greenhouse gases Archives - Saving Seafood

Our View: We must have a say in offshore wind plans

June 30, 2022 — Few dispute the need to develop alternative ways to generate electricity that don’t produce greenhouse gases, but our response to a proposed floating offshore wind farm in Washington state isn’t a straightforward “yes.”

Similar complications arise regarding floating wind turbines off the southern Oregon Coast. These prompted the Astoria City Council and the Port of Astoria Commission to recently ask the federal Bureau of Ocean Energy Management and the Oregon Department of Energy to take their time before granting permission. Local officials want a demonstration project before grander plans are authorized, along with a full-scale environmental impact analysis.

In Washington state, the development being pursued by Seattle-based Trident Winds is generating misgivings among some users of offshore waters, who fear the wind farm located about 45 miles west of the mouths of Willapa Bay and Grays Harbor — and the cables linking it to the shore — could be one more blow to fisheries and the environment.

To put these concerns in a historical context, hydropower development in the 20th century in the Columbia River watershed came with many promises about preserving salmon runs and small-town economies. We all know how that turned out.

Read the full story at The Daily Astorian

Leaving more big fish in the sea reduces CO2 emissions

October 29, 2020 — An international team of scientists has found leaving more big fish in the sea reduces the amount of carbon dioxide (CO₂) released into the Earth’s atmosphere.

When a fish dies in the ocean it sinks to the depths, sequestrating all the carbon it contains with it. This is a form of ‘blue carbon’—carbon captured and stored by the world’s ocean and coastal ecosystems.

“But when a fish is caught, the carbon it contains is partly emitted into the atmosphere as CO₂ a few days or weeks after,” said Gaël Mariani, a Ph.D. student at the University of Montpellier in France.

Mr Mariani led a world-first study showing how ocean fisheries have released at least 730 million metric tons of CO₂ into the atmosphere since 1950. An estimated 20.4 metric tons of CO₂ was emitted in 2014—equivalent to the annual emissions of 4.5 million cars.

Read the full story at PHYS.org

Climate Change Is Already Reshaping Commercial Fishing

March 26, 2019 — The ocean has been steadily warming over the past 100 years, absorbing most of the heat trapped by atmospheric greenhouse gases. Unless we swiftly and dramatically reduce greenhouse gas emissions, the ocean could warm by as much as 4°C in the next 80 years. This puts fish and the people they feed and employ in hot water. Half of the planet relies on fish as a vital source of protein, and the fishing industry employs more than 56 million people worldwide.

Understanding where and why fisheries have been impacted by warming is necessary to ensure that the ocean remains a source of both nutrition and prosperity. In a study published in Science, I, along with colleagues from Rutgers University and the U.S. National Oceanic and Atmospheric Administration, show that ocean warming has already hurt fisheries’ ability to provide food and support livelihoods around the globe.

Fisheries are like a bank account, where we live off the interest. If fishing reduces the principal too much, the interest is lowered. Similarly, if the environment reduces the interest rate, the interest is also lowered. We combined maps of historical ocean temperature with estimates of historical fish abundance to see how warming has affected the interest rate and returns from the global fisheries bank account.

Fish don’t want their water too hot or too cold. As the ocean warms, they move poleward and into deeper water to follow their preferred temperatures. The impacts of these shifts are complicated; depending on the species, ocean warming and its knock-on effects can either increase or decrease the habitat available to fish. This can either increase or decrease the availability of important species in the food chain. Thus, ocean warming might benefit some fish populations while hurting others.

This is what we found in our research. Although warming has benefited some fisheries, it has hurt others. The losers outweighed the winners, resulting in a net 4% decline in sustainable catch potential over the last 80 years. Four percent might sound small, but it represents a loss of 1.4 million metric tons previously available for food and income.

Some regions have been hit especially hard. The North Sea, which supports large commercial fisheries for species like Atlantic cod, haddock, and herring, has experienced a 35% loss in sustainable catch potential since 1930. The waters of East Asia, neighbored by some of the fastest growing human populations in the world, have seen losses of 8% to 35% across three seas.

Read the full story at Baron’s

Trump Administration Report Recommends Reducing Greenhouse Gas Emissions To Protect Oceans From Climate Change

November 27, 2018 — The Fourth National Climate Assessment is a landmark report that was published last week on the day after Thanksgiving. It summarizes the impacts of climate change in the United States as well as potential mitigation and adaptation measures. The report states that the combined effect of burning fossil fuels, developing natural landscapes, and deforestation have increased the concentration of greenhouse gases (GHGs) in Earth’s atmosphere* and emphasizes that drastically reducing GHGs is necessary to prevent the most catastrophic consequences of climate change.

According to the report, climate change is modifying the ocean environment in three primary ways: warming, oxygen loss, and acidification. These “stressors” have large implications for ocean ecosystems and marine fisheries. Globally, ocean surface temperatures have increased by nearly 1.3°F over the past century and “… more than 90% of the extra heat linked to carbon emissions is contained in the ocean.” As the ocean warms, seawater not only expands and causes sea levels to rise, but it also loses its ability to hold gases – including oxygen. Additionally, as carbon dioxide (CO2) emitted by human activities dissolves in seawater, it undergoes a series of chemical reactions that are gradually causing the ocean to become more acidic.

While warming, oxygen loss, and acidification will likely reduce the diversity of life in the sea, they will also impact fisheries, seafood farming, and recreational activities. These stressors will also interact and can have complex impacts. For example, as climate change progresses, hurricanes will become more frequent and intense. These hurricanes may redistribute nutrients that cause massive algal blooms that are sustained by warmer temperatures. When the blooms die off, microbes respire as they assist in the algae’s decomposition, simultaneously producing CO2 and consuming oxygen that cause ocean acidification and oxygen loss. The severe red tide along the Florida coast this year was likely a product of this series of events.

Read the full story at Forbes

Hawaii Prepares Plan to Help Coral Recover From Bleaching

September 9, 2016 — KANEOHE, Hawaii — Hawaii officials proposed a series of steps to fight coral bleaching that’s threatening the state’s reefs, including new marine protected areas, limits on fishing and controlling polluted runoff from land.

Hawaii’s ocean temperatures have been rising as greenhouse gases in the atmosphere have increased, forcing corals to expel algae they rely on for food. Vast stretches of reef have turned white over the past two summers, increasing the risk that the coral will get sick and die. Some already have died.

It’s a serious concern for the health of the ocean because coral reefs provide habitat for fish and other marine life, scientists say. Severe or concurrent years of bleaching can kill coral reefs, as has been documented over the past two years in oceans around the world. Scientists expect a third year of bleaching to last through the end of 2016.

Bruce Anderson, the state Division of Aquatic Resources administrator, said addressing polluted runoff is difficult, noting it would cost millions of dollars to create artificial wetlands that would help control runoff. Fishermen in the past have also resisted moves to limit their catch.

But Anderson said the coral bleaching crisis presents an opportunity.

“We are going to have future bleaching events, and the water is going to get warmer. And it’s going to happen again and again,” he said Thursday. “So our challenge is to prevent the impacts of bleaching as much as we can and also to help the reefs recover.”

Read the full story from the Associated Press at ABC News

International Study Finds Indian Ocean Warming Reducing Fish Catch

SEAFOODNEWS.COM [First Post] By Dinesh C Sharma — December 22, 2015 — Even as the world tries to make sense of decisions taken at the recent climate change conference in Paris, scientists have come up with fresh evidence of how global warming is beginning to nibble the food chain right in India’s neighbourhood – the Indian Ocean.

Oceans play a critical role in both short and long term weather and climatic patterns. Nearly 90 percent of extra heat generated due to emission of greenhouse gases from the landmass is absorbed by oceans, warming them up. Indian Ocean, considered one of the most productive seas, has seen warming greater than other oceans. The warming in Indian Ocean during the past century has been estimated up to 1.2 degree C, which is very large compared to a global surface warming of up to 0.8 degree C during the same period.

Now an international study led by scientists from Pune-based Indian Institute of Tropical Meteorology (IITM) has shown that the warming of Indian Ocean is affecting productivity of its marine eco system. Simply put, the food web necessary for fish production in the seas is getting affected due to the warming. This, in turn, is resulting in dwindling fish catch rates in the Indian Ocean.

The decline in phytoplankton- microscopic plants that are part of the aquatic food web – is significant. Phytoplankton contains chlorophyll and provides food for a range of sea creatures including fish. The rapid warming in the Indian Ocean has played an important role in reducing the phytoplankton up to 20 percent during the past six decades, the study has reported.

This story originally appeared on SeafoodNews.com, a subscription site. It has been reprinted with permission.