Sora Journal

Corals and Climate Change

By Sora Schools

In Megan Maeang’s Commotion in the Ocean High School STEM expedition, Caroline Rodriguez of the National Oceanic and Atmospheric Administration visited and shared her research on coral reef bleaching and climate change, as well as some background information on ocean acidification, which the class researched for their final project.

Caroline polled students on whether they had seen a coral and whether a coral is a plant or an animal (it’s an animal). She shared that coral is a colonial organism composed of thousands of animals called polyps. The polyps have mouths, stomachs, and tentacles. 

Students learned about the benefits of corals, symbiotic relationships, how they grow, and their benefits in the ecosystem.

“Corals are some of the most diverse and valuable ecosystems on earth,” said Caroline. 

Threats to Corals

Caroline also reviewed threats to coral reefs, such as overfishing, pollution, destructive fishing practices, collecting live corals, mining corals for building materials, disease, marine debris, and climate change.  

Caroline’s Research

Caroline explained the process of coral bleaching and thermal stress. When the water gets too warm, the corals expulse algae, leaving just the calcium carbonate skeleton. To assess the damage, you have to see how corals are changing over time. In the past, scientists would collect data via dives lasting 30 minutes to an hour. Caroline’s research involves something called photogrammetry, which is when a diver takes thousands of photos of the coral reef and then the team uses computer software to create 3D models of the reef and study it. 

Research was also conducted in the Galapagos Islands. Caroline and other researchers collected coral fragments and put them in a system called a coral bleaching assessment stress system (CBASS). They tested using different temperatures to see what was bleached. 

Ocean Acidification

Caroline shared that the concentration of carbon dioxide in the atmosphere began rapidly increasing in the 1950s. About a third of that gets dissolved into the ocean. This can lead to ocean acidification. 

Caroline shared about some groups working on researching and protecting corals as well as restoration efforts, such as growing corals and adding them to the reef. 

Students had the opportunity to ask Caroline more questions about her research and the work being done on coral reefs. Overall, this was a great opportunity for students taking the “Commotion in the Ocean” expedition to take a deep dive into the impact of ocean acidification on corals.