Thursday, January 6, 2011

Important Heat Flow Change in Gulf Stream





This is big news.  I posted four years ago now that the most likely explanation for the apparent changes in the climate and in particular, the specific erosion of sea ice in the Arctic was a specific change in the total heat been delivered by the Gulf Stream which we may simply label delta H.  Simply applying a delta H since the seventies perfectly explains our observations since then and led me to predict a possible pending complete breakup of the Arctic sea ice as early as 2012 and inevitably soon thereafter.

We continue to have warmer than normal Arctic conditions.  However the Navy is claiming that the ice has finally began to thicken again over the past two years.  So far it is the only available evidence that the warming delta H may have ended.  If it has ended, then an Arctic breakup is aborted.

This report tells us that for the past forty years that the Labrador Current was much weaker.  This means several things.

1                    A strong current mixed vigorously with the Gulf Stream, partially cooling it.  This was hugely reduced when the current abated.
2                    A warmer Gulf Stream carried more heat or delta H as a consequence into the Arctic and was instrumental in eroding the sea ice.
3                    An offsetting counter flow somewhere else took over and this had little effect on the Gulf Stream.  The net effect was to modestly strengthen the Gulf Stream.

Now the geological record shows us that the Gulf Stream has been much warmer by a couple of degrees and that long cyclic warm eras are common.  If my own interpretation holds up, we are entering a prolonged warm period in Europe similar to the Medieval optimum as part of an apparent thousand year cycle that I have been able to identify on a preliminary basis over 5,000 years.

I would be quite surprised if the implied claim of no similar events for 1800 years were to hold up.  Right now we have a well positioned coral reef able to act as a monitor.  There will be others and we may be able to go further with this form of testing.

ATLANTIC CIRCULATION ON THE FASTTRACK FOR CHANGE
Analysis by Tim Wall 
Tue Jan 4, 2011 05:55 PM ET 




Bell-bottom jeans, Abba, and the Labrador Current -- one of the three is not making a retro comeback. Temperature-tracking coral reefs indicate that the circulation of water in the Atlantic Ocean has changed dramatically since the 1970's.

That could be part of the reason areas in the northern hemisphere have had harsh winter storms and summer droughts say researchers.
The evidence for changing currents comes from ancient gorgonian coral reefs growing off the coast of Nova Scotia. The reef was studied by a team of biochemists and oceanographers from Switzerland, Canada, and the United States.

Like most organisms, corals are what they eat and changes in their diet are recorded in the reef structure.
The Canadian corals showed that the cold, south-bound Labrador current is losing ground to the warm, north-bound Gulf Stream current. The corals of the deep north Atlantic have been feasting on nutrient-rich warm water since the 1970's.

The researchers looked at the concentrations of a certain isotope of nitrogen, called delta 15. Different concentrations of the isotope allow scientists to trace a creature's food sources.

The levels the researchers found in the Nova Scotian coral indicated the coral had been feeding heavily on nutrients brought north from the subtropical regions for approximately 40 years.
The coral had been feeding primarily on subarctic nutrients for the previous 1800 years.
That abrupt change in food sources caused by changes in currents coincides closely with the onset of observable changes in Earth's climate caused by industrialization.
"The researchers suspect there is a direct connection between the changes in oceanic currents in the North Atlantic and global warming caused by human activities," said one of the participating institutions, the Swiss Federal Institute of Aquatic Sciences and Technology in a statement to the Associated Foreign Press.
The coral reef research was published recently in the Proceedings of the National Academy of Sciences.

Recent heavy snowfalls and harsh winter storms along with droughts and heat waves in the summer, could be explained by a changes in the circulation of the Atlantic's water, say climate researchers. A 2004 paper by NASA explained the possibility of melting arctic sea ice triggering colder weather in Europe and North America.

As my colleague, Mr. Cox, pointed out in the above blog post, the term global warming is a misnomer in many senses. Humanity faces global climate destabilization. The weather patterns our agriculture and industry have adapted to over the centuries are changing rapidly.




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