While not expected to happen in the next year or two, scientists believe the UK will begin to experience drier summers within a decade.
Scientists at the University of Reading say that major currents in the North Atlantic Ocean seem to be slowing down, which could have an impact on Europe's warm and temperate climate.
These currents, named the Atlantic Meridional Overturning Circulation (AMOC), bring warm tropical waters up to the latitudes of Britain, but if they begin to cool it could result in drier summers.
Dr Jon Robson, from the National Centre for Atmospheric Science (NCAS) at the University of Reading, who led the research, said: "Our findings suggest there could be a relative cooling of the North Atlantic sooner rather than later, perhaps over the next decade or so.
"In Britain we could see a return to drier summers, although it could also lead to more droughts in parts of Europe and Africa. However, there's quite a bit of uncertainty about how fast changes might happen, and other influences - such as sea ice and greenhouse gases - are also important.
"There's lots of evidence that the AMOC is important for European climate, and seeing how these events unfold is a great opportunity to understand this influence better. There's no evidence this slowdown has been caused by global warming, although we can't rule out some link."
Direct measurements of the AMOC have shown a 10-15% slowdown since 2004 and the work by the University of Reading also measured changes in the deep North Atlantic (below 1kn).
The scientists' findings suggest a larger slowdown, starting in the 1990s, and showing no sign of stopping yet.
This weakening of the AMOC is likely to cause a cooling of the North Atlantic Ocean, which has until recently been in a ‘warm' phase.
The knock-on consequences could include a reversal of the recent pattern of wet summers in Britain, fewer Atlantic hurricanes, and potentially damaging droughts in the Sahel region of North Africa.
Comments