Washington, July 4 : Chemical oceanographers have warned that human emissions of carbon dioxide have also begun to alter the chemistry of the ocean, which will likely require even steeper cuts in carbon emissions than those currently proposed to curb climate change.
Ken Caldeira of the Carnegie Institution’s Department of Global Ecology, writing with lead author Richard Zeebe of the University of Hawaii and two co-authors, note that the oceans have absorbed about 40% of the carbon dioxide (CO2) emitted by humans over the past two centuries.
This has slowed global warming, but at a serious cost: the extra carbon dioxide has caused the ocean’s average surface pH (a measure of water’s acidity) to shift by about
0.1 unit from pre-industrial levels.