Satellite images show splashes of milky white water surging across the pristine blue waters of the Bahamas. Although this phenomenon has been reported for nearly 100 years, scientists still have no idea what actually causes it.

The Landsat 8 satellite captured the natural color image (above) of a whiting event along the west coast of Great Bahama Bank on April 4, 2015. This whiting event was large and lasted around two months before disappearing, but the events can last between a few days and three months.

Water clouds are known to be the result of fine particles of calcium carbonate suspended in water. However, it is unknown what causes the clouds to emerge in the water.

Some claim it to be a mechanical process, like calcium carbonate being lifted from the sea floor of the carbonate platform, while others believe it could be the result of phytoplankton blooms and others biochemical processes.

“In reality, there is no scientific consensus on what causes them,” Chuanmin Hu, an oceanographer at the University of South Florida, said in a statement.

To shed light on this mystery, Hu and other scientists at the University of South Florida studied thousands of satellite images of the Bahama Banks collected between 2003 and 2020 using machine learning intelligence. in depth.

They found there was huge variation in the size of individual whiting patches, ranging from 100 square meters (1,076 square feet) to 226 square kilometers (87 square miles), with the average size being 2.4 kilometers. square (0.9 square miles). .

This variation observed in the Bahamas could also follow a kind of cycle. In 2003, the average whiting event covered 25 square kilometers (9.6 sq mi), but in 2014–2015 it averaged 350 square kilometers (131 sq mi). The latest results for 2020 show the average has returned to 25 square kilometers (9.6 square miles).

Crucially, the research also revealed that the emergence of white clouds was closely associated with seasons, as many more events occurred in spring and winter.

This seasonality could be an important clue in the mystery. This perhaps suggests that weather and environmental conditions play a role. However, for now, scientists are still puzzled.

“I wish I could tell you why we’ve seen this spike in activity, but we’re not there yet,” Hu added. “We see interesting relationships between environmental conditions, such as pH, water salinity, and the behavior of winds and currents, but we can’t yet say what exact mechanical, biological, or chemical processes were responsible for this. Ultimately, we need to do more field experiments and combine them with remote sensing research like this to better understand formation processes.

The new study was recently published in the journal Remote Sensing of Environment.

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