Tag: Southern Ocean

Climate: Antarctic icebergs seen as key carbon sinks

Southern Ocean sequesters up to 10 percent of global carbon

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Giant Southern Ocean icebergs are key links in the carbon cycle, according to a new study. @bberwyn photo.

Staff Report

A new study by the University of Sheffield’s Department of Geography helps confirm the importance of giant Antarctic icebergs as key pieces in the global carbon cycle. The findings were published this week in Nature Geoscience.

The trails of fresh water from the melting slabs of ice contain iron and other nutrients, supporting unexpectedly high levels of phytoplankton growth, the study found.That biological activity, known as carbon sequestration, contributes to the long-term storage of atmospheric carbon dioxide, helping to slow global warming. In all, icebergs may responsible for storing up to 20 percent of carbon in the Southern Ocean, the researchers concluded. Continue reading “Climate: Antarctic icebergs seen as key carbon sinks”

Environment: Is climate change to blame for giant petrel decline in South Orkney Islands?

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The Southern Ocean’s pelagic birds may be vulnerable to global warming changes like melting sea ice. @bberwyn photo.

Study tracks sudden drop in numbers at important breeding site in Southern Ocean

Staff Report

Scientists with the British Antarctic Survey reported a big drop in the population of giant petrels at an important breeding site in the South Orkney Islands, northeast of the Antarctic Peninsula.

The long-term study found cyclical fluctuations in breeding success, showing that the birds defer breeding in less than optimal conditions. But the drop in numbers the past 10 to 15 years is alarming, according to the findings published in the journal Polar Biology online. Continue reading “Environment: Is climate change to blame for giant petrel decline in South Orkney Islands?”

Environment: Some countries only paying lip service to Antarctica conservation

Legal analysis finds some countries are abusing an international conservation treaty to justify more Southern Ocean fishing

Increasing concentrations of CO2 could turn this Antarctic beach into a tropical zone. Photo by Bob Berwyn.
Will the world be able to agree on new protection for the Southern Ocean? @bberwyn photo.

Staff Report

Efforts to set aside protected ocean areas around Antarctica are faltering because some countries are willfully misinterpreting a legal treaty governing the use of resources in the region, according to a new analysis published in the journal Marine Policy.

At issue is the term “rational use” in an international treaty that governs the management of natural resources in the region. Even though the treaty is focused on conservation, some countries are twisting the term to justify unsustainable fishing, said the scientists and legal scholars who published their findings to coincide with a meeting of the Commission for the Conservation of Antarctic Marine Living Resources in Hobart, Tasmania.

The international organization is setting fisheries management rules for the Southern Ocean around Antarctica and also wants to take up the issue of creating vast new marine reserves — but those efforts have been blocked in recent years by Russia and China, who want the freedom to exploit resources unsustainably.

The treaty requires that fishing does not cause irreversible damage to the greater marine ecosystem. While defined in the text of the legal Convention, the term rational use is increasingly being interpreted to mean an unfettered right to fish. Even more surprising, countries such as China and Ukraine have recently invoked rational use to protest the adoption of marine protected areas in the Southern Ocean.

“Our research into the treaty negotiation record shows that ‘rational use’ on its own did not have a clear, consistent, or objective meaning,” said lead author Jennifer Jacquet, an assistant professor in New York University’s Environmental Studies Program.

“In recent years, some countries have argued that MPAs interfere with their right to rational use,” Brooks said. “Yet adopting MPAs in CCAMLR waters is in complete accordance with stipulations of rational use, which require conservation of the fished species and the greater ecosystem in the Southern Ocean.”

Currently, the main species harvested in the Antarctic are Antarctic krill and Patagonian and Antarctic toothfish, also known on the market as the lucrative “Chilean sea bass.”

“The Southern Ocean is a global commons. As such, marine protected areas would allow CCAMLR member states to continue fishing while also ensuring a legacy for future generations,” Brooks said. “What could be more rational than that?”

Climate: Melting Antarctic glaciers may boost ocean food chain

Study explores Southern Ocean nutrient cycle

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Between hunts, a leopard seal snoozes on an ice floe in a polynya near the Antarctic Peninsula. @bberwyn photo.

Staff Report

FRISCO — Melting Antarctic glaciers are adding nutrients to the Southern Ocean, potentially boosting the entire food chain. The Southern Ocean could become a more productive ecosystem as a result of climate change, scientists suggested in a new study accepted for publication in Journal of Geophysical Research: Oceans, an American Geophysical Union journal. Continue reading “Climate: Melting Antarctic glaciers may boost ocean food chain”

Study eyes role of plankton in cloud formation

Southern Ocean research shows how plankton emissions brighten clouds

Clouds over Antarctica. @bberwyn photo.
Clouds over Antarctica. @bberwyn photo.

Staff Report

FRISCO — Swarms of tiny plankton may play a bigger role in cloud formation than previously realized, scientists said after studying the Southern Ocean.

The new research shows that plankton produce airborne gases and organic matter to seed cloud droplets, which lead to brighter clouds that reflect more sunlight. Continue reading “Study eyes role of plankton in cloud formation”

Report shows growing impacts of ocean acidification

CU-Boulder scientists study document decline of calcification rates in marine organisms around Antarctica

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The Southern Ocean may lose its ability to function as a carbon sink. bberwyn photo.

Staff Report

*More Summit Voice stories on ocean acidification

FRISCO — The steady increase of atmospheric carbon dioxide is already causing large-scale shifts in the ocean carbon cycle, according to University of Colorado, Boulder scientists, who calculated the calcification rate of marine organisms in the Southern Ocean.

According to the scientists there has been a 24 percent decline in the amount of calcium carbonate produced in large areas of the Southern Ocean over the past 17 years. Continue reading “Report shows growing impacts of ocean acidification”

Study tracks blue whales across Southern Ocean

New data will help shape conservation efforts in the waters around Antarctica

Naval training exercises off the coast of California could pose a threat to endangered marine mammals.
Australian and New Zealand researchers have tracked blue whales across thousands of miles in the Southern Ocean to help inform conservation efforts. Photo courtesy NOAA.

Staff Report

FRISCO — As a keystone species in marine ecosystems, blue whales have a significant impact in the ocean around Antarctica, but the population dynamics of the species in the region are still a mystery as the marine mammals recover from the decimation of the whaling era.

That may change following the recent six-week Australia-New Zealand Antarctic Ecosystem Voyage voyage, as researchers tracked the world’s largest creatures across thousands of miles of ocean, detecting their songs from as far as 750 kilometers away. Continue reading “Study tracks blue whales across Southern Ocean”