Imagine a world without fish. The scenario seems inconceivable. But according to scientists such a catastrophe will in fact play out in coming generations unless we take bold actions to slow or stop Ocean Acidification.
Archive Page 27
Some experts fear that the Earth is more likely to be pushed past its tipping point by numerous small climate-change perturbations rather than a single massive upheaval.
Consider the plight of the lowly ocean periwinkle, a.k.a. Littorina littorea, once a staple of street stalls in cockney London. That delicious catchphrase “to winkle something out” derived from using a wire hook to extract this snail from its shell.
Continue reading ‘Ending with a wimper (sic)’
Some experts fear that the Earth is more likely to be pushed past its tipping point by numerous small climate-change perturbations rather than a single massive upheaval.
Consider the plight of the lowly ocean periwinkle, a.k.a. Littorina littorea, once a staple of street stalls in cockney London. That delicious catchphrase “to winkle something out” derived from using a wire hook to extract this snail from its shell.
Global warming destroying coral reefs too, says RP scientist
Published 27 October 2007 Science ClosedALAMINOS CITY, Philippines — The country’s coral beds may be under water but they are not immune to the effects of global warming, a scientist who pioneered the study of corals in the Philippines has warned.
Dr. Edgardo Gomez, the founding director of the University of the Philippines Marine Science Institute, said the country’s corals were already under threat from bleaching and illegal fishing, but ocean “acidification” caused by excessive carbon dioxide in the atmosphere (which also causes global warming) has become a more “serious concern.”
Continue reading ‘Global warming destroying coral reefs too, says RP scientist’
Response of eelgrass Zostera marina to CO2 enrichment: possible impacts of climate change and potential for remediation of coastal habitats
Published 26 October 2007 Science ClosedProjected increases in dissolved aqueous concentrations of carbon dioxide [CO2(aq)] may have significant impacts on photosynthesis of CO2-limited organisms such as seagrasses. Short-term CO2(aq) enrichment increases photosynthetic rates and reduces light requirements for growth and survival of individual eelgrass Zostera marina L. shoots growing in the laboratory under artificial light regimes for at least 45 d. This study examined the effects of long-term CO2(aq) enrichment on the performance of eelgrass growing under natural light-replete (33% surface irradiance) and light-limited (5% surface irradiance) conditions for a period of 1 yr.
Continue reading ‘Response of eelgrass Zostera marina to CO2 enrichment: possible impacts of climate change and potential for remediation of coastal habitats’
Copepod feeding and reproduction in relation to phytoplankton development during the PeECE III mesocosm experiment
Published 26 October 2007 Science ClosedWithin the frame of the Pelagic Ecosystem CO2 Enrichment (PeECE III) experiment, reproduction and feeding of the copepod Calanus finmarchicus was monitored in relation to phytoplankton development in two mesocosms, at present 1× (350 μatm) and ca 3× present (1050 μatm) CO2 concentrations, respectively.
Continue reading ‘Copepod feeding and reproduction in relation to phytoplankton development during the PeECE III mesocosm experiment’
Competition for inorganic and organic forms of nitrogen and phosphorous between phytoplankton and bacteria during an Emiliania huxleyi spring bloom (PeECE II)
Published 26 October 2007 Science ClosedLøvdal et al.
Using 15N and 33P, we measured the turnover of organic and inorganic nitrogen (N) and phosphorus (P) substrates, and the partitioning of N and P from these sources into two size fractions of marine osmotrophs during the course of a phytoplankton bloom in a nutrient manipulated mesocosm.
Continue reading ‘Competition for inorganic and organic forms of nitrogen and phosphorous between phytoplankton and bacteria during an Emiliania huxleyi spring bloom (PeECE II)’
Effects of increased seawater pCO2 on early development of the oyster Crassostrea gigas
Published 25 October 2007 Science ClosedKurihara et al.
This study demonstrated that the increased partial pressure of CO2 (pCO2) in seawater and the attendant acidification that are projected to occur by the year 2300 will severely impact the early development of the oyster Crassostrea gigas.
Dissolution of Carbonate Sediments Under Rising p CO2 and Ocean Acidification: Observations from Devil’s Hole, Bermuda
Published 24 October 2007 Science ClosedRising atmospheric pCO2 and ocean acidification originating from human activities could result in increased dissolution of metastable carbonate minerals in shallow-water marine sediments. In the present study, in situ dissolution of carbonate sedimentary particles in Devil’s Hole, Bermuda, was observed during summer when thermally driven density stratification restricted mixing between the bottom water and the surface mixed layer and microbial decomposition of organic matter in the subthermocline layer produced pCO2 levels similar to or higher than those levels anticipated by the end of the 21st century.
Tiny creatures near the base of the marine food chain lead perilous lives at best. Now they face a man-made threat. No, not global warming this time, though the root cause is the same. As the level of atmospheric carbon dioxide (CO2) rises, it is not only heating the globe but also dissolving in ocean waters, turning them more acidic. For shell-building animals that can mean a corrosive, even deadly environment.
Continue reading ‘Acid Threat’
Over 50 scientists of the ARC Centre of Excellence for Coral Reef Studies today declared the following statements unanimously:
Continue reading ‘Consensus declaration on coral reef futures’
Scientists will gather in Canberra on Thursday to discuss research showing the world’s oceans are becoming more acidic, creating a danger for vast numbers of marine creatures.
The coral scientists believe the increasing acidity is caused by the gradual buildup of carbon dioxide (CO2) in the atmosphere and dissolving into the oceans.
The Coral Reef Futures 07 Forum is being hosted by the Australian Research Council’s Centre of Excellence for Coral Reef Studies (CoECRS).
Continue reading ‘Scientists tackle acid buildup in oceans’
The world’s oceans may be losing their ability to soak up extra carbon dioxide (CO2) from the atmosphere, with the risk that this will help stoke global warming, two new studies say.
Absorption of atmospheric CO2 by the North Atlantic plunged by half between the mid-1990s and 2002-5, British researchers say in a paper published in the November issue of the Journal of Geophysical Research.
Continue reading ‘Oceans may be losing ability to absorb CO2’
«Surprise» chez les océanographes: les océans absorbent de mois en moins de dioxyde de carbone (CO2). Car il y aurait moins de CO2 dans l’atmosphère? Non, tout le contraire. Les rejets des activités humaines augmentent et l’océan a de plus en plus de mal à héberger sa part de gaz carbonique. C’est ce que révèlent une étude publiée par des chercheurs de l’université d’East Anglia (Grande-Bretagne) dans le journal de la recherche en géophysique. Ces données sont nouvelles puisque les scientifiques ne s’intéressent aux échanges de gaz entre les milieux marins et l’atmosphère que depuis 10 ans. Jean Pierre Gattuso est directeur de rechercher CNRS à l’Observatoire Océanologique de Villefranche-sur-Mer. L’océanographe s’inquiète pour les équilibres écologiques des fonds marins…
Continue reading ‘Le CO2 asphyxie les océans et les récifs coralliens’
WATERS around the Great Barrier Reef are becoming acidic at a higher-than-expected rate.
Ocean acidification, a side-effect of global warming, occurs when excess carbon dioxide dissolves into the ocean and becomes carbonic acid.
It is potentially devastating for the marine environment, affecting corals, crustaceans and plankton in particular.
Professor Malcolm McCulloch of the Australian National University said the findings were worrying.
Senate Passes Lautenberg Measure To Protect Oceans From Acidification
Published 21 October 2007 Media coverage ClosedBill Would Focus Research on Acidification, Which Threatens Marine Life and Fishing Industry; Sen. Boxer Co-Sponsors
(WASHINGTON, D.C.) – Legislation Sen. Frank R. Lautenberg (D–NJ) crafted to focus research on rising ocean acidity was added as an amendment to the Commerce, Justice, Science Appropriations bill that passed yesterday. Ocean acidification harms marine life, threatens the jobs of coastal workers and fishermen and poses serious risks to the fishing industry. The measure was co-sponsored by Sen. Barbara Boxer (D-CA).
Continue reading ‘Senate Passes Lautenberg Measure To Protect Oceans From Acidification’
A University of Queensland researcher says the earth’s corals could become extinct within decades because of increasing acid levels in the ocean.
Professor Ove Hoegh-Guldberg says carbon dioxide emissions must be reduced by 90 per cent by 2050 to protect coral reefs.
Continue reading ‘Emissions cut needed to save reef: researcher’
Ocean acidification disrupts induced defences in the intertidal gastropod Littorina littorea
Published 21 October 2007 Science ClosedBibby et al.
Carbon dioxide-induced ocean acidification is predicted to have major implications for marine life, but the research focus to date has been on direct effects. We demonstrate that acidified seawater can have indirect biological effects by disrupting the capability of organisms to express induced defences, hence, increasing their vulnerability to predation. The intertidal gastropod Littorina littorea produced thicker shells in the presence of predation (crab) cues but this response was disrupted at low seawater pH. This response was accompanied by a marked depression in metabolic rate (hypometabolism) under the joint stress of high predation risk and reduced pH. However, snails in this treatment apparently compensated for a lack of morphological defence, by increasing their avoidance behaviour, which, in turn, could affect their interactions with other organisms. Together, these findings suggest that biological effects from ocean acidification may be complex and extend beyond simple direct effects.
Concerns that sea life will struggle for survival as greenhouse gases make the oceans more acidic are amplified today by a study that shows that marine creatures such as snails and crabs will have weakened defences to protect them against predators.
Leaving aside the direct effects of greenhouse gases on climate change, the oceans “mop up” carbon dioxide from the atmosphere so that levels of carbonic acid rise. There are fears that the resulting rise in acidity could particularly affect sea creatures with hard shells because it cuts the availability of calcium carbonate (chalk) – which coral reefs, clams, molluscs and some plankton use to produce their hard skeletons.
The rising acidity of the seas is having a damaging effect on the hard shells of marine creatures like crabs
The acidity of the seas is having a damaging effect on the hard shells of marine creatures like crabs
Now it seems that the rise in the acidity of the seas has another effect on shellfish. Many marine creatures, from crabs and lobsters to molluscs, are able to protect themselves from predators by growing thicker shells when they are under greater threat.
The world’s oceans are becoming more acid, with potentially devastating consequences for corals and the marine organisms that build reefs and provide much of the Earth’s breathable oxygen.
The acidity is caused by the gradual buildup of carbon dioxide (CO2) in the atmosphere, dissolving into the oceans. Scientists fear it could be lethal for animals with chalky skeletons which make up more than a third of the planet’s marine life.
