Glaciers around the world and Arctic/Antarctic ice are melting as a result of climate change. Ice is showing its susceptibility to even small rises in temperature. The continuing disappearance of glaciers and destruction of ice shelves is causing great concern.
The collapse of the Larsen B ice shelf in the Antarctic in 2002 is continuing. After having been one of the largest and fastest deteriorations scientists have ever seen, recent measurements show the ice shelves held glaciers in place. Absent the shelves the glaciers have increased the speed of their flow causing a profound thinning that weakens them even further. The glacier flow speed increased by 55% from 1997 to 2012 as the glaciers shrank even further.
A research team from the Scripps Institution of Oceanography in San Diego analyzed 18 years of satellite observations. They determined the loss of ice-shelf volume in Antarctica increased from about 25 cubic kilometers per year from 1994 to 2003 to in excess of 300 cubic kilometers each year from 2003 to 2012.
Scientists have discovered ocean mixing that causes floating Arctic ice to be vulnerable to melting from warmer water below in an updraft that carries heat upward. The article in the February 19, 2015 issue of Nature magazine states, “As sea ice disappears, the atmosphere can transfer more of its energy into the ocean which drives ocean mixing.”
Researchers led by Gary Clarke of the University of British Columbia in Vancouver, Canada, have used climate models to predict 70% shrinkage of glaciers in Western Canada by the end of 2100 relative to those seen in 2005. Their report states, “We project the maximum rate of ice volume loss, corresponding to peak input of deglacial meltwater to streams and rivers, to occur around 2020-2040.”
Climate change deniers used the surging or apparent growth of glaciers in the Himalayas as evidence that there is no global warming. But scientists now suggest the glaciers of the Karakoram Range, which cover a total of 18,000 square kilometers or represent more than half the ice content of the Himalayas, are actually “surge” glaciers. This means they are not necessarily adding to their mass but merely redistributing.
An article by Jane Qui in the March 27, 2015 issue of Science magazine, entitled “Himalayan ice can fool climate studies” states, “The 20 or so Karakoram glaciers they analyzed surged on a ‘surprisingly consistent’ schedule, he says (Frank Paul of the University of Zurich), at intervals ranging between 25 and 75 years….After a surge, the lower part of the glacier thins while snow accumulates on the upper part until it reaches a critical threshold, triggering another surge.”
Many scientists now believe the limit placed by most countries of the world on the heat rise from climate change will outstrip the +2° limit. While developing nations are pushing for a lower limit of +1.5°, most scientists believe this is to increase the size of assistance their countries receive from wealthier nations. These poorer nations charge it was the wealthy countries’ economic progress that created the problem.
An article appearing in the April 2, 2015 issue of Nature magazine states, “It has become increasingly clear, however, that temperatures are destined to soar well beyond anything that humans have ever witnessed. Even if countries keep to the emissions pledges they have made up to now, climate models predict that the world is on track for about +3° C of warming this century.” This is the lowest level of the forecasted range of possibilities.
On a final note, we know the ice around the world is disappearing because we have seen our first article about how climate change has a negative impact on being employed. The article in the April 16, 2015 issue of Nature magazine states that scientists who cover the cryosphere (places on Earth that are sheathed in ice) are having a difficult time coping with changes as a result of melting ice shelves and glaciers.
There are two effects of climate change that are being exacerbated by this disappearance of ice. Glaciers provide water to downstream populations and their shrinkage will limit the fresh water that is available. Ice shelves that are breaking up and melting will increase the water in the oceans and lead to a rising of ocean waters.
These effects are real and need to be of concern to everyone. We need to push our elected representatives at all levels to acknowledge that these effects are real and must be dealt with before they reach the crisis stage. We must have drinkable water and cannot afford to let the ocean invade the land.
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