A field study in the sea. (Photo Credit: NOAA/PMEL)
NOAA cruise to study acidification consequences on West Coast
Monday, July 29, 2013, 00:20 (GMT + 9)
A team of researchers from the National Oceanic and Atmospheric Administration (NOAA) will take and study samples of plankton, water and algae to better understand how acidification is affecting the oceans ecosystems.
The team, which includes biologists and chemists, will cover the US West Coast, sailing from Seattle (Washington) on 29 July and docking in San Diego (California) on 29 August on board NOAA ship Fairweather.
The US West Coast is particularly prone to acidification as the California Current, which runs from British Columbia to Baja California, causes deep waters rich in carbon dioxide (CO2) to interact with surface waters (also rich in CO2) so the marine ecosystems within it are affected.
Ocean acidification is the ongoing decrease in the pH of the Earth’s oceans. This change in the chemistry of the world’s seas is caused because the seas absorbe the excess CO2 from the atmosphere resulting from human interference, mainly as a result of burning fossil fuels and deforestation. The Earth’s carbon cycle is meant to be balanced but this destructive interference by humans have altered it adversely.
Since the Industrial Revolution (1760-1840), the oceans have absorbed as much as half of this excess CO2 and this has impacted negatively in the chemistry of surface seawater.
The excess CO2 dissolves in seawater forming carbonic acid (H2CO3) and lowering the waters pH level thus making it more acidic. This change in the sea oceans chemistry not only decreases the pH but also limits the quantity of carbonate ions available, which many creatures use to build shells and skeletons. Plankton, molluscs and coral are in dire straits to build or maintain their protective structures (calcium carbonate shells or skeletons). Since these are part of the oceans food chain, it also becomes affected.
Some of the invertebrates affected include oysters and mussels which are also victims of the corrosive effects of acidification. In the Pacific Northwest, the shellfish industry brings an estimated USD 111 m (of USD 270 m nationally) every year to the region’s economy, generating jobs for over 3,200 people, mainly in coastal communities.
Climate change and the greenhouse effect is one of the reasons why marine researchers are asking for urgent measures to be taken to stabilise and eventually reduce CO2 emissions.
By Gabriela Raffaele