In general,
glaciers retreat due to a combination of rising temperatures and declining precipitation, but the temperature and precipitation records from the Alps indicated that glaciers should have continued advancing until around 1910.
As
these glaciers retreat due to global warming (see Chapter 1), river flows are increased in the short term, but the contribution of glacier melt will gradually decrease over the next few decades.
Basically they find that even though temperatures were very low during the last iceage,
the glaciers retreated due to the very dry atmosphere.
Not exact matches
Geology textbooks will tell you that we are now 12,000 years into the Holocene Epoch, a time marked by violent geologic upheavals
due to
retreating glaciers and surging sea levels.
The new result focuses on ice loss
due to a major
retreat of an outlet
glacier connected to a long «river» of ice — known as an ice stream — that drains ice from the interior of the ice sheet.
He says: «However, as far as the mid-19th century is concerned, forcings
due to GHG concentrations are insignificant so we are only left with natural forcings (or causes) as an explanation for
glacier retreat.»
Since IPCC (2001) the cryosphere has undergone significant changes, such as the substantial
retreat of arctic sea ice, especially in summer; the continued shrinking of mountain
glaciers; the decrease in the extent of snow cover and seasonally frozen ground, particularly in spring; the earlier breakup of river and lake ice; and widespread thinning of antarctic ice shelves along the Amundsen Sea coast, indicating increased basal melting
due to increased ocean heat fluxes in the cavities below the ice shelves.
However, as far as the mid-19th century is concerned, forcings
due to GHG concentrations are insignificant so we are only left with natural forcings (or causes) as an explanation for
glacier retreat.
He says: «However, as far as the mid-19th century is concerned, forcings
due to GHG concentrations are insignificant so we are only left with natural forcings (or causes) as an explanation for
glacier retreat.»
If mid-19th century
glacier retreat is not
due to human causes then why can't 20th century
glacier retreat simply be an extension of that same natural process.
The Heartland Institute's propagation of the notion that the Kilimanjaro
glacier retreat has been proved to be
due to deforestation is even more egregious.
Retreating tidewater
glaciers dominate the Alaskan sea level contribution
due to their ability to efficiently transfer mass via iceberg calving [Arendt et al., 2002].
Now, two new studies conducted by researchers at NASA and the University of California, Irvine, have revealed that
glaciers in West Antarctica are
retreating at an unprecedented rate
due to warm water circulating beneath the ice shelf.
Of course, other reasons could exist for
glacier retreat (e.g. Kilimanjaro's
glacier retreat is apparently
due not to increased temperatures but rather to decreased participation — and perhaps human clearing of trees has a role in that!)
Two new studies conducted by researchers at NASA and the University of California, Irvine, have revealed that
glaciers in West Antarctica are
retreating at an unprecedented rate
due to warm water circulating beneath the ice shelf.
27 January 2000: The Hektoria
Glacier system is stable, but increased summer melting from climate warming in the 1980s and 1990s affected the
glacier system in two ways: (1) a seasonal speedup from summer melt water percolating through the
glacier ice to its base, and (2) initial
retreat of the Larsen Ice Shelf
due to the effects of melt ponds (downstream from this image).
During the 1984 - 1994 period
glacier retreat rates have increased substantially
due to negative annual balances (Pelto, 1993).
This can be affected by warming temperatures, but also by changes in snowfall, increases in solar radiation absorption
due to a decrease in cloud cover, and increases in the water vapor content of air near the earth's surface.2, 14,15,16,17 In Cordillera Blanca, Peru, for example, one study of
glacier retreat between 1930 and 1950 linked the
retreat to a decline in cloud cover and precipitation.18
Changes occurring
due to
glacier retreat have been observed in the Lewis
Glacier Basin.
The
retreat of Greenland's
glaciers has been largely
due to intruding warm waters driven by changes in natural ocean oscillations.
Some possible effects of global warming are the inundation of low - lying islands
due to rising sea levels, increased frequency of severe storms and the
retreat of
glaciers and icecaps.
Between 1913 and 1945 the rate of
retreat for the Sperry
glacier was 10 times faster [
due to drought] than rate of
retreat since 1979.
For the first time, wide - ranging impacts of changes in current climate have been documented:
retreating glaciers, longer growing seasons, shift of species ranges, and health impacts
due to a heatwave of unprecedented magnitude.
5.3.4 In Europe, wide ranging impacts of changes in current climate have been documented:
retreating glaciers, longer growing seasons, shifts in the geographic spread of species, and health impacts
due to an unprecedented heat wave.
In the face of Zwally's analysis, defenders of the CO2 warming meme
retreated to stressing uncontested observations of lost ice
due to dynamic
glacier thinning or uncritically accepting speculative models of catastrophic deglaciation.
There are many other references dating from this period available from the Alps: records of advancing snow and ice burying silver and gold mines, alpine villages, farms and pastures being abandoned
due to colder climate, even physical evidence recovered today under
retreating glaciers.
The pro-glacial lake is
due to massive
retreat of the
glacier in recent decades.
Retreating glaciers = global warming, advancing
glaciers = more snow
due to global warming.
* The earth is getting warmer * Sea levels are rising *
Glaciers are
retreating * AC02 concentrations have risen since pre-industrial ages & this rise is mainly
due to the burning of fossil fuels * AC02 is a GHG * Anything else that does not pertain directly to the evidence for causality.
I await the explanation of why the other
glaciers of the world, unaware that they don't need to melt because
glacier retreat in the Himalayas is
due to local factors, nevertheless also melt.