Global warming can lead to a colder Britain
Britain has just suffered its coldest winter for 100 years, bringing freezing, snowy weather that paralysed the country. Scientists say that these icy winters could become a regular feature simply because the world is getting warmer.
Dr Simon Boxall of the National Oceanography Centre in Southampton says that research has shown that as the planet gets warmer the Arctic ice is shrinking much faster than had previously been predicted. The ice was now of an area that it was not expected to reach until 2070.
As a result of the increase in Arctic ice melt, enormous quantities of fresh water are being dumped into the sea. This is upsetting the circulation of ocean currents. Previously cold water in the high Arctic has sunk into the deep sea and pulled in warmer water from the Gulf Stream. It is this warm tropical water that keeps northwest Europe warmer than it would otherwise be, largely by warming up the prevailing southwesterly wind to keep the temperatures mild on land.
Scientists believe that if levels of fresh water significantly increase and the Arctic seas grow warmer, this could reduce the pull of the current and unbalance the weather patterns around the world.
Dr Boxall was speaking ahead of an expedition to the Arctic ice cap as part of efforts to establish just how fast the ice really is melting. Explorers with the Catlin Arctic Survey expedition will venture out and drill holes through the ice down into the ocean to measure temperatures, levels of salinity and the flow of fresh water just below the sea ice. It is hoped that data gathered will help scientists to predict the level of change in ocean currents.
Dr Boxall was anxious to point out that there was no suggestion at present that the Gulf Stream would stop and that we were certainly not going to see the English Channel freezing over, but he predicted that colder and harsher winters will become the norm and summers will become colder and wetter.
It's not catastrophic, said Dr Boxall, but we are more likely to be skiing in Yorkshire than sitting under palm trees.
If on the other hand if the Arctic heats up too much, which could be anywhere from now until 50 years time, the Gulf Stream could be turned off. This would be fairly sudden and our climate would become like that of north west Canada or Alaska.
Scientists from Cardiff University have also been looking at the effects of changes in the circulation of Atlantic Ocean currents. Their research indicates that radical changes in the circulation of the Atlantic Ocean can take place within a timescale as short as a few decades. They predict that if there is a reduction of the flow of the Gulf Stream as less cold water sinks in the Arctic there will be a drop in temperature of up to 10 degrees Celsius around the coast of northwest Europe.
Of course, they might be wrong.