It’s a bit more swashbuckling than your average academic-paper photography.
CU Boulder’s Jessica Hankins and her colleagues don scuba gear and handle yard-long drills to extract core samples from 200-year-old coral, before hauling their calcified prizes back to a laser scope in Colorado.
On top of some documentary-worthy underwater photography at the Great Barrier Reef and the Hawaiian shallows, Hankins is bringing back news that the most important coral reefs in the world may be more resilient to climate change damage than previously thought.
The oceans absorb nearly a third of CO2 produced around the world from natural or human causes, and now they are getting full up from the massive increase in carbon dioxide output since the industrial age began. When saltwater absorbs carbon, it also turns more acidic, and the extra acid was thought to interfere with the way coral builds its complex molecular structure to grow into crucial, biologically diverse environments.
Headlines of massive coral bleaching and die-offs have become a regular part of climate anxiety around the world.
In “Raman microspectroscopy labs” in Hawaii and Boulder, named after the method’s inventor, Hankins and colleagues subjected the coral samples to laser analysis that measures the vibrations of molecules when hit by certain light wavelengths.
While ocean acidity has been rising steadily for 200 years, the corals Hankins studied — 115 and 200 years old from the Coral Sea near Australia — adjusted their own chemistry and continued to build the hard scaffolding of calcium carbonate.
“Corals are able to regulate, at least to some extent, the fluid that they’re forming their skeleton from, which is super-fascinating,” said Hankins, in an interview from Boulder Wednesday. “Despite the ocean becoming more acidic.”
Hankins is lead author of a paper on the coral discoveries published in “Science Advances,” and a Ph.D. candidate in geological sciences at CU.
“It’s an unexpected and hopeful signal,” Hankins said. “However, we need more long-term data to know what it really means.”
The last thing researchers want is various climate change debaters taking one study about one relatively small aspect of science and declaring “No worries from global warming!” Hankins is careful to describe the limitations of one method of analyzing one nature-made creation in the big picture of planetary climate.
“Warming, acidification, nutrient overload, storm data, there are so many things, but they rarely happen in isolation. The pressures from all of these stressors from climate change can overlap and interact in ways that are kind of hard to untangle,” Hankins said.
Bottom line, she added, is that the coral study is “this glimmer of evidence that’s super unique. Raman studies are not the full answer to all of these problems,” she said.
“But even saying that, yes, through Raman, I was able to show they were able to regulate their chemistry. It’s offering a valuable window into how corals are responding, both literally and figuratively,” Hankins said. “And I think it is giving us a really strong foundation to help us start unraveling the complexity of the stressors, and the coral responses.”