May 14, 2014
Coral Reefs Reduce Risk Of Coastal Hazards, Climate Change
redOrbit Staff & Wire Reports - Your Universe Online
While an elevated risk of strong storms, flooding and other coastal hazards could be threatening the lives of hundreds of millions of people around the world, an international team of researchers writing in Tuesday’s edition of the journal Nature Communications has discovered an unusual way to reduce that risk: coral reefs.
“Coral reefs serve as an effective first line of defense to incoming waves, storms and rising seas,” study co-author Dr. Michael Beck, lead marine scientist of The Nature Conservancy and a research associate at the Institute for Marine Science, explained in a statement. “200 million people across more than 80 nations are at risk if coral reefs are not protected and restored.”
“This study illustrates that the restoration and conservation of coral reefs is an important and cost effective solution to reduce risks from coastal hazards and climate change,” added lead author Dr. Filippo Ferrario from the University of Bologna.
Dr. Beck, Dr. Ferrario and colleagues from the University of Bologna, The Nature Conservatory, the US Geological Survey (USGS), Stanford University and the University of California-Santa Cruz analyzed the global role and cost-effectiveness of coral reefs in reducing the risk of these coastal hazards.
They found that reefs provide “substantial protection” by reducing wave energy by an average of 97 percent across all tropical oceans. Eighty-six percent of that energy can be dissipated by the reef crest, or the shallowest part of the reef where the waves break first, they added.
The researchers report that at least 100 million people could receive risk reduction benefits from coral reefs, and point out that restoring them is far less expensive than other types of hazard mitigation strategies. While the median cost for building artificial breakwaters was calculated at $19,791 per meter, the per-meter cost of reef restoration projects was just $1,290.
The study also reported that there are 197 million people worldwide who could benefit from coral reefs alone, especially those in villages, towns and cities that live in low, risk prone coastal areas (below 33 feet in elevation) and within 30 miles of coral reefs. Most of those individuals resided in Indonesia (41 million), India (36 million), the Philippines (23 million), China (16 million) and Vietnam (9 million).
"Coral reefs are wonderful natural features that, when healthy, can provide comparable wave reduction benefits to many artificial coastal defenses and adapt to sea-level rise,” said co-author and USGS oceanographer Dr. Curt Storlazzi. “This research shows that coral reef restoration can be a cost-effective way to decrease the hazards coastal communities face due to the combination of storms and sea-level rise.”
“While there are many concerns about the future of corals reefs in the face of climate change, there are still many reasons for optimism about the future of coral reefs particularly if we manage other local stressors such as pollution and development,” added Dr. Fiorenza Micheli of Stanford University.