Hurricane activity of Little Bahama Bank over the last 700 years
I’m McKensie Daugherty, your host for on the ocean. Scientists predict the frequency of intense hurricanes will increase as Earth continues to warm. Records of hurricane activity are only available for the last 150 years, so current knowledge of the relationship between climate and hurricane activity is limited. Knowing how hurricanes behaved when the Earth’s climate was different than it is today may help scientists determine how changes in climate will affect the intensity of hurricanes in the future. In the Caribbean, flooded sinkholes, known as blue holes, collect sand that is washed in by strong hurricanes. Blue holes promote excellent sediment accumulation and preservation through time. Normally, the sediment that is deposited in the blue holes is fine-grain mud, so these sand layers serve as long-term indicators of hurricane activity. Texas A&M researchers are developing a hurricane record based on a 30-foot long sediment core from Thatchpoint Bluehole near Abaco Island in the Northern Bahamas. Sedimentation occurs at a rate of ½ an inch per year at the Thatchpoint Bluehole. The sediment record reaches 700 years into the past and has sand layers that correspond to ten of the twelve Category 2 or greater hurricanes that came within 30 miles of this site since 1866. Based on the Thatchpoint Bluehole sediment record, four active intervals of increased hurricane activity occurred near Abaco Island since 1200 AD. Further analysis of this record may provide new insights into the drivers of hurricane activity during the last millennium. This has been On the Ocean, a program made possible by the Department of Oceanography and a production of KAMU-FM on the campus of Texas A&M University in College Station. For more information and links, please go to ocean.tamu.edu and click “On the Ocean”.
Script Author: Tyler Winkler