Hurricane forecast

Scientists at Florida State University's Center for Ocean-Atmospheric Prediction Studies (COAPS) have developed a new computer model that they hope will predict with unprecedented accuracy how many hurricanes will occur in a given season.

After about five years developing and assessing the model, associate scholar scientist Tim LaRow and his COAPS colleagues are putting the system to the test this year with their first-ever hurricane forecast. The COAPS model is one of only a handful of 'dynamic models' in the world being used to study seasonal hurricane activity.

The COAPS model has predicted a below-average season in the Atlantic Ocean, with a mean of eight named storms and four hurricanes based partially on emerging El Nino conditions.

During an El Nino, the warmer ocean temperatures in the tropical eastern Pacific tend to suppress hurricane activity in the Atlantic. The historical seasonal average is 11 tropical storms and six hurricanes.

LaRow and COAPS researchers Lydia Stefanova and Dong-Wook Shin issued their forecast on 1 June, the official start of the six-month hurricane season. The tropics traditionally do not become active until the early autumn, so it is too early to tell if the forecast is on track. However, the researchers have good reason to feel confident.

Before making this year's prediction, they used the model to perform 20 years of re-forecasts, or hind casts, using the sea surface temperatures determined by the National Oceanic and Atmospheric Administration (NOAA) on 1 June of every year from 1986 to 2005. They found a very high correlation between the model's predictions of the number and intensity of tropical cyclones and what actually occurred during those years.

In 2006, COAPS received a $6.2m (£3.8m), five-year grant from the NOAA that has been used, in part, to support the development of the model.