Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Climate change reduces coral reefs’ ability to protect coasts

23.07.2015

Coral reefs, under pressure from climate change and direct human activity, may have a reduced ability to protect tropical islands against wave attack, erosion and salinization of drinking water resources, which help to sustain life on those islands. A new paper gives guidance to coastal managers to assess how climate change will affect a coral reef’s ability to mitigate coastal hazards.

About 30 million people are dependent on the protection by coral reefs as they live on low-lying coral islands and atolls. At present, some of these islands experience flooding due to wave events a few times per decade.


Aerial photograph of Kwajalein Atoll in the Marshall Islands showing its low-lying islands and coral reefs. A new study gives guidance to coastal managers to assess how climate change will affect a coral reef’s ability to mitigate coastal hazards.

Credit: Curt Storlazzi/USGS


Underwater image of a wave breaking over a coral reef on Kwajalein Atoll in the Republic of the Marshall Islands. This image shows how the high hydrodynamic roughness of live, healthy corals causes friction that induces breaking of waves over coral reefs, reducing wave energy at the shoreline that can cause flooding and island overwash.

Credit: Curt Storlazzi/USGS

It is expected that this rate of flooding will increase due to sea level rise and coral reef decay, as the remaining dead corals are generally smoother in structure, and do less to dissipate wave energy. Loss of coral cover not only causes increased shoreline erosion but also affects the sparse drinking water resources on these islands, which may eventually make these islands uninhabitable.

In order to prevent or mitigate these impacts, coastal managers need know to what extent their reef system may lose its protective function so that they can take action. The new study by researchers from the Dutch independent institute for applied research Deltares and the U.S. Geological Survey gives guidance on a local reef’s sensitivity to change. The new research has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union.

To gain insight into effects of changing conditions on coral reefs, the study authors used Xbeach, an open-source wave model. The computer model was first validated using field measurements obtained on the Kwajalein Atoll in the Marshall Islands in the Pacific Ocean, and was then used to investigate what the effects on water levels, waves, and wave-driven runup would be if certain reef properties change. Reef roughness, steepness, width and the total water level on the reef platform are all important factors for coastal managers to consider when planning mitigating measures, according to the study’s authors.

The results suggest that coasts fronted by relatively narrow reefs with steep faces and deeper, smoother reef flats are expected to experience the highest wave runup and thus the greatest potential for island flooding.

Wave runup increases for higher waves, higher water levels that are expected with sea level rise, and lower bed roughness that occurs as coral degrades and becomes smoother. These are all expected effects of climate change. Rising sea levels and climate change will have a significant negative impact on the ability of coral reefs to mitigate the effects of coastal hazards in the future, according to the new study.

The American Geophysical Union is dedicated to advancing the Earth and space sciences for the benefit of humanity through its scholarly publications, conferences, and outreach programs. AGU is a not-for-profit, professional, scientific organization representing more than 60,000 members in 139 countries. Join the conversation on Facebook, Twitter, YouTube, and our other social media channels.

Deltares is an independent institute for applied research in the field of water and subsurface. Visit http://www.deltares.nl

USGS provides science for a changing world. Visit USGS.gov

Notes for Journalists
A PDF copy of the article is available by clicking on this link: http://onlinelibrary.wiley.com/doi/10.1002/2015GL064861/abstract?campaign=wlytk-41855.5282060185

Or, you may order a copy of the final paper by emailing your request to Nanci Bompey at nbompey@agu.org. Please provide your name, the name of your publication, and your phone number.

Neither the papers nor this press release is under embargo.
Title
“The influence of coral reefs and climate change on wave-driven flooding of tropical coastlines”

Authors:
Ellen Quataert: Department of Applied Morphodynamics, Deltares, Delft, Netherlands; and Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands;

Curt Storlazzi: Pacific Coastal and Marine Science Center, U.S. Geological Survey, Santa Cruz, California, USA;

Arnold van Rooijen: Department of Applied Morphodynamics, Deltares, Delft, Netherlands;

Olivia Cheriton: Pacific Coastal and Marine Science Center, U.S. Geological Survey, Santa Cruz, California, USA;

Ap van Dongeren: Department of Applied Morphodynamics, Deltares, Delft, Netherlands.

Contact Information for the Authors:
Curt Storlazzi: +1 (831) 295-3429, cstorlazzi@usgs.gov

Ap van Dongeren: +31(0)88335 8351, ap.vandongeren@deltares.nl


AGU Contact:
Nanci Bompey
+1 (202) 777-7524
nbompey@agu.org

USGS Contact:
Leslie Gordon
+1 (650) 329-4006
lgordon@usgs.gov

Deltares Contact:
Mariska van Gelderen
+31 (0)6 13 67 13 70
Mariska.vanGelderen@deltares.nl

Nanci Bompey | American Geophysical Union
Further information:
http://news.agu.org/press-release/climate-change-reduces-coral-reefs-ability-to-protect-coasts/

More articles from Earth Sciences:

nachricht Supercomputing helps researchers understand Earth's interior
23.05.2017 | University of Illinois College of Liberal Arts & Sciences

nachricht How is climate change affecting fauna in the Arctic?
22.05.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

Im Focus: Bacteria harness the lotus effect to protect themselves

Biofilms: Researchers find the causes of water-repelling properties

Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Scientists propose synestia, a new type of planetary object

23.05.2017 | Physics and Astronomy

Zap! Graphene is bad news for bacteria

23.05.2017 | Life Sciences

Medical gamma-ray camera is now palm-sized

23.05.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>