What exactly are superstorms and why was Sandy so destructive? Laurence Pope, MSc Science Communication, explains.

The term ‘superstorm’ isn’t strictly a scientific one, but a subjective name for a very destructive storm event. Hurricane Sandy was technically a tropical cyclone (a hurricane is the name given to tropical cyclones that form in the Atlantic or east Pacific).

Tropical cyclones can be thought of as engines that require fuel in the form of warm, moist air from waters above 27°C. This air begins to rise, eventually condensing in the cooler upper atmosphere, producing storm clouds and releasing excess heat. This heat warms the surrounding cool air, causing that to rise up. Warm, moist air from the ocean surface then rushes in to fill the resulting low pressure void, causing further heating and more rising air, propagating a cycle. Coupled with low winds and the Earth’s rotation the system begins to spin and gain momentum. When it reaches land or cold water it starts to ‘power down’ – but not before causing major damage.

Did global warming produce Hurricane Sandy? No – tropical storms occur regardless of global warming. However, rising global temperatures and warmer oceans could make them more severe.

In the following excerpt from the Imperial College Podcast, Jo Haigh, Professor of Amospheric Physics, talks about the weather and climate situations that led to superstorm Sandy.