Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sea Change: Researchers Use Computer Modeling to Understand Rising Seas and Coastal Risks

31.03.2011
Laid back beach communities, fragile wetlands perfect for canoeing or kayaking, and iconic lighthouses come to mind when picturing North Carolina’s coast.

In reality change is the norm along the coast, and although nothing is certain, a warming climate could mean quicker or more significant change over the next few centuries.

Scientists at RENCI and the University of North Carolina at Chapel Hill use the latest modeling techniques and high performance computing power to understand how expected increases in sea level over the next 100 years could affect coastal communities, wildlife and the coastline itself.

Most scientists believe that melt water from glaciers, the Greenland ice sheet and possibly the West Antarctic ice sheet, along with thermal expansion from warming oceans, will raise sea levels by one-half to 1 meter (1.6 to 3.2 feet) over the next century and by 1 meter to 2 meters (6.5 feet) over the next 200 years.

If that happens, North Carolina’s coast will change dramatically by 2100 or 2200, according to Tom Shay, a UNC-Chapel Hill marine scientist who conducts research with the UNC Institute for the Environment, the UNC department of marine sciences and UNC’s Center for the Study of Natural Hazards and Disasters.

“Some areas of the Outer Banks are only a few meters above sea level now, and there will be an increased tidal range and larger areas inundated by tides,” said Shay. With deeper water in the sounds, storm wave heights would increase as well, he said.

Some land areas, such as parts of the Albemarle and Pamlico peninsulas, will become submerged regardless of storms or high tides, said Shay. Coastal estuaries and the marine and plant life they support also might change due to the influx of higher salinity ocean water.

If sea level rises by a meter, “we will see higher tides, higher tidal velocities and tidal inundation every day,” said Shay. “And we’ll have a different shoreline.”

Shay uses the ADCIRC coastal storm surge modeling software and the SWAN (for Simulating WAves Nearshore) wave modeling software to create new “What If” models, showing how a major storm could affect the coast if sea levels were higher. The work complements work done at RENCI, which uses ADCIRC and SWAN to compute thousands of different possible storm scenarios. The Federal Emergency Management Agency (FEMA) uses the RENCI model output to develop new Flood Insurance Rate Maps (FIRMs) for coastal North Carolina as part of the North Carolina Floodplain Mapping Program.

Shay’s work zeroes in on one storm: Isabel, which made landfall in North Carolina in 2003 as a Category 2 hurricane. Using data on coastal topography and bathymetry compiled for the floodplain mapping modeling effort, Shay models the storm at current sea levels and at sea levels ranging from .5 to 2 meters higher.

Although his simulations show more pronounced storm surge and flooding during the hypothetical Hurricane Isabels, Shay stressed that the results depict a possible future, not a certainty.

“There are a lot of unknowns and uncertainties,” he said. “A warming ocean will cause some sea level rise just because of thermal expansion, but we don’t know how fast the ocean will warm or how fast the Greenland ice will melt or whether the West Antarctic ice sheet will melt. All those things have a range of possible outcomes and we want to understand as many of the possible outcomes as we can.”

Rising seas and changing risks
RENCI Senior Scientist Brian Blanton develops simulations using the same ADCIRC and SWAN models, but focuses on understanding the risks coastal communities will face from hurricanes and extratropical storms if sea levels rise.

“We are looking at the changes in risk associated with these storms—particularly risks from waves and surge—while making various assumptions about the future climate, such as increases in sea level, increasing rates of sea level rise and increased storm intensity,” said Blanton.

The work, funded by the North Carolina’s Floodplain Mapping Program, uses the same datasets as the floodplain modeling project and data from Applied Research Associates on probable hurricanes that could head toward North Carolina over the next 100 years. Blanton then uses that data to generate probable hurricane and severe storm events under different conditions that could be affected by climate change, such as higher sea levels, increased storm intensities and changes in the frequencies of storms.

The work will harness the power of a RENCI supercomputer to run about 2,000 individual storm simulations in six different climate scenarios, according to Blanton. Each simulation set will be crunched into statistical analyses that will help to clarify how coastal risks change under each climate scenario.

The end product, he said, will be a scientific evaluation of the risk of living on the coast—whether economic risk, risk to infrastructure or risk to lives—under changed conditions, which planners, emergency managers, scientists and policymakers will then be able to compare to their current understanding of coastal risks.

“With an understanding of not only the flood hazard data and the risk data but also of the uncertainty that goes along with that data—because the uncertainty can be quite high when your talking about a 100-year future climate—we hope to be able to inform the discussion on policy at the state, regional and maybe down at the county level as to what possible future risks may be,” said Blanton.

Karen Green | Newswise Science News
Further information:
http://www.renci.org

More articles from Earth Sciences:

nachricht Live from the ocean research vessel Atlantis
13.12.2018 | National Science Foundation

nachricht NSF-supported scientists present new research results on Earth's critical zone
13.12.2018 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>