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Keeping Trash Out Of The Ocean | Earth Wise

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The Ocean Cleanup is a non-profit organization, founded in 2013 by Dutch inventor Boyan Slat, to develop and scale technologies to rid the world’s oceans of plastic.  It is an organization that proudly declares that its primary aim is to put itself out of business by successfully cleaning up the oceans.

A major activity of The Ocean Cleanup is efforts to clean the ocean garbage patches that have accumulated in several places, best-known of which is the Great Pacific Garbage Patch.  The effort involves use of large U-shaped floating barriers that act as an artificial coastline to trap garbage which is then funneled into a barge for disposal.  Ten full-sized systems will be needed to clean up the Great Pacific Garbage Patch.

A second activity of The Ocean Cleanup is preventing garbage in rivers from making its way into the oceans.  Rivers are the main source of ocean plastic pollution.  The Ocean Cleanup has developed river machines called Interceptors that capture garbage for disposal.  Last fall, they installed a machine called Interceptor 007 in Ballona Creek, a waterway in the Los Angeles area.  In the first rainfall after installation, the Interceptor managed to stop 35,000 pounds of waste from entering the ocean in just a few days.

The original Interceptor models have been deployed in Indonesia, Malaysia, the Dominican Republic, and Vietnam. A different type called the Interceptor Trashfence is being tested in Guatemala.

The Ocean Cleanup states that if fleets of its barrier systems are installed in all the garbage patches and Interceptors in the 1000 most significant rivers, 90% of floating ocean plastic can be removed by 2040.

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The Interceptor 007 Stops 35,000 Pounds Of Trash From Entering Ocean

The Ocean Cleanup

Photo, posted February 23, 2015, courtesy of Ministerie van Buitenlandse Zaken via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fitness Trackers For Lobsters | Earth Wise

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The lobster industry is somewhat unique, at least in this country, in that it involves an animal food that is kept alive until it has reached the destination where it will be consumed or used.  As a result, the industry has to deal with a problem they call “shrink”, which is the mortality lobsters experience as they change hands from capture to kitchen.

Maine’s lobster industry has reached out to the University of Maine Lobster Institute along with collaborators at other institutions to help quantify and mitigate stress points in the lobster supply chain that reduce survival and profitability.

A 2-year project was funded by the National Oceanic and Atmospheric Administration to create miniature sensory devices – crustacean heart and activity trackers (called C-HATs).  These are essentially Fitbits for lobsters.  The noninvasive devices strapped on a lobster monitor its heart rate and movement as it passes from trap to on-board live tank to live storage crate to truck to wholesaler to retailer or processor.

A separate sensor-equipped device called the MockLobster travels along with the lobsters to log environmental conditions experienced, including temperature, light and dissolved oxygen levels.

The hope is to be able to get a good handle on the conditions lobsters experience from trap to market and learn where problems are likely to arise.  The researchers are also working to develop economical, standardized protocols to monitor water quality and the heath of lobsters during their movement through the supply chain.

The goal is to produce big improvements in the bottom lines of everyone along the supply chain along with big improvements in the health of the lobsters destined for market.

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Fitness trackers, environmental sensors prototyped to improve survival in the lobster supply chain 

Photo, posted August 29, 2015, courtesy of Adam Grimes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

An Ecological Trap For Polar Bears | Earth Wise

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Climate change has been shrinking Arctic sea ice and this is causing changes in the behavior of polar bears.   The Southern Beaufort Sea, located where the northern edges of Alaska and Canada meet, is home to one of the 19 population groups of polar bears.  Historically, the polar bears in this region remained on sea ice year-round.  But in recent decades, about a quarter of them have chosen to come on land instead of staying on the shrinking summer ice platform.

A recent study by San Diego Zoo Global, the U.S. Geological Survey, and Polar Bears International looked at the energetic consequences of the bears’ behavior.  The decision of each individual bear to stay on the ice or move to land appears to be linked to the energetic cost or benefit of the choice.

Bears who moved to land expended more energy during the summer than bears that remained on the sea ice.  In late summer, as the ice became even more restricted, a greater amount of energy was expended by bears swimming to land.  So, the immediate energy cost of moving to land is much greater than remaining on the receding pack ice.

On the other hand, bears on land in this region have access to whale carcasses in the summer while bears on the sea ice appear to be fasting.  As a result, it may be the case that the declining population of bears in this region is in part caused by the ecological trap of bears staying on the ice to avoid expending all the energy needed to move to land.  The shrinking polar ice is a real problem for polar bears.

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Energetics Study Indicates that Shrinking Sea Ice Is Creating an Ecological Trap for Polar Bears

Photo, posted October 30, 2011, courtesy of Martin Lopatka via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Squid Skin Blanket

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Ultra-lightweight space blankets have been around for a long time.  Marathon runners wrap themselves in them to avoid losing body heat after a race.  They are very effective, but the amount of heat that they trap is fixed.  There is no way to regulate how much heat is trapped or released using a space blanket.

Researchers at the University of California, Irvine have developed a next-generation, adaptive space blanket that allows users to control their temperature.  The inspiration for the design was the skins of various species of squids, octopi and cuttlefish.  The ability of these aquatic creatures to camouflage themselves by rapidly changing color is due, in part, to skin cells called chromatophores that can instantly change from tiny points to flattened disks.

The Irvine researchers have developed a material that contains a layer of tiny metal islands that border each other.  In the relaxed state, the islands are bunched together, and the material reflects and traps heat, much like a conventional Mylar space blanket.  But when the material is stretched, the islands spread apart, which allows infrared radiation to go through and heat to escape.

The researchers envision many other applications for the novel material, including adaptable insulation for buildings and tents that can be adapted to different weather conditions.  There is even the possibility of clothing that can be adjusted to suit the comfort of each person.

The new material is lightweight, easy and inexpensive to manufacture, and is durable.  It can be stretched and returned to its original state thousands of times.  Some day we might all be wrapping ourselves in imitation squid skins.

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Squid skin inspires creation of next-generation space blanket

Photo, posted May 29, 2005, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Arguing Against Climate Change

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Most of the world has accepted the analysis of the overwhelming majority of climate scientists that shows that our planet is warming and that our actions are the primary cause.  However, some people – notably a number holding high office – reject this analysis.   What exactly does it imply to say that climate change is not happening or is not caused by us?

[Read more…] about Arguing Against Climate Change

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