katrina

Katrina and Rita in a row over the Gulf of Mexico is an unprecedented and troubling occurrence.

But for most tropical meteorologists the truly astonishing "storm of the decade" took place in March 2004.

Hurricane Catarina — so named because it made landfall in the southern Brazilian state of Santa Catarina — was the first recorded south Atlantic hurricane in history.

Textbook orthodoxy had long excluded the possibility of such an event; sea temperatures, experts claimed, were too low and wind shear too powerful to allow tropical depressions to evolve into cyclones south of the Atlantic Equator.