Ocean CO2 levels can influence climate

ZURICH, Switzerland, Oct. 24 (UPI) -- A Swiss-led study has found the concentration of carbon dioxide in the world's oceans has a significant influence on the Earth's global warming pattern.

Scientists at the Swiss Federal Institute of Technology note the planet's oceans contain about 60 times more CO2 than does the atmosphere. In the global carbon cycle, the sea absorbs a proportion of the atmospheric CO2, but also releases CO2 into the atmosphere. About half of the anthropogenic emission of CO2 is absorbed naturally by the oceans.

To discover how the situation has changed since the last ice age, researchers studied 20,000-year-old mud samples from the sub-Arctic Pacific Ocean lying approximately three feet below the present sea bed. They found the water in the ocean's depths exchanged less CO2 with the atmosphere than it does at present, while capturing more atmospheric CO2 than the water does today, suggesting as oceans become warmer as a result of climate change they release more carbon dioxide into the atmosphere.

The scientists say that finding has far-reaching consequences for Earth's climate.

The study appears in the journal Nature.