Why the waters of Santa Barbara mysteriously turned turquoise: scientists discover that four years after the bewildering phenomenon, algae are the cause of a sudden color change
- Scientists say they have discovered the cause of a change in the color of water in California
- An algal bloom released calcium carbonate that distorts light
- The results were a turquoise-like turquoise shade off the coast of Santa Barbara
- These light-distorting flowers grew large enough to be seen from space
- A new method to study the algae can help to detect poisonous flowers preventively
Four years after coastal waters near Santa Barbara, California, inexplicably clear blue, researchers say they have determined the cause.
According to new research, the culprit behind the drastic and mysterious color change is one of & # 39; the smallest organisms in the world – a single-celled alga called coccolithophoren, originating from a large bloom.
In a paper published in the Journal of Geophysical Research: Oceans, scientists describe how the physical characteristics of the algae turned the otherwise dark blue waters into shades of turquoise.
After four years, scientists say they came to the bottom of the sudden clear blue water off the coast of California in the summer of 2015
& # 39; If the water off the coast of California starts to look like you're in the Caribbean, that's really weird & # 39 ;, said lead author Paul Matson, a postdoctoral student who worked on the research in a statement.
Unlike their algae family, diatoms coated in silica, coccolithophores, specifically a species called Emiliania huxleyi or E. hux, are wrapped in tiny dots of calcium carbonate.
Shedding these dots, the material interacts with the light to produce a light blue tint.
While the water-tinting algae observed by scientists are found most everywhere, the researchers say that algal blooms such as those causing the phenomenon are uncommon at latitudes such as those in Santa Barbara.
Algae blooms caused the introduction of calcium carbonate that distorts the light and changes the appearance of the water color. Above, E. huxleyi as seen through a scanning electron microscope
Part of what happened to the unusual was a large hot water formation, which researchers appropriately applied the & # 39; Blob & # 39; who entered the Northeast Pacific in 2013.
The waters remained in 2016, according to the researchers, and were linked to an El Niño weather event that further raised the water temperature.
Temperatures first rose and caused a bloom of the often toxic algae, Diatom, which feeds on silica, but when the diatoms burned their silicon reserves, E. hux, who didn't need the connection to survive, were ready to shine.
According to the researchers, the E. hux were fed with the dying diatom algae and exploded, growing large enough to be seen from space.
& # 39; We had this longer period in which we had extremely warm waters. We had low nutrient availability and weird things just happened, & Matson said.
The flowers became so large that they could be seen from space and were helped by the poisonous cousin of E. hux
Scientists could come to their conclusion with an innovative mix of satellite images and radar arrays that study surface currents to make maps of the algae every hour.
The new method can also detect where flowering is about to happen, giving them insight into how the algae started spreading in the first place.
They hope that the approach can be used to identify more harmful algal blooms in the future.
Flowers like diatoms that sweat from water bodies of nutrients and oxygen starve, are deadly to animals and also harmful to humans – algae can spread through the air and be inhaled unintentionally.
WHAT ARE THE RISKS OF ALGA FLOWERS?
Technically called cyanobacteria, the old class of organisms that create the flowers, are present almost everywhere where water is found, but thrive in warm, still bodies such as lakes and ponds.
They also create a unique class of toxins whose impact on humans is only partially understood.
Long associated with animal deaths, high doses of toxins in humans can cause liver damage and attack the nervous system.
In the largest outbreaks, hundreds of people have fallen ill from flowers in reservoirs and lakes, and officials in some areas are now routinely excluding water bodies used for recreation and warning after flowering.
But less is known about exposure at lower doses, especially in the long term.
Small studies have linked liver cancer exposure – one toxin is classified as a carcinogen and others have pointed to possible links with neurodegenerative disorders.
. [TagsToTranslate] Dailymail