Woods Hole Oceanographic Institution & United States Geological Survey data shows how icebergs drifted more than 5,000km during the last glaciation
Woods Hole, MA (June 16,2021) -- Woods Hole Oceanographic Institution (WHOI) climate modeler Dr. Alan Condron and United States Geological Survey (USGS) research geologist Dr. Jenna Hill have found evidence that massive icebergs from roughly 31,000 years ago drifted more than 5000km (> 3,000 miles) along the eastern United States coast from Northeast Canada all the way to southern Florida. These findings were published today in Nature Communications.
Using high resolution seafloor mapping, radiocarbon dating and a new iceberg model, the team analyzed about 700 iceberg scours (“plow marks” on the seafloor left behind by the bottom parts of icebergs dragging through marine sediment ) from Cape Hatteras, North Carolina to the Florida Keys. The discovery of icebergs in this area opens a door to understanding the interactions between icebergs/glaciers and climate.
“The idea that icebergs can make it to Florida is amazing,” said Condron. “The appearance of scours at such low latitudes is highly unexpected not only because of the exceptionally high melt rates in this region, but also because the scours lie beneath the northward flowing Gulf Stream.”
Read more at: Woods Hole Oceanographic Institution
These 3D perspective views of the seafloor bathymetry from multibeam sonar offshore of South Carolina show numerous grooves carved by drifting icebergs. As iceberg keels plow into the seafloor, they dig deep grooves that push aside boulders and piles of sand and mud along their tracks. Sediment cores from nearby buried iceberg scours were used to determine when these icebergs travelled south along the coast. (Photo Credit: Jenna Hill, U.S. Geological Survey, Pacific Coastal & Marine Science Center)