"The emerging pH data from sensors allows us to design lab experiments that have a present-day environmental context," said Hofmann. "The experiments will allow us to see how organisms are adapted now, and how they might respond to climate change in the future."
Hofmann researched the Antarctic, where she has worked extensively, as well as an area of coral reefs around the South Pacific island of Moorea, where UCSB has a Long-Term Ecological Research (LTER) project. She also studied the coastal waters of Santa Barbara, in conjunction with UCSB's Santa Barbara Coastal LTER. The research team provided 30 days of pH data from other ocean areas around the world.
The researchers found that, in some places such as Antarctica and the Line Islands of the South Pacific, the range of pH variance is much more limited than in areas of the California coast that are subject to large vertical movements of water, known as upwellings. In some of the study areas, the researchers found that the decrease in seawater pH being caused by greenhouse gas emissions is still within the bounds of natural pH fluctuation. Other areas already experience daily acidity levels that scientists had expected would only be reached at the end of this century.
"This study is important for identifying the complexity of the ocean acidification problem around the globe," said co-author Jennifer Smith, a marine biologist with Scripps. "Our data show such huge variability in seawater pH, both within and across marine ecosystems, making global predictions of the impacts of ocean acidification a big challenge."
Todd Martz, a marine chemistry researcher at Scripps, developed the sensor. "W
|Contact: Gail Gallessich|
University of California - Santa Barbara