This week, I had the pleasure of hearing Dr. Patricia Yager from the University of Georgia speak at the University of Rhode Island’s Graduate School of Oceanography. Afterward, I was invited to a delightful dinner with Dr. Yager and other Antarctic researchers including Dr. Tatiana Rynearson, Dr. Bethany Jenkins, and Dr. Brice Loose. Dr. Yager spoke about climate change in Antarctica and specifically about the Amundsen Sea polynya.
A polynya (pol-IN-ya) is an open area of water within sea ice. The Amundsen Sea polynya is an annually reoccurring polynya, which has glacial ice (ice flowing off the continent) on one side and pack ice (sea ice) on the other. In winter, it is kept open by the fierce katabatic winds blowing off the continent of Antarctica, and during warmer months, the polynya increases in size as the pack ice melts.
Since a polynya is an open area of water, it is an area of high productivity—meaning it has high levels of phytoplankton growth. Phytoplankton are tiny plants and the base of the marine food chain. During the summer months, when the sun never sets, phytoplankton growth is exponential—resulting in a phytoplankton bloom. The Amundsen Sea polynya is the most productive area around Antarctica, and Dr. Yager said she has never seen such green, thick, soupy water than there.
Among other things, Dr. Yager studies the relationships between iron, nitrates, and phytoplankton growth in environments with increasing ice melt, which has implications for carbon sequestration (storing of carbon, which helps reduce global warming and climate change). Like other plants, phytoplankton take up carbon dioxide–a major greenhouse gas—during photosynthesis, and phytoplankton blooms act as carbon sinks, pulling massive amounts of carbon dioxide from the atmosphere.
Dr. Yager noted that this area is losing ice—and fast. The West Antarctic Ice Sheet and its glaciers are melting rapidly. This rapid melting and greater than usual influx of fresh water is causing changes to the ecosystem. Sea ice surrounding the polynya is also decreasing.
You can learn more here.
In ice news:
Waters surrounding Greenland are losing salinity (saltiness) due to the melting of freshwater glaciers diluting the sea water around. In turn, this may affect marine life in these environments (just as is occurring in the Amundsen Sea).
Sea ice in the Arctic is now about 2 million square km below the 1981-2010 median.
Antarctic sea ice is around 200,000 square km below the 1981-2010 median.
Upwelling (the flow of warm water toward the surface) is thought to have caused recent ice shelf collapses and glacial thinning.
Environmental groups and officials met in Australia this week to discuss the formation of a new marine sanctuary in Antarctic waters.
New imagery captured on Thursday shows the cracks in the massive B-44 iceberg, which calved from the Pine Island glacier back in September.
Here’s a cool gif of that breakup in action.
Sea ice moves and flows. Check out this drifting of the massive Weddell polynya.
New Zealand glaciers have lost more than 25% of their ice since 1977.
Check out the Daily Glacier Bot and watch glaciers melting over time.
Our beautiful and essential ice is melting. Meanwhile, NOAA reported this week that so far, 2017 is the second warmest year on record.
As always, I am not a scientist, just a writer/illustrator and science communicator passionately in love with sea ice. I welcome input and corrections by polar scientists as I learn more about this remarkable and vital part of our planet and bring this knowledge to a wider audience.
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