removal

Rigs To Reefs

March 29, 2019 By EarthWise Leave a Comment

There are about 6,000 offshore oil platforms in the world’s oceans. They have an immense presence physically, financially and environmentally. As these massive structures extract hydrocarbons from deep beneath the sea, they also undergo a remarkable transformation under the water. The enormous substructures that support the platforms become vertical reefs, home to millions of individual plants and animals.

Over time, many oil platforms are decommissioned, and their owners are faced with the choice of either removing them entirely or transitioning them into permanent reefs. Traditional practice was to restore the site to its original condition, but more recently the idea of “reefing” old platforms has gained popularity. As of 2016, more than 11% of decommissioned platforms in the U.S. portion of the Gulf of Mexico have become permanent reefs.

Decommissioning and completely removing a platform is a daunting and pricey proposition. The most recent estimate for removing all platforms off the coast of California alone totals $8 billion. Modifying the platforms to serve as permanent reefs cuts these costs significantly, especially those associated with hauling, cleaning and disposing of the underwater support structure, which will have thousands of tons of sea-life clinging to it by the time it is removed.

Converting the structure into a permanent reef means making it free of any hydrocarbons or other hazardous materials. But this is still a far cheaper venture than total removal. Studies of oil rigs as underwater habitats have shown them to be some of the most productive in the world. They are 3-dimensional reefs whose open construction allows currents to pass through bringing lots of nutrients.

Over time, more and more oil platforms will be decommissioned. Many may end up remaining as permanent homes for undersea life.

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Rigs to Reefs

Photo, posted August 21, 2011, courtesy of Marianne Muegenburg via Flickr

Earth Wise is a production of WAMC Northeast Public Radio.

Can We Remove Enough CO2 From The Air?

January 9, 2019 By EarthWise Leave a Comment

As atmospheric carbon dioxide levels continue to set new records and the effects of climate change grow stronger, humanity has continued to procrastinate on reducing emissions. As a result, it is increasingly clear that any strategy to avoid runaway climate change will have to involve the use of “negative emissions”- techniques or technologies that actually remove CO2 from the air.

There are both low-tech and high-tech methods for removing carbon dioxide from the atmosphere and both are likely to be needed.

On the low-tech side, afforestation (planting trees where there were none before), reforestation, changes in forest management, rebuilding the carbon backbone in agricultural soils, and the use of energy from waste biomass are all ways to take carbon out of the atmosphere.

On the high-tech side, direct air capture technologies that take CO2 out of the air and store it in the ground are making rapid progress. Right now, they are still very expensive,but that is changing. There is an analogy to wind and solar technology. Not very long ago, both of those technologies were quite expensive but now their costs have plummeted to the point where they are often the cheapest way to make electricity. With sufficient development effort and deployment, direct air capture technology could become quite affordable.

Some people advocate geoengineering as a solution for climate change. While removing carbon dioxide amounts to tackling the root cause of the warming climate,geoengineering would address the problem by changing the climate again in some other way. It is at best an extremely dangerous approach.

Removing CO2 using a combination of natural and man-made techniques is an important part of mitigating the effects of climate change.

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Climate Solutions: Is It Feasible to Remove Enough CO2 from the Air?

Photo courtesy of Climeworks.

Earth Wise is a production of WAMC Northeast Public Radio.

Reviled Animals Can Be Beneficial

February 16, 2018 By EarthWise Leave a Comment

Predators and scavengers are widely persecuted by people because they are often harmful to property, livestock, and human beings. Nonetheless, research has shown that many of these animals play important roles in ecosystems and their removal can be quite harmful.

Removing Heavy Metals From Water

September 7, 2017 By EarthWise

Clean and abundant water is the most essential need for all human societies and the supply of it is threatened by increasing populations and volatile climate patterns. The quality of water is threatened by a host of contaminants, most of our own making.

A CO2 Vacuum Cleaner

July 13, 2017 By EarthWise

A new carbon capture plant, sitting on top of a waste incineration facility near Zurich, Switzerland, is now sucking CO2 out of the air to sell to its first customer. The plant opened on May 31, and is the first commercial enterprise of its kind.

[Read more…] about A CO2 Vacuum Cleaner

Dying California Trees

December 16, 2016 By EarthWise

California’s trees are dying. According to the U.S. Forest Service, more than five years of drought in California has left 102 million dead trees across 7.7 million acres of forest. In fact, 62 million trees have died this year alone – a 100% increase from 2015.

A Giant Dam Removal Project

May 30, 2016 By WAMC WEB

In early April, the U.S. Government, the states of Oregon and California, and the utility Pacificorp signed an agreement that will lead to the removal of four dams on the Klamath River by 2020, amounting to one of the largest river restoration efforts ever undertaken in the United States.