Coral used to predict climate change effects (audio)

University of Queensland (UQ) researchers are planning to test whether the Great Barrier Reef will be able to recover from the effects of climate change.

The annual Great Barrier Reef coral mating season has begun and researchers on Heron Island off the Queensland coast are planning to capture coral sperm and eggs in order to subject them to different levels of carbon dioxide as they develop.

PhD student Alicia Lloyd from UQ’s Coral Reef Studies Centre says her team will collect coral eggs and sperm when the spawning begins to cross-fertilise with adult coral.

She says the aim is to grow coral in tanks with different levels of carbon dioxide and acidity.

Acidic seas threaten coral reefs

A volcanic crater that recently emerged in the Mediterranean Sea has made it possible to experiment on how corals will be affected as the oceans become more acidic from carbon dioxide.

An Italian group will present their preliminary findings in Wageningen, Netherlands at the “Reefs in a Changing Environment” symposium (13-17 December) organised by the International Society for Reef Studies.

Preliminary results show that corals exposed to lower pH levels suffer higher mortality than corals at current pH levels. Seawater worldwide is predicted to increase in acidity (decrease in pH) due to carbon dioxide emissions, which dissolve in water and cause acidity to rise.

New web site on benthic ocean acidification

What are the impacts of ocean acidification on key benthic (seabed) ecosystems, communities, habitats, species and their life cycles??

The average acidity (pH) of the world’s oceans has been stable for the last 25 million years. However, the oceans are now absorbing so much man made CO2 from the atmosphere that measurable changes in seawater pH and carbonate chemistry can be seen. It is predicted that this could affect the basic biological functions of many marine organisms. This in turn could have implications for the survival of populations and communities, as well as the maintenance of biodiversity and ecosystem function.

Special Issue – Seawater Acidification – will be published in Water

The following Special Issue will be published in Water (http://www.mdpi.com/journal/water/, ISSN 2073-4441), and is now open to receive submissions of full research papers and comprehensive review articles for peer-review and possible publication:

Special Issue: Seawater Acidification
Website: http://www.mdpi.com/si/water/seawater_acidification/
Guest Editors: Dr. Sam Dupont and Prof. Dr. Mike Thorndyke
Deadline for manuscript submissions: 31 May 2011

You may send your manuscript now or up until the deadline. Submitted papers should not have been published previously, nor be under consideration for publication elsewhere. We also encourage authors to send us their tentative title and short abstract by e-mail for approval to the editorial office at water@mdpi.com

This Special Issue will be fully open access, with Article Processing Charges (APC) waived for well prepared manuscripts submitted before 1 January 2011. The APC for manuscripts submitted after 31 December 2010 are 300 CHF. However, a fee of 250 CHF may apply if English editing or extensive revisions must be undertaken by the Editorial Office. More information can be found at http://www.mdpi.com/about/apc/.

Ocean acidification could affect fisheries

A free workshop on the topic of ocean acidification and its effect on seafood is scheduled for Tuesday, December 6th, 6p.m. to 8 p.m. in Portland, Maine at the Gulf of Maine Research Institute.

The Ocean Acidification Workshop for Gulf of Maine Seafood Producers is being hosted by Saint Joseph’s College of Maine and the Gulf of Maine Research Institute, in partnership with the Sustainable Fisheries Partnership.

The goal of the workshops is to inform commercial fishermen and other seafood producers about ocean acidification.

“Ocean acidification is not something that we can ignore,” SFP outreach coordinator Amy Grondin wrote in an e-mail. “We need to consider it now and engage seafood producers, researchers and policy makers in finding solutions. Globally, the seafood industry has been a minor contributor to the causes of ocean acidification – we burn fossil fuels to catch fish – but we will be the first to see the implications of the lowering pH of our oceans.”

EPA wants states to track ocean acidification

The Environmental Protection Agency has recommended that states begin identifying coastal waters impaired by ocean acidification. The idea is to find how pollution is affecting marine life.

When oceans absorb carbon dioxide from the atmosphere, they become more acidic.

The carbon comes mostly from humans burning things to create energy.

The EPA wants coastal states to start tracking how carbon dioxide may affect the ocean ecosystem.

Addressing ocean acidification on two coasts (video)

The Environmental Protection Agency’s memo on Ocean Acidification was part of settling a lawsuit that challenged the EPA’s failure to address the issue in the context of the Clean Water Act. To help us understand the topic from both coasts we spoke to Heather Goldstone of the Climatide blog that covers Cape Cod and Cassandra Profita of the Ecotrope blog based in Oregon.

Calcium carbonate saturation states in the waters of the Canadian Arctic Archipelago and the Labrador Sea

Ocean acidification is predicted to occur first in polar oceans. We investigated the saturation state of waters with respect to calcite (Ω_cal) and aragonite (Ω_arg) in six sections along an Arctic outflow pathway through the Canadian Arctic Archipelago (CAA) and into the northwestern Atlantic using dissolved inorganic carbon and total alkalinity measurements from 2003 to 2005. The study area, a key region connecting the Arctic and the North Atlantic, includes Smith Sound, Barrow Strait, Baffin Bay, Davis Strait, Hudson Strait, and the Labrador Sea. The average Ω_arg in the Arctic outflow was 1.18 ± 0.17 in Barrow Strait and 1.31 ± 0.14 in Smith Sound, with areas where Ω_arg < 1. The Arctic outflow through the CAA has a high content of Pacific waters, which have a low saturation state. These waters can be traced along the western Baffin Bay to Davis Strait. South of Davis Strait, this outflow is modified by mixing with slope and offshore waters of Atlantic origin and with the outflow from Hudson Strait. Despite the mixing, low saturation state water can still be identified on the southern Labrador Shelf. The aragonite saturation horizon is found at ∼150 m in Barrow Strait; at 200 m in Baffin Bay, Davis Strait, and Hudson Strait; and at 2300 m in the Labrador Sea. This study provides baseline data of the saturation states for the waters of the CAA and the northwest Atlantic. It also illustrates the downstream evolution of low saturation state Arctic outflow in the northwest Atlantic.

Seasonal and long-term changes in pH in the Dutch coastal zone (update)

Recent observations and modelling studies suggest that biogeochemical changes can mask atmospheric CO₂-induced pH decreases. Data collected by the Dutch monitoring authorities in different coastal systems (North Sea, Wadden Sea, Ems-Dollard, Eastern Scheldt and Scheldt estuary) since 1975 provide an excellent opportunity to test whether this is the case in the Dutch coastal zone. The time-series were analysed using Multi-Resolution Analysis (MRA) which resulted in the identification of system-dependent patterns on both seasonal and intra-annual time scales. The observed rates of pH change greatly exceed those expected from enhanced CO₂ uptake, thus suggesting that other biogeochemical processes, possibly related to changes in nutrient loading, can play a dominant role in ocean acidification.

Calcifying invertebrates succeed in a naturally CO2-rich coastal habitat but are threatened by high levels of future acidification (update)

CO₂ emissions are leading to an acidification of the oceans. Predicting marine community vulnerability towards acidification is difficult, as adaptation processes cannot be accounted for in most experimental studies. Naturally CO₂ enriched sites thus can serve as valuable proxies for future changes in community structure. Here we describe a natural analogue site in the Western Baltic Sea. Seawater pCO₂ in Kiel Fjord is elevated for large parts of the year due to upwelling of CO₂ rich waters. Peak pCO₂ values of >230 Pa (>2300 μatm) and pH_NBS values of <7.5 are encountered during summer and autumn, average pCO₂ values are ~70 Pa (~700 μatm). In contrast to previously described naturally CO₂ enriched sites that have suggested a progressive displacement of calcifying auto- and heterotrophic species, the macrobenthic community in Kiel Fjord is dominated by calcifying invertebrates. We show that blue mussels from Kiel Fjord can maintain control rates of somatic and shell growth at a pCO₂ of 142 Pa (1400 μatm, pH_NBS = 7.7). Juvenile mussel recruitment peaks during the summer months, when high water pCO₂ values of ~100 Pa (~1000 μatm) prevail. Our findings indicate that calcifying keystone species may be able to cope with surface ocean pH_NBS values projected for the end of this century when food supply is sufficient. However, owing to non-linear synergistic effects of future acidification and upwelling of corrosive water, peak seawater pCO₂ in Kiel Fjord and many other productive estuarine habitats could increase to values >400 Pa (>4000 μatm). These changes will most likely affect calcification and recruitment, and increase external shell dissolution.