Published 8 October 2015
The conference on Ocean Acidification (OA), currently taking place in Auckland, is very relevant to the small atoll nation Tokelau.
Indeed the country is keen to become one of the pilot monitoring sites for the effects of ocean acidification. This is because the coral rims the three atolls are composed of, the lagoons they encircle, and the Pacific Ocean they are surrounded by, could all be affected by OA. Fishing is a key resource for survival on the islands, as well as for generating revenue. So monitoring the effect of ocean acidification is part of the survival strategy there.
All waters in our oceans are becoming more acidic, as a result of carbon dioxide emission from burning fossil fuels – as if causing climate change isn’t bad enough! Acidic oceans particularly affect shells and corals in coastal ecosystems – and fish in all the marine environments they live in. Very little is known on the exact degree of acidification and how it affects marine life. Hence the OA conference is setting priorities in finding out more of what’s happening in the Pacific Ocean.
Continue reading ‘Tokelau keen to monitor ocean acidification’
Published 8 October 2015
Tags: mitigation, Policy, review
Les océans sont menacés par le dérèglement climatique à plus d’un titre : réchauffement, acidification, montée des eaux… De grands dangers pèsent sur les espèces marines, mais aussi sur les services que rendent les océans à l’humanité.
Le 26 août 2015, la nasaa annoncé qu’une montée des océans d’au moins un mètre due au réchauffement climatique est inévitable dans les 100 à 200 prochaines années. La seule incertitude porte sur le rythme de ce phénomène. L’agence américaine alerte sur les dangers que courent les grandes villes situées en bord de mer telles Tokyo, Miami, Singapour… Cette hausse du niveau marin n’est qu’une des manifestations du réchauffement climatique. On doit aussi ajouter le réchauffement et l’acidification des eaux, les menaces sur les écosystèmes marins et côtiers… Malgré son immensité et son apparente stabilité, l’océan est touché de plein fouet par les modifications d’envergure que l’humanité inflige au climat de la Terre. (…)
Continue reading ‘Océans et climat : un duo inséparable (in French)’
Published 8 October 2015
- The United States announced that it is working to create a new and innovative public-private partnership involving several foundations that would provide resources to enhance the ability of African coastal States to monitor and better understand ocean acidification in the Indian Ocean. The United States intends to contribute resources to support the training of African scientists to monitor ocean acidification. Several foundations would provide contributions that will help African scientists acquire the oceanacidification monitoring technologies they need.
- New Zealand announced that it is funding a NZ$1.8 million (US$1.2 million) four-year project led by the Secretariat of the Pacific Regional Environment Programme, in partnership with the Secretariat of the Pacific Community and the University of the South Pacific, to help build the resilience of Pacific islands countries and territories to the impacts of ocean acidification.
Continue reading ‘Results of the 2015 “Our Ocean” Conference: preventing and monitoring ocean acidification’
Published 7 October 2015
NOAA has awarded more than $1.3 million to three universities for research on how economically and ecologically important marine species and coastal habitats are affected by ocean acidification.
The research that comes from these awards will tell scientists how the chemistry of the coastal ocean is changing, where these changes will be most acute, and what the effects of those changes will be on marine animals and habitats. It will also help coastal communities plan for these changing conditions.
Ocean acidification — the increase in seawater acidity caused by increased carbon dioxide in the atmosphere — has the potential to fundamentally change the ocean, its habitats, food webs and marine life. It can affect commercially important species such as crabs, oysters, clams and mussels directly, or by its effects on habitat-building species such as corals and sea grasses.
Continue reading ‘NOAA awards more than $1.3 million to predict coastal acidification impacts to commercial species and vulnerable habitats’
Recently, the effects of ocean acidification (OA) on marine animal behaviour have garnered considerable attention, as they can impact biological interactions and, in turn, ecosystem structure and functioning. We reviewed current published literature on OA and marine behaviour and synthesize current understanding of how a high CO2 ocean may impact animal behaviour, elucidate critical unknowns, and provide suggestions for future research. Although studies have focused equally on vertebrates and invertebrates, vertebrate studies have primarily focused on coral reef fishes, in contrast to the broader diversity of invertebrate taxa studied. A quantitative synthesis of the direction and magnitude of change in behaviours from current conditions under OA scenarios suggests primarily negative impacts that vary depending on species, ecosystem, and behaviour. The interactive effects of co-occurring environmental parameters with increasing CO2 elicit effects different from those observed under elevated CO2 alone. Although 12% of studies have incorporated multiple factors, only one study has examined the effects of carbonate system variability on the behaviour of a marine animal. Altered GABAA receptor functioning under elevated CO2 appears responsible for many behavioural responses; however, this mechanism is unlikely to be universal. We recommend a new focus on determining the effects of elevated CO2 on marine animal behaviour in the context of multiple environmental drivers and future carbonate system variability, and the mechanisms governing the association between acid-base regulation and GABAA receptor functioning. This knowledge could explain observed species-specificity in behavioural responses to OA and lend to a unifying theory of OA effects on marine animal behaviour.
Continue reading ‘Marine animal behaviour in a high CO2 ocean’
Marine dissolved organic matter (DOM) is one of the largest active organic carbon reservoirs on Earth, and changes in its pool size or composition could have a major impact on the global carbon cycle. Ocean acidification is a potential driver for these changes because it influences marine primary production and heterotrophic respiration. We simulated ocean acidification as expected for a “business-as-usual” emission scenario in the year 2100 in an unprecedented long-term mesocosm study. The large-scale experiments (50 m3 each) covered a full seasonal cycle of marine production in a Swedish Fjord. Five mesocosms were artificially enriched in CO2 to the partial pressure expected in the year 2100 (900 μatm), and five more served as controls (400 μatm). We applied ultrahigh-resolution mass spectrometry to monitor the succession of 7360 distinct DOM formulae over the course of the experiment. Plankton blooms had a clear effect on DOM concentration and molecular composition. This succession was reproducible across all 10 mesocosms, independent of CO2 treatment. In contrast to the temporal trend, there were no significant differences in DOM concentration and composition between present-day and year 2100 CO2 levels at any time point of the experiment. On the basis of our results, ocean acidification alone is unlikely to affect the seasonal accumulation of DOM in productive coastal environments.
Continue reading ‘Effects of ocean acidification on marine dissolved organic matter are not detectable over the succession of phytoplankton blooms’