Hi everyone, I’m Dr. Boisvert! Today I want to talk to you about the parts of the #ocean that freeze over, like this sea ice just outside of Thule, Greenland in the Arctic taken during an Operation #IceBridge campaign in 2016. 🧊🧊🧊🧊#WorldOceansDay
The seas in the mid-Atlantic and the Arctic are very different, but they’re part of the same global ocean! Here’s me ‘floating’ on sea ice off the coast of Greenland in 2016 and me again floating on Ocean City Beach in Maryland last weekend. 🧊🧊🧊🌊🌊🌊#WorldOceansDay
In the Arctic the ocean is cold enough (-1.8ºC🥶) to freeze saltwater and create sea ice. But here in the mid-Atlantic, the ocean is much warmer thanks to a massive current known as the Gulf Stream, which transports heat from the tropics.🌴🌎🌴 #WorldOceansDay
Temperatures in the Arctic Ocean are warming faster than anywhere on Earth, and less sea ice is surviving during the summer months. These changes could alter ocean currents and temperatures all throughout the planet, including here in Maryland 🌊🌡️🌊#WorldOceansDay
Since sea ice is bright white, it reflects most of the solar radiation back into space during the summer ☀️☀️☀️. When the ice melts, the exposed dark ocean absorbs more of this incoming solar radiation, which warms the ocean and melts more ice. #WorldOceansDay
Sea ice also inhibits the interaction between the atmosphere above and the ocean below ☁️🌊☁️🌊 . Here’s a picture I took in 2016 of an opening in Arctic sea ice that led to increased evaporation from the ocean and these low/wispy clouds. #WorldOceansDay
The ocean freezes over in the Southern Ocean surrounding Antarctica as well🇦🇶. But until recently, Antarctic sea ice had actually been increasing. #WorldOceansDay
Still, satellite observations show global sea ice totals have moved consistently downward over 38 years. Antarctic trends are more muddled, but they do not offset the great losses in the Arctic. 🛰️🧊🌍#WorldOceansDay
Hope you enjoyed learning some about our frozen ocean regions! Happy #WorldOceansDay everyone, and have an ‘ice’ day! 🌎🌊🧊🛰️☁️☀️🌨️
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These images may look otherworldly, but they don’t show icy exoplanets. These gorgeous photos of Earth’s polar ice come from NASA's Operation #IceBridge—and while the mission officially ended last week, you can still explore more high-def images @NSIDC: nsidc.org/the-drift/data…
Summer melting exposes ice layers thousands of years old along the edge of Humboldt Glacier in northwest Greenland. Glaciers consist of snow that has been transformed into thick ice layers and flowed downhill, where it’s often exposed at the edge.
An iceberg surrounded by sea ice floes off the coast of Wilkes Land, East Antarctica. Operation #IceBridge data helps scientists study the height, thickness and topography of sea ice in the polar seas. Icebergs calve off land ice, and sea ice forms by freezing ocean water.
With data from a rare expedition to Greenland, researchers are shedding more light into the complex subglacial processes that control how fast glaciers slide toward the ocean and contribute to sea level rise. go.nasa.gov/2PY0oCG
Researchers camped on the surface of Russell Glacier to study how its sliding velocity changed in response to meltwater that drains down to the bottom of the ice
At the edge of the ice sheet, where glaciers melt constantly, meltwater rushes everywhere through an intricate system of lakes and streams. Some of those streams thunder off into sinkhole-like structures called moulins, which funnel water downwards.