Arctic ocean waters, ecosystem see increasing levels of acidity OSLO, Norway, May 6 (UPI) -- Carbon dioxide emissions are making arctic seas more acidic, something that would take tens of thousands of years to reverse, researchers say. Scientists from the Arctic Monitoring and Assessment Program, with headquarters in Oslo, Norway, said they have been recording widespread changes in ocean chemistry in the region that could bring major changes in the marine ecosystem. Carbon dioxide, a greenhouse gas responsible for global warming, also causes the world's alkaline seas to become more acidic as it is absorbed from the air, the researchers said, and the arctic is particularly susceptible because absorption is faster in cold water. "We have already passed critical thresholds," researcher Richard Bellerby from the Norwegian Institute for Water Research told BBC News. Even if we stop emissions now, acidification will last tens of thousands of years. Many creatures in the arctic ecosystem, including commercially valuable fish, could be affected by increasing levels of acidity, the researchers said. Scientists have estimated the average acidity of surface ocean waters around the globe has reached levels about 30 percent higher than before the beginning of the Industrial Revolution in the second half of the 18th century and the resultant increase in emissions of CO2, mostly from burning fossil fuels.