Red Tides Are The Auroras of the Sea - Atlas Obscura
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Red Tides Are The Auroras of the Sea

A cloud of neon algae surrounds St. Matthew Island in the Bering Sea (Photo: NASA Goddard Space Flight Center/Flickr)

“Too much of a good thing” might be the most apt way to describe the beautiful environmental phenomena known as algal blooms, or “red tides.”

Usually materializing in spring and summer, these “blooms” are colorful underwater clouds of microscopic organisms that take advantage of surplus nutrients in the water. Occurring in both oceanic and freshwater bodies of water, red tides create gorgeous, swirling patterns in the water that look not unlike the auroras of the arctic, had they been dunked under the waves.

Unfortunately, red tides can devastate their surroundings. The dense algal build up can harm fish, and even larger beasts, like manatees. Microscopic organisms also struggle, since the algae end up hogging nutrients and oxygen. If they get bad enough they can even begin to grow huge, smelly piles of slime that will wash up on the beach. The EPA often refers to them as HABs, or Harmful Algal Blooms.

The causes of blooms vary—from excess fertilizer being dumped in the water, to naturally shifting currents, that put an flood areas with an excess of nutrients. But no matter how unwanted, the bloom are consistently gorgeous. Check out some of the best images we could find below. 

The coast of Estonia (Photo: Mapbox/Flickr)

The Swedish island of Gotland (Photo: NASA Goddard Space Flight Center/Flickr)

Lake Erie (Photo: NOAA Great Lakes Environmental Research/Flickr

Off the La Jolla, California coast (Photo: eutrophication&hypoxia/Flickr)

Off the coast of South Africa (Photo: NASA Goddard Space Flight Center/Flickr)

New Zealand (Photo: NASA Goddard Space Flight Center/Flickr)

Barents Sea (Photo: NASA Goddard Space Flight Center/Flickr)

Off the coast of Argentina (Photo: NASA Goddard Space Flight Center/Flickr)

The Sea of Marmara in Turkey (Photo: NASA Goddard Space Flight Center/Flickr)

Lake Ontario (Photo: NASA Goddard Space Flight Center/Flickr)

Bay of Biscay (Photo: NASA Goddard Space Flight Center/Flickr)

Barents Sea (Photo: NASA Goddard Space Flight Center/Flickr)

The Bay of Biscay (Photo: NASA Goddard Space Flight Center/Flickr)

The Gulf of Mexico (Photo: NASA Goddard Space Flight Center/Flickr)