A new report confirms earlier doomsday warnings from environmentalists. The oceans, which have absorbed excess carbon dioxide from the atmosphere for centuries, may be losing that ability.
Researches from University of East Anglia, in conclusion of a four-year study say that global warming is increasing wind speeds over the Southern Ocean and preventing it from absorbing more carbon. In addition, this is causing the sea to release some of the gas that it had stored before.
Says lead author lead author Corinne Le Quéré: "This is serious. All climate models predict that this kind of 'feedback' will continue and intensify during this century."
Oceans are believed to absorb about one-quarter to one- half of human-related carbon emissions linked to global warming. They are massive sinks that absorb such greenhouse gases.
While researchers say the oceans' removal of the carbon dioxide from Earth's atmosphere has slowed global warming, this resultant pile-up since the industrial revolution has had another drawback-adverse effects on marine life.
Scientists say that this sink effect is changing the ocean chemistry. The resulting changes have slowed growth of plankton, corals, and other invertebrates that serve as the most basic level of the ocean food chain. Scientists warn, the impacts on marine life could be severe.
"The oceans are performing a great service to humankind by removing this carbon dioxide from the atmosphere," says Christopher Sabine, a geophysicist with the National Oceanic and Atmospheric Administration in Seattle, Washington. "The problem is that this service has potential consequences for the biology and ecosystem structure of the oceans."
Since mass consumption of fossil fuels began with the industrial revolution around 1800, the concentration of carbon dioxide in the atmosphere has grown from an estimated 280 parts per million to around 380 parts per million.
Today's current level of atmospheric carbon dioxide is only around half of what scientists have predicted atmospheric levels should be, based on estimates that humans have contributed 244 billion metric tons of carbon dioxide to Earth's atmosphere.
Yet, one in a new generation of computer climate models that include the effects of Earth's carbon cycle indicates there are limits to the planet's ability to absorb increased emissions of carbon dioxide.
If current production of carbon from fossil fuels continues unabated, by the end of the century the land and oceans will be less able to take up carbon than they are today, leading to increased global warming, unpredictable climate changes and even threat to man's very existence on earth, warn scientists.