Evidence
 Maps of ice extent
atop Kibo in 1912,
1953, 1976, 2000
 12km2 --> 2.6km2
 80% decrease
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Hasenrath et al, 1997
Causes - Air Temperature
 Using lake levels to rule out significance
of precipitation
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Causes - Air Temperature
(cont’d)
 Ice core samples
from Kilimanjaro
 Dust levels proxy for
precipitation
 Historically, the
glaciers survived a
300-year drought
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Causes - Precipitation
 Precipitation is particularly
important because snowfall
governs energy exchanges
on the flat, dark volcanic
sand adjacent to the vertical
ice walls (Hardy, 2007).
These vertical walls
accounts for much of the
continuous decrease in areal
extent of the glaciers
 A minimum monthly snowfall
of ~10cm is needed to
prevent glacial melting
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Hardy, 2007
Impact
 Water
 No significant effect on
water supply
 Tourism?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Conclusion
 No clear evidence that East African
glacial recession is evidence of global
warming
 Future research