By Michelle Werts

Green sea turtle
Green sea turtle. Credit: puuikibeach/Flickr

You know that old expression about “work following you home”? Well, last week, I had work following me on vacation. No, I wasn’t checking emails while visiting the Caribbean, but I did find myself reflecting on topics that are often discussed around the halls of American Forests and here on Loose Leaf, such as:

  • Rainforest deforestation – The island of St. Lucia used to be more than 80 percent rainforest, but those forests have been reduced to less than 45 percent due to past agricultural practices.
  • Endangered species – A snorkeling trip had me spying on threatened green sea turtles living in a protected bay and cove near St. Thomas, a U.S. territory.

And upon my return to work this morning, I found that the Caribbean had followed me home, as a study published yesterday in Nature Geoscience reveals how air pollution —something we normally discuss in the realm of how it affects human health, how it is impacting climate change, how forests help filter it — is affecting an unlikely species: coral in the Caribbean.

Reef off St. Croix, U.S. Virgin Islands
Reef off St. Croix, U.S. Virgin Islands. Credit: NOAA CCMA Biogeography Team

A team of climate scientists and coral ecologists studied coral growth rates in the western Caribbean between 1880 and 2000, using previously published data, and discovered that while coral may live under the sea, the atmosphere plays a big role in its growth.

In a release about the study, Dr. Paul Halloran explains that “particulate pollution or ‘aerosols’ reflect incoming sunlight and make clouds brighter. 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 study shows that in the early 1900s, slower coral growth rates were a result of volcanic activity, as aerosol emissions clouded the atmosphere, but by the late 1900s, aerosol emissions slowing coral growth could be attributed to industrialization.

Coral reefs support a fourth of the world’s oceanic species, and the researchers behind this new study hope it will lead to more understanding about how climate change and regional industrialization may affect coral habitats.