ocean floor

Fertilizing The Ocean | Earth Wise

January 23, 2023 By EarthWise Leave a Comment

There are a variety of schemes for removing carbon dioxide from the atmosphere. Some require advanced and generally not-very-well developed technology. Others, such as planting vast numbers of trees, are nature-based but are daunting with respect to the scale to which they need to take place in order to be truly effective.

Researchers at the Pacific Northwest National Laboratory in Richland, Washington have been examining the scientific evidence for seeding the oceans with iron-rich engineered fertilizer in order to feed phytoplankton. Phytoplankton are microscopic plants that are a key part of the ocean ecosystem.

Phytoplankton take up carbon dioxide as they grow. In nature, nutrients from the land end up in the ocean through rivers and from blowing dust. These nutrients fertilize the plankton. The idea is to augment these existing processes to increase the growth of phytoplankton. As they eventually die, they sink deep into the ocean, taking the excess carbon with them.

The researchers argue that engineered nanoparticles could provide highly controlled nutrition that is specifically tuned for different ocean environments. Surface coatings could help the particles attach to plankton. Some could be engineered with light-absorbing properties, allowing plankton to consume and use more carbon dioxide.

Analysis of over 100 published studies showed that numerous non-toxic, abundant, and easy-to-create metal-oxygen materials could safely enhance plankton growth. According to the researchers, the proposed fertilization would simply speed up a natural process that already sequesters carbon in a form that could remove it from the atmosphere for thousands of years. They argue that given the current trends in the climate, time is of the essence for taking action.

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Fertilizing the Ocean to Store Carbon Dioxide

Photo, posted August 2, 2007, courtesy of Kevin McCarthy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Offshore Wind | Earth Wise

November 16, 2022 By EarthWise Leave a Comment

California has tremendous potential offshore wind resources. The state set a preliminary target of 15 GW of offshore wind by 2045 earlier this year and may increase that number to 25 GW. But installing offshore wind on the West Coast is much more challenging than it is on the East Coast. The reason is that the ocean floor drops off rapidly on the Pacific Coast and it is simply not practical to attach wind turbines to the sea bottom. Instead, floating turbine technology will be required. That is more complicated and more expensive.

Despite the challenges, offshore wind in California is moving forward. The federal Bureau of Ocean Energy Management announced that the auction for rights to develop waters off central and northern California will be held on December 6. This will be the first wind auction ever along the U.S. Pacific Coast.

The auction will include three lease areas in the Morro Bay Wind Energy Area and two proposed areas in the Humboldt Wind Energy Area. Combined, the two areas cover over 370,000 acres and could potentially host over 4.5 GW of wind generating capacity. The projects developed in these areas are likely to become the first floating offshore wind projects in operation in the U.S.

Apart from the challenges of building floating wind installations, there will be the issue of the electric grid in the proposed regions being able to support the added generation from the wind farms. Substantial grid upgrades will be needed to accommodate all the power coming from the offshore facilities. In addition, California offshore wind projects will need to jump-start new supply chains in the U.S.

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Date is set for California offshore wind lease auction

Photo, posted March 24, 2016, courtesy of Andy Dingley / TEIA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting The Ocean Has Multiple Benefits | Earth Wise

June 21, 2021 By EarthWise Leave a Comment

An international team of authors from 18 institutions has recently published a paper in the journal Nature that offers a solution that addresses several of humanity’s most pressing problems at the same time. The paper provides a comprehensive assessment of where strict ocean protection can contribute to a more abundant supply of healthy seafood, help address climate change, and protect embattled species and habitats.

The study identified specific areas of the ocean that could provide all of these benefits if they were protected. Currently, only about 7% of the ocean is under any kind of protection. According to the study, if the appropriate 30% of the ocean was protected by the actions of the relevant countries by 2030, the cited benefits would be realized.

Safeguarding these regions would protect nearly 80% of marine species while increasing fishing catches by almost 9 million tons a year. It would also prevent the release of more than 1 billion tons of carbon dioxide by protecting the seafloor from bottom trawling, which is a widespread and destructive fishing practice.

Ocean life has been declining worldwide because of overfishing, habitat destruction, and climate change. The study pioneers a new way to identify the places that – if protected – will boost food production and safeguard marine life, while at the same time reducing carbon emissions. The study finds that countries with large national waters and large industrial trawl fisheries have the highest potential to contribute to climate change mitigation by protecting the carbon stored on the ocean floor. The ocean covers 70% of the Earth and its importance in solving the challenges of our time must not be underestimated.

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Three Times the Gains

Photo, posted January 10, 2016, courtesy of Hafsteinn Robertsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

June 4, 2020 By EarthWise Leave a Comment

Many of us are aware of the infamous ocean “garbage patches” of floating plastic. The Great Pacific Garbage Patch is roughly the size of Texas. But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total. The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around. One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor. This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets.

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents. These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity. Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom. As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Unconventional Fossil Fuel Source

October 16, 2017 By EarthWise Leave a Comment

It has only been about 10 years that fracking has been a big deal in the energy world. With it, a largely inaccessible source of fossil fuel became relatively easy pickings. And both the economic benefits and the attendant environmental problems have been grabbing headlines ever since.

Plastic In The Arctic

May 23, 2017 By EarthWise

On several occasions, we have talked about the enormous amount of plastic that litters the world’s oceans. Bits of bottles, bags, toys, fishing nets and other objects collect in gyres, or so-called garbage patches, which have grown and grown over the decades.