A new study reveals that air pollution can block coral from getting sunlight, a crucial factor in coral growth.
The study was conducted by coral ecologists and climate scientists from Australia, Panama and the United Kingdom. The type of particles that cause air pollution often derive from volcanic eruptions and burning coal.
"They are believed to be vulnerable to climate change and ocean acidification, but ours is the first study to show a clear link between coral growth and the concentration of particulate pollution in the atmosphere," Lester Kwiatkowski, a doctoral student of mathematics at the University of Exeter and lead author of the study said in a statement.
About one quarter of ocean species use coral for shelter and food and coral reefs are the most diverse of ocean ecosystems. The researchers came to their conclusion by studying records that included ship reports, data from the coral skeletons and climate model simulations. They found that the Caribbean's coral growth rates were impacted initially by early 20th century volcanic eruptions, then by human air pollution later in the 20th century.
While coral lives underwater, it requires photosynthetic algae as a source of nutrients and energy.
"Particulate pollution or 'aerosols' reflect incoming sunlight and make clouds brighter," Dr. Paul Halloran of the Met Office Hadley Centre said in a statement. "This can reduce the light available for coral photosynthesis, as well as the temperature of surrounding waters. Together these factors are shown to slow down coral growth."
The researchers hope that their findings will help determine future coral growth rates, based on air pollution sources and future carbon dioxide levels.
The news comes in the midst of other unsettling global warming news. Earlier this month, a study published in the journal Nature Climate Change revealed that the Arctic will turn into a lush, green landscape. The study was released around the same time that noxious algae blooms appeared in Lake Erie, turning the lake a nasty green. The blooms were likely exacerbated by global warming.
The results of the coral study are published in the journal Nature Geoscience.