NOAA OCEAN ACIDIFICATION PROGRAM Ocean acidification is
occurring because the world’s oceans are absorbing increasing
amounts of atmospheric carbon dioxide, leading to lower pH and
greater acidity. This is literally causing a sea change and
threatening the fundamental chemical balance of ocean and
coastal waters from pole to pole. Ocean acidification refers to
a reduction in the pH of the ocean over an extended period,
typically decades or longer, which is caused primarily by uptake
of carbon dioxide from the atmosphere, but can also be caused by
other chemical additions or subtractions from the ocean.
Anthropogenic ocean acidification refers to the component of pH
reduction that is caused by human activity.(IPCC: Workshop on
Impacts of Ocean Acidification on Marine Biology and
Ecosystems). Over the last 250 years, the atmospheric
concentration of carbon dioxide has increased from 280 parts per
million to over 394 parts per million due to the burning of
fossil fuels (e.g., coal, gas, oil) and land use change