Ocean acidification

Research suggests that higher-latitude reefs may have more time to adapt to rising ocean temperatures than their tropical counterparts

Researchers have long questioned what impact climate change has on the rate at which corals are growing and building reef habitats in the Florida Keys. A new study from the University of North Carolina at Chapel Hill explored this topic, finding both good and bad news. The rate of coral skeletal growth in the Florida Keys has remained relatively stable over time, but the skeletal density of the region’s corals is declining, possibly due to ocean acidification.

Continue reading ‘Florida Keys’ corals are growing but have become more porous’

Many of the world’s future farmers will likely be farming oceans, as aquaculture — the cultivation of fish and other aquatic species — continues its expansion as the fastest growing food sector. New research shows that in order for this next generation of farmers to thrive, there is an urgent need to prepare them for climate change.

Researchers from the National Center for Ecological Analysis and Synthesis (NCEAS) at UC Santa Barbara have published the first comprehensive analysis of how climate change could affect marine aquaculture production, specifically of finfish and bivalves (e.g., oysters), around the world. Published in the journal Nature Ecology and Evolution, their study, “Global change in marine aquaculture production potential under climate change,” reveals that climate change is not only a threat to global production in the future, but also is affecting producers today.

Continue reading ‘Marine aquaculture and the need to protect global food security’

Policymakers should heed the stories of fishermen who experience the effects carbon pollution has on their industry, as well as the science behind them.

Introduction and summary
In 2017, Maine’s seafood harvesters landed more than $569 million in seafood, sustaining the unique generations-old culture that distinguishes the Maine coast. Lobsters—worth more than $430 million—accounted for nearly 80 percent by value of that haul. Since 2004, the waters of the Gulf of Maine have warmed faster than nearly any other body of water on Earth, creating ideal temperatures for lobsters and leading to a population boom. Yet, amid the good fortune of this near-record haul—the fourth-highest in Maine history—the state’s lobstermen are far from jubilant as they watch ocean temperatures continue to climb and the lobsters continue their northward shift.

The worry for many is that the waters of the Gulf of Maine may become too warm to support lobsters. Dave Cousens, a former president of the Maine Lobstermen’s Association, told The New York Times, “Climate change really helped us for the last 20 years. Climate change is going to kill us, in probably the next 30.”

Continue reading ‘Warming seas, falling fortunes: stories of fishermen on the front lines of climate change’

PORTLAND, Ore.— The Center for Biological Diversity today filed a notice of intent to sue the Trump administration for refusing to recognize that ocean acidification caused by fossil fuel pollution is impairing waterways in Oregon.

Today’s filing notes that the U.S. Environmental Protection Agency has failed to fulfill its requirement under the Clean Water Act to identify waters impaired by ocean acidification so that they can then be subject to pollution controls and other mitigation measures.

Continue reading ‘Lawsuit launched over federal failure to address ocean acidification in Oregon’

New York State Department of Environmental Conservation (DEC) Commissioner Basil Seggos today announced the creation of a 14-member Ocean Acidification (OA) Task Force to assess impacts of acidification on the ecological, economic, and recreational health of New York’s coastal waters, work to identify contributing factors, and recommend actions to reduce and address negative impacts. The Task Force includes experts in climatology, hydrology, economics, marine fisheries, aquaculture, oceanography, and ecology. The task force’s first meeting will be scheduled this fall.

Commissioner Seggos said, “Governor Cuomo established New York’s Ocean Acidification Task Force to ensure that the best available science is used to assess and respond to this emerging threat to our coastal waters and fisheries. The task force is charged with providing New York with the tools and information to protect our natural resources from changing ocean chemistry and safeguard the long-term sustainability of our fisheries.”

Continue reading ‘DEC announces New York Ocean Acidification Task Force to evaluate impacts on state’s coastal waters’

The global ocean covers 70 percent of our planet, makes Earth habitable, and contributes to economies, food supplies, and our health. Yet the ocean is increasingly threatened by the growing amount of carbon dioxide in the atmosphere.

Two Lamont-Doherty Earth Observatory scientists affiliated with the Center for Climate and Life are leading research projects that examine a few of the ways climate change affects the health of the ocean. Both researchers use the fossil remains of sea creatures as natural recorders of past climate and marine ecosystem changes. The information they obtain from these provides clues about how the future ocean and its inhabitants might be shaped by climate change.

Their studies are funded in part by the Center’s partnership with the World Surf League PURE, which enables Lamont-Doherty scientists to pursue critical research that advances understanding of climate impacts on the ocean.

Ocean acidification: The other carbon dioxide problem

Bärbel Hönisch, a marine geochemist, studies how seawater chemistry changed through time. Today, the ocean is becoming more acidic due to the rising concentration of carbon dioxide in Earth’s atmosphere, about 30 percent of which is absorbed by the ocean. While this process helps to minimize global warming, the dissolution of carbon dioxide in the ocean leads to the formation of carbonic acid. As the name implies, the addition of carbonic acid makes seawater more acidic and this ‘ocean acidification’ makes it harder for calcifying organisms such as corals, mollusks, and some plankton to build their shells and skeletons.

The current pH of the ocean is around 8.1, representing a 25 percent increase in acidity over the past 200 years. As the amount of carbon dioxide in the atmosphere continues to rise, scientists expect seawater acidity to increase another 25 percent by the end of the 21st century. This level of acidification is similar to that of the Paleocene-Eocene Thermal Maximum (PETM), which occurred around 56 million years ago. During the PETM, a sudden rise in atmospheric carbon dioxide coincided with rapid warming and seawater acidification — conditions that lasted for 70,000 years or more.

Continue reading ‘Getting warmer: understanding threats to ocean health’

Did You Know?

• The current rate of change in ocean pH is roughly 50 times faster than known historical rates of change.
• Scientists estimate that the current rate of change in ocean pH has not likely occurred on the planet for the past 100 million years.
• More than one billion people worldwide get their primary protein food source from the ocean.

The amount of carbon dioxide (CO₂) emitted into the atmosphere has risen about 40% above pre-industrial levels. The oceans absorb about 25% of CO₂ released into the atmosphere, where the CO₂ reacts with seawater to form carbonic acid, which lowers ocean pH levels, making the water more acidic.

The acidity of ocean surface waters has increased by about 30% over the last 250 years and could become nearly 150% more acidic by the end of the century if CO₂ emission levels continue to increase at the current pace. Different regions of the ocean are more susceptible to an increase in acidification due to other factors such as coastal upwelling, river and glacial discharge, sea ice loss, and urbanization.

Continue reading ‘Marine life and ocean acidity’