IF THE GULF STREAM STOPPED FLOWING…
The Gulf Stream could be “turned off” by just the type of development we see at the moment. And if it happens, it will happen quickly: The global temperature will increase, resulting in deglaciation and more rainfall in the north. This can weaken the so-called deepwater production - the motor that fuels the Gulf Stream. It cools the warm salty water of the Atlantic, causing it to sink, and then flow southwards again along the seabed.

In the programme, we are told that both glaciers and sea ice are melting in the Arctic and that the deepwater production system is already changing. A climate model from the Hadley Centre in Britain predicts that one of the two deepwater production systems feeding the Gulf Stream will disappear within the year 2030.

But ocean/climate systems are extremely complex. One way of finding out what can happen, is by studying earlier climate changes. This can be done with the aid of drill cores from pine trees, sediments and ice. The programme shows us what happened during the “Little Ice Age”, when a drop in temperature of just one degree, resulted in years of famine for the whole of northern Europe. An even more dramatic change in climate happened approximately 12.000 years ago, when the climate suddenly changed and returned to ice age conditions. There were several such changes also before and during the last ice age, when for example temperatures in southern Norway dropped suddenly to arctic levels.

It is impossible to predict with any degree of certainty, the sort of conditions that are needed to trigger this type of change. But we do know that it can happen under conditions similar to those found at present – with global warming.

If the Gulf Stream stopped flowing… was shown on NRK1 in 2001 and had very good ratings.

Programme length: 28 min.