Europe cools down

2000/01/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Ozeanografia

Paris is further north than Montreal, but its climate is much milder. Those of us who live in Western Europe owe much to the current of the Gulf, since thanks to the hot water that this brings from the Gulf of Mexico, our climate is more temperate than that of North America. The Gulf Stream runs a round trip from the Gulf of Mexico to Norway, providing hot water and cold water. The current contains two main pumps, one in the Labrador Sea and one in the Greenland Sea, which allow to maintain the movement of the current.

A few years ago scientists suggested that the Gulf stream could stop moving due to global warming, but then they had no proof. Now, however, some researchers believe they have discovered these tests.

The scientist Bill Turrel has studied more than 17,000 measurements of salinity carried out between the Shetland and Faroe islands since 1893 and has concluded that in the last two decades the salinity level of the waters of those seas and, therefore, its density has decreased by 10 g of salt mines per m3. The change is the largest of the last 100 years (the salinity level used in the 1950s to calibrate marine appliances was so stable) and fits other measurements made: Between 1988 and 1997 the water level at -0.5 °C has risen 60 m; between 1982 and 83 the deep waters moved to 10 cm per second to the south (pushing the Gulf stream) from the Greenland Sea to the Norwegian Sea, but in the years 1983-93 the deep waters were contrary to 1 cm per second.

While all these data are evidence that changes are occurring in ocean currents, it cannot be concluded that global warming is responsible for change, even the origin may be natural.