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As the U.S. heads toward a summer heat wave, we start off with something chilly, before heading to the tropics and on to the frontiers of AI. Have a great Fourth of July and see you on July 5.
A view of the Barents Sea near the settlement of Teriberka on the Arctic coast of northwest Russia. Photo: Lev Fedoseyev/TASS via Getty Images
The Arctic Ocean's boundaries are getting fuzzier as Atlantic waters push further northward and sea ice thins and melts more with each passing year, a new study finds.
Why it matters: If this trend continues, it could have wide-ranging impacts on lucrative fisheries, such as cod. It may already be altering weather patterns.
The basics: The Atlantic Ocean is well-mixed, with salty waters throughout the water column. In contrast, Arctic waters have clearly separated layers — on top there is freshwater, which can be cooled down in the fall to form sea ice, and then replenished in the spring and summer, when the sea ice melts.
The boundary between the Arctic Ocean and the Atlantic Ocean is defined by this physical difference, said the study's lead author Sigrid Lind of the Institute of Marine Research in Norway.
What they did: Researchers deployed sensors from ships to extend a long-running set of observations of the entire Barents Sea.
What they found: The regional "hot spot" of warming is related to an oceanic invasion — the Atlantic Ocean is pushing farther north and east as the Arctic Ocean retreats.
Go deeper: Read the whole story in the Axios stream.
Aerial view of deforestation in the Western Amazon region of Brazil on September 22, 2017. Photo: Carl De Souza/AFP/Getty Images
Last year saw the second-largest tropical tree cover loss on record since 1999, in large part because of human-caused fires in the Amazon, a new analysis from the World Resources Institute and University of Maryland found.
What it means: Trees absorb huge amounts of carbon dioxide, preventing even more global warming. Losing tree cover means there's the potential for accelerating warming, as well as a range of other effects, including damage to biodiversity, the loss of livelihoods for indigenous populations and greater susceptibility of the tropics to drought.
What they found: Using satellite data, the team found the tropics lost 15.8 million hectares, or 39 million acres, of tree cover in 2017. It's the equivalent of losing 40 footballs fields of trees a day for an entire year, researchers found.
Keep in mind: Tree cover loss is not the same as deforestation. Instead, it means the removal of tree canopy due to human and natural causes, and includes trees in plantations as well as natural forests.
Yes, but: The biggest contributor to forest cover loss is the clearing of forests for agriculture and other human uses.
Go deeper: Read the whole story in the Axios stream.
An AI-generated graphical representation of a movie script. Image: Rivet.ai
A new company wants to help people make movies by outsourcing the grunt work — scheduling, budgeting, script analysis — to AI, Axios' Kaveh Waddell writes.
Starting from a human-written script, its algorithms can draft a budget and a shooting schedule, and even look for plot holes.
Why it matters: Debajyoti Ray, the founder of Rivet.ai, says that AI tools can cut down on uncertainty and allow production companies to take bigger risks.
Rivet.ai spun out of End Cue, the production company behind a trippy, nonsensical AI-written short film called Sunspring. Ray, whose background is in natural language processing, said his philosophy changed after Sunspring: His new company is focused mostly on analyzing human writing rather than trying to emulate it.
How it works:
Go deeper: Read the rest of Kaveh's story.
Artist impression of the interstellar comet ‘Oumuamua. Image: ESA
Satellite image showing estuaries along the coast of Guinea-Bissau on May 17, 2018. Image: NASA Earth Observatory
NASA released this image, showing estuaries near the coast of Guinea–Bissau in Africa, back on May 17. To me, this looks like a painting, complete with cerulean hues.
Here's NASA's explanation, posted at the agency's Earth Observatory website — a wormhole of a website for Earth science enthusiasts:
Estuaries near the coast of Guinea–Bissau branch out like a network of roots from a plant. With their long tendrils, the rivers meander through the country’s lowland plains to join the Atlantic Ocean. On the way, they carry water, nutrients, but also sediments out from the land.
The natural-color image shows the sediments as the rivers flow from east to west, with the discoloration at its maximum in Rio Geba, which runs past Bissau, the country's capital.
The flat terrain in this small west African country is ideal for farming, particularly for rice cultivation, NASA writes. But land used for growing rice comes at the expense of protective mangroves, which form a buffer between the rivers and the lands. Erosion is now a problem along the Rio Geba, according to NASA, as is the issue of agricultural runoff into the water.
Who knew that erosion and runoff sediments could be so beautiful?