Researchers from the University of Western Australia’s Oceans Institute have found that analyzing coral to determine past ocean temperatures can be misleading, the Australian Broadcasting Corporation has reported.
As coral grows, ratios of strontium to calcium imprint its calcium carbonate skeleton in a way that can illustrate previous years’ ocean temperatures.
However, when researchers analyzed core samples from two different coral colonies off Madagascar’s coast, one colony showed a strong warming trend while the other did not.
Researchers surmise that small differences in water temperature, salinity and waves and currents are responsible for creating microclimates that affect coral growth differently.
After reviewing the data, researchers concluded that testing large sample sizes may be the only effective way to measure ocean temperatures from coral.
Image: A coral reef in the U.S. Virgin Islands (Credit: NOAA)