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 Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland
15.11.2018 | Faculty of Science - University of Copenhagen

nachricht The unintended consequences of dams and reservoirs
14.11.2018 | Uppsala University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

Controlling organ growth with light

19.11.2018 | Life Sciences

New way to look at cell membranes could change the way we study disease

19.11.2018 | Life Sciences

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

VideoLinks
Science & Research
Overview of more VideoLinks >>>