Coral reefs serve as natural barriers that protect adjacent shorelines from coastal hazards such as storms, waves and erosion. Projections indicate global degradation of coral reefs due to anthropogenic impacts and climate change will cause a transition to net erosion by mid-century. No studies have quantified the amount of regional-scale accretion or erosion that has occurred since the industrial revolution. Here, we calculate the spatial gains and losses of seafloor elevation and volume for 5 coral reef ecosystems in the Atlantic, Pacific and Caribbean over the last several decades. We show that these reef systems have already transitioned to a net-erosional state. Our most conservative estimates indicate mean seafloor elevation change at these 5 sites ranges from -0.06 to -0.8 m, corresponding to net volume losses ranging from 0.2 Mm3 to 52.8 Mm3 (million cubic meters). Regional-scale loss of seafloor elevation and volume has accelerated the rate of relative sea level rise, and increased current water depths of coral reef ecosystems to levels not expected until near the year 2100. The magnitude of erosion that has already occurred, trajectories for continued coral reef degradation and increasing sea level place these ecosystems and nearby communities at elevated and accelerating risk to coastal hazards. Our results set a new baseline for projecting future impacts to coastal communities resulting from erosion of coral reef systems and associated losses of natural and socio-economic resources.


Yates, K. K., US Geological Survey, USA, kyates@usgs.gov

Zawada, D. G., U.S. Geological Survey, USA, dzawada@usgs.gov


Oral presentation

Session #:18
Date: 06/22/2016
Time: 11:00
Location: 301 B

Presentation is given by student: No