A study of Spanish shipwrecks and tree-ring records revealed the period from 1645 to 1715 had the fewest hurricanes in the Caribbean, since 1500. The research was the first to utilize shipwrecks as a hurricane activity substitute.
The University of Arizona-led study found that the period, also know as the Maunder Minimum, had the fewest numbers of Caribbean hurricanes - a 75 percent reduction. Lead study author Valerie Trouet explained that by fusing shipwrecks and tree-ring data, they were able to study past hurricane records and advance the information on hurricane variability.
According to global climate models, hurricanes will become more intense with climate change. However, the current models have yet to make reliable regional hurricane predictions. Analyzing hurricane and climate correlations in the last 500 years could aid in predicting regional hurricanes better.
"We found that in the years when many ships wrecked in the Caribbean, the trees in Florida Keys showed the same signal that trees show during hurricanes," said Trouet, an associate professor from the University of Arizona's Laboratory of Tree-Ring Research.
The U.S. National Hurricane Center only started recording Caribbean hurricanes in 1850. The research team studied lake sediments to create hurricane records in the past centuries, going all the way back to 1500.
Sea travel on the Caribbean became a routine for Spain, this is why it had detailed records of ship travels. Storms accounted for many of the shipwrecks in the Caribbean.
Florida Keys' tree-ring records extend all the way back to the 1707. These tree-rings show when there is a hurricane in a particular year, because the ring growth slowed down whenever one occurs. The team gathered wood samples from shipwrecks and began dating them.
The team used two books in the study to combine shipwreck data with tree-rings data, namely "Shipwrecks In The Americas: A Complete Guide To Every Major Shipwreck In The Western Hemisphere" by Robert F. Marx and "Shipwrecks Of Florida: A Comprehensive Listing" by Steven D. Singer.
The team combined ship logs and detail records from the two books to compile a comprehensive list of Spanish shipwrecks from 1495 to 1825. When combined with the Florida Key's tree-ring data from 1707 to 1825, they discovered that the figures matched. They also compared the data to the hurricane records from 1850 to 2009, and found that the figures and patterns also match.
The research was published in the journal Proceedings of the National Academy of Sciences on Monday.
It is important to study the relationship between climate change and hurricane variability as it could help in better emergency planning. Hurricanes from 1970 to 2002 in the U.S. alone have an accumulated damage that costs about $57 billion in 2015 dollar rates.