Study to focus on Arctic after Greenland Sea found to have warmed 10 times faster than global ocean
By Phoebe McDonald
Updated Sat 2 Nov 2013, 4:57pm AEDT
“Scientists have revealed plans to examine temperature changes in the Arctic Ocean after a long-term study found the Greenland Sea is warming 10 times faster than the global ocean.”
Sky: There are some troublesome by the by statements here that deserve special attention. Some 10 years or so ago, there was a report that the flow of the Atlantic Current at its northern edge was decreasing: Let me see if I can find the reference. Here we are:
01 December 2005
“The Atlantic Ocean overturning current that maintains Europe’s moderate climate has slowed by 30 per cent according to scientists from the National Oceanography Centre at the University of Southampton in research published today in Nature (Thursday, 1 December 2005).”
Then there was a retraction that not enough data had been collected. Then there was an article about how many monitors had been strung along a horizontal line across the Atlantic to measure the flow. Then nothing. No reports. Nothing. Now, in this article I read:
“Until the early 1980s, the central Greenland Sea has been mixed from the top to the bottom by winter cooling at the surface making waters dense enough to reach to sea floor,” she said.
“This transfer of cold water from the top to the bottom has not occurred in the last 30 years.
“After the ’80s it seems that winter heat losses – how much heat is lost from the ocean to the atmosphere – has decreased.
“The waters at the surface are lighter during the wintertime than before. They don’t reach the necessary density to reach the bottom of the Greenland Sea.”
In the past, the Thermohaline Circulation Conveyor [Atlantic Current] was driven by the sinking of the cooled down, saltier [heavier] water having been mixed with the cooler water from the higher latitudes. This drove the circulation current as we all know keeping winter temperatures several degrees warmer in Europe, especially the British Isles. It has always seemed common sense to me that as the arctic ice melts, a greater and greater volume of cold water will push this overturning further and further south.
“She says if current trends continue the density, temperature and salinity levels of deep water in the Greenland Sea will reach the same levels of those in the Arctic Ocean.
“The Greenland Sea is getting lighter … It will reach the same density of the waters that are coming in,” she said.
“When they reach the same density we don’t know what will happen.”
Well, I think she has a good idea. This means the end of the conveyor effect at that latitude. Remember, It is only in recent times that the vast accumulation of ice of the Arctic Ocean has melted. Before that time, there was not nearly the volume of colder water mixing with southern currents at that latitude.
I would like to see a report from all the meters strung out to measure current flow across the northern Atlantic. If the Greenland see continues to warm and the warm saltier waters from the south are not cooled sufficiently to make them sink, then the conveyor will end. Period. How fast is unknown.