Coral reefs provide vital habitat for a whole myriad of oceanic life. While they are important to preserve for their own sake, coral reefs also benefit coastal structures and communities by providing protection from waves, floods, and storms. Possibly saving us $5.3 billion.
Trouble For Reefs
Coral reefs have been at risk for many years. Everything from plastic pollution to erosion is causing the death of coral. Coral bleaching, when the coral expels the algae living inside due to stress, is one of the biggest threats to a reef. If enough bleaching happens, the whole reef can collapse. Since bleaching happens when coral overheats, the fact that oceans absorb 93 percent of climate change heat has a devastating impact.
Researchers estimate that from the 1980s to 2010 the frequency of bleaching has increased from one event every 25 to 30 years to one event every six years. Since it takes a reef 10 to 15 years to recover from bleaching, we could see the complete destruction of the Earth’s reefs before they have a chance to recover.
In addition to the loss of the reef due to bleaching and coral death, researchers at the USGS found that the sea floor is eroding. The eroding sea floor has increased the water depth past levels originally predicted to occur in 2100. By 2100, we could see water depths two to eight times deeper than originally predicted. When combined with a sea level rise from a changing climate, coral reefs cannot keep pace.
Top Flood Protection
A study done by the University of California, Santa Cruz and the U.S.G.S uncovered what coastal communities would lose with the destruction of coral reefs. The study revealed shocking numbers. According to the study, “coral reefs offer more than $1.8 billion in annual flood protection to coastal communities. Losing 1 meter of reef height would cause 100-year flooding zones to increase by 23%, impacting 53,800 more people (a 62% increase) and 90% more property and increasing damages by $5.3 billion.”
The researchers created computer models that combined engineering, ecological, mapping, social, and economic tools to develop a dollar value for reefs. The models estimate that American reefs are worth over $1.6 million per mile – just for flood protection.
Their hope is by giving these reefs a value, they would be considered and managed as natural infrastructure. The results also identify where the protection from reefs is the best – helping coastal managers with planning everything from coastal defense to hurricane response and recovery.
Researchers from the ARC Centre of Excellence for Coral Reef Studies at The University of Queensland came to similar conclusions. They found that the three-dimensional structure of the reef significantly protects the coasts from waves, floods, and storms.
The team built experimental reefs on the Great Barrier Reef to study how the future climate scenario would play out. According to Associate professor Sophie Dove, “The combined impact of warming with the acidification of our oceans will see more than the collapse of ecosystems.” We can expect the loss of protection for coastal infrastructure and communities – starting by the end of the current century.