Anyone going on holiday to the Caribbean or southern coasts of the US needs to be aware of the risk of hurricanes, especially at this time of year. But tourists to the Mediterranean may need to watch out for hurricanes in the future.

This year brought the fastest intensification of a hurricane, when Humberto exploded from a tropical depression to a hurricane in just 16 hours. In 2005 there was a record number of hurricanes, including the most intense one yet on record.

Tropical cyclones also are cropping up in unexpected places: in 2004, the first hurricane appeared in the South Atlantic and struck the coast of Brazil, and a year later Hurricane Vince formed near the Madeira islands in the Atlantic and became the first known hurricane to hit Spain.

Climate change might be responsible for altering these areas where tropical cyclones develop. A recent study looked at climate change forecasts and revealed for the first time a risk of a tropical cyclone development over the Mediterranean as the waters there warmed up.

Although there were large uncertainties in the forecasts, the heat stored in the sea is expected to boost the intensity of storms, eventually triggering Mediterranean hurricanes.