a news stream provided by the Ocean Acidification International Coordination Center (OA-ICC)
WASHINGTON, D.C. – Legislation by Sen. Frank R. Lautenberg (D–NJ) to focus research on rising ocean acidity passed the Senate Commerce, Science and Transportation Committee today. Ocean acidification harms marine life and poses serious risks to the fishing industry.
Continue reading ‘Senate Commerce Committee Passes Lautenberg Measure on Ocean Acidification’
Schulz et al.
Increasing atmospheric carbon dioxide (CO2) concentrations due to anthropogenic fossil fuel combustion currently change the ocean’s chemistry. Increasing oceanic [CO2] and subsequent decreasing seawater pH have the potential to significantly impact marine life. Here we describe and analyze the build-up and decline of a natural phytoplankton bloom initiated during the 2005 mesocosm Pelagic Ecosystem CO2 Enrichment study (PeECE III). We show that processes of inorganic carbon uptake in mixed surface waters and organic carbon export to depth were significantly enhanced at elevated CO2, while ammonium regeneration in deep waters was substantially reduced. This has important implications for our understanding of pelagic ecosystem functioning and future carbon cycling.
Continue reading ‘Build-up and decline of organic matter during PeECE III’
A CO2 enrichment experiment (PeECE III) was carried out in 9 mesocosms in which the seawater carbonate system was manipulated to achieve three different levels of pCO2. At the onset of the experimental period, nutrients were added to all mesocosms in order to initiate phytoplankton blooms. Primary production rates were measured by in-vitro incubations based on 14C-incorporation and oxygen production/consumption. Size fractionated particulate primary production was also determined by 14C incubation and is discussed in relation to phytoplankton composition. Primary production rates increased in response to nutrient addition and a net autotrophic phase with 14C-fixation rates up to 4 times higher than initial was observed midway through the 24 days experiment before net community production (NCP) returned to near-zero and 14C-fixation rates dropped below initial values. No clear heterotrophic phase was observed during the experiment. Based on the 14C-measurements we found higher cumulative primary production at higher pCO2 towards the end of the experiment. CO2 related differences were also found in size fractionated primary production. The most noticeable responses to CO2 treatments with respect to primary production rates occurred in the second half of the experiment when phytoplankton growth had become nutrient limited, and the phytoplankton community changed from diatom to flagellate dominance. This opens for two alternative hypotheses that the effects are either associated with mineral nutrient limited growth, and/or with a change in phytoplankton species composition. The lack of a clear net heterotrophic phase in the last part of the experiment supports the idea that a substantial part of production in the upper layer was not degraded locally, but either accumulated or exported vertically.
Continue reading ‘Primary production during nutrient-induced blooms at elevated CO2 concentrations’
PORT-OF-SPAIN, Trinidad: In collaboration with researchers at University of the West Indies (UWI) in Trinidad, Buccoo Reef Trust (BRT), and the Tobago House of Assembly (THA), the United States Geological Survey (USGS) has been working to investigate the effects of increased atmospheric carbon dioxide on the Buccoo Reef in Tobago.
This 5-year research project is expected to help determine the impact of ocean acidification on coral reefs. Buccoo Reef is the only site outside the United States where data will be collected.
Continue reading ‘US Geological Survey, UWI and THA collaborate on Tobago reef study’
Fossil fuel combustion and industrial processes release over six billion metric tons of carbon into the atmosphere each year. The consequences of these greenhouse gas emissions are often discussed in terms of rising global temperatures, but global warming is not the only threat from increased atmospheric concentrations of carbon dioxide (CO2). Ocean acidification, which occurs when CO2 in the atmosphere reacts with water to create carbonic acid, has already increased ocean acidity by 30 percent (Doney, 2006). Although the chemistry of this effect is well understood and not much debated, the full consequences of ocean acidification for marine ecosystems and human well-being are only beginning to be revealed.
Continue reading ‘Ocean Acidification, the Other Threat of Rising CO2 Emissions’
Acid oceans are the elephant in the room of global change – an event potentially so massive and profound in its implications for life on Earth that the world media has largely avoided it, governments shunned it and scientists discussed it mostly in muted tones, usually behind closed doors.
Riebesell et al.
The oceans have absorbed nearly half of the fossil-fuel carbon dioxide (CO2) emitted into the atmosphere since pre-industrial times, causing a measurable reduction in seawater pH and carbonate saturation. If CO2 emissions continue to rise at current rates, upper-ocean pH will decrease to levels lower than have existed for tens of millions of years and, critically, at a rate of change 100 times greater than at any time over this period. Recent studies have shown effects of ocean acidification on a variety of marine life forms, in particular calcifying organisms. Consequences at the community to ecosystem level, in contrast, are largely unknown. Here we show that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures of 350, 700 and 1,050 muatm increases with rising CO2.
Continue reading ‘Enhanced biological carbon consumption in a high CO2 ocean’
Microscopic ocean plants and animals may consume increasing amounts of carbon as oceans become more acidic, a new experiment carried out in the narrow fjords of Norway suggests. Scientists know that the world’s oceans are becoming more acidic from the absorption of carbon dioxide from power plants, factories, and vehicles. Experiments have already shown that acidity could eat away at the shells of marine organisms and interfere with the physiology of others. But Ulf Riebesell of the Leibniz Institute of Marine Sciences in Germany found that when he exposed waters to the carbon dioxide levels of today and of those projected for 2100 and 2150, plankton – the community of tiny ocean plants and animals – consumed more carbon without consuming more nutrients. However, it’s unclear whether this type of plankton consumption will be able to help lower carbon levels in the ocean, reducing climate change.
Continue reading ‘More acidic oceans could profoundly affect plankton’
A study published in the framework of the EU-funded CARBOOCEAN project in Nature reveals that ocean plankton will increase its consumption of dissolved inorganic carbon by up to 39% when CO2 concentration rises.
Continue reading ‘Plankton enables enhanced carbon consumption in the ocean, finds study’
Paulino et al.
We report the transient population dynamic response of the osmotrophic community initiated by a nutrient pulse in mesocosms exposed to different pCO2 levels as well as quantitative variations in phytoplankton and heterotrophic bacteria created by the difference in CO2 exposure.
The influence of seawater CO2 concentration on the size distribution of suspended particles (2–60 μm) and on phytoplankton abundance was investigated during a mesocosm experiment at the large scale facility (LFS) in Bergen, Norway, in the frame of the Pelagic Ecosystem CO2 Enrichment study (PeECE II). In nine outdoor enclosures the partial pressure of CO2 in seawater was modified by an aeration system to simulate past (~190 parts per million by volume (ppmV) CO2), present day (~370 ppmV CO2) and future (~700 ppmV CO2) CO2 conditions in triplicates.
Continue reading ‘Effects of CO2 on particle size distribution and phytoplankton abundance during a mesocosm bloom experiment (PeECE II)’
PARIS (AFP) — The ocean’s plankton can suck up far more airborne carbon dioxide (CO2) than previously realised, although the marine ecoystem may suffer damage if this happens, a new study into global warming says.
Continue reading ‘Global warming: Oceans could absorb far more CO2, says study’
Microscopically tiny marine organisms known as plankton increase their carbon uptake in response to increased concentrations of dissolved CO2 and thereby contribute to a dampening of the greenhouse effect on a global scale. An international group of scientists led by the Leibniz Institute of Marine Sciences in Kiel, Germany documented this biological mechanism in a natural plankton community for the first time. In simulations of the future ocean, they measured an increased CO2 uptake of up to 39%. The unexpected positive effect for the global climate system harbours at the same time considerable risks for the oceans and their ecosystems. The study points to three major areas of concern: increased CO2 uptake by plankton will accelerate the rate of ocean acidification in deeper layers, lead to a decrease in oxygen concentrations in the deeper ocean, and will negatively influence the nutritional quality of plankton. The latter development can have consequences for entire food webs in the ocean. The results of the study will appear in the international science journal “Nature” on November 11, 2007*.
Taking a page from Nature herself, a team of researchers developed a method to enhance removal of carbon dioxide from the atmosphere and place it in the Earth’s oceans for storage.
Unlike other proposed ocean sequestration processes, the new technology does not make the oceans more acid and may be beneficial to coral reefs. The process is a manipulation of the natural weathering of volcanic silicate rocks. Reporting in today’s (Nov. 7) issue of Environmental Science and Technology, the Harvard and Penn State team explained their method.
Continue reading ‘Scientists enhance Mother Nature’s carbon handling mechanism’
House et al.
We describe an approach to CO2 capture and storage from the atmosphere that involves enhancing the solubility of CO2 in the ocean by a process equivalent to the natural silicate weathering reaction. HCl is electrochemically removed from the ocean and neutralized through reaction with silicate rocks. The increase in ocean alkalinity resulting from the removal of HCl causes atmospheric CO2 to dissolve into the ocean where it will be stored primarily as HCO3− without further acidifying the ocean. On timescales of hundreds of years or longer, some of the additional alkalinity will likely lead to precipitation or enhanced preservation of CaCO3, resulting in the permanent storage of the associated carbon, and the return of an equal amount of carbon to the atmosphere. Whereas the natural silicate weathering process is effected primarily by carbonic acid, the engineered process accelerates the weathering kinetics to industrial rates by replacing this weak acid with HCl. In the thermodynamic limit—and with the appropriate silicate rocks—the overall reaction is spontaneous. A range of efficiency scenarios indicates that the process should require 100–400 kJ of work per mol of CO2 captured and stored for relevant timescales. The process can be powered from stranded energy sources too remote to be useful for the direct needs of population centers. It may also be useful on a regional scale for protection of coral reefs from further ocean acidification. Application of this technology may involve neutralizing the alkaline solution that is coproduced with HCl with CO2 from a point source or from the atmosphere prior to being returned to the ocean.
Climate change may get the most publicity, but it’s not the only global phenomenon linked to rising levels of carbon dioxide in the atmosphere. Another is the gradual acidification of the oceans, as more of CO2 dissolves in seawater, creating carbonic acid and lowering the pH.
Continue reading ‘More Acidic Seas Can Change Behavior of Anxious Sea Snails’
Prized as a luxury treat in the best restaurants and a staple food in the human diet for thousands of years, oysters and mussels are now being threatened by rising levels of carbon dioxide.
Mussels face extinction as oceans turn acidic
By 2100 some waters are expected to be corrosive enough to cause the shells of mussels to dissolve
By the end of the century many popular seafood dishes will disappear from our tables as shellfish become increasingly scarce, scientists warn.
Continue reading ‘Mussels face extinction as oceans turn acidic’
Rising acidity levels in the ocean, due mainly to increased levels of carbon dioxide from fossil fuels, could pose a major threat to New Jersey’s shellfish industry by the end of the century.
That view comes from scientists with the National Oceanic and Atmospheric Administration, or NOAA, and has drawn serious attention from U.S. Sen. Frank Lautenberg, D-N.J.
Lautenberg said the problem could harm the state’s $121 million-per-year shellfish industry. A NOAA scientist said the problem could affect 500 million people worldwide who rely on the ocean for food. In the U.S. alone, the fish and shellfish industry is worth $4 billion per year. Lautenberg has sponsored a bill to study the problem.
The immediate concern is that certain marine creatures, especially in their juvenile stages, may not be able to form calcium carbonate skeletons and shells if the ocean is too acidic. This includes plankton, shellfish, coral, sea urchins and starfish.
“Ocean acidification is a threat to our marine ecosystem and our economy. The change in ocean chemistry caused by greenhouse gases is corrosive and affects our marine life, food supply and overall ocean health,” Lautenberg said.
The Federal Ocean Acidification Research and Monitoring Act of 2007, or FOARAM, co-sponsored by Lautenberg and Sen. Barbara Boxer, D-Ca., would include $30 million to study the problem. The bill would lead to the formation of a committee and a national plan to address the issue.
Continue reading ‘Rising acid levels in oceans threaten shellfish’
When it comes to the oceans and carbon dioxide, there’s good news and bad news. To date, the world’s oceans have absorbed nearly a third of the excess carbon dioxide emitted as a result of anthropogenic activities. That may be good news for the atmosphere, but scientists and policymakers are increasingly concerned about the side effect of carbon dioxide absorption: ocean acidification.
