It's a déjà vu. It seems as if you read every few years, Gulf Stream will become weaker. (and probably everyone always thinks about same movie – more on that later.) Last Thursday, science journal Nature published two articles on mysteries of North Atlantic. So, is it so far again? A time-lapse journey through history of Gulf Stream research shows context in which new findings stand and what is different.
1. The object: attention and imagination of people apply to a gigantic liquid conveyor belt in ocean. "Atlantic Meridional overturning circulation" is name, abbreviated AMOC. This north-South circuit directs warm water to north, where it cools and becomes denser, so that it sinks and flows southwards through deep seas again. For laymen, this is all "Gulf Stream". Strictly speaking, however, Gulf Stream is only one stage of this conveyor belt off US east coast. Later he forks, in south he aspires towards Canaries and West Africa, in north he continues as North Atlantic stream.
Already in year 1855, U.S. Naval officer and marine scientist Matw F. Maury compared oceanic conveyor belt with a "heating apparatus for Britain, North Atlantic and Western Europe". The metaphor of Europe's central heating was in world.
2. The false alarm: researchers are aware of several episodes of History of sea in which conveyor belt has failed in Atlantic. At same time, cold periods in Europe and North America broke in. The question arises as to wher this has a meaning for today.
In November 2005, Oceanographers wrote in nature, circulation had "slowed down by about 30 percent between 1957 and 2004". They were based on measurements in front of Canary Islands. Only or test drives could not confirm alleged trend. And for a time, it was said that outside specialist circles, "The Gulf Stream" was stable overall, but re was also little reliable long-term data.
This article comes from time No. 17/2018. Here you can read entire output.3. The excerpt: in June 2015 n in science a comparison of different measurements from past ten years showed two things: first, an enormous variability of flow from year to year and secondly a decrease over GES Lonely period.
The complex image in which oceanographers had to classify se new (and furr) data such as puzzle pieces also includes melting of Greenland's ice masses. What y might have is better understood: because ice sheet melts, freshwater pours into North Atlantic. It lowers salt content of water surface and thus density, so that cold surface water decreases more slowly into depth. This could slow down entire conveyor belt system. "It is very likely that AMOC will become weaker in course of 21st century," world IPCC summed up level of knowledge in year 2014.
Date Of Update: 21 April 2018, 12:02
