Ocean Conservation & Tidalpunk

Retreating glaciers created 2,500km of “new” coastline and 35 “new” islands in the Arctic between 2000 and 2020, according to a new study.

The study: The Impact of Underestimated Southern Ocean Freshening on Simulated Historical Sea Surface Temperature Trend

cross-posted from: https://slrpnk.net/post/20111072

Canadian deep-sea mining firm The Metals Company (TMC) has announced it “initiated a process” with U.S. regulators to apply for both exploration and exploitation licenses, potentially circumventing the international regulator. TMC’s process with the U.S. National Oceanic and Atmospheric Administration falls under the Deep Seabed Hard Mineral Resources Act of 1980 (DSHMRA), which was established as an interim legal framework for the recovery of seabed mineral resources prior to the creation of an international regulatory framework under the United Nations Convention on the Law of the Sea (UNCLOS).

TMC made the announcement via a press release and a public-facing investor call just before the conclusion of the latest meeting of the 36-member council of the International Seabed Authority (ISA), the U.N.-affiliated regulator responsible for overseeing deep-sea mining in international waters.

Scientists explore a seafloor area newly exposed by iceberg A-84; discover vibrant communities of ancient sponges and corals.

Deep-sea ecosystems typically rely on nutrients from the surface slowly raining down to the seafloor. However, these Antarctic ecosystems have been covered by 150-meter-thick (almost 500 feet) ice for centuries, completely cut off from surface nutrients. Ocean currents also move nutrients, and the team hypothesizes that currents are a possible mechanism for sustaining life beneath the ice sheet. The precise mechanism fueling these ecosystems is not yet understood.

The world's oceans harbor a cultural heritage of sunken ships, remains of those lost in the transatlantic slave trade and Indigenous islanders' spiritual ties to the sea that must be protected, NGOs and native peoples say.

Archived version of the article: https://archive.is/PikWR

Mining companies are poised to mine the deep sea – but opposition is growing. What is the environmental cost, and are these metals actually needed?

On the west coast, local people have gone to court to try and force a rethink of the impacts of oil and gas exploration

Ocean literacy is the compass guiding us toward a sustainable future, empowering us to understand the risks and take meaningful action.

Ocean literacy is about how the ocean influences us and how we are influenced by the ocean.

We may have been taught that oceans are divided into named entities like the Atlantic or Pacific, but these are human constructs; the ocean operates as a single, interconnected system. Currents, warming, and marine species pay no heed to our geographic labels.

there cannot be a healthy planet without a healthy ocean

Abstract

The discharge of Fukushima radioactively contaminated water into the Pacific Ocean started in August 2023, posing comprehensive threats to marine ecosystems and human health globally. This study introduces the Fukushima Contaminated Water Risk Factor (FCWRF), which integrates three components─radionuclide diffusion, bioaccumulation, and global seafood trade─to evaluate the spatiotemporal distribution of risks based on actual discharge practices. Results suggest that comprehensive risks exceeding 2 orders of magnitude beyond the baseline will be transferred to six continents globally. Furthermore, the spread of such risks is projected to be six times faster than radionuclide diffusion. In the simulation, the results illustrated a small increase in radionuclide activity occurring in most regions of the Pacific Ocean. Nevertheless, the dimensionless FCWRF based on a novel integrated framework bridges the barriers among different fields in the risk assessment of radionuclides, thereby underpinning timely and effective responses from the global community.

cross-posted from: https://beehaw.org/post/18695339

A new study finds that even as mariculture expands globally, the industry could actually decrease its current biodiversity impact by 30%—if they get smarter about where they farm. But the same study also cautions that seafood farming in the wrong locations could just as easily ramp up current marine biodiversity impacts by over 400%.

One-fifth of the fish we consume is provided by farmed seafood, and that figure is only projected to rise as global demand for protein grows. The new research, published in Nature Ecology & Evolution, calculated that mariculture—the controlled production of shellfish, bivalves, and finfish in coastal areas and in the open ocean—will need to increase by 40.5% from 108,729 hectares to 152,785, to meet this growing demand by 2050.

Under a worst-case future scenario, where mariculture expansion occurred only in biodiversity-rich regions such as these, the effects could be profound: the cumulative biodiversity impact of seafood farming would increase by an average 270% at the country level, and by 420.5% at a global scale, compared to current impacts. Species-wise, the worst affected by mariculture under this extreme scenario would be large marine mammals including whales and seals, because these animals have considerable ranges that would overlap with more open-ocean farms.

But just as there’s a worst-case scenario, the researchers also posit a best-case scenario—one we could achieve, they say, if we take a more strategic approach.

“The best case scenario refers to all mariculture farms in 2050 [being] placed in sea areas with low [impact], including relocating existing farms and the new farms,” says Deqiang Ma, postdoctoral researcher at the University of Michigan School for Environment and Sustainability, and lead author in the new study. The model showed that if farms of the future were almost exclusively sited away from biodiversity hubs, the cumulative effects of mariculture would be on average 27.5% lower at the country level compared to 2020. Taken at the global scale, that equaled an impact reduction of 30.5%. Under this best-case future scenario, almost all marine species considered in the study would experience lower impacts compared to the current-day harms of seafood farms.

The annual competition draws thousands of entries from across the world and brings together images from below the water’s surface that show the diversity and challenges of subaquatic life

Despite their distinction as one of Earth's oldest lifeforms and the key role they play in sustaining coral reef ecosystems, marine sponges are vastly understudied.

Sponges are notoriously difficult to study, for a variety of reasons.

I’m campaigning for legal protection for cleaner fish, because no one has done a proper assessment of the impact of removing them from Scottish reefs