FYI: What's the difference between cyclones, typhoons and hurricanes?

With the preliminary death toll from the cyclone that laid Myanmar's Irrawaddy Delta to waste in the tens of thousands, the destructive power of the weather has once again been on full display. Climate change is apparently boosting the frequency of extreme-weather incidents and there's a smorgasbord of storm-like activity to fret about - typhoons, hurricanes, tropical depressions, gales, monsoons, blizzards and 'black' rainstorms. Meteorological threats appear every bit as hazardous as the more human dangers governments are constantly looking out for.

But anyone who nervously watches the skies can take heart; deadly weather may not be as ubiquitous as you think. This isn't to say severe storms aren't a terrible fact of life in some parts of the world; they're just much more limited in variety than they first appear. 'Cyclone', 'typhoon', 'hurricane' and even 'tropical depression' are all basically names for the same thing.

Cyclones are generally explained as cloud-heavy low-pressure systems that react to passage over warm - tropical or sub-tropical - waters. They create convection-like effects resulting in heavy rain, lightning and intense winds that rotate around a central point. 'Hurricane' covers any such storm that takes place in the North Atlantic Ocean or the northern and southern stretches of the Pacific Ocean east of the international dateline. 'Typhoon' applies to the North Pacific area situated west of the international dateline - including Hong Kong. These titles are only used when cyclones pack sustained surface winds of at least 119km/h; anything less than that and they're known as tropical storms. Tropical storms that have winds of a piddling 63km/h or less don't even earn that title - they're downgraded to tropical depressions. A storm system needs to be of at least tropical-storm strength to to be given a name, a system that is designed to ease communications between weather forecasters, authorities and populations in an emergency situation.

On those rare occasions when winds reach 179km/h or above, the weathermen will start talking about a 'super typhoon' or 'major hurricane'. These storms will be assigned ratings of three, four or five on the most commonly cited hurricane-severity standard, the Saffir-Simpson scale (which, incidentally, the authorities in Hong Kong don't use). To put the fury of these systems in perspective, on a typical day, one would, if it were harnessed, generate enough electricity to power half the planet.

Given subtropical Asia's abundance of balmy waters, it's no surprise more major storms find a home here than anywhere else.

The award for the worst cyclone in history, in terms of fatalities, goes to one that battered Bangladesh in 1970. So chaotic was the aftermath of the storm that authorities are still squabbling about the exact death toll, but 300,000 is a widely accepted estimate. In monetary terms, first prize goes to Hurricane Katrina, which, in 2005, cost communities in the Bahamas, Florida and Louisiana a total of US$81 billion. Typhoon season is no fun but the storms that descend on Hong Kong look like a little light rain in comparison; only nine deaths have been attributed to typhoons since 2000 and the deadliest local storm on record, Typhoon Wanda, killed 130 people way back in 1962.