Our planet’s oceans are in constant motion as dense (salty or cold) water sinks, driving a worldwide system of currents. The warm waters of the Gulf Stream increase temperatures in northern Europe by several degrees, but such currents are themselves vulnerable to changes in our climate.
Global warming is causing Arctic sea ice to melt, dumping excess freshwater into the north Atlantic. This could in turn affect the currents of dense water sinking in this region and slow down the Gulf Stream in coming years. Recent measurements seem to support this theory, but the complexity of global climate systems makes it very difficult to prove beyond doubt.
Answered by Alexandra Cheung