The huge glaciers of Greenland, to the oldest, most slow and seemingly most reliable features of the climate system, fall apart. You are not only from the warming melt polar atmosphere, but quickly reduce under the attack of the warmer ocean currents.
BLOG: Education a rapidly melting glacier
Fiamma Straneo's physical oceanographer from the Woods Hole Oceanographic Institution traveled with colleagues from small fishing boat and helicopter and icebreaker the inner sanctuary of hide helmet home glacier cold ice cream smothered to reach fjord. One of Greenland's largest glaciers since 2003 quickly withdrew.
"Glaciers are much faster they move thinning are, they break up and they are retreat," Straneo says in the latest issue of the Woods Hole online magazine, Oceanus. "they are dumping more ice into the ocean." "Glaciers are changing how they work."
Much of the change is the result of the warmer currents eating away at the base of the ice age tongue.
Greenland's many outlet tide glacier flow usually in the head of a long, finger-like fjord which left meltwater looks which from a distance like a Bay. Like most has helmet home glacier a "Tongue" or shelf ice, which from extends above the surface of the Sermilik fjord, which tends, as a dam, slows the upstream glacier. Today, this function is less than above the rapid retreat of the ice began some years ago.
Straneo wrote much of the change in the glacier is driven by what under the seemingly placid surface of the fjord before him is, recently in the journal Nature Geoscience. The team was surprised to find the flow of the strong currents at different depths. Checkpoints in the fjord lowered Straneo were a number of measurements of temperature and salinity at different depths, that reveal two different layers: cold, fresh water on the surface, up to about 150 metres, sitting on top of salty, denser subtropical waters of the North Atlantic polar, the warm enough to melt ice is also in the winter.
A surprise", we found was that the warm water in the fjord actually 1 degrees Celsius warmer in the winter, which is much of Greenland standards." Straneo, the possibility raises it, that melt may be greater than in the summer, "said Winter prices in a WHOI press release."
Unexpectedly, melted water seems from the glacier, rather than on the top, between the cold polar surface waters and the warmer North Atlantic pay layer below it.
Not all of the details around Greenland's changing glaciers are known, but the image is the design of more kompliziert-- and less predictable. Yet one thing is clear: the North Atlantic current, which is subtropical water deep is warmer fjords in East Greenland and substantially more actively strengthen glacial collapse which in the process.
Figure 1: from the video animation "Where glaciers meet the sea" Woods Hole Oceanographic Institution.
Figure 2: Fiamma Straneo lowers a temperature salinity recorder in the icy waters of the Sermilik fjord, East Greenland, March of 2010. credit: Kjetil of vague, Woods Hole Oceanographic Institution.
没有评论:
发表评论