Ocean acidification in the freezer

Over a century after the Discovery Expedition (1901-04), our understanding of the environments and ecosystems in the Southern Ocean is still limited. Research efforts have focused on warming and ice melt as the environment changes. Now a new challange has emerged – ocean acidification – a concept that could not even have been comprehended 110 years ago as the ph was only defined in 1909.

Interannual variability of carbon fluxes in the North Sea from 1970 to 2006 – Competing effects of abiotic and biotic drivers on the gas-exchange of CO2

The three-dimensional biogeochemical model ECOHAM was applied to the Northwest European Continental Shelf (NECS) (47° 41′ – 63° 53′ N, 15° 5′ W – 13° 55′ E) for the years 1970–2006. The development of annual carbon fluxes was analysed for the North Sea as the inner shelf region. We divided the North Sea into several regions, the northern North Sea, the southern North Sea, the German Bight and the Southern Bight for a more detailed analysis. To separate the effect of physical and biological processes a second simulation without biology was performed. The results of our method for calculating the biological pCO₂ were in good agreement with the biological pCO₂ calculated after the method of Takahashi et al. (2002). While in the standard run the North Sea acted as sink for atmospheric CO₂, in the run without biology the North Sea was a continuous source for atmospheric CO₂.

The main drivers of the air-sea flux variability were identified as being temperature, net ecosystem production and pH. The eutrophication due to high riverine nutrient inputs during the 1980s had no significant effect on the air-sea flux of CO₂ because in contrast to net primary production, net ecosystem production did not respond to the period of higher phosphate input. The increase of sea surface temperature of 0.027 °C yr⁻¹ over the simulation period and the pH decline of 0.002 yr⁻¹ led to a decline of the uptake of atmospheric CO₂ by the North Sea of about 30% in the last decade of the simulation period. A special feature occurred in the year 1996, where a cold sea surface temperature anomaly led to an additional (physical) uptake of atmospheric CO₂ and corresponded with a low primary and net ecosystem production, which on the other hand led to less biologically induced uptake of CO₂.

Our results indicate an ongoing decline of the uptake capacity for atmospheric carbon dioxide of the North Sea for future scenarios.

State shellfish industry gets a shot in the arm

The state’s shellfish industry, besieged by pollution problems and neighbors who don’t want new and expanded geoduck farms, received a fresh show of support Friday from top state and federal officials.

Gov. Chris Gregoire, NOAA administrator Jane Lubchenco and others gathered at Taylor Shellfish Farms’ headquarters in a pep rally-like atmosphere to announce a new shellfish initiative to restore and expand the state’s shellfish resources.

The initiative calls for a streamlined, faster-paced permitting process for new and expanded shellfish farms, stepped-up restoration projects for two native shellfish populations – the Olympia oyster and pinto abalone – and new water-quality projects in shellfish-growing areas of Puget Sound.

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Details of the initiative include:

• The governor will appoint a blue-ribbon panel of scientists and others to create a plan for monitoring and combatting ocean acidification. Rising ocean acidity associated with greenhouse gases can lead to increased mortality in shellfish.
• The U.S. Environmental Protection Agency will direct $4.5 million to local governments and health districts to reduce bacterial contamination from failing septic systems, farm animals, pets and boats. Thurston and Pierce are among the five counties offered funding.
• Helping to recover Olympia oysters by restoring 19 natural oyster beds in Puget Sound by 2022.
• Increasing public access to shellfish on public tidelands for recreational and tribal harvest through new signs, maps and land acquisition.

AGU Fall Meeting: the (pH) lowdown on ocean acidification

Ocean acidification is often overlooked as a problem in favour of its more famous parent, climate change. But it’s receiving plenty of attention at the AGU Fall Meeting in San Francisco.

Whilst most information on the effects of acidification is based on modelling or lab experiments over limited time periods, Adina Paytan of the University of California Santa Cruz has been looking at whole ecosystems – the natural submarine springs, or “ojos”, that occur along Caribbean coastlines. Formed when rainwater travels through limestone caves under land and discharges into the sea via faultlines, these springs have a low pH, making them a natural laboratory for studying the effects of acidification on ocean-dwelling species over long timescales.

Ocean Acidification – Research notes from the School of Aquatic and Fishery Sciences

This website has been developed to serve as a portal for information on active research on ocean acidification within the School of Aquatic and Fishery Sciences at the University of Washington. Project highlights are provided below with occasional posts found in the adjacent column. In general most of our research focuses on how changing ocean conditions impact marine invertebrates.

Corals survive the acid test … rather, the acidic test

Caribbean species live, although not as diversely, in areas thought to be inhospitable

Certain species of corals have been discovered living in the surprisingly acidic waters of the Caribbean’s submarine springs, areas thought inhospitable to corals, a new survey has found.

However, these so-called single corals are not the reef-builders responsible for the large Caribbean reefs that form critical habitat for various species, while also performing other important roles in nature.

“While single corals may have the chance to survive … it would be very different from the coral reefs we know today and that we depend on today,” said Adina Paytan, a study researcher with the University of California, Santa Cruz, who presented her research here Wednesday at the annual meeting of the American Geophysical Union.

Paytan and her colleagues found three species of solitary corals growing in the relatively acidic waters flowing from natural springs along the coast of Mexico’s Yucatan Peninsula. Because of its chemical properties, this water was thought to be inhospitable to corals.

Ocean acidity is on the rise

Though the ocean covers nearly three-quarters of the Earth’s surface and provides a livelihood for at least 500-million people, little is known about how it is affected by climate change.

Participants at COP17 said that in coming decades the ocean and coastal regions would become increasingly stressed by at least three factors related to climate change. Impacts on fisheries, shells and corals had already been observed.

“Changes caused by climate change will affect the ocean in ways we are only beginning to understand. It is imperative that international decision-makers understand the enormous role the ocean plays in sustaining life on Earth and the consequences of a high-carbon world for the ocean and society,” said Carol Turley, knowledge co-ordinator of the ocean acidification research programme in the United Kingdom.

Impacts of increased atmospheric CO2 on ocean chemistry and ecosystems

Ocean pH is a function of the seawater carbonate system, which is a function of both the influx of CO2 from the atmosphere and the resulting concentration of CO2 in the water (i.e. pCO2). Uptake of anthropogenic carbon dioxide from the atmosphere is reducing ocean pH; a phenomenon referred to as ocean acidification. It is estimated that there has been a decrease of 0.1 pH units in the surface waters of the world’s oceans since the start of the industrial revolution with a reduction of 0.3 – 0.5 forecast by 2100. There is growing concern over the potential consequences of ocean acidification for marine ecosystems and the services they provide for mankind. This project was aimed at enabling the capability and developing the expertise within Ireland to measure and quantify the flux of CO2 into (or out of) the ocean; to monitor seasonal trends in pCO2 and CO2 fluxes; to determine the current baseline state and variability of the carbonate system; and to evaluate the potential impact of future changes on ecosystems with the ultimate aim of contributing to more informed policy development.