What is the difference between cyclones, hurricanes and typhoons?

Phailin is expected to bring a 3.4-m (11-foot) surge in sea levels when it hits the coast. Credit: APTN

Cyclones, such as the one causing widespread damage in India, are huge revolving storms often caused by winds blowing around an area of low atmospheric pressure.

Characterised as much by their physical appearances as the trail of devastation they often leave behind, these powerful rotating storms are known as hurricanes in the Atlantic, typhoons in the Pacific and cyclones in Asia. All come under the general heading of "tropical cyclones".

A recent trend of increasing sea surface temperatures in the tropical Atlantic had already been linked to strengthening hurricanes in warmer climes.

Scientists in Florida recently looked at maximum wind speeds in an archive of satellite data, and found a significant upward trend was seen for the strongest cyclones, which was linked to rises in sea surface temperature.

Generally a 1C rise in temperature raised the frequency of strong cyclones from an average of 13 to 17 a year, an increase of 31%.

An aerial view in some of the worst hit villages in the cyclone-affected district of Kendrapara on November 1999. Credit: Reuters

India has a history of cyclones, though none this century have been as powerful as Phailin.

Phailin may have only recently made landfall over eastern India, but it has already brought very high precipitation totals to certain areas.

In just six hours, the city of Bhubaneswar recorded 164mm of rainfall (6.5in).