Aerosol loading in the Himalayas due to Indian, European and African fossil fuel consumption are likely the largest contributors to glacial retreat in the Himalayas. There are uncertainties if aerosols from China make their way into the Himalayas. Aerosols reduce albedo and increase the skin temperature. This same effect, surface darkening effect SDE , is also leading to a reduction in boreal forest snowpack accumulation video.
It is also having an effect on the Sierra Nevadas in California. The Himalayas is the largest reserve of ice outside of the polar regions. Anthropogenic aerosol forcing is largest contributor to this glacial retreat — not anthropogenic GHG forcing.
There are many uncertainties regarding the role of aerosols in global warming ; it is also the largest source of uncertainty regarding anthropogenic radiative forcing IPCC chart. Scientists have found warm water beneath Antarctica's "doomsday glacier," a nickname used because it is one of Antarctica's fastest melting glaciers.
While researchers have observed the recession of the Thwaites Glacier for a decade, this marks the first time they detected the presence of warm water — found at a "vital point" beneath the glacier. A news release on the findings called it an alarming discovery. The recent article Antarctica melting: Climate change and the journey to the 'doomsday glacier' by Justin Rowlatt, BBC News, January 28, , complements and supplements the items linked to by John Hartz Political, off-topic or ad hominem comments will be deleted.
Comments Policy You need to be logged in to post a comment. Login via the left margin or if you're new, register here. Link to this page. The Consensus Project Website. Settings Use the controls in the far right panel to increase or decrease the number of terms automatically displayed or to completely turn that feature off. Term Lookup Term:. Cambridge University Press. Are glaciers growing or retreating?
Time lapse photography of shrinking glaciers:. Comments 1 to Quietman at PM on 15 July, Sam Spade at PM on 4 June, Sam Spade at AM on 7 June, As a result, we now know just how many glaciers sit in deep water, how deep the water is, and how fjords around Greenland connect to warm offshore waters. In fact, all evidence points strongly in the opposite direction.
The last time the NAO switched to a warm phase was in the mid- to earlys. So we expect it to switch again, sometime between now and the next 15 years. At the end of the day, Greenland is still losing ice, other Greenland glaciers are still retreating and the oceans are warming.
In early August, the OMG team arrived in Greenland to begin its fourth year of ocean surveys to see how the water is changing. The team again dropped sensors in front of Jakobshavn to see if the water is still cold and whether we can expect another year of growth, or for it to resume retreating.
Also, the ice in the middle of a glacier actually flows faster than the ice along the sides of a glacier as shown by the rocks in this illustration right. Glacier Bed : Glaciers move by sliding over bedrock or underlying gravel and rock debris.
With the increased pressure in the glacier because of the weight, the individual ice grains slide past one another and the ice moves slowly downhill. The sliding of the glacier over its bed is called the basal slip. Water lubrication is crucial to either process. These images allow glaciologists to study in very fine detail the way in which glacier ice flows downhill. The cycle, or repeating, color patterns represent an overlaying of information about surface elevation like topographic maps with information about how fast the surface of the glacier is moving.
The glaciers in the images are part of the Bagley Icefield in Southcentral Alaska. On the mountains which are stationary , the color bands represent increasing elevation. On the glacier surface the color bands primarily represent surface speed.
In these images the color bands are like a series of parallel moving sidewalks, each moving slightly faster than its neighbor as one traverses from the edge of the glacier towards the center, so that the ice in the middle is moving the fastest. Moraine : Moraines are mounds, ridges, or other distinct accumulations of unsorted, unlayered mixtures of clay, silt, sand, gravel, and boulders.
There are many types of moraines:. Terminus : The terminus is the lowest end of a glacier. Also called the snout, toe, or leading edge. Meltwater flows through hidden channels and tunnels, reaching the base of the ice to lubricate its flow, and pours from under its face in a silt-laden cloud.
Nunatak is an Inuit term for an island of bedrock or mountain projecting above the surface of an ice sheet, highland icefield, or mountain glacier. The glacier flow has gone around the bedrock, leaving behind this distinct geologic feature.
Scientists use stakes to measure glacier movement. In the picture to the right below, the glacial stream velocity is being measured by a scientist. Glaciers advance and retreat in response to changes in climate. As long as a glacier accumulates more snow and ice than it melts or calves, it will advance. When climbing a glacier, if you could only bring one other thing with you besides warm clothes, boots, and a camera, what would you bring? Exercise: Connect the Words with Definitions Draw lines to connect the words to their definitions.
Roll some Silly Putty into a cigar shape to make it look like a glacier. Then grab the ends and pull it slowly apart. See it sag and still stay as one piece. This is like ice. When ice moves slowly, it flows and deforms. Distributed Active Archive Center. Facebook Twitter. Glaciers Are Solid Rivers. A glacier is a large accumulation of many years of snow, transformed into ice.
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