Posts Tagged ‘coast’

UGA Skidaway Institute’s Alexander honored by coastal environmental group

January 5, 2017

University of Georgia Skidaway Institute of Oceanography Interim Executive Director Clark Alexander has been honored by the coastal environmental group One Hundred Miles as one of the group’s One Hundred Miles 100. The list is the first recognition of its kind to honor 100 individuals and organizations for their efforts to support the health, vitality and future of Georgia’s 100-mile coastline. Alexander was selected within the Researchers and Innovators category.

Alexander, a coastal geologist, was cited for his research efforts, which he began on the Georgia coast in 1989 when he first joined UGA Skidaway Institute. He was also cited by the environmental group for helping to advance the work of institutions across the coast. Alexander served on the Sapelo Island National Estuarine Research Reserve Advisory Board, the Gray’s Reef National Marine Sanctuary Advisory Council, and the Georgia Coastal Marshlands and Shore Protection Committees.clark-alexander-10-w

“Day in and day out, Clark advances our understanding of critical issues facing Georgia’s coast, including barrier island erosion patterns and the effects of climate change on marsh habitats,” his citation reads.

“Georgia’s coast is extremely fortunate to be under the stewardship of these exceptional leaders, conservationists and individuals who recognize its incomparable character and beauty and the essential role it plays in the well-being of our state,” said Catherine Ridley, vice president of education and communications at One Hundred Miles.

Alexander and the other honorees will be recognized with a reception immediately following the One Hundred Miles’ Coastal Conservation in Action: Choosing to Lead Conference on Saturday, Jan. 7, on Jekyll Island.

A full list of honorees is available at www.OneHundredMiles.org/OHM100.

Video — UGA Skidaway Institute scientists complete sea level study on Georgia coast

February 25, 2016

Sea level is projected to rise at least one meter by 2100. Where will that water go and how will it change the Georgia coastal ecosystem? University of Georgia Skidaway Institute of Oceanography scientist Clark Alexander and Georgia Southern University researcher Christine Hladik are attempting to answer those questions.

https://youtu.be/vNFrxb4cytU

Georgia Sea Grant makes awards to Skidaway Institute researchers

December 7, 2015

There was a nice article on the front page of this morning’s, Savannah Morning News. It highlighted three UGA Skidaway Institute research project that have received funding approval from Georgia Sea Grant.

You can read it here. 

Scientists use underwater robots to excite students about science

March 3, 2014

Can underwater robots catch the imagination of middle and high school students and spark an interest in science, technology, engineering and mathematics? Researchers and educators from the University of Georgia’s Skidaway Institute of Oceanography and Marine Extension (MAREX) think so. They are creating an education program focused on autonomous underwater vehicles (AUVs), also called gliders or underwater robots.

The program, “Choose Your Own Adventure,” will capitalize on Skidaway Institute’s expertise with AUVs and MAREX’s extensive history of marine education. Skidaway Institute scientist and UGA faculty member Catherine Edwards, and MAREX faculty members Mary Sweeney-Reeves and Mare Timmons will direct the one-year project.

Catherine Edwards (center) demonstrates an AUV to Mary Sweeney-Reeves (left) and Mare Timmons.

Catherine Edwards (center) demonstrates an AUV to Mary Sweeney-Reeves (left) and Mare Timmons.

The AUVs are a cutting-edge technology in marine research. The torpedo-shaped vehicles can be equipped with sensors and recorders to collect observations under all conditions. They are launched into the ocean and move through the water by adjusting their buoyancy and pitch. Because they are highly energy-efficient, gliders can remain on a mission for weeks at a time. Every four to six hours over their mission, they surface, report their data by satellite phone and receive instructions as needed.

Skidaway Institute’s AUV, nicknamed “Modena,” has been used in several recent projects, including “Gliderpalooza,” a simultaneous, cooperative launch of 13 AUVs from different institutions in 2013.

“Gliders are education-friendly, but the existing outreach activities are stale,” said Edwards. “Our program will develop the next generation of AUV outreach programs by combining cutting-edge, interdisciplinary research with educational activities and strong STEM components.”

The proposed work will highlight the problem of working with the strong tides that are characteristic of the Georgia coast. A big issue in operating gliders there is developing a guidance and navigation system that will function well in that kind of environment. The fast-moving Gulf Stream, located roughly 100 miles off the Georgia beaches, also introduces navigation problems.

“Although the AUVs have Global Positioning Systems and can be programmed to travel a set course, tidal and Gulf Stream currents can exceed the glider’s forward speed, which can take the instrument off course and keep us from collecting data where we need it,” Edwards said.

However, on the education side, the predictability of tides makes the proposed program highly intuitive and education-friendly.

“Students who grow up and live on the water already have an intuitive sense of tidal currents,” said Timmons. “Students understand why currents change during certain phases of the moon. This coastal intuition will provide a foundation for us to start an innovative, hands-on approach to STEM activities.”

Activities will depend on grade level so middle school students will have different objectives than those in high school. However, all the activities will address the direction and speed the AUV travels to a destination. The AUV direction and speed will depend on the sea state of coastal waters such as strong currents, storms or high winds.

To address the problem of strong tides, Edwards and a team of Georgia Tech graduate students, co-advised by Fumin Zhang, have developed the Glider Environmental Network Information System, called GENIoS, which optimizes a glider’s path based on data from real-time observations and ocean models. Current doctoral students Dongsik Chang and Sungjin Cho are working to upgrade the system to integrate real-time maps of surface currents measured by Skidaway Institute radar systems.

The education plan is to involve two local educators, April Meeks and Ben Wells, who teach in the Savannah-Chatham County Public School System. Since the activities are multidisciplinary, their expertise in building math curriculum will be valuable as the team integrates concepts of marine science, math and engineering into classroom activities.

“After the initial planning phase, we will be taking the program on the road to Chatham County schools,” said Sweeney-Reeves.

Activities will include student role-playing as an AUV maneuvers through a playing field of vector currents on a large game board. Successful arrival at their destination depends on how the individual pilot responds to currents, wind and density changes in route.

“The real fun will begin when obstacles, like underwater volcanoes, a giant squid or other surprises, cause the pilot to reroute the course of the AUV,” said Sweeney-Reeves.

The activities will allow students to develop analytical skills in a program that will be compliant with Next Generation Science Standards for the 21st Century in the common core state curriculum.

The funded study will include two short glider deployments. A summer 2014 deployment will be used for field-testing, software validation and developing real-world scenarios for the outreach program. A fall deployment will serve as an opportunity for classroom participants to communicate with the glider in real time.

“We hope this one-year program will serve as a springboard for future funding and continued joint outreach by Skidaway Institute and Marine Extension,” said Edwards. “We’d love to develop computer games and apps for tablets and mobile phones that let students fly gliders through even more realistic scenarios based on the measurements we collect in real time.”

The program is being funded through a joint grant from Skidaway Institute, UGA Public Service and Outreach, and the UGA President’s Venture Fund. The UGA President’s Venture Fund is intended to assist with significant funding challenges or opportunities. The fund also supports small programs and projects in amounts typically ranging from $500 to $5,000.

For additional information, contact Catherine Edwards at 912-598-2471 or catherine.edwards@skio.uga.edu; Mary Sweeney-Reeves at 912-598-2350 or msweeney@uga.edu; or Maryellen Timmons at 912-598-2353 or mare@uga.edu.

 

Skidaway Institute scientist presents coastal hazard program

April 29, 2013
Clark Alexander

Clark Alexander

The Skidaway Institute of Oceanography scientist Clark Alexander will present an informative and visual program on threats to the Georgia Coast in an “Evening @ Skidaway” reception and lecture on Tuesday, May 21, on the campus of Skidaway Institute.

The program will begin at 6:15 p.m. with a reception at the University of Georgia MAREX Aquarium to be followed by the science talk at 7:15 p.m. in the McGowan Library Auditorium.

The program is open to the public and admission is free.

Alexander’s talk is titled, “Coastal Crystal Ball: A Look at the Future of Georgia’s Changing Coastline.” Drawing on two decades of work in the area, Alexander will discuss coastal hazards relevant to Georgia, such as storms, beach erosion and sea level rise. He will introduce the Georgia Coastal Hazards Portal, a web-based tool that anyone can use to assess their specific exposure to coastal hazards, and present up-to-the-minute results of ongoing research to better quantify coastal Georgia’s hazard vulnerability.

The reception will include a demonstration of the Georgia Coastal Hazards Portal display located at the Aquarium.

Seating is limited. Please reserve seats by calling (912) 598-2325 or email to mike.sullivan@skio.usg.edu.

An “Evening @ Skidaway” is sponsored by the Skidaway Institute of Oceanography and the Skidaway Marine Science Foundation.

Skidaway Institute scientists seek answers to salt marsh questions

January 2, 2013

Salt marshes are a vital part of the coastal ecosystem. They provide a nursery for many kinds of marine animal life. Sitting in the transition zone between the ocean and the land, salt marshes serve as a physical buffer against severe weather. They act as a chemical buffer by capturing, holding and releasing nutrients that are brought in on each tide. As a result, the marshes have a great influence on the type and amount of nutrients that enter the sounds and the ocean. That buffering capacity varies on tidal, daily and seasonal time scales, but how it functions is poorly documented.

A team of Skidaway Institute of Oceanography scientists have begun a project to get a clearer picture of how salt marshes function and interact with their surrounding environment.

The composition of the science team reflects the interdisciplinary nature of the project. Principal investigator Jay Brandes, Aron Stubbins and Bill Savidge are chemical oceanographers, and Catherine Edwards is a physical oceanographer. Geologist Clark Alexander and physical oceanographers Jack Blanton and Dana Savidge are also contributing to the effort. The three-year project is funded by a $699, 971 grant from the National Science Foundation.

The research team at Groves Creek (l-r) Clark Alexander, Jack Blanton, Catherine Edwards, Jay Brandes, Dana Savidge, Bill Savidge, Aron Stubbins

The research team at Groves Creek (l-r) Clark Alexander, Jack Blanton, Catherine Edwards, Jay Brandes, Dana Savidge, Bill Savidge, Aron Stubbins

“Scientists have looked at salt marshes in the past and have gotten some good data,” Brandes said. “However, this will be the first detailed look at the combined functions of one of these marsh systems.”

The project will focus on Groves Creek, a portion of coastal salt marsh along the Wilmington River, adjacent to the Skidaway Institute campus. Groves Creek has been the site of other research projects.  Over the past three years, Blanton, Alexander, Dana Savidge and others have studied the topography and water-flow in the marsh as part of a Department of Energy-funded project.  Because of this, the physical layout of the marsh has been documented to a fine detail.

“We already know a lot about this area, especially how the water moves in and out of the marsh on the tides,” said Brandes. “We have a very good understanding of the topography of the top of the marsh and its tidal creeks, both above and below the surface.”

The scientists also believe the Groves Creek area is fairly representative of salt marshes along the Georgia and South Carolina coasts.

From a chemical standpoint, the research will focus on way the salt marsh uses carbon: is it a consumer or producer of carbon-based organic material and nutrients?

“Marshes take material in from the river on every high tide, and they deliver material back to the river on the falling tide — but it isn’t the same stuff,” Savidge said. “The marsh changes the river chemistry on every tidal cycle.”

There isn’t much consensus on what controls that exchange between river and marsh. “That is one of the big questions,” said Brandes, “Trying to understand whether the marsh is a producer or consumer, and how that changes over time, the seasons, the tides and so on.”

To get a detailed history of marsh-river exchange, the scientists will place sensors in the marsh that will measure various conditions every 15 minutes. Remote sensors cannot measure everything, so the research team will also be collecting samples on a daily basis and returning them to their labs for analysis.  Understanding the big picture will come from adding up all the little incremental changes over time and relating them to the actions of sun, tide and weather on the marsh surface.

Stubbins will focus his efforts on the role of dissolved organic carbon in the marsh. Savidge will work look at how the salt marsh uses dissolved oxygen. Edwards will be modeling how water flows in and out of the system and how that movement interacts with the chemical and biological activity.

When the project is complete in three years, the Skidaway scientists expect to have a much more extensive picture of the role salt marshes play in the larger coastal ecosystem.

nutri

Little help for marsh from eco-friendly dock designs

April 25, 2012

New dock designs intended to reduce damage to salt marshes are not much better than traditional docks, according to a recently completed study by Clark Alexander of Skidaway Institute of Oceanography. Alexander also concluded the compass orientation and height of a dock has more impact on the health of the salt marsh than the dock design or materials.

The problem is the shadow docks cast on the salt marsh vegetation beneath them. The marsh grass (Spartina alterniflora) does not flourish in reduced sunlight.  In recent years, alternative materials and designs have appeared on the dock-building market to try to mitigate this problem. Alexander tested three types of alternative material and designs – ThruFlow fiberglass-impregnated plastic grating; Gator Dock Fibergrate grating; and the DockRider Sundock, which uses a set of wooden rails and an electric trolley in place of traditional wood planking.

“These all sounded good,” said Alexander. “But what we didn’t know was if they actually worked effectively.”

To answer that question, Alexander conducted a three-year, two-part research project funded by a $195,488 grant from the Georgia Coastal Zone Management Program.

The first part of the study was to conduct field-based “before-and-after” studies of salt marshes where some of the new designs were being built. Alexander’s team collected samples and recorded conditions in the marsh before the docks were built and continued to monitor the salt marshes after they were completed.

In the second part of the study, Alexander and his team constructed four dock models, “mock docks”, using alternative materials on high ground at the Skidaway campus. The docks were placed in a field with unobstructed sunlight and were fitted with light meters that measured the amount of sunlight being received above and below each dock. The researchers measured the shadow footprint of the various dock designs over the course of two years.

Clark Alexander (r) and research team member Mike Robinson examine the light meter equipment beneath on of the mock docks.

“Because orientation is an important parameter in light transmission through these materials, we made the mock docks mobile, so we could re-oriented them during the four seasons to see the effects of orientation and seasonal sun angle” said Alexander.

They also adjusted the dock heights to assess the impact of height on light penetration to the ground below.

In the first part of the study, Alexander and his team examined three separate field sites – Turners Creek (ThruFlow decking), Shell Point Cove (Dockrider) and Betz Creek (traditional plank design) They measured the stem density of the marsh grass before the docks were constructed and then monitored it for two years after construction. Stem density in the dock shadow footprint decreased between 44 and 80 percent compared to nearby, non-dock sites.

The team also observed additional dock-related impacts. Some sections of salt marsh transitioned to denuded mudflats due to the marsh wrack that accumulated around the dock pilings.

The results of the field study were supported by the mock-dock project on the Skidaway campus. Seasonal measurements showed a significant reduction of the light needed to support the health of the marsh plants in the areas affected by the docks’ shadows.  At Skidaway Institute’s latitude, the elevation of the sun is high enough to allow sunlight to penetrate through the grated deck material only during the spring and summer, and even then, provides only about 10% more light than traditional plank decking.

The mock-dock project also documented two additional dock-shading impacts.  The compass orientation of a dock plays a significant role in the effect the dock has on the marsh. Docks that are oriented in a generally north-south direction have a much smaller shading impact than those oriented east-west. The height of the dock also has a significant effect. The duration of the shadow under the dock and the total light loss decreases as the height increases, up to 7 feet above the marsh surface, with smaller, less significant decreases above that height.

“The results of the two studies demonstrate that neither current alternative materials nor construction methods effectively negate the effects of dock shading in our region,” said Alexander. “However, the Dockrider system had one half to one third the shading impact of decked walkways in our study.”

“In addition to shading impacts, marsh wrack accumulation around dock and walkway pilings also negatively impacts the marsh and will be a problem with any piling-supported structure.”

The results of the study have been sent to the Department of Natural Resources, which will use these results to better manage the important coastal saltmarshes of Georgia.

Skidaway Institute researcher receives $377,000 grant to assess coastal vulnerability

February 3, 2012

Clark Alexander

Skidaway Institute of Oceanography scientist Clark Alexander has begun a multi-investigator project to assess the vulnerability of the Southeast Atlantic coast to future threats ranging from sea-level rise to shoreline erosion.

The project is funded by a $377,000 grant from the National Oceanographic and Atmospheric Administration. It is part of a larger, $1.06 million project awarded to the Governors’ South Atlantic Alliance (Alliance), to coordinate efforts in Georgia, Florida, South Carolina and North Carolina to develop a consistent method of assessing coastal threats in the four states.

“Our overall goal is to develop a process to evaluate our coast’s physical and economic vulnerability to hazards like sea level rise, flooding, storms, hurricanes and erosion, and do so in a uniform way throughout the region,” said Alexander.

A key component of the project is further development of a computer program called AMBUR. Originally created by Georgia Southern University’s Chester Jackson when he was a graduate student at Skidaway Institute, AMBUR is a powerful tool to evaluate erosion and accretion on a changing coastline.

“Dr. Jackson will enhance AMBUR’s capabilities so that it can be used to evaluate additional coastal characteristics,” Alexander said. “We want to include additional factors such as habitat, elevation, population density, economic valuation and different shoreline types.”

While Jackson is working on AMBUR, Alexander and his team will be collecting data on coastal physical, biological, demographic and economic parameters, while also meeting with coastal managers from the four states comprising the Alliance to determine which parts of the Southeast coast are most critically in need of assessment. Once identified, these areas will become the first coastal regions targeted for analysis with the new AMBUR tools.  When completed, the scientists will be able to present coastal managers with information and maps describing coastal vulnerability for at least a portion of each state. Future funding will be sought to expand the analysis to the whole southeastern coastal region.

“By its very nature, this project will identify the most vulnerable areas along the coast and will provide an unbiased analysis of the incentives and disincentives for development in those areas,” said Alexander.

The project is expected to run for 18 months.

Erosion threatens Coastal Georgia archaeological sites

August 1, 2011

Along the Savannah River in Chatham County are the remains of a large, complex, former rice plantation. Archaeologists may be able to learn much about the life of Georgia’s early inhabitants by studying this site, but only if they hurry. Site 9CH685, as it is known, is threatened by shoreline and tidal creek erosion – the result of the nearby river moving closer to the site every day.

Site 9CH685 is just one of 42 archaeological sites on Georgia’s back barrier islands recently studied by a team from the Skidaway Institute of Oceanography and the Georgia Department of Natural Resources (DNR) Historic Preservation Division. The sites include a range of types, from Native American shell middens to colonial cemeteries and Civil War artillery batteries. The team spent two years studying the erosion and accretion patterns near each site to assist DNR in prioritizing the sites that require the most immediate attention. Funding for the project came from the Georgia Coastal Zone Management Program.

“The Georgia coast is constantly evolving,” said Clark Alexander, the Skidaway Institute scientist who directed the project. “During the past 150 years, the shoreline has moved more than a hundred meters along many parts of the Georgia coast.  The natural forces of wind and water have formed and changed the shape of our coastline over the centuries and continue to do so.”

Typically it is not feasible to preserve sites against these forces, so it is critical to document the sites before they are lost if there is any hope to record the history contained within them.

“Once an archaeological site has been eroded away, it cannot be replaced and the information it contained is lost forever, said Chris McCabe,  deputy state archaeologist for the Georgia Department of Natural Resources (DNR). “The loss of archaeological information to natural processes in our dynamic coastal setting is an ongoing issue for us.”

The team used a combination of current shoreline measurements near the known sites, combined with historical shoreline information from aerial photographs, charts and maps, some dating back to the mid-19th century.

Skidaway Institute's Claudia Venhern uses a highly accurate GPS instrument to record the shoreline of a Georgia coastal island.

It was Skidaway Institute researcher Claudia Venherm’s job to survey the current shoreline. Using an extremely precise GPS receiver, she walked the shorelines measuring the exact location of the high water mark within a few inches. Later, she mapped the shoreline and compared it with the historic data for the same location to determine how fast the shoreline is changing.

“We can use Geographic Information System (GIS) technology to overlay the location of the current shoreline with the shorelines from older photos and maps and obtain a very good picture of what is happening to any piece of coast,” Venherm said.

All the sites were examined to determine which were in the most danger of loss to erosion. The projected life of each site was calculated as the number of years until erosion would destroy the entire site.

Six sites had already been lost to erosion by the time the team visited the coordinates for these sites. Four more sites were still present, but are completely or almost completely submerged at all stages of the tide. The team determined 21 of the sites were eroding, and three of those have a projected life of less than 50 years.

“This study will be a big help to us,” said McCabe. “We can’t stop the erosion, but we can prioritize our work, and maximize the amount of cultural information we obtain before a site is lost.”

That rice plantation site has already yielded clues about the early Georgia economy. The tidal creek threatening the main site has produced several surface artifacts from the late 19th and early 20th centuries. A section of whiteware dinner plate etched with the name “Greenwood China Company”, which designed dinnerware specifically for use aboard coastal steamboats, was found in the creek bed.

“This artifact suggests that materials from maritime vessels had found their way to a group of individuals living at the plantation,” said McCabe. “In addition, an aqua colored bottle embossed with the name ‘Packard & James New York’ was found.”

This merchant firm distributed spices and coffee at the end of the 19th century, and its discovery at a Savannah River site hints at important turn-of-the-century maritime sail and steam trading networks.

These glimpses into the past are fleeting however, as time and tide erase these ephemeral fragments of history.  This study provides the data that the DNR needs to save as much of Georgia’s rich coastal history as possible.

Skidaway Institute seeking ‘citizen scientists’ to assist with salt marsh study

February 11, 2011

Skidaway Institute of Oceanography professor Clark Alexander is looking for volunteer scientists to help him assess the problem of marsh wrack.

Marsh wrack is the dead marsh grass that forms large layers on top of the water or the marsh surface. Alexander is seeking volunteers willing to identify and photograph sites where wrack accumulates on at least a weekly basis throughout 2011.

Marsh wrack on Skidaway Island

As part of a grant funded by the Coastal Zone Management program, Alexander is working to assess the distribution and persistence of wrack in salt marshes throughout coastal Georgia. He and his team are using aerial photography to determine how much wrack is present in coastal Georgia and where wrack is found in different seasons.

“One additional issue that we want to address is how long wrack persists in a variety of marsh settings,” said Alexander. “To do that, we want to enlist the interested public to help us in documenting marsh wrack sites.”

The first step for any interested volunteers is to identify a site they are willing to photograph on at least a weekly basis.

“If you have a site you know accumulates wrack each year, but which has not accumulated any yet, you can monitor it for this project,” said Alexander. “Just start taking pictures right away so that we will have documentation of when it accumulates.”

Volunteers should have access to a digital camera and an email account, but no other specialized equipment is required.

Interested volunteers should send an email to Alexander at clark.alexander@skio.usg.edu.  He will provide a specific set of instructions.