Hurricanes start off as tropical depressions (centres of low atmospheric pressure) over tropical oceans. Three things must happen for a hurricane to form. A continuous evaporation and condensation cycle must take place; there must also be patterns of winds that are characterized by the converging winds, and a difference in air pressure between the surface and high altitude. In the warm waters of the eastern Atlantic, water vapour rises from the ocean and then cools forming clouds and releasing heat energy which fuels the storm. This sucks in more warm air generating strong winds which shoots upwards. When this rush of air hits the stratosphere it flattens out and after getting influenced by earth’s rotation the storm starts turning counter clock wise. When the winds reach 39 mph it is considered a tropical storm. If there are aren’t any wind shears the storm’s air in the upper atmosphere will raise to higher and higher pressures resulting in hurricanes. So, Hurricanes are basically like giant engines that use warm, moist air as fuel. The deadly winds caused by hurricanes result in a massive bulge of water called a storm surge by pushing down on the ocean surface. 90% of the casualties in hurricanes are due to the storm surge.
Hurricanes have always bedevilled coasts, but global warming may be making matters worse. The most important parameter which determines hurricane intensity is sea surface temperature. Warmer water means more availability of warm, moist air thus incensing hurricane intensity. As heat from the ocean fuels the storm, an increasingly larger proportion of tropical storms are turning into hurricanes. Sea level is rising and will continue to rise as oceans warm and glaciers melt. Rising sea level means higher storm surges, even from relatively minor storms, which increases coastal flooding and subsequent storm damage along coasts.
Hurricane Katrina was the most devastating hurricane in recent history which ravaged through New