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The Enigmatic Glow of Milky Seas: New Insights from Research

For hundreds of years, sailors have recounted tales of vast glowing waters that are not merely fleeting flashes of luminescence but expansive illuminations that stretch across the horizon. Known as milky seas, these phenomena have puzzled both seafarers and scientists alike. Recent advancements in satellite technology and dedicated research efforts have started to unveil the secrets behind these captivating oceanic displays.

Milky seas are characterized by their consistent luminescence, which can cover areas as large as 100,000 square kilometers. Unlike transient bursts of light, these glowing seas can persist for days or even, on rare occasions, for weeks or months.

The origins of these vast glowing waters have remained elusive, largely due to their sporadic occurrence. The unpredictable nature of milky seas poses significant challenges for scientific investigation; researchers are often unable to predict when or how long they might last. To address this knowledge gap, scientists have collaborated to compile a comprehensive database aggregating data from centuries of sailors’ reports, satellite imagery, and documented occurrences of milky seas.

A research team from Colorado State University has meticulously gathered and analyzed 400 years of evidence, including firsthand accounts from mariners and relevant satellite observations. They endeavored to correlate these eyewitness testimonies with available images from maritime history while also considering climatic conditions present at the times of reported sightings.

Indian Ocean: The Milky Sea Hotspot

The findings indicate that milky seas are predominantly found in the Indian Ocean, especially in regions such as the Arabian Sea and Southeast Asia. Their formation appears to be influenced by significant climatic events, including the El Niño Southern Oscillation and the Indian Ocean Dipole, suggesting that while unpredictable, they may follow certain patterns influenced by environmental factors.

It is hypothesized that the glowing effect is primarily the result of bioluminescent bacteria, with Vibrio harveyi being a key player. In 1985, scientists aboard a research vessel collected water samples while traversing a milky sea, revealing that these luminescent bacteria had formed a coating on the algae present in the samples. Since that time, researchers have continued searching for similar samples to corroborate these findings.

“We strongly suspect — based on the characteristics of the light and how long it lasts — that it is bacteria,” stated Justin Hudson, the lead author of a recent study on the subject. He raised a compelling question: “How do you take some of the smallest organisms on Earth and have them engage in some behavior that’s half the size of the state of Colorado?”

Under optimal conditions, these bacteria seem to produce a shining film on the ocean’s surface. It has been observed that milky seas are most frequently reported near upwellings, which bring nutrient-rich water to the surface. However, despite the existence of similar upwelling regions worldwide, not all exhibit milky sea phenomena, leaving many questions about the underlying mechanisms unanswered.

Researchers are optimistic that the establishment of the new database will facilitate further exploration of milky seas and their implications on marine ecosystems.

“We have no idea what milky seas mean for the ecosystems they inhabit. They could signify either a thriving ecosystem or one under stress,” remarked co-author Steven Miller. “Having this data readily accessible will enable us to begin addressing questions about milky seas without relying solely on serendipitous encounters by passing ships.”

Source
explorersweb.com