USGS Newsroom

New Tools to Help Manage Saltwater Intrusion

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 3 Apr 2013 15:21:18 EDT

Climate Change, Sea-Level Rise to Impact When Water is Available

COLUMBIA, S.C. – South Carolina and Georgia water resource managers have powerful new tools at their fingertips to help make critical decisions on the timing and quantity of freshwater availability in coastal rivers.

Developed by the U.S. Geological Survey and Advanced Data Mining International, the two new decision support systems will help decision makers determine how much drinking water they will be able to pull from rivers in the face of climate change, sea-level rise and saltwater intrusion.

The user-friendly products were developed as part a new report titled Simulation of salinity intrusion along the Georgia and South Carolina coasts using climate change scenarios.

Research shows that the availability of freshwater in coastal streams will likely be affected in the future due to the combination of climate change and sea-level rise. The balance between freshwater and saltwater in coastal streams is primarily governed by the interaction between streamflow and sea level, and coastal rivers are constantly responding to changing streamflow and tidal conditions.

The decision support systems -- which include salinity simulation models, model controls, historical databases, and model output in a spreadsheet application – were created for the cities and towns on the Georgia and South Carolina coast that withdraw drinking water from the Atlantic Intracoastal Water and the Waccamaw River in South Carolina, and the Savannah River in Georgia, to predict saltwater intrusion near municipal intakes.

"Predicting the changes in the frequency of salinity intrusion event is critical for water-resource planning in the coastal region of the Southeastern United States due to the large number of municipal water-supply intakes in coastal rivers," said Paul Conrads, a USGS hydrologist and lead author of the study.

At a location just downstream from an intake that provides drinking water for Myrtle Beach area, the decision support system estimated that a 1-foot rise in sea level would increase the frequency of salinity at the intake and double the amount of time that freshwater would not be available at the intake.

"The decision support systems for the two rivers are essentially easy-to-use spreadsheets that integrate all the science, data, and models needed to perform high quality risk assessments," said Edwin Roehl, lead software developer for the project.

The study also evaluated the effect of climate-change projections from a global circulation model on change in salinity intrusion. The global circulation models predict changes in precipitation and temperature. These changes can affect streamflows to the coasts and change salinity intrusion. The results from the global circulation model projections indicates that, for one intake, the annual number of salinity intrusion events will increase and there would be a seasonal shift, with most salinity intrusion events occurring in the fall rather than the summer.

Although increases in sea-level and reductions in streamflow show substantial effects that would have operational consequence for municipal water-treatment plants, the climate change scenarios shown in the report would allow water-resource managers to plan adaptation efforts to minimize the effect of increased salinity of source water. Adaptation efforts may include timing of withdrawals during outgoing tides, increased storage of raw water, timing larger releases of regulated flows appropriately to move the saltwater-freshwater interface downstream, and the blending of higher conductance surface water with lower conductance water from an alternative source such as groundwater.

Crowd-Sourcing the Nation: Using Volunteers for Enhanced Data Collection

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 1 Apr 2013 18:41:01 EDT

The USGS is expanding the involvement of volunteers to enhance data collection about structures for The National Map.

This program, known as The National Map Corps, focuses on encouraging citizens to collect data relating to structures by both adding new features and/or correcting existing data within The National Map database. These structures can include schools, hospitals, post offices, police stations and other important public places.

Collaborative pilot projects in Colorado were recently used to test the concept of crowd-sourcing. While the project is on-going, early indications point to positive results and show the success of using TNMC volunteers to enhance data sets.

Over a trial period of ten months, 143 volunteers collected, improved, or deleted data on more than 6,400 structures in Colorado. The volunteers’ actions were accurate and exceeded USGS quality standards. In the Colorado pilot project the volunteer-collected data showed an improvement of approximately 25 percent in both location and attribute accuracy for existing data points. Completeness, or the extent to which all appropriate features were identified and recorded, was nearly perfect.

The significant results of the Colorado pilot have led to a phased, nation-wide expansion of the crowd-sourcing /volunteer project. The states in the first expansion of TNMC are: Arkansas, Alaska, Colorado, Delaware, Georgia, Idaho, Maryland, Michigan, Montana, North Dakota, New Jersey, New Mexico, Ohio, Oregon, South Carolina, Utah, Washington, West Virginia

After an evaluation of the quality and procedures of the first group of states, the second set will be made available. Ultimately, by the end of 2013, the third batch of states will complete the expansion of the program.

"The response by volunteers in Colorado exceeded our expectations both in terms of the number of volunteers and the quality of the data they collected”, said Kari Craun, the Director of the USGS National Geospatial Technical Operations Center. “The Volunteered Geographic Information (VGI) community represents a fantastic, untapped resource to assist USGS in maintaining data that are part of The National Map.”

While some familiarity with the area that a volunteer chooses is helpful, one doesn’t have to live near a particular place to contribute. The tools on TNMC website, along with ancillary information available on the Internet, are generally sufficient to edit a distant area.

There have been several instances of crowd-sourced geographic information making significant contributions to research and databases in government, private sector, and non-profit organizations. The goal of the TNMC is to provide data for the nation’s primary federal mapping agency in its effort to provide accurate and authoritative spatial data via the web-based National Map.

The citizen geographers/cartographers who participate in this program will make a significant addition to the USGS’s ability to provide accurate information to the public. Data collected by volunteers become part of TNM Structures dataset which is available to users free of charge.

Without a network of volunteers, the desired information would not be collected this year and the existing data would not be updated. TNMC volunteers perform important work that otherwise will not be accomplished in the foreseeable future.

Becoming a volunteer for TNMC is easy; go to the National Map Corps website to learn more and to sign up as a volunteer. If you have access to the Internet and are willing to dedicate some time to editing map data, we hope you will consider participating!

Photos Reveal Severity of Hurricane Sandy's Coastal Impacts

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 9 Nov 2012 15:20:00 EDT

ST. PETERSBURG, Fla. – The USGS has released a series of aerial photographs showing before-and-after images of Hurricane Sandy’s impacts on the Atlantic Coast.

The photos, part of a USGS assessment of coastal change from as far south as the Outer Banks of North Carolina to as far north as Massachusetts, show that the storm caused dramatic changes to portions of shoreline extending hundreds of miles. Pre- and post-storm images of the New Jersey and New York shoreline in particular tell a story of a coastal landscape that was considerably altered by the historic storm.

"Sandy taught us yet again that not all Cat-1 hurricanes are created equal: the superstorm's enormous fetch over the Atlantic produced storm surge and wave erosion of historic proportions," said USGS Director Marcia McNutt. "We have seized this opportunity to gather unique data on a major coastline-altering event."

As major storms approach, the USGS conducts pre-storm and post-storm flights to gather aerial images along the length of the coastline expected to experience impacts from the storm’s landfall. Identifying sites of such impacts helps scientists understand which areas are likely to undergo the most severe impacts from future storms, and improves future coastal impact forecasting.

Photo pairs from North Carolina to Massachusetts will be made available online as the coastal change assessment continues.

"This storm's impact on sandy beaches included significant beach and dune erosion and minor disruption of infrastructure in the south," said USGS oceanographer Nathaniel Plant, "to extreme and often catastrophic erosion, overwash and sediment deposition, and inundation on northern beaches like Mantoloking, New Jersey."

Overwash occurs when storm surge and waves exceed the elevation of protective sand dunes, thereby transporting sand inland. In addition to threatening infrastructure like roadways, it can bury portions of buildings and cause extensive property damage. Since beaches and dunes serve as a first line of defense against extreme storms, this could further compromise the safety of coastal populations.

Data collected from these surveys are also used to improve predictive models of potential impacts from future severe storms. Before a storm makes landfall, USGS makes these predictions to help coastal communities identify areas particularly vulnerable to severe coastal change, such as beach and dune erosion, overwash, and inundation.

For instance, in the days before Sandy approached the eastern seaboard, the USGS ran models forecasting that 91 percent of the Delmarva coastline would experience beach and dune erosion, while 98 percent and 93 percent of beaches and dunes in New Jersey and New York, respectively, were likely to erode. Preliminary analysis suggests that Hurricane Sandy rapidly displaced massive quantities of sand in a capacity that visibly changed the landscape.

The USGS worked closely with the National Park Service to gather field data on pre- and post- storm conditions at Fire Island National Seashore on Long Island. The field team went to Fire Island in advance of the storm to capture the morphology of the beach and dunes. The team re-surveyed the beach to capture its state immediately after the storm, and they found drastic changes.

"We found that there was widespread dune erosion and overwash," said St. Petersburg-based USGS coastal geologist Cheryl Hapke. "On average the dunes eroded back 70 feet - the equivalent of 30-years of change, which had previously been measured. Our data also showed that dunes lost as much as 10 feet of elevation."

This rapid response data was used to help the National Park Service assess the areas of the coast that were most vulnerable to a nor'easter that impacted the coast a week after Sandy.

The USGS is also processing pre- and post-landfall airborne lidar data to gather information on the extent of coastal change caused by Sandy. Lidar, or light detection and ranging, is an aircraft-based remote sensing method that uses laser pulses to collect highly detailed ground elevation data.

USGS Releases Unconventional Gas Estimates for Five East Coast Basins

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 20 Jun 2012 11:04:29 EDT

Using a geology-based assessment method, the U.S. Geological Survey estimated a mean undiscovered natural gas resource of 3.9 trillion cubic feet and a mean undiscovered natural gas liquids resource of 135 million barrels in continuous accumulations within five East Coast Mesozoic basins, according to a new USGS report.

The area assessed extends across parts of Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, and Massachusetts. The five basins assessed are the Deep River, Taylorsville, South Newark, Dan River-Danville, and Richmond basins. Of those five, the Deep River, in North Carolina; the Taylorsville, primarily in Virginia and southern Maryland; and the South Newark, in New Jersey and Pennsylvania, are estimated to possess the most resource potential.

"Americans are currently benefitting from a plentiful supply of natural gas from continuous resource accumulations similar to the ones considered in this assessment," explained USGS Director Marcia McNutt. "By providing estimates of undiscovered resources, the USGS helps both producers and consumers understand the future for our domestic supply and the geographic locations for impacts from energy development."

The five basins formed 227 million years ago during the Mesozoic era along the continental margin in response to the regional uplift, extension (rifting), and crustal thinning that occurred during the early opening of the Atlantic Ocean. As the basins formed, they were filled with a variety of sediments, including boulder beds, coarse-grained fluvial to deltaic sandstones, red siltstones, mudstones, gray and black shales, and coal.

The USGS assessment of undiscovered gas resources ranges from 1.8 to 7.1 trillion cubic feet (95 percent and 5 percent probability, respectively). The assessment of undiscovered natural gas liquids ranges from 56 to 260 million barrels (95 percent and 5 percent probability, respectively).

Natural gas resources like those found in the East Coast Mesozoic Basins are known as continuous resources. Continuous resources have a close association with one or more petroleum source rocks and typically extend across a large area of accumulation. Continuous petroleum accumulations may be found in shale, coal, and sandstone. All of the accumulations assessed in this study are "tight gas sandstone" continuous reservoirs.

This assessment of the East Coast Mesozoic basins is based on the geologic and geochemical characteristics of the individual total petroleum systems, or TPS. For the petroleum source rock, the characteristics include the source rock richness, thermal maturation, timing of petroleum generation, and migration; for the reservoir rocks and seals, they include their stratigraphic position and content and petrophysical properties. Using this geologic framework, the USGS defined a composite TPS and an assessment unit for continuous accumulations in each of the 14 major East Coast Mesozoic rift basins. The basins are present both onshore and offshore, in State-administered waters, of the eastern United States. Of those 14 basins, only five had enough data to be quantitatively assessed.

The USGS acknowledges the directors and staff of the state geological surveys of North Carolina, Virginia, Pennsylvania, and New Jersey for providing geological information and assisting with the basin-analysis workshops, which were held in preparation for the USGS assessment.

USGS is the only provider of publicly available estimates of undiscovered technically recoverable oil and gas resources of onshore lands and offshore state waters. The USGS estimates of continuous accumulations within the East Coast Mesozoic basins are part of a nationwide project to assess domestic petroleum basins using standardized methodology and protocol.

To access this assessment, as well as learn more about USGS energy research, please visit the USGS Energy Resources Program, and stay up to date with USGS energy science by subscribing to the USGS Energy Newsletter or following us on Twitter.

A Big Day for Science: Citizens Have Contributed One Million Observations to Top Nature Database

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 3 May 2012 9:00:00 EDT

RESTON, Va. — Thanks to citizen-scientists around the country, the USA National Phenology Network hit a major milestone this week by reaching its one millionth nature observation.

The millionth observation was done by Lucille Tower, a citizen-scientist in Portland, Ore., who entered a record about seeing maple vines flowering. Her data, like all of the entries, came in through USA-NPN’s online observation program, Nature's Notebook, which engages more than 4,000 volunteers across the country to observe and record phenology – the timing of the recurring life events of plants and animals such as when cherry trees or lilacs blossom, when robins build their nests, when salmon swim upstream to spawn or when leaves turn colors in the fall.

Each record not only represents a single data point — the status of a specific life stage of an individual plant or animal on one day – but also benefits both science and society by helping researchers understand how plants and animals are responding to climate change and, in turn, how those responses are affecting people and ecological systems.

"My dream is that through the wonders of modern technology and the National Phenology Network we could turn the more than six billion people on the planet into components of our scientific observing system," said USGS Director Marcia McNutt. "We could make giant leaps in science education, improve the spatial and temporal coverage of the planet, lower the cost of scientific data collection, and all while making ordinary citizens feel a part of the scientific process."

Jake Weltzin, a U.S. Geological Survey scientist and the executive director of USA-NPN, concurs. "Hitting the one millionth observation is exciting because researchers and decision-makers need more information to understand and respond to our rapidly changing planet. More information means better-informed decisions that ensure the continued vitality of our natural areas that we all depend on and enjoy."

For example, said Weltzin, the data in Nature's Notebook are already being used to benefit society, including the development of more accurate indicators of spring, forecasting the onset of allergy seasons or the chances of western wildfires, managing wildlife and invasive plants, and setting goals for habitat restoration. Ultimately, such information can be used for better managing water resources, wildlife and ecosystem management, and even help farmers and ranchers across the nation.

Changes in phenology are among the most sensitive biological indicators of global change. Across the world, many springtime events are occurring earlier — and fall events happening later — than in the past. These changes are happening quickly for some species and more slowly, or not at all, for others, altering relationships and processes that have been dynamically stable for thousands of years. Some wildlife —like caribou and butterflies — are becoming mismatched from their plant food resources, which are responding differently. Migrations for some birds are changing too, as they can now overwinter instead of moving south for the winter, or as they fly north more quickly to keep pace with an advancing front of spring flowering.

Because of this, said Weltzin, scientists need more and better information about the pace and pattern of nature — locally to nationally — to answer important scientific and societal questions, and to build the tools and models needed to help people understand and adapt to the changes.

"So much of our improved understanding about global environmental changes is driven by varied and valuable sources of information that include networks of citizen-scientists," said John Wingfield, National Science Foundation’s assistant director for biological sciences. "The public at large has played an important role collecting observations and data for a hundred years and more. Knowledge and data gained from their work will continue to have a lasting effect on how we understand regularly recurring biological phenomena for hundreds of plant and animal species and contribute to the policy arena."

Gwen Lundburg in Seattle is one citizen-scientist who has contributed hundreds of entries into Nature’s Notebook. "Just noticing small changes like tiny purple lilac buds suddenly turning green has taught me to look more closely at my plants," Lundburg said. "I see things in my garden I never saw before."

With the help of citizen-scientist volunteers, working in concert with professionals, the USA-NPN, which was established in 2007, collects, stores and freely shares phenological data on more than 800 species of plants and animals. The Nature’s Notebook observing program has been in operation since 2009. The coordinating office of the organization is located at 1955 E. 6^th St., Tucson, Ariz., 85721. For more information, visit the USA National Phenology Network, or contact Jake Weltzin at 520-626-3821 or jweltzin@usgs.gov.

Rise in Asian Tiger Shrimp Sightings Prompts Scientific Look at Invasion Concerns

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 26 Apr 2012 11:00:00 EDT

Additional Contact: Keeley Belva, NOAA 301-713-3066 Keeley.Belva@noaa.gov

Content updated - 4/26/2012 6:48 pm

GAINESVILLE, Fla. – The recent rise in sightings of non-native Asian tiger shrimp off the U.S. Atlantic and Gulf of Mexico coasts has government scientists working to determine the cause of the increase and the possible consequences for native fish and seafood in those waters.

Researchers from the U.S. Geological Survey and National Oceanic and Atmospheric Administration are working with state agencies from North Carolina to Texas to look into how this transplanted species from Indo-Pacific, Asian and Australian waters reached U.S. waters, and what the increase in sightings means for native species.

"We can confirm there was nearly a tenfold jump in reports of Asian tiger shrimp in 2011," explained Pam Fuller, the USGS biologist who runs the agency's Nonindigenous Aquatic Species database. "And they are probably even more prevalent than reports suggest, because the more fisherman and other locals become accustomed to seeing them, the less likely they are to report them."

NOAA scientists are launching a research effort to understand more about the biology of these shrimp and how they may affect the ecology of native fisheries and coastal ecosystems. As with all non-native species, there are concerns over the potential for novel avenues of disease transmission and competition with native shrimp stocks, especially given the high growth rates and spawning rates compared with other species.

"The Asian tiger shrimp represents yet another potential marine invader capable of altering fragile marine ecosystems," said NOAA marine ecologist James Morris. "Our efforts will include assessments of the biology and ecology of this non-native species and attempts to predict impacts to economically and ecologically important species of the Atlantic and Gulf of Mexico."

The cause of the rapid increase in sightings remains uncertain, Fuller added. The non-native shrimp species may have escaped from aquaculture facilities, although there are no longer any known Asian tiger shrimp farms presently in operation in the United States. It may have been transported in ballast water from ships or possibly arrived on ocean currents from wild populations in the Caribbean or other locations.

Fuller's team at USGS has been tracking reports of Asian tiger shrimp since they first came to the attention of marine scientists and resource managers in 1988, when nearly 300 of them were collected off the coasts of South Carolina, Georgia and Florida within three months. Scientists tracked the cause back to an isolated incident that accidentally caused an estimated 2,000 animals to be released from an aquaculture facility operating at that time in South Carolina.

It was not until 18 years later that reports of the non-native shrimp resurfaced. In 2006, a commercial shrimp fisherman caught a single adult male in Mississippi Sound near Dauphin Island, Ala. Within months, additional specimens were noted in North Carolina’s Pamlico Sound, Louisiana’s Vermilion Bay and other parts of Florida and the Carolinas. The species was later reported off the coasts of Georgia, Mississippi and Texas in 2008, 2009 and 2011, respectively.

Scientists have not yet officially deemed the Asian tiger shrimp "established" in U.S. waters, and no one is certain what triggered the recent round of sightings. With so many alternative theories about where these shrimp are coming from and only a handful of juveniles reported, it is hard for scientists to conclude whether they are breeding or simply being carried in by currents.

To look for answers, USGS and NOAA scientists are examining shrimp collected from the Gulf and Atlantic coasts to look for subtle differences in their DNA, information that could offer valuable clues to their origins. This is the first look at the genetics of wild caught Asian tiger shrimp populations found in this part of the U.S., and may shed light on whether there are multiple sources.

"We're going to start by searching for subtle differences in the DNA of Asian tiger shrimp found here – outside their native range –to see if we can learn more about how they got here," said USGS geneticist Margaret Hunter, "If we find differences, the next step will be to fine-tune the analysis to determine whether they are breeding here, have multiple populations, or are carried in from outside areas."

Anyone who sees one or more shrimp suspected to be an Asian tiger shrimp is asked to note the location and report the sighting to the USGS NAS database. If possible, freeze a specimen to help confirm the identity and contribute to a tissue repository maintained by NOAA.

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USGS In the Surge Sampling for Nutrients, Sediment, E. coli, and Pesticides

OC_Web@usgs.gov (Office of Communications and Publishing) — Sun, 28 Aug 2011 14:39:09 EDT

Follow USGS on twitter @USGS to learn where the crews will be each day.
Media: If you would like to accompany a USGS crew during sampling, contact Kara Capelli at kcapelli@usgs.gov.

As Hurricane Irene has left her mark along the East Coast, USGS crews are sampling water for pesticides, E. coli, nutrients, and sediment to document water quality in areas affected by the hurricane. This sampling effort is part of the federal government’s broad efforts to ensure public health and to support the state, tribal, and local response to the storm.

Sampling is taking place along the East Coast. Crews will follow the path of the hurricane where it brought high flows.

“Significant high water events are important to document, because a storm event like this can flush large quantities of nutrients, pesticides, and bacteria into rivers and also alter sediment flow,” said Charles Crawford, coordinator of the sampling effort. “When looking at long-term water quality trends and year to year variation, this hurricane could be a defining event for 2011, and it’s important that USGS captures a complete picture of what happens this year.”

Excessive nutrients in the Nation’s rivers, streams and coastal areas are a major issue for water managers, because they cause algal blooms that increase costs to treat drinking water, limit recreational activities, and threaten valuable commercial and recreational fisheries. Increased sediment can cause costly changes in shipping channels, where new sediment can require additional dredging.

“The USGS creates models that relate nutrient, pesticide and sediment concentrations to how much water is flowing,” said Crawford.” In order to have the most accurate model, it’s important to document concentrations during a high flow event such as this one.”

Additionally, high flows from the hurricane have the potential to create higher concentrations of E. Coli in areas that use surface water for drinking.

USGS Responds to Hurricane Irene and Prepares for Aftermath

OC_Web@usgs.gov (Office of Communications and Publishing) — Sat, 27 Aug 2011 15:18:11 EDT

Storm-Surge Sensor Installations in Northeast Nearly Complete

* Reporters: want to join a crew recovering storm-surge sensors, making flood flow measurements, or sampling water quality? Contact the above points of contact.

Government scientists have blanketed the East Coast the past few days installing advanced equipment to monitor potential impacts from Hurricane Irene as it moves up the coast. This is part of the Federal government's broad efforts in support of state, tribal and local response to the storm.

U.S. Geological Survey crews completed installations of storm-surge sensors at key locations along the North Carolina coast, Chesapeake and Delaware Bays yesterday, and are finishing installations all the way up the east coast today.

In total, more than 260 emergency sensors needed to measure storm surge will have been installed in critical areas from North Carolina to Maine. The data that the sensors produce will help define the depth and duration of overland storm-surge, as well as the time of its arrival and retreat. That information will help public officials assess storm damage, discern between wind and flood damage, develop better land use and building codes, and improve computer models used to forecast future floods.

The USGS, in cooperation with state and federal agencies, already operates long-term sensor networks on inland rivers and streams throughout through out the nation. These networks provide real-time data important to the National Weather Service, FEMA and other USGS partners involved in issuing flood and evacuation warnings, coordinating emergency responses to communities, and operating flood-control reservoirs.

The information collected by the USGS real-time storm surge sensors is available online. Additionally, the USGS has deployed a live webcam at Virginia Beach, Va., to be able to observe the storm there.

Storm-surges are increases in ocean water levels generated at sea by extreme storms and can have devastating coastal impacts. The USGS studies the impacts of hurricanes and tropical storms to better understand potential impacts on coastal areas. Information provided through the sensor networks provides critical data for more accurate modeling and prediction capabilities and allows for improved structure designs and response for public safety.

In addition to the storm surge, the USGS is also looking at streamflows to assist in forecasting flooding, and how water quality and coastal geology may be impacted by the storm.

Streamgages and flooding

Hydrologists from USGS Water Science Centers up the entire coast are prepared to go into the field immediately after the worst of the storm passes to calibrate streamgages and ensure they transmit critical river level and flow velocity information to the National Weather Service for flood forecasting and to emergency officials for response.

Real time data from these streamgages is available online.

Precipitation in Maryland, New Jersey and New York during the last two weeks is already four to six times normal in some of these areas, according the NWS, with Hurricane Irene expected to add significantly to runoff. USGS crews will measure flood flows along streams and major rivers in the days following the storm.

Water quality

Other USGS crews will sample water quality at selected sites along the Atlantic coast to document the impact of Hurricane Irene on water quality. They will be monitoring concentrations and transport to coastal areas of nutrients, sediment, carbon, E. coli, and pesticides during the high flows expected along major rivers in the days following Irene.

Sand movement and overwash

USGS coastal geologists have forecast that sand may be washed inland, covering roads, evacuation routes, and lower levels of homes in the Outer Banks of North Carolina. USGS has completed pre-storm surveys to assess significant coastal erosion expected in this area, and is beginning post-storm survey flights as early as Sunday.

As USGS continues to take all appropriate preparedness and response actions as Hurricane Irene develops over the coming days, we encourage everyone to visit ready.gov or listo.gov for tips on creating emergency plans and putting together an emergency supply kit.

If you are in an impact zone, stay inside, away from windows, and off the roads. Irene remains a dangerous storm, and no hurricanes should be taken lightly.

If you are in an evacuation zone and can still leave, do so now-you are not just risking your own life, but putting first responders in danger and taking resources away from those who need help, including the sick and disabled.

USGS Installs Sensors along Atlantic prior to Hurricane Irene's Arrival

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 26 Aug 2011 12:51:23 EDT

Hurricane response crews from the USGS have installed storm-surge sensors at key locations along the North Carolina coast in advance of Hurricane Irene. And now, they are actively consulting with federal and state partners about the need for similar equipment for other coastal areas including the Chesapeake Bay, the Delaware Bay, Long Island Sound and even as far north as Cape Cod.

These storm surge sensors, housed in vented steel pipes a few inches wide and about a foot long, are being installed on bridges, piers, and other structures that have a good chance of surviving a storm surge during a hurricane. The information they collect will help define the depth and duration of a storm-surge, as well as the time of its arrival and retreat. That information will help public officials assess storm damage, discern between wind and flood damage, and improve computer models used to forecast future floods.

Storm-surges are increases in ocean water levels generated at sea by extreme storms and can have devastating coastal impacts. Current tracking shows Irene making first landfall over Carolinas’ Outer Banks and Virginia, with secondary landfall projected in New England.

In addition, rapid deployment gauges will be installed along critical roadways to provide real time information to forecast floods and coordinate flood-response activities in the affected areas. The sensors augment a network of existing U.S. Geological Survey gauging stations already in place before the storm arrives. The USGS crews installing the sensors come from water science centers from Georgia to Maine.

The USGS studies the impacts of hurricanes and tropical storms to better understand potential impacts on coastal areas. Information provided through the sensor networks provides critical data for more accurate modeling and prediction capabilities and allows for improved structure designs and response for public safety.

The USGS, in cooperation with state and federal agencies, also operates more permanent sensor networks installed along the East Coast of the U.S. These networks provide real-time data important to the National Weather Service, FEMA and other USGS partners involved in issuing flood and evacuation warnings and in coordinating emergency responses to communities.

Additional information can be found on the USGS Preparation and Data Collection Activity for Hurricane Irene, 2011 website.

As USGS continues to take all appropriate preparedness and response actions as Hurricane Irene develops over the coming days, we encourage everyone to visit www.ready.gov or www.listo.gov for tips on creating emergency plans and putting together an emergency supply kit .

Extent and Speed of Lionfish Spread Unprecedented

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 14 Mar 2011 8:30:00 EDT

Invasive Marine Fish May Stress Reefs

Gainesville, Fla. -- The rapid spread of lionfishes along the U.S. eastern seaboard, Gulf of Mexico, and Caribbean is the first documented case of a non-native marine fish establishing a self-sustaining population in the region, according to recent U.S. Geological Survey studies.

“Nothing like this has been seen before in these waters,” said Dr. Pam Schofield, a biologist with the USGS Southeast Ecological Science Center here. “We’ve observed sightings of numerous non-native species, but the extent and speed with which lionfish have spread has been unprecedented; lionfishes pretty much blanketed the Caribbean in three short years.”

More than 30 species of non-native marine fishes have been sighted off the coast of Florida alone, but until now none of these have demonstrated the ability to survive, reproduce, and spread successfully. Although lionfishes originally came from the Indo-West Pacific Ocean, there are now self-sustaining populations spreading along the western Atlantic coast of the U.S. and throughout the Caribbean.

It is not yet clear exactly how the new invasive species will affect reefs in this part of the world. Foremost on the minds of scientists is the lionfishes’ predatory behavior, which may negatively impact native species in the newly invaded ecosystems. They have already been observed preying on and competing with a wide range of native species.

Invasive lionfishes were first reported off Florida’s Atlantic coast in the mid-1980s, but did not become numerous in the region until 2000. Since then, the lionfish population has rapidly spread north through the Atlantic Ocean and south throughout most of the Caribbean. The spreading population is now working its way around the Gulf of Mexico.

Schofield spent years compiling and verifying sightings of lionfishes, reaching out to local experts such as biologists, museum curators, natural resource managers, divemasters and citizens groups to collect detailed records of specimen collections and sightings throughout the region. The records were compiled in the USGS Nonindigenous Aquatic Species database and used to map the fishes’ spread.

No one knows for sure exactly how the predecessors of the current population first made it into the Atlantic and Caribbean, but Schofield believes the invasion serves as a warning of the dangers posed by introductions of non-native fishes into an ecosystem.

“This invasion may constitute a harbinger of the emerging threat of non-native marine fishes to coastal systems,” Schofield said.

In the Florida Keys, Schofield and her team are working closely with partners from the National Oceanographic and Atmospheric Administration in Beaufort, North Carolina and Reef Environmental Education Foundation in Key Largo, Florida to analyze lionfish diets, an important first step in understanding their impact on reef ecosystems.

Eradication of lionfishes is probably not possible, admits Schofield. Yet, local control efforts may be able to keep the population tamped down, releasing pressure on the native ecosystem. Many Caribbean countries such as Bermuda and the Cayman Islands have begun lionfish control programs. In the U.S., REEF held a series of lionfish derbies in the Florida Keys that resulted in more than 600 lionfishes being removed from the Florida Keys National Marine Sanctuary.

Schofield’s most recent paper, “Update on geographic spread of invasive lionfishes in the Western North Atlantic Ocean, Caribbean Sea and Gulf of Mexico,” was published in the Dec. 2010 issue of Aquatic Invasions; it updates a 2009 article published in the same journal. For more information on lionfish, see the USGS Lionfish Factsheet.

Background on lionfish biology and ecology is also available on NOAA’s Lionfish Website. Information on REEF’s lionfish programs is available at their website.

[Access images for this release at: &amp;lt;a href="http://gallery.usgs.gov/tags/NR2011_03_14" _mce_href="http://gallery.usgs.gov/tags/NR2011_03_14"&amp;gt;http://gallery.usgs.gov/tags/NR2011_03_14&amp;lt;/a&amp;gt;]

Challenges identified in using models to predict snake and other animal invasions

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 9 Feb 2011 17:00:00 EDT

FORT COLLINS, Colo. — New research published today has identified challenges in using computer models to predict the potential of pythons or other invasive vertebrate species to spread across portions of the United States, according to the U.S. Geological Survey.

The study, published in PLoS One, assesses the accuracy and limitations of the MaxEnt modeling program for climate matching when applied to predicting the potential risk of vertebrate invasions in the U.S., especially pythons.

Climate matching for invasive species is the process of using climate data from a species’ native range to identify areas that are climatically similar outside of that range and which could be at potential risk for invasion.

A previous paper by USGS researchers Gordon Rodda, Catherine Jarnevich and Robert Reed published online in 2008 in the journal Biological Invasions used a rule-based model and had estimated climatic suitability for Burmese pythons to extend roughly over the southern third of the U.S.

After the Biological Invasions article was published, another group of scientists (Pyron et al.), from the City University of New York (PLoS One, 2008) used MaxEnt, a different climate-matching system, to re-assess the potential for invasion in the U.S. Their results contradicted the USGS 2008 conclusions by asserting that Burmese pythons posed a risk only to the area already occupied by this invasive species in southern Florida.

However, the new USGS research published today concluded that the Pyron et al. study incorrectly applied the MaxEnt modeling program and used some erroneous data. USGS researchers found that when Pyron et al. used MaxEnt's default (pre-set) settings, the model results predicted only very limited climate suitability for the species in Florida and in extreme south Texas. However, when USGS researchers (2011) ran the model again using more appropriate settings (such as limiting the number of parameters and limiting background data to the native range rather than global), it showed a greatly expanded area at risk, including much larger portions of the southern United States from California to South Carolina and many island territories.

USGS authors realized that Pyron et al. accidentally introduced errors such as using a dataset that included erroneous records for a different species of python. When the USGS authors removed these records and repeated the Pyron et al. analysis, different results were obtained, indicating the instability of the model when used in this manner.

Pyron et al. also used about 60 parameters in their models, although the most current guidance for doing these kinds of predictive models recommends that only about 10 parameters should have been used.

“When a model is excessively complex, it has a poor ability to accurately predict invasion risk,” said Gordon Rodda, the lead author of the study. “An excessive number of parameters means that each additional one acts as a filter, and using too many filters means that many sites that are truly at risk of python establishment get filtered out. In this case,” he added, “Pyron et al. incorrectly rejected many sites in the United States that may well have climate suitable for Burmese pythons.”

The new research also highlights the need for scientists to consider that factors other than climate – such as predators, disease or habitat -- may – and often do -- limit a species’ distribution. For example, said Rodda, when a potential invader is released in a new country, predators, diseases and other factors that limit the species’ population numbers in its homeland may not be present in the new place.

“This means the invader’s population may be able to expand into a larger area,” Rodda noted. “As a result, the areas at risk of invasion often extend to climate specifics not found in the native range boundaries. For example, the finding that heavy monsoons are present in the native range does not necessarily mean that a species requires monsoonal downpours to thrive.”

Adhering to the guidelines laid out in this paper and others for using MaxEnt produces more reasonable models. MaxEnt, when used appropriately, can produce useful models. The models for this paper were produced at the Resource for Advanced Modeling (RAM) at the USGS. Expertise at the RAM provides an environment for scientists and managers to carefully implement models such as MaxEnt and assess invasion risk.

The new study, Challenges in identifying sites climatically matched to the native ranges of animal invaders, is authored by Rodda, G.H., C.S. Jarnevich, and R.N. Reed. To see the article please go to PLoS ONE at http://dx.plos.org/10.1371/journal.pone.0014670.

Groundwater Resources Generally Abundant in Coastal Carolinas

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 16 Nov 2010 10:51:03 EDT

The report, “Groundwater Availability of the Atlantic Coastal Plain of North and South Carolina,” is available online.

Large volumes of high quality groundwater fill aquifers along the Atlantic Coastal Plain (ACP) in North and South Carolina. Groundwater levels in much of the region remain relatively unchanged from predevelopment days, despite declines in some locations from large-scale pumping.

These are among the key findings of a major federal study, conducted by the U.S. Geological Survey, to assess the status of the region’s groundwater resources, examine how they have changed over time, and develop tools to assess the sustainability of these resources in the Atlantic Coastal Plain of the Carolinas.

“Groundwater availability in the ACP is good, in that supply generally exceeds demand,” said Kevin Dennehy, coordinator of the USGS Groundwater Resources Program. “However, groundwater is not abundant everywhere.” Examples of less abundant resources occur in the Tertiary aquifer near Savannah, Georgia and Charleston, South Carolina.

Groundwater levels have also been declining in the North Carolina Central Coastal Plain Capacity Use Area, a 15-county area in the central part of the North Carolina Coastal Plain, since the 1960s. These declining water levels are the result of large-scale pumping combined with sluggish groundwater flow.

However, in Sumter and Aiken, South Carolina, no major groundwater level declines have occurred, despite relatively large volumes of groundwater pumping for public supply needs. Detailed groundwater budgets for these areas and the regional Coastal Plain aquifer system are but one of the products produced from this in-depth assessment.

“Groundwater levels near the Fall Line rise faster following precipitation and drop faster during drought than they do along the coast,” said Bruce Campbell, USGS hydrologist and lead scientist on the North and South Carolina ACP study. The Fall line is the boundary between Coastal Plain sediments and the Piedmont Plateau. “These fluctuations, coupled with increasing demand, make water management a serious challenge for most places within the study area,” said Campbell.

“Rapid growth in coastal populations combined with the 1998-2002 drought in the Eastern United States, led to declining groundwater levels and initiated interstate cooperation in assessing groundwater supplies,” said Dennehy. “This study is intended to aid state and local water officials to better manage their groundwater supplies.”

A groundwater flow modeling tool was developed and used to simulate future groundwater level responses to increased development. The modeling tool also simulates groundwater level changes based on varying precipitation rates related to potential scenarios of climate change from 2010 to 2100.

Simulating future scenarios allows water managers to make informed decisions in anticipation of increased development of water supplies in response to continued and sometimes rapid growth in population within the Atlantic Coastal Plain of the Carolinas.

Predicted effects of future climate changes include substantial fluctuations in groundwater levels. However, the effects of forecasted precipitation on groundwater levels differ in the Inner and Outer Coastal Plains.

The Inner Coastal Plain is more susceptible to changes in precipitation because this area typically experiences high rainfall and direct recharge of the aquifers. The Outer Coastal Plain is less susceptible and, consequently, groundwater availability may be less affected.

The study conducted on the ACP is one of more than 30 regional priority aquifer studies being conducted by the USGS across the country. When all of the studies are completed, they will provide a collective assessment of America’s groundwater availability.

New One-Stop Source for Scientific Information about U.S. Oceans and Waters

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 28 Jan 2010 16:57:15 EDT

A one-stop source for biogeographic information collected from U.S. waters and oceanic regions is now available from the National Biological Information Infrastructure (NBII) Program.

The OBIS-USA website offers a unique combination of tools, resources, and biodiversity information to aide scientists, resource managers and decision makers in the research and analyses critical to sustaining the nation’s valued marine ecosystems.

OBIS-USA was established in 2006 in cooperation with the U.S. National Committee for the Census of Marine Life a committee composed of renowned marine community leaders. OBIS-USA – a partnership of state, federal and scientific organizations -- is the United States’ contribution to the International Ocean Biogeographic Information System, an effort led by the Census of Marine Life to provide “open access” to global biodiversity data on the myriad of marine life that inhabits the ocean.

Sea angel (Clione limacina), the most common shell-less pteropod of arctic waters. Courtesy of the census of Marine Life Arctic Ocean Diversity project, © Kevin Raskoff. (Full size image)

Green sea turtle, Hawaii. Photo by Paul Wang. (Full size image)

“The world’s ocean is critically important, not only because of how it influences the climate, but also because it provides the resources for commercial, recreational, cultural, scientific, conservation, and national security activities,”” said John Mosesso, OBIS-USA co-lead. “At the same time, the ocean is threatened by a variety of changes, including warming temperatures, increasing ocean acidity, invasion by non-native species, overharvesting, and loss of habitat for species of concern.”

OBIS-USA provides data and functional tools to address key questions and information needs related to scientific understanding of sustainable and resilient ecosystems, marine spatial planning, climate change, ocean acidification, invasive species, and managing the nation’s fisheries. To address these ocean threats requires access to critical information on marine biodiversity, Mosesso noted.

OBIS-USA data holdings comprise millions of individual records supplied by marine data sponsors from across the nation. The site provides a work space for visitors to search and manipulate that data. This is accomplished in collaboration with data providers to produce a compilation of data in a common format. Data are interoperable and can be consistently viewed and applied by researchers, decision makers and resource managers.

Users can search and download data and metadata describing when and where species were observed or collected. The site’s offerings are available through an atlas (where users can review and select specific data sets). Individual or composite data sets (user-created selections from the entire holdings) may be viewed through several functions, including:

data dashboard - provides a pictorial view of data attributes that lets users assess their utility;
data richness - assesses how well the data are populated for selected elements;
data quality - provides key data collection information;
duplication status - indicates if a data set may contain duplicate records;
general metadata – displays the Federal Geographic Data Committee data record;
geographic coverage – displays data collection sites spatially;
participants - names OBIS-USA participants, with the option to connect back to the atlas, dashboard, and metadata functions; and
taxonomic depth - table shows the levels of taxonomic hierarchy for each organism.

OBIS-USA goals this year include an increase to over 10 million total data records and expanded functionality to address needs such as integration with non-biological data and further capability regarding species distributions.

To learn more about OBIS-USA, including growing its list of data and exploring partnerships, contact the NBII’s Mark Fornwall or John Mosesso.

Coordinated by the U.S. Geological Survey, the NBII is a broad, collaborative program to provide increased access to data and information on the nation's biological resources.

OBIS-USA screen shot showing 396 observations of sea angel (Clione limacina). (Data set searched: ArcOD - the Census of Marine Life Arctic Ocean Diversity project) (Full size image)

From Toxic Dust and Algae to Ill Winds From Africa

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 20 Nov 2009 10:02:25 EDT

USGS at the Society of Environmental Toxicology and Chemistry

Note to editors: The SETAC conference will be held in New Orleans from Nov. 19-23. For more info on the conference, visit their Web site.

Toxic dust: Toxins in coal-tar-based sealcoats in parking lots may be the culprit in contaminated house dust, according to a USGS study. PAHs – or polycyclic aromatic hydrocarbons – are large molecules found in oil, coal and tar deposits, and can have toxic effects. It’s long been known that PAHs are often found in house dust; however, the specific sources of these PAHs are largely undetermined. Researchers found that dust from indoor areas near parking lots with coal-tar-based sealcoat had substantially elevated concentrations of PAHs. This study, PAHs in house dust and relation to coal-tar-based pavement sealcoat, will be presented on Nov. 20 at 10:20 a.m. in the Belle Chasse Room. For more information, contact Barbara Mahler at bjmahler@usgs.gov or at 512-927-3566.

Eensy-weensy spiders play large role as sentinels of contaminants: Spiders that live near water may be an effective warning system for contaminants in aquatic ecosystems, according to a new USGS and U.S. Environmental Protection Agency study. Scientists examined PCB (polychlorinated biphenyls) levels in shoreline-living spiders at Lake Hartwell, a Superfund site in South Carolina, and used this information to map contaminant concentrations in lake sediment. Future monitoring studies will use the spiders as indicators of ecosystem recovery from PCB contamination. Researchers also made risk maps for a spider-eating bird, the Carolina wren, which could be exposed to PCBs through eating spiders. These spiders rely heavily on adult aquatic insects for food and play a key ecological role in the transfer of contaminants between water and land ecosystems. In spite of this, they are underused as a sentinel species at contaminated sediment sites. This study, using riparian spiders as sentinels of PCB export and risk, will be presented on Nov. 21 at 3:50 p.m. in the Versailles Room. To learn more, contact David Walters at waltersd@usgs.gov or at 970-226-9484.

It’s an ill wind that blows: African dust making it across the ocean: Increasing quantities of African dust have blown across the Atlantic Ocean to the Caribbean and Americas over the past few decades. During that time, the dust’s composition has changed. In this study, African dust air masses in Africa and the Caribbean were analyzed for persistent organic contaminants and metals. These potentially toxic contaminants can originate from the burning of plastics, biomass and waste; widespread use of pesticides, plastics, and pharmaceuticals; and increased industrialization. Multiple pesticides and other contaminants, including carcinogens, suppressors of immune systems, disruptors of endocrine systems, and nervous system or liver toxins were identified from all sample sites. All are known to persist in the environment, accumulate in organisms, and are toxic at very low concentrations. This study, Chasing clouds of dust: transoceanic transport of synthetic organic pollutants and trace metals with African dust, will be presented on Nov. 22 at 11 a.m. in Ballroom D. For more information, contact Ginger Garrison at ginger_garrison@usgs.gov or at 727-803-8747, ext. 3061.

Invasive carp and the secret language of scent: The chemical language of invasive Asian carp may eventually be turned against them in the fight to help eradicate these harmful invaders from the Mississippi River. Asian carp, introduced into the Mississippi River in the 1970s and 80s, are now abundant throughout the lower Missouri, the Mississippi and Ohio rivers, posing a threat to native species. Carp seem to have a chemical language effective for predator defense and reproduction in murky environments, so researchers put this language to the test by subjecting young carp to extracts prepared from the skins of other carp. The result: the young carp, upon detecting the extracts, significantly avoided them by moving from the area, becoming immobile, and schooling. This “alarm substance” may be effective in repelling carp from habitat critical to native species. Young carp were also attracted to the chemical stimuli of schooling carp, which can assist in conventional eradication methods. This study, Use of pheromones to control invasive Asian carp, will be presented on Nov. 20^tat 10:40 a.m. in the Elmwood Room. To learn more, contact Robin Calfee at rcalfee@usgs.gov or at 573-441-2969.

Toxic algae may be harming endangered suckers in Klamath Lake: Preliminary data suggest that algal toxins may be hindering the population growth of endangered Lost River suckers and shortnose suckers in Upper Klamath Lake in southern Oregon. This lake is characterized by high levels of nitrogen and phosphorus, nutrients that promote large, frequent cycles of cyanobacterial or algal blooms from spring through fall. Researchers evaluated the presence and effects of these toxins, specifically microcystins, which are harmful to other aquatic life, in the lake’s water and in fish from the lake. Examination of liver tissues from juvenile suckers revealed adverse physiological effects consistent with tissue damage associated with microcystin exposure. Significant concentrations of the toxins were reported form all field sampling stations in the lake. This study, Cyanobacterial toxins found in Upper Klamath Lake, Oregon: implications for endangered fish, will be presented on Nov. 22 at 1:10 p.m. in Ballroom C. To learn more, contact Kathy Echols at kechols@usgs.gov or at 573-876-1838.

Wading through the sources of lake contamination: Contamination of urban lakes and streams by polycyclic aromatic hydrocarbons (PAHs) is widespread and has been increasing over the last 40 years in the United States. These PAHs can be toxic to bottom-dwelling organisms, can cause tumors in fish, and several are believed to cause cancer in humans. In this study, researchers examined five sources of PAHs in 40 urban lakes from across the United States, including coal-tar-based pavement sealcoat, coal combustion, oil combustion, vehicle emissions and wood combustion. Of the five sources studied, sealcoat was the strongest contributor to PAH contamination in lake sediment. This research can help those trying to reduce pollution levels in the urban environment by providing them with a better understanding of PAH sources. This study, Sources of PAHs to urban lakes in the United States, will be presented on Nov. 23 at 11:20 a.m. in the Jefferson Room. For more information, contact Peter Van Metre at pcvanmet@usgs.gov or at 512-927-3506.

Tiny particles with big effects: Industrially produced nanoparticles are being dispersed into the environment from a range of everyday human activities. Use of consumer nanoproducts, such as sunscreen with zinc oxide or bed sheets and socks containing silver nanoparticles, all have the potential to release metals into the environment. Some of these particles can be toxic, but little is known about how nanoparticles will accumulate in the environment. Interactions between nanoparticles and living organisms are influenced by the unique physico-chemical properties of each kind of nanoparticle. This study introduces a new approach to evaluate the toxicity of nanoparticles with metal as an ingredient, and offers a way to begin to understand potential beneficial uses and potential environmental risks. This study, Characterizing the bioavailability and toxicity of engineered nanoparticles using enriched isotope tracers and biodynamic modeling, will be presented on Nov. 22 at 10 a.m. in the Oak Alley Room. For more information, contact Marie-Noele Croteau at mcroteau@usgs.gov or at 650-329-4424.

Cause of feminized male sturgeon remains elusive: The number of male shovelnose sturgeon with female characteristics in the Missouri River has increased from about 3 percent in 1968 to 15 percent in 2001. USGS researchers examined the levels of PCBs (polychlorinated biphenyls) and organochlorine pesticides in normal and intersex fish to see whether these hormone-mimicking compounds were associated with the condition. Although the compounds were all present in sturgeon at levels of concern, no differences in levels between intersex male fish and normal male fish were detected. Still, reproductive development is complex and can depend on many factors, including a fish’s age at its first exposure. These fish are also exposed to many other compounds that have not yet been tested. Recent findings of intersex in endangered pallid sturgeon underscore the need to find the cause of this condition. This study, Intersex gonads in Missouri River shovelnose sturgeon: occurrence, severity, and association with contaminants, will be presented on Nov. 22 at 8:40 a.m. in Ballroom A. To learn more, contact Diane Papoulias at dpapoulias@usgs.gov or at 573-999-1788.

Saving Sand: South Carolina Beaches Become a Model for Preservation

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 23 Oct 2009 9:33:00 EDT

The USGS report is available online.

While most people head to Myrtle Beach for vacation, a group of scientists have been hitting the famous South Carolina beach for years to figure out how to keep the sand from washing away.

Although they studied only a limited segment of beach, their work is a model for beach preservation that can apply elsewhere. And with talk of “balancing the sand budget” and money saved on restoration, their findings sound financial.

The study will be presented to scientists from around the world at the International Geological Programs Annual Conference, Oct. 25 to 31 in Myrtle Beach.

“Effective beach preservation requires knowing the beach’s sand budget and understanding the geology that constrains it,” said U.S. Geological Survey lead scientist Walter Barnhardt. “It takes a systematic approach and strong partnerships at all levels of government with neighborhood associations and universities to keep a beach from simply washing away.”

The main objective of this 7-year study, done in cooperation with the South Carolina Sea Grant Consortium, was to improve projections of coastal change by determining the geologic features and ocean processes that control sediment movement along the coast.

“As a result of this work, we were able to identify offshore sand sources that could be used for future beach replenishment without causing a bigger erosion problem elsewhere,” said Barnhardt.

Controlling beach erosion will likely become more difficult as a result of climate change with its attendant sea-level rise and increase in the number and intensity of storms. This is particularly true in places like South Carolina that have a broad, low-elevation coast and a sand shortage.

“The comprehensive nature of this study -- considering the geologic framework, behavior and driving processes regionally -- has resulted in a remarkable baseline for better managing our beach and near- shore resources,” said Paul Gayes, Director of Coastal Carolina University’s Center for Marine and Wetland Studies.

“From inventory of potential future beach nourishment sand resources, to distribution of important hardbottom fish habitat, to models of beach behavior, this study forms the starting point for many present and future efforts. This work is regularly cited as a model approach and result for similar studies and efforts around the country,” said Gayes.

For this study, scientists examined land and marine environments in a 62-mile-long segment of South Carolina’s coast. The swath extends more than 3 miles inland and 6 miles seaward. They tracked waves and sand movement, drilled cores, mapped the topography and geology onshore and offshore, and monitored coastal change.

Key Findings:

Sand is a scarce resource near Myrtle Beach
- The beaches are thin ribbons of sand that sit on top of sedimentary rocks. They receive little or no sand from nearby rivers.
- Offshore, there is little sand to wash ashore and replenish the beach. Large expanses offshore are exposed as hard grounds that are locally overlain by sand less than 3 feet thick.

Sand is transported primarily from northeast to southwest in the area. Large sand deposits have accumulated seaward of Murrell’s Inlet and Winyah Bay, SC. These and other sand deposits could serve as offshore sources of beach nourishment in the future.

Effective beach management requires a regional, systematic effort to
- understand the geology and how it constrains sand supplies and sand movement,
- determine patterns of shoreline change by surveying beaches at regular intervals over several years and
- identify ocean processes that drive coastal erosion.

A detailed record of coastal change provides guidance for land use and a rationale for development decisions such as determining setbacks necessary to protect property.

Climate change will affect many beaches; low elevation beaches are vulnerable over greater inland areas.

Coastal Change Along the Coast of Northeastern South Carolina – The South Carolina Coastal Erosion Study (USGS Circular 1339), is available online. Printed copies are available from the USGS Store (Product #222905)

The USGS conducts regional multidisciplinary studies of coastal erosion to provide impartial scientific information necessary for the protection and management of valuable coastal resources.