Episode Details

 Big swaths of the Southern Ocean have been going green. Summertime “blooms” of the tiny plant-like organisms known as phytoplankton are covering a much larger area. That makes the ocean look greener. And that could be kicking off big changes in the life around Antarctica.

The trend started in 2016 and ’17. Before then, the sea ice around Antarctica had been pretty stable for years. But it decreased dramatically—disappearing across an area as big as Texas and New Mexico combined. And the ice has been dwindling ever since—a loss seen year ’round.

To understand how that’s affected life in the Southern Ocean, researchers looked at satellite photos. They studied the color of the ocean surface. Regions with more phytoplankton looked greener. On average, almost 70 percent of the study region showed a significant increase in summer phytoplankton over the past decade.

The researchers compared those findings to the numbers of tiny animals found in the water—krill and salps. Krill look like shrimp, and they’re a major food source for whales, fish, and other organisms. Salps have jelly-like bodies, and they’re not a major food source for any big ocean predators.

 The change in phytoplankton appears to be favoring the salps—they seem to like the regions with less ice and extra phytoplankton more than the krill do. But any long-term change in the balance between salps and krill could impact the entire ecosystem—a “green” conundrum in the Antarctic.

The post Going Green appeared first on Marine Science Institute. The University of Texas at Austin..