Shipwrecks, tree rings reveal hurricanes.

• Position: The Caribbean

Records of Spanish shipwrecks combined with tree-ring records show the period 1645-1715 had the fewest Caribbean hurricanes since 1500, according to research led by the University of Arizona, Tucson. A 75% reduction in the number of Caribbean hurricanes was found; this during a time with little sunspot activity and cool temperatures in the Northern Hemisphere. "By combining shipwreck data and tree-ring data, we are extending the Caribbean hurricane record back in time and that improves our understanding of hurricane variability, says lead author Valerie Trouet, associate professor in the Laboratory of Tree-Ring Research.

Although global climate models indicate hurricanes will be more intense as the climate warms, those models are not yet good at making regional predictions, Trouet points out. Learning more about how hurricanes correlated with climate for the past 500 years may lead to better regional predictions. "We're providing information that can help those models become more precise."

What is now the U.S. National Hurricane Center did not begin keeping records of Caribbean hurricanes until 1850. Researchers have used lake sediments to develop a record of hurricanes...