Acidic oceans destroying sea life

Summary
11 March 2009


Mankind is changing the chemistry of the oceans and may be causing the decline of sea life. Experts say the ocean is more acidic now than it has been at any time in the past half-million years.

Reporter:
Roger Harrabin


CLICK PLAY BUTTON TO LISTEN




REPORT

Carbon dioxide is an acidic gas and scientists say as it dissolves into the sea it's making seawater more acidic. They calculate that ocean acidity is up 30% since the Industrial Revolution. A new study shows the growth of some tiny shell forming creatures appears already to have been stunted by the change.

Research of this new branch of science suggests that as CO2 emissions continue to increase, many shell forming species may not survive the next 50 - 100 years. This would hit commercial fisheries and start to unpick the very web of life in the seas.

Dr Carol Turley, who is running today's acidification debate in Copenhagen, fears a mass extinction: ''55 million years ago there was a big production of CO2. That resulted in the mass extinction of seabed dwelling shell forming organisms. What we’re doing now is far, far faster, so it may not be possible for organisms to adapt.''

Sceptics say we can't be sure how ocean chemistry will respond in the future and whether creatures will adapt. The scientists in Denmark say we simply shouldn’t take the risk.

Roger Harrabin, BBC News



CLICK PLAY BUTTON TO LISTEN TO WORDS REVIEW




VOCABULARY

> shell forming creatures
animals which make their own protective coverings often called 'shells'

> stunted
stopped from growing or developing to full potential

> species
group of animals or plants which have similar characteristics

> hit commercial fisheries
have a negative effect on the fishing industry

> to unpick the very web
to destroy the delicate balance

> acidification debate
discussion on the environmental issues caused by acid and pollution

> mass extinction
a large number of animals and sea life will no longer exist

> seabed dwelling
animals or creatures who live at the bottom of the ocean

> organisms
very small single living plants or animals (we often use this word when talking about extremely small forms of life e.g. amoebae and bacteria are single-celled organisms)

> sceptics
people who doubt, who don't believe


Source:
http://www.bbc.co.uk/worldservice/learningenglish/language/wordsinthenews/2009/03/090311_witn_ocean_page.shtml