Sandwiched between Florida and the Bahamas, the stretch of ocean is one of the best-studied marine environments in the world, yet it’s also the epicenter of an enduring geological mystery.
Since at least the 1930s, scientists in the region have noticed strange billowing white clouds looming in the turquoise calm of the water’s surface.
The strange phenomenon is called the “whiting event,” and scientists still don’t understand why it’s occurring in the Bahamas.
For researchers at the nearby University of South Florida (USF), it has become something of a “beluga whale.”
The baffling bright ocean patches are sometimes noticed in other oceans and lakes worldwide, but they appear more frequently than usual in the Bahamas.
Direct sampling of the turbid water indicates that it contains high concentrations of carbonate-rich particles.
Much of the Bahama Archipelago lies on a submerged carbonate platform known as the Bahama Banks. Does this mean that sediments are rising to the surface? Or could it be that phytoplankton blooms are actually producing the suspended material?
No one knows the answers to these questions, but USF scientists are determined to find out. They’ve used satellite imagery from NASA to show whiting events ebb and flow across the Bahamas.
The team doesn’t know if the identified trends are natural or man-made, but what they do know is that the magnitude of these whiting events from 2003 to 2020 appeared to correlate with the seasons.
The largest spots occurred from March to May and from October to December. On average, the white spots were about 2.4 square kilometers. On a clear-sky day, satellite images typically took about 24 of them, covering a total area of 32 square kilometers (12 sq mi).
However, between 2011 and 2015, the patches suddenly increased in size, covering more than 200 square kilometers of ocean (77 sq mi) at their peak. However, by 2019, the patches started shrinking again, although they never got quite as small as before.
The results suggest that a 10-year cycle may be at play. But a cycle of what exactly?
“I wish I could tell you why we saw this peak of activity, but we’re not there yet,” says USF oceanographer Chuanmin Hu.
“We see some interesting connections between environmental conditions such as pH, water salinity and the behavior of winds and currents, but we cannot yet say which exact mechanical, biological or chemical processes were responsible for this peak in activity.”
More direct field experiments are needed, and not just in the Bahamas. Comparing whiting events in other regions could help scientists identify what traits they share.
USF researchers tested their model on whiting events in the Big lakes with preliminary success, but now have to substantiate these patterns on the ground or in the water.
August 2 Satellite view of the Pyramid Lake Whiting event in its early stages pic.twitter.com/SoPltG1lG3
— Pyramid Lake Paiute Tribe (@plpt) August 10, 2020
some studieshave shown, for example, that whiting events occur more frequently in locations with muddy sediments.
In addition, some marine conditions may favor the suspension of sediments and calcium carbonate in the water column. As previously mentioned, recent satellite data suggests white spots are more common in the Bahamas during spring and winter, and that’s when the north-south Florida currents alternate.
Without further evidence, all of these theories will remain just that.
The study was published in remote sensing of the environment.
