World View of Global Warming
THE PHOTOGRAPHIC DOCUMENTATION OF CLIMATE CHANGE
Copyright © 2005 - 2008
3. (continued) Ice under fire, rising seas: Geophysical changes
Research Papers and Documents
For information on the Larsen ice shelf breakup of 2002, see National
Snow and Ice Data Center, http://nsidc.org/iceshelves/larsenb2002/.
Glaciologist Ted Scambos' studies of this and other shelves "provide
a solid link between climate warming and the recent extensive disintegration..."
(article 16 January 2001 on this site).
Eugene Domack, et al. "Antarctic Peninsula Climate Variability:
A Historical and Paleoenvironmental Perspective"
A conference sponsored by the National Science Foundation April 2002,
Hamilton College New York. Abstracts available at; http://academics.hamilton.edu/workshops/antarctica/Abstracts/
See also Domack et al, Cruise Reveals History of Holocene Larsen Ice
Shelf. EOS (American Geophysical Union) Vol. 82/2 pg 13-17 (2001)
Serreze, M.C. et al. (includes Chapin and Osterkamp) "Observational
Evidence of Recent Change in the Northern High-Latitude Environment"
Climatic Change 4:159-207 (2000)
Reports up to 6° C increase in winter temps since 1966 in large
areas of Siberia and North America, lesser amount in summer, but the
warming in winter can slowly increase temp of permafrost, making it
easier to thaw into the active layer. Also snow depth may increase.
See also Overpeck, J., K. et al. "Arctic environmental
change of the last four centuries"<italic> Science</italic>,
278, pg 1251 (1997).
Rothrock et al., "Thinning of the arctic sea-ice cover"
Geophysical Research Letters, Vol. 26, pg 3469 ; and Vinnikov et al.,
"Global warming and northern hemisphere sea ice extent" Science,
Vol. 286, pg 1934 (1999)
Data from satellites show that perennial ice (ice that survives all
year) declined by 14 per-cent between 1978 and 1998, while data from
submarine cruises show that ice thickness has declined by about 40 percent
over the last 20-40 years. A related study estimated only a slight chance
that the observed trends were due to natural variability, suggesting
that human activities probably contribute to the loss of Arctic sea
ice
Another measure of Arctic Sea Ice was created from satellite microwave
data from 1978 to 2000, by Josefino Cosimo et al in Geophys.
Res. Letters 29, pg 1956 (2002). The area covered by the ice has
decreased at a rate of 9% per decade, and at this rate will disappear
later in the present century. The data also show the surface temperature
of the sea ice is increasing every ten years by 1.2 o Kelvin
W. Krabil et al., "Greenland ice sheet: High-elevation balance
and peripheral thinning"Science, Vol. 289, pg 428 (2000) and
R. Thomas et al., "Mass Balance of the Greenland Ice Sheet at High
Elevations"Science, same volume
Data from a comprehensive survey of the ice cap suggest that although
the high elevation portions of the ice sheet are unchanged, the outlet
glaciers are changing. Radar and lidar measurements indicate many glaciers
reaching tidewater are moving faster and thinning. Information on the
NASA Greenland mapping project can be found at: http://aol.wff.nasa.gov/aoltm.htm
"Trouble in Polar Paradise" section of News and Reviews,
Science 297 pg 1489-1514, (30 August 2002). Includes:
Richard Moritz et al "Dynamics of Recent Climate
Change in the Arctic" pg 1497-1501
Eric Rignot and Robert Thomas "Mass Balance of Polar
Ice Sheets" pg 1501-1506
Josefino Comiso in Journal of Climatology v 16, pg 3498
(2003) compared satellite thermal infrared temperature data from
1981 to 2001 and found that Temperature increases across the Arctic
were steeper during the 1990s than the decade before, and were 8 times
more rapid than the 100 year average. Melt season increased by
10 to 17 days per decade
The most dramatic melting
of the Arctic was reported in 2002 by Mark Serreze and Konrad
Steffen of University of Colorado. Greenland showed the greatest
area of surface melt ever measured, and the Arctic Ocean reached record
minimum extent. In Sept 2002 the sea ice extent was 400.000 sq
miles less than the long term average. See Serreze
et al "A record minimum Arctic Sea ice extent and area in 2002"
Geography Research Letters 30(3) pg 1110; and Steffen "Greenland
Maximum Melt Extent" at http://cires.colorado.edu/steffen/melt/index.html.
The Jokobshavn Icestream
research was reported by Bea Csatho, research scientist
at Ohio State University's Byrd Polar Research Center and Waleed
Abdalati, a program manager at NASA. Abdalati presented
the results at the December 2003 meeting of the American Geophysical
Union.
For more information on ice roads and oil exploration related to climate
change, see "Broken Promises: The reality of big oil in America's
Arctic" by Pamela Miller, Arctic Connections (The
Wilderness Society, Washington DC, 2003) Available at http://www.wilderness.org/newsroom/release/20030408
Bruce Peterson, Robert Holmes and James McClelland of the Ecosystem
Center at the Marine Biological lab in Woods Hole report increasing flow
of water from major Eurasian rivers into the Arctic Ocean.
In their study they collaborated with Russian scientists to show these
six rivers, including the Lena and the Ob, discharged 7 percent more
water in 1999 than in 1936. This increase is enough to raise concern
that the amount of fresher water in the Arctic will reach the point
that it affects the generation of Atlantic Ocean currents. "Increasing
River Discharge to the Arctic Ocean" Science 298 page 2171-2173
(13 December 2002).
Gagosian, Robert B. "Triggering Abrupt Climate Change"
Perspective article by the President and Director of Woods Hole Oceanographic
Institution, at http://www.whot.edu/home/about/whatsnew/abruptclimate.html.
"Insight: Climate and Water" a series of articles
on the hydrologic and atmospheric cycles in Nature 419 pg 187-232
(12 Sept 2002)
John Magnuson et al Science 289 pg 1743 (8 Sept 2000)
Northern hemisphere lakes freezing later, thawing earlier over 150
years. From Wisconsin to Siberia, average freeze date change is 5.8
days per 100 years; thaw date averages 6.5 days earlier.
Also, Sagarin and Michili in Nature 294 pg 811 (26 oct 2001)
indicate the 84 year record of the spring break up of the Nenana River
near Fairbanks Ak shows a 5.5 day advancement of the date when the ice
disintegrates. This time is known to the minute because
locals place bets on it.
David Easterling, et al "Climate Extremes: Observations,
Modeling, and Impacts" Science 289, pg 2068, (22 Sept 2000)
This review article lists recorded changes in high temperatures, fewer
frost days, more heavy precipitation, more intense storms, droughts,
etc. Mentions study by E Cooter and S LeDuc in Internat. Journal of
Climatology (1995, Vol 15 pg 650) that the start of the frost free season
in the northeastern US occurred 11 days earlier in the 1990s than in
the 1950s
Eric Rignot, Jet Propulsion Laboratory, Personal Communication
"Global sea level rise is between 1.5 and 2.5 mm/yr over the last
century. There is obviously still considerable debate about the exact
value.... I however do not believe the conclusions that all of the signal
is due to the thermal expansion of the oceans. Glaciers are melting
throughout the world, the trend seems to be increasing, and that includes
Greenland and even parts of Antarctica."
Dan Fagre, USGS Glaciologist, Glacier National Park, Montana,
http://www.mesc.usgs.gov/glacier/glacier_retreat.htm
and personal communication Sept 2000.
Of the 34 named glaciers in the park, and total of 83 perennial ice
and snow areas, all have been receding for most of the century. Only
five glaciers remain larger than 1 sq Km and two others are slightly
smaller. Total permanent snow and ice in the park is now 36 sq Km, with
less than 26 sq Km being true glaciers. Reduction since mid 19th C is
between 77 and 46 percent on fully-mapped glaciers. Grinnell Glacier
(photo) has shrunk 63 percent and receded about 1 km since about 1850.
I received information about Cascade Range glacier recession from
Dr. Robert M. Krimmel , USGS - ICP, Tacoma, WA
Alcides Ames, Peruvian glaciologist, personal communication, July
1999, including directions up to Ururashraju and Broggi glaciers near
Huaraz, Cordillera Blanca
Also see http://unisci.com/stories/20011/0117013.htm
"Small glaciers of the Andes may vanish in 10-15 years" 17
January 2001, about studies conducted on the Chacaltaya glacier in Bolivia
and the Antizana glacier in Ecuador. B. Francou, et al in Ambio, vol.29,
No 7, Nov. 2000.
Cabanes et al Science 294 pg 840 (26 Oct 2001
This study reports a 150mm (6 inch) average sea level rise over 100
years and also confirms the IPCC estimate that about 2/3 of this is
due to climate change & glacial melting. But for 1993-98 the rise
is more than double this rate, over 3 mm /yr, all most all of which
is accounted for by the thermal expansion of sea water. This would mean
a SL rise of 1 foot over the next 100 years.
Mark Meier, presentation at the 2002 American Assn for the Advancement
of Science meeting, Boston Mass, February 16, 2002
Glacier and ice cap retreat now is "unprecedented," and will
result in a greater sea level rise than estimated last year by the IPCC.
"The rate of ice loss since 1988 has more than doubled," he
told the meeting. His calculations are that glacier contribution to
sea level will be at least .65 foot, double the IPCC estimate. (IPCC
estimate of thermal expansion of sea water is .36 to 1.4 feet by 2100.)
In "How Alaska Affects the World", Science 297 pg 350 (19
Jul 2002) Meier and Mark Dyurgerov review these estimates and
say that Alaskan glaciers contribute half the rise.
Anthony Arendt etal "Rapid Wastage of Alaska Glaciers and
Their Contribution to Rising Sea Level" Science (same issue
pg 382).
The authors state that the amount of glacial ablation, about 96 km3/year,
is double that reported from Greenland and that glacier thinning
was twice as fast as measured before. They used airborne laser
altimetry to estimate volume changes of 67 glaciers. A few large glaciers
(Columbia, Malaspina, Bering, LeConte etc) accounted for 75% of the
change.
For more information about glacier melt and contribution to sea level,
see State of the Cryosphere http://nsidc.org/sotc/
I am indebted to Dr. Mauri Pelto of Nichols College for field
information about shrinking NW glaciers. His long-term studies of
Cascade Range ice may be viewed at http://www.nichols.edu/departments/Glacier/nccent.htm
The Climate Impacts Groups of the University of Washington's Center for
Science in the Earth System may be accessed at http://www.jisao.washington.edu/PNWimpacts/
Principal researchers are Edward Miles, Philip Mote, Nathan Mantua,
and others.
Dr. Hector Galbraith, "Potential effects of sea level
rise on intertidal habitat for migrating shorebirds" presentation
to the Ecological Forecasting session, Estuarine Research Federation Conference,
March 2002.
"Over the next few decades global warming is predicted to result
in an acceleration in the current rate of sea-level rise, potentially
inundating many low-lying estuarine areas and intertidal habitats. This
could have important implications for shorebirds that depend on these
areas for feeding habitat during their migrations. ... Even assuming
a conservative global warming scenario (2°C within the next century),
we predict major habitat loss at four of the sites (Willapa Bay, Humboldt
Bay, San Francisco Bay, and Delaware Bay)" from the abstract.
(Study was by Galbraith; S.H. Julius; D. Park; R. Jones; J. Clough;
B. Harrington; G. Page, GES; EPA; Ecomodelling; Stratus Consulting;
Ecomodelling; Manomet Center for Conservation Sciences; Point Reyes
Bird Observatory)
Rising sea level effects on Chesapeake and Delaware Bay marshes were
addressed by Michael Kearney et al in Eos (American Geophysical Union)
April 16, 2002. More than 70 percent of of marshland in both estuaries
is affected. (ENS report April 11, 2002)
The Jokobshavn Icestream research was reported by Bea Csatho,
research scientist at Ohio State University's Byrd Polar Research Center
and Waleed Abdalati, a program manager at NASA. Abdalati
presented the results at the December 2003 meeting of the American
Geophysical Union.
An overview of Greenland ice science may be found in Nature 42, 11 March
2004 pg 114, "A rising tide," by Quirin Schiermeier. It
is reported that all studies show Greenland's ice sheet losing mass and
rapidly flowing out and ablating along the coasts. The bulk of Greenland's
ice, about 3,000 m thick in the center, is a remnant of the great ice
age of 20,000 years ago, say scientists, and contains enough water to
raise sea levels by seven meters.
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