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Mining For Answers: Is Deep Sea Mining Necessary in the Fight Against Climate Change?

By Sydney Hintz

Photo courtesy of PNAS


Wheels graze over the bumpy, unscathed terrain, exploring the new realm. The vessel scrapes against the seafloor, scattering the sediments into a dust that rises like the sun. It is in pursuit of something grand. No, not knowledge. Something far better: polymetallic nodules.


Deep-sea mining is the process of retrieving mineral deposits from the seabed. It is one of the limited ways to obtain rare metals like cobalt, nickel, manganese, copper and lithium. Mining is often paired with deep-sea drilling for oil and other natural resources, which are harvested by scraping the seafloor of the deep-sea in the pacific ocean’s nodules with large robotic vesicles. Nodules are smaller geographic regions with a high density of necessary metals, so mining these regions provides the greatest amount of material while minimizing damage.


An estimated 21 billion tons of polymetallic nodules rest in a single region of the Pacific Ocean, according to the US Geological Survey. These untapped deposits are essential in shifting from fossil fuel-powered vehicles to electric vehicles (EVs). The Metals Company, previously known as DeepGreen, sees the potential in polymetallic nodules and is at the forefront of deep-sea mining. There is a severe shortage of mineral deposits on land, with terrestrial resources already being exploited for industrial use. In order to produce the batteries necessary to shift gears to electric vehicles and renewable energy, more mineral deposits need to be extracted.


The first objective in the Objective Key Results (OKR) plan outlined in Speed & Scale: An Action Plan for Solving Our Climate Crisis Now by John Doerr, is electrifying transportation. Electric vehicles eliminate the carbon released from tailpipes, which is the largest emitter of carbon in transportation. By removing the tailpipe, massive progress will be made in reducing carbon emissions.


EVs were also ranked #26 in the top solutions to reduce greenhouse gas emissions in the New York Times Bestseller, Drawdown: The most comprehensive Plan Ever Proposed to Reverse Global Warming by Paul Hawken. Hawken notes that an average of 25 pounds of carbon dioxide emission is produced per gallon of gasoline, whereas electric vehicles boast an average of 12.2 pounds for 10 kilowatt-hours of electricity if charged from the pre-existing grid as of 2023 (EVs have the potential to become more efficient as the technology is refined). Switching from fossil-fuel powered vehicles to EVs reduces more than 50% of vehicle carbon emissions and is necessary to mitigate the effects of climate change. Climate scientists have come to the consensus that electric vehicles are the future, so why haven’t we started deep sea mining yet?


The deep-sea is one of the most elusive places on Earth, beaming with life that is waiting to be discovered. Deep-sea mining could drive marine life to extinction because of the invasive procedures to remove the material. “Each time a [deep-sea] expedition is launched to collect species, we find that between 70% and 90% of them are new to science,” says Sophie Benbow, the marine director at Fauna & Flora, an international wildlife charity. Much of those discoveries will be lost if we don’t take care.


Nodules take millions of years to form, and their rocky surfaces act as potential habitats for corals, sponges, nematodes, and other organisms. The extraction of nodules will permanently alter deep-sea ecosystems, and the large aquatic vessels that disturb the seafloor will wipe out all creatures that are unfortunate enough to fall in its path. The impact on biodiversity stretches far beyond the vessels’ line of fire. Kicking up silt and clay particles creates clouds in the water that inhibit vision and suffocate marine life, and dissolved metals and toxins from the mining sites act as a secondary threat to life. When the nodules are transported back to the ship, the remaining water is dumped back into the ocean, initiating a second wave of silt clouds which doubles the damage. The loud vessels also act as noise pollution that impacts marine mammal hearing and drown out intraspecies communication, resulting in a spike in dolphin and whale deaths. Most frightening of all, removing one animal or invertebrate from the food web could result in trophic cascades that cause ecosystems to fully collapse.


Deep-sea mining could also prove to be counterintuitive to electric vehicles’ goal of reducing the amount of carbon in the atmosphere, with the disruption of seafloor sediments releasing carbon back into the ecosystem. The ocean acts as the world’s largest carbon sink, storing away more emissions than the atmosphere and forests combined. The seafloor and sediments host the vast majority of this carbon, and disrupting the sediments will cause the carbon to reenter the ocean system and evaporate across the globe through the water cycle. While the amount of carbon released by mining disruption is small compared to the amount of carbon emissions that cars produce, it still goes against the mission of reducing carbon emissions that electric vehicles set out to achieve.


The cost-benefit analysis of electric vehicles is anything but simple. The mining required to obtain the necessary minerals for batteries violates human rights, destroys earth, and releases carbon on land. No matter which way you slice it, electric vehicles have serious drawbacks.


The complexities surrounding car production make it nearly impossible to have a truly “green” vehicle. Modern cars emit mass amounts of carbon dioxide and greenhouse gasses. Despite technological advances such as catalytic converters and improved gas mileage, they continue to cause extensive environmental damage. The trade-off between electric vehicles and deep sea mining is a microcosm of ongoing debates in the environmental sector surrounding climate solutions.


So, do we preserve biodiversity or reduce carbon emissions? What are we willing to compromise in pursuit of a greener future? How will we solve this climate crisis? Scientists and policymakers will have to dig deeper than the seafloor to get to the bottom of this issue.


 

Sources

“1.0 Electrify Transportation.” Speed & Scale, 14 Apr. 2023, speedandscale.com/okrs/1-0-electrify-transportation/.


Beiser, Vince. “The Mining Industry’s next Frontier Is Deep, Deep under the Sea.” Wired, 28 Feb. 2023, www.wired.com/story/deep-sea-mining-electric-vehicle-battery/.


“Deep Sea Mining Will Be Bad for Whales and Dolphins, Say Scientists.” BBC Newsround, 15 Feb. 2023, www.bbc.co.uk/newsround/64638528.


“Deep-Sea Mining.” IUCN, 7 July 2022, www.iucn.org/resources/issues-brief/deep-sea-mining.


Doerr, John E. Speed & Scale: An Action Plan for Solving Our Climate Crisis Now. Portfolio, 2021.


Gillespie, Alexandra. “Your next Car May Be Built with Ocean Rocks. Scientists Can’t Agree If That’s Good.” NPR, 3 Sept. 2021, www.npr.org/2021/09/03/1031434711/your-next-car-may-be-built-with-ocean-rocks-scientists-cant-agree-if-thats-good.


Hawken, Paul. Drawdown: The Most Comprehensive Plan Ever Proposed to Roll Back Global Warming. Penguin Books, 2018.


“Is Sustainable Mining Possible? The EV Revolution Depends on It.” The Washington Post, 22 Aug. 2022, www.washingtonpost.com/business/2022/08/11/electric-vehicle-nickel-mine/.

Libretexts. (2023, July 10). 19.3: Trophic Cascades. Biology LibreTexts. https://bio.libretexts.org/Courses/Gettysburg_College/01%3A_Ecology_for_All/19%3A_Food_Webs/19.03%3A_Trophic_Cascades

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