USGS Newsroom

New Insight on Gas Hydrates in Gulf of Mexico

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 14 May 2013 10:00:00 EDT

Research is Part of a Long-Standing, Interagency Collaboration

Scientists have returned from a 15‑day research expedition in the northern Gulf of Mexico with the best high-resolution seismic data and imagery ever obtained of sediments with high gas hydrate saturations.

The expedition and the data and imagery collected resulted from long-standing cooperation between the U.S. Department of the Interior's U.S. Geological Survey (USGS) and Bureau of Ocean Energy Management (BOEM) and the U.S. Department of Energy (DOE). This collaboration aims to advance scientific understanding of gas hydrates, an important potential future energy resource.

Gas hydrates are ice-like substances formed when certain gases combine with water at specific pressures and temperatures. Deposits of gas hydrates are widespread in marine sediments beneath the ocean floor and in sediments within and beneath permafrost areas, where pressure-temperature conditions keep the gas trapped in the hydrate structure. Methane is the gas most often trapped in these deposits, making gas hydrates a potentially significant source for natural gas around the world.

"This expedition represents a significant milestone," said USGS Energy Resources Program Coordinator Brenda Pierce. "The data and imagery provide insight into the entire petroleum system at each location, including the source of gas, the migration pathways for the gas, the distribution of hydrate-bearing sediments, and the traps that hold the hydrate and free gas in place. The USGS has a globally recognized research effort studying gas hydrates in settings around the world, and this project combines our unique expertise with that of other agencies to advance research on this potential future energy resource."

The recently completed expedition was planned jointly by USGS, DOE, and BOEM, and was executed by USGS. Using low-energy seismic sources, USGS scientists collected details about the nature of the gas hydrate reservoirs and about geologic features of the sediment between the reservoirs and the seafloor. The new data also provide information about how much gas hydrate exists in a much broader area than can be determined from using standard industry seismic data, which is typically designed to image much deeper geologic units.

"Understanding the nature and setting of deepwater gas hydrates is central to the National Methane Hydrates R&D Program, which is led by DOE and managed by Fossil Energy's National Energy Technology Laboratory," said Christopher Smith, DOE’s Acting Assistant Secretary for Fossil Energy. "Over the past 8 years, research carried out under this program has resulted in significant advances in our understanding of methane hydrates, their role in nature, and their potential as a future energy resource. This success is largely due to an unprecedented level of cooperation among federal agencies, industry, national laboratories, and academic institutions."

"The high-resolution nature of the data acquired through this interagency project will uniquely inform the BOEM effort to assess the resource potential of gas hydrates on the U.S. Outer Continental Shelf," said Renee Orr, Chief, Strategic Resources Office, BOEM.

The data were collected at two locations in the Gulf of Mexico where the three federal agencies partnered with an industry consortium to conduct a drilling expedition in 2009. That expedition discovered gas hydrate filling between 50 and 90 percent of the available pore space between sediment grains in sandy layers in the subsurface. These reservoirs are expected to be representative of the 6,700 trillion cubic feet of gas that BOEM estimates is housed in gas hydrates in sand-rich reservoirs in the northern Gulf of Mexico.

The new data are being used to refine estimates of the nature, distribution, and concentration of gas hydrate in the vicinity of the 2009 drill sites. This will help assess how useful specialized seismic data may be to estimating hydrate saturations in deepwater sediments.

In coming years, the three agencies will continue their collaborative investigation of gas hydrates in the northern Gulf of Mexico and other locations across the world.

Learn more about USGS research on gas hydrates and energy at locations around the world.

Stars show the locations of seismic surveys conducted to image previously-identified deepwater gas hydrate deposits in the northern Gulf of Mexico on the research ship Pelican during a cruise in April and May 2013. (Larger image)

This high-resolution image was collected during a seismic cruise to study locations with high concentrations of gas hydrate in the northern Gulf of Mexico in April and May 2013. The data were collected at the Walker Ridge location, where 2009 drilling at the site of the well (shown in red revealed) the distribution of gas hydrates and methane gas in the sediments. The water depth at the well is 6562 feet, and the red and blue colors shown within the image correspond to sediment layers, which mostly dip westward. Sand layers with high concentrations of gas hydrate are marked, but hydrate also occurs elsewhere in this sedimentary section. (Larger image)

USGS Flyover Shows Storm Damage and Marsh Dieback

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 11 Sep 2012 9:00:00 EDT

A flyover of southeast Louisiana revealed storm damage from Hurricane Isaac and marsh dieback, some of which was occurring before Hurricane Isaac. The flyover was conducted by the U.S. Geological Survey National Wetlands Research Center (NWRC), U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture Natural Resources Conservation Service.

The flight examined areas from Wax Lake Delta, La., to Ship Island, Miss., and preliminary assessments suggest that Hurricane Isaac damaged coastal wetlands in a manner that is substantial, but not unprecedented. Damage to coastal wetland areas was evident throughout much of southeast Louisiana. The intensity of hurricane effects was most abundant in areas of upper Breton Sound, an area just to the south of the community of Braithwaite, which experienced devastating flooding. Breton Sound had been experiencing some slight recovery from the extensive damage inflicted by Hurricanes Katrina and Gustav; however, scientists observed many of the initial effects of Hurricane Isaac to be reactivations of previous damages in these newly recovering areas. Photos from the flyover are available online.

"The before and after images from coastal flyovers reveal the disappearance of some of the Gulf's most biologically and economically significant landscape disappearing before our very eyes, on human time scales," said USGS Director Marcia McNutt. "There are many compounding factors that lead to enhanced coastal vulnerability, with hurricanes sweeping in to deliver the coup de grace."

Other areas in which physical damage to coastal wetlands was observed include the north shore of Lake Pontchartrain near Slidell, areas surrounding the Rigolets to include the mouth of the Pearl River, and the Chandeleur Islands. The majority of structural changes in these areas appear to be reactivations or intensifications of effects of previous storms. Previous storms such as hurricanes Audrey, Hilda, Betsy, Andrew, Katrina, Rita, Gustav, and Ike are known to have damaged coastal wetlands and contributed to wetland loss, and Isaac appears to have been yet another blow to Louisiana's fragile but vital coastal wetlands.

"Louisiana's coastal land loss is the greatest environmental, economic and cultural tragedy on the North American Continent, and marsh dieback exacerbates this ongoing disaster," said USGS NWRC Director Phil Turnipseed. "The NWRC is dedicated to continuing to investigate the causes of land loss in order to provide decision makers with information that can help reduce land loss in the future."

The most prevalent effects of Hurricane Isaac observed were expansive wrack fields. Wrack is accumulated organic debris and trash that are transported and deposited by a hurricane’s surge. Wrack deposits from Hurricane Isaac were observed throughout southeast Louisiana, burying existing marsh areas and obstructing infrastructure, such as canals and railroads. Generally wrack deposits eventually decompose and the areas are re-vegetated, but in the short-term wrack can kill the existing wetland vegetation.

Very few downed trees were observed in forested wetlands from Hurricane Isaac, especially compared to that of Hurricane Katrina, which is likely indicative of the lesser intensity of this storm. Even in areas where no physical removal of wetlands or vegetation was evident, the vegetation which did survive was observed to have sustained substantial damage.

Large areas of marsh dieback, termed "brown marsh" or "sudden marsh dieback," were observed in the Terrebonne and Barataria basins in Louisiana. Previous reports of sudden marsh dieback in the spring and summer of 2012, before Hurricane Isaac, indicate that the dieback in this area has been increasing over time and may be the result of a combination of other stressors. Evidence of vegetation stress, such as widespread discoloration, was also observed in areas that were directly impacted further to the east by hurricane storm surge. The browning and destruction in the marshes east of the Mississippi River in coastal Louisiana appear to be recent, indicating a more direct link to salinity and flooding stress associated with the Hurricane Isaac's storm surge. The USGS will further investigate the recent history of sudden marsh dieback events in coastal Louisiana. Subsequent aerial surveys will be conducted to quantify the extent of brown marsh and to potentially separate the phenomenon of sudden dieback and the storm surge impacts.

Sudden marsh dieback events have occurred over the last decade in coastal marshes from the Northern Gulf of Mexico to Maine. One of the most severe events occurred in 2000, where almost 25,000 acres (about 400 square miles) of salt marsh were impacted throughout Louisiana’s Mississippi River Delta Plain. The cause of sudden marsh dieback is still under debate, but may be cyclical depending on interactive climate conditions, sea level changes, and other environmental factors.

Marsh dieback can lead to land loss since the roots of the plants help hold the marsh together and, in some cases, increase the elevation of the marsh. As the plants die, the elevation of the marsh sinks when the roots deteriorate, turning marsh to shallow open water.

Louisiana currently experiences more wetland loss then all other states in the U.S. combined. Coastal Louisiana has lost a wetland area the size of Delaware, equaling 1,883 square miles, over the past 78 years, according to a 2011 USGS National Wetlands Research Center study.

Visit NWRC's hurricane research for more information. To view images collected during post-Hurricane Isaac reconnaissance flights, click on the Hurricane Isaac link. To learn more about brown marsh, visit the Coastal Marsh Dieback (Brown Marsh) website.

USGS Helps Assess Tangipahoa Dam Health

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 7 Sep 2012 14:08:42 EDT

JACKSON, Miss. – The U.S. Geological Survey mapped the damage caused to Tangipahoa Dam in 3-D earlier this week, using new technology to get a detailed view of the troubled dam. The dam was damaged during heavy rainfall in Hurricane Isaac and caused thousands of people downstream to be evacuated late last week.

Using terrestrial lidar, or T-lidar, the crew captured multiple scans of the dam, including two large landslides on its downstream side. In the larger of the two slides, much of the base of the slide was still underwater and necessitated the use of a kayak-towed acoustic Doppler profiler to measure the toe of the slide.

The first T-lidar scans took place Saturday, with more completed on Monday to assess whether additional movement of the slides had occurred. Monday's scan showed little change; information that has been provided along with other data to the U.S. Army Corps of Engineers as they continue to address the issue.

"We were fortunately already mobilizing this fabulous 3-D imaging technology when our field crews learned of the need to monitor the stability of the Tangipahoa Dam," said USGS Director Marcia McNutt. "I know of no other technology that could compete with T-lidar for providing both the precision and ease of deployment or that has the potential to determine whether a structure is in danger of failing when time is of the essence."

Isaac is the first storm in which USGS has used its terrestrial lidar capabilities to map urban flooding.

"We brought our T-lidar capabilities into the area affected by Isaac as part of a pilot project to assess its use for mapping flood levels in urban areas, and to develop flood inundation maps that will help forecast future flood effects," said Toby Minear, a research hydrologist at the USGS California Water Science Center, who completed the scans of the dam. "What we've found is that, not only can it help assess current flood levels and high-water marks, it has the potential to play a pivotal role in helping assess the health of structures threatened by floodwaters, providing critical information to those who need it in a matter of minutes."

T-lidar allows scientists to quickly generate 3-D maps of buildings, dams, levees and other structures, and can show areas of storm damage as well. In a four-to-five minute scan, the instrument collects millions of topographic data points in a full 360-degree view to quickly produce highly accurate topographic information and can map areas up to two-thirds of a mile away.

Acoustic Doppler instruments, such as the one used to map the underwater portion of the slide at Tangipahoa Dam, are frequently used to measure stream or lake geometry and water velocity. An acoustic signal is bounced off the river or lake bottom and the amount of time required for the signal to return to the sensor provides a measurement of the distance to the bottom.

USGS crews also deployed storm surge sensors just below the dam, and at four bridge crossings downstream between the dam and the USGS' real-time permanent streamgage on the Tangipahoa at Osyka. The sensors allowed the USGS to monitor river levels as actions were taken to release the pressure on the dam and reduce water levels.

3-D Mapping of Isaac Water Levels

OC_Web@usgs.gov (Office of Communications and Publishing) — Sat, 1 Sep 2012 11:34:38 EDT

3-D Mapping of Isaac Water Levels

A new technology is being deployed by U.S. Geological Survey scientists this weekend to map urban flooding caused by Hurricane Isaac. Called “terrestrial lidar,” or “T-lidar”, this new capability will enable scientists to collect highly detailed information in select population areas in Louisiana, Mississippi, and Alabama where the hurricane had the greatest impact.

The portable instrument allows scientists to quickly generate 3-D maps of buildings, dams, levees and other structures, and can show areas of storm damage as well. In a four-to-five minute scan, the instrument collects millions of topographic data points in a full 360-degree view to quickly produce highly accurate topographic information and can map areas up to two-thirds of a mile away.

The information gathered from this pilot project will be used by USGS to develop 3-D models of streets and structures, including the levels floodwaters reached, as well as current water levels in the form an interactive 3-D flood inundation map. The map will help identify where the potential threat of future floodwaters is greatest, and will help determine the extent of wind and flood damages caused by Isaac.

"If a picture paints a thousands words, a T-lidar scan paints several million words to capture the fleeting aftermath of a hurricane's impact," said USGS Director Marcia McNutt. "The ability to rapidly preserve for posterity a quantifiable, three-dimension representation of storm damage is going to open the doors for new flood hazard science."

T-lidar looks sideways from ground level, enabling it to capture vertical details, such as water levels, that airborne lidar cannot. This enables it to capture the extent of flooding. The USGS will be using both a tripod mounted and a truck-mounted version. While the tripod version takes individual scans from multiple locations that later have to be combined to develop its 3-D maps, the truck-mounted version is continuously collecting information that is available almost immediately.

"Using terrestrial lidar in this fashion has the possibility of helping us quickly assess high-water marks, current water levels, and to some degree flood damage, in a very short time," said Athena Clark, director of the USGS Alabama Water Science Center. "We’re always looking for better, more efficient and cost effective ways of advancing the science and this technology has some great possibilities."

"Lidar" stands for "light detection and ranging." Where "radar" uses radio waves as a form of measurement, "lidar" uses light. Terrestrial lidar, sometimes called “terrestrial laser scanning,” uses a sensor that emits laser pulses and measures distance by how long it takes the reflected laser beam to "bounce back" to the instrument. TLS can provide very precise data, to millimeter accuracy, to enable scientists to build high-resolution 3-D models of objects.

"We are collecting storm-tide information that will allow scientists to study the impacts of the storm in three dimensions," said Toby Minear, a research hydrologist at the USGS California Water Science Center, who is participating in the study. "Imagine a 360-degree panoramic photo, but made with laser points where everything you can see has a known elevation and location. These 'point clouds' can be put together to create a full 3-D map of an area containing many millions of data points."

In addition to the use of terrestrial lidar, the USGS is also planning airborne lidar flights to assess the level of coastal change caused by Isaac along the Gulf Coast. More information on both these studies will be released when they are completed.

Media Advisory: Measuring the Impact of Isaac

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 30 Aug 2012 10:45:21 EDT

Media are invited to join U.S. Geological Survey crews working in areas impacted by Isaac as they retrieve storm-tide sensors deployed prior to the storm, measure high-water marks, make inland flood measurements, and collect water samples to measure water quality following the storm.

The storm-tide sensors will be retrieved from Mobile Bay in Alabama to Breton Sound in Louisiana, including Lake Pontchartrain. The sensors were installed to measure the storm-tide height and intensity of Hurricane Isaac. The information will help define the depth and duration of the storm-tide, as well as the time of its arrival and retreat. That information will help assess storm damage, discern between wind and flood damage, and improve computer models used to forecast future floods.

As Isaac moves inland, flooding from the drenching rains becomes an issue, and as the storm progresses northward, additional measurements will be required in the Midwest states.

What: Reporters can accompany the USGS crews as they retrieve the storm-tide sensors, measure high water marks, and collect water samples from various locations along the Gulf Coast. USGS crews will also be making flood measurements at affected streamgages inland from the coast that are critical for accurate flood forecasts.

Points of Contact:

• Louisiana:	George Arcement	(225) 978-4203
• Mississippi	Michael Plunkett	(601) 933-2940
• Alabama:	Athena Clark	(334) 395-4141

When/Where: The specific schedules and locations will vary by state depending on flooding and road closures. Contact the state point of contact for more information.

Additional information on USGS activities before, during and after the storm can be found on the USGS website.

Mississippi River Flows Backwards Due to Isaac

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 29 Aug 2012 17:27:16 EDT

Strong winds and storm surge from Hurricane Isaac's landfall forced the Mississippi River to flow backwards for nearly 24 hours on Tuesday, August 28. The USGS streamgage at Belle Chasse, Louisiana, showed the Mississippi River flowing upstream at 182,000 cubic feet per second, surging to 10 feet above than its previous height. Average flow for the Mississippi River at Belle Chase is about 125,000 cfs towards the Gulf of Mexico.

Although it doesn't happen often, hurricanes can cause coastal rivers to reverse flow. Between the extremely strong winds and the massive waves of water pushed by those winds, rivers at regular or low flow are forced backwards until either the normal river-flow or the elevation of the land stop the inflow.

As Hurricane Isaac pushes further inland, it is causing storm surge in the Mississippi River as far north as Baton Rouge, where the river has crested at 8 feet above its prior height.

"This reversal of flow of the mighty Mississippi is but one measure of the extreme force of Isaac," said USGS Director Marcia McNutt. "While such events are ephemeral, they are yet another reminder of why we need to respect hurricane warnings."

When Hurricane Katrina came ashore in 2005, the Mississippi River also reversed flow, cresting at 13 feet above its previous level, with Baton Rouge reaching 9 feet above its previous stage as well.

Another phenomenon that USGS streamgages have recorded as Hurricane Isaac moves inland is that periodically, coastal rivers in Louisiana have lost height, only to gain it back again soon after. This rising and falling of the rivers is a common occurrence during hurricanes and is caused by the spiral nature of these storms.

As the winds sweep to the southwest, they force water out of the rivers, lowering their height. However, once the winds complete their turn to the southwest, they begin back to the northeast, allowing the storm surge to raise the river levels.

These oddities in river behavior are recorded in real-time by USGS' extensive network of streamgages, located through Louisiana and the rest of the country. These streamgages, which are installed along rivers and streams, record data like streamflow, river height, and, in some cases, even water chemistry.

Many transmit their data in real-time to satellites, updating with new information every 15 minutes. This wealth of data allows USGS scientists, emergency managers and responders, and even the general public to have accurate and up-to-date knowledge of what the rivers and streams in their areas are doing. This data is particularly critical during massive flooding events like Hurricane Isaac.

In fact, anyone can sign up to receive notices from USGS streamgages when waters are rising in nearby rivers and streams through a program called WaterAlert. It is a free service that allows members of the public to receive notifications about water levels at any of over 7,000 USGS real-time streamgages around the country. Learn more about how to sign up here.

All USGS streamgage information is housed online. For Hurricane Isaac, USGS has compiled a list of all streamgages in affected areas here.

For the latest forecasts on the storm, listen to NOAA radio. For information on preparing for the storm, visit Ready.gov or Listo.gov

This velocity hydrograph shows the velocity of the Mississippi River during Hurricane Isaac’s landfall. On August 28, the velocity begins to approach negative velocity as high winds and storm surge cause the river to reverse flow. By the end of August 28, the river had regained its regular flow. The USGS streamgage that recorded this information is located at Belle Chasse, LA.

USGS Storm-Surge Sensors Deployed Ahead of Isaac

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 28 Aug 2012 17:59:21 EDT

Hurricane response crews from the U.S. Geological Survey are installing more than 120 storm-tide sensors at key locations along the Gulf Coast from the Florida Panhandle to Louisiana in advance of the arrival of Hurricane Isaac.

The storm-tide sensors, frequently called storm-surge sensors, will be secured to piers and poles in areas where the hurricane is expected to make landfall. The instruments being installed will record the precise time the storm-tide arrived, how ocean and inland water levels changed during the storm, the depth of the storm-tide throughout the event, and how long it took for the water to recede.

"While every hurricane brings the possibility for devastation, it also brings a learning opportunity by capturing valuable scientific data that improves our understanding of the pattern and timing of storm-driven coastal inundation," said USGS Director Marcia McNutt. "This vital information will help reduce loss of life and property now and in future events."

Storm-tides are increases in ocean water levels generated at sea by extreme storms and can have devastating coastal impacts. In locations where tidal forecasts are known, the sensors being installed can also help determine storm surge. For differences between storm-surge and tidal-surge, visit the National Hurricane Center's website.

This information will be used to assess storm damage, discern between wind and flood damage, and improve computer models used to forecast future coastal inundation.

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.

Of the sensors deployed, 12 of those have real-time capability that will allow viewing of the storm-tide as Hurricane Isaac approaches and makes landfall. The real-time gauges have water level, precipitation and wind sensors that will transmit all data hourly. All gauge data can be found at the USGS Storm-Tide Mapper.

Providing information to support future forecasts could ultimately save lives during future storms. These sensors were deployed for the first time during Hurricane Rita in 2005. Before then, scientists had limited data available to study the effects of storm surge.

"Forecasters at the National Weather Service rely on USGS real-time and long-term data for input into its predictive models that are used to improve storm surge models and prepare storm-tide warnings," said Brian McCallum, assistant director of the USGS Georgia Water Science Center. "Floodplain managers, federal, state and local emergency preparedness officials, emergency responders, scientists and researchers all benefit from the storm-tide and associated flood data. It’s useful for flood damage prevention and public safety."

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 also continuously monitors water levels and flows at thousands of the nation's streams on a real-time basis. The public can access this information for their area at the USGS Current Streamflow Conditions web page. Also, USGS WaterAlert allows users to receive a text or email from the USGS when waters are rising in rivers and streams near them.

For the latest forecasts on the storm, listen to NOAA radio. For information on preparing for the storm, visit Ready.gov or Listo.gov

Isaac Expected to Change Sandy Coasts from Louisiana to Florida

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 28 Aug 2012 16:58:32 EDT

Sandy beaches and barrier islands along the northern Gulf of Mexico are highly vulnerable to beach and dune erosion as Hurricane Isaac makes landfall this week, according to a new U.S. Geological Survey assessment. The projections also show which coastal areas may see storm-surge topping sand dunes and beaches.

Probabilities for coastal change have been calculated for parts of the Louisiana, Mississippi, and Alabama coastlines and for the Florida Panhandle.

On Saturday, the USGS released an assessment of expected coastal change in Florida, but the change in the storm’s path has reduced the concern for erosion of west central Florida beaches, shifting focus primarily to sandy beaches and barrier islands from Florida’s Panhandle to Louisiana.

Beaches and dunes can serve as a first line of defense for residents on coasts exposed to these types of storms. During tropical storms and hurricanes, elevated water levels and waves can lead to dramatic coastal change. According to the latest USGS research, during even the weakest hurricanes, wave height and storm surge combine to increase water levels along the Gulf Coast shoreline by 14 and a half feet higher than their normal levels.

"We can now combine more accurate coastal data with powerful new scientific models to provide the very best predictions of hurricane surge, waves, and erosion," said USGS Director Marcia McNutt. "USGS scientists used the latest NOAA forecasts to ensure that the people of the Gulf Coast are not surprised by the impacts of Isaac."

Using a USGS-developed model, scientists incorporated measurements of beach elevation and wave and surge forecasts from the National Oceanic and Atmospheric Administration to determine the probabilities of collision, overwash and inundation during the coming storm.

Collision is when waves attack the base of dunes and cause dune-front erosion. Overwash occurs when waves and storm surge overtop dunes and transport sand landward. Inundation, the most extreme of the three, occurs when increased water levels completely submerge beaches and dunes.

"Earlier this year, USGS released a report detailing hurricane induced erosion hazards for category 1-5 storms. The predictions released this week are based on the same methods, but tailored to waves and storm surge specific to Hurricane Isaac," said Hilary Stockdon, USGS research oceanographer. "As the storm moves across the Gulf, we use real-time storm and wave forecasts from NOAA to determine where beach erosion and inundation are most likely to occur."

These predictions, available on the USGS Hurricanes and Extreme Storms website, show the probable impacts of Isaac at each location along the coast. This assessment may be updated if there are significant changes in the storm’s projected track or strength. Based on the current assessment, the percentages of each type of coastal change were estimated for each of the following states:

Louisiana

Beach and dune erosion is very likely for 66 percent of Louisiana's sandy beaches
29 percent of the sandy beaches in this area are very likely to experience overwash.
18 percent of the Louisiana's barrier islands are expected to be inundated; however, the majority of this inundation will occur only on Louisiana's Chandeleur Islands.
100 percent of the Chandeleur Islands are very likely to experience overwash and 83 percent of these islands are very likely to be inundated. This beach system was devastated during Hurricane Katrina, making it more vulnerable to-low intensity storms.

Mississippi

Beach and dune erosion is very likely for 89 percent of Mississippi's sandy beaches and barrier islands.
20 percent of the sandy beaches are very likely to experience overwash.
Inundation of the beach system is not expected.

Alabama

Beach and dune erosion is very likely for 52 percent of Alabama's sandy beaches and barrier islands.
11 percent of the sandy beaches are very likely to experience overwash.
3 percent of the sandy beaches are very likely to be inundated

Florida Panhandle

Beach and dune erosion is very likely for 32 percent of the Panhandle's sandy beaches
2 percent of the sandy beaches are very likely to experience overwash.
Inundation of the beach system is not expected.

After the worst of the storm passes, USGS may send teams to the field to measure the impact of Hurricane Isaac on the coastline.

Aerial photography and elevation surveys of post-storm beach conditions are used to document the impacts of hurricane waves and currents on the beach. Information obtained from the surveys allows scientists to discern the degree of changes to beaches and coastal environments and determine how much the land has eroded and where new inlets have cut through. The newly acquired data will also be used to make more accurate predictive models of future coastal impacts from severe storms and identify areas vulnerable to extreme coastal change.

The areal photos can visually demonstrate the severe impacts of hurricane surge on beaches. This photo shows the effects that hurricane waves and surge have had on Dauphin Island, Alabama from 2004 -2008.

In May, the USGS released a report assessing probability of coastal change for the Gulf Coast when facing hurricanes of different strengths. The report included an interactive map that allows users to focus on different parts of the Gulf Coast shoreline to view how the probability of erosion, caused by waves and storm surge, will vary depending on hurricane intensity.

For the latest forecasts on the storm, listen to NOAA radio. For information on preparing for the storm, visit Ready.gov or Listo.gov

Florida Beaches and Dunes Face Erosion Risk During TS Isaac

OC_Web@usgs.gov (Office of Communications and Publishing) — Sat, 25 Aug 2012 14:30:00 EDT

USGS Calculates Likelihood of Coastal Changes

ST. PETERSBURG, Fla. – Seventy-eight percent of Florida's west central coast and 23 percent of the Panhandle are very likely to face beach and dune erosion as Tropical Storm Isaac moves into the area early next week, according to an assessment released by the U.S. Geological Survey on Friday. These numbers are likely to increase if the storm reaches hurricane strength as predicted.

For many Florida beaches that had significant erosion during Tropical Storm Debby in June, the impact of additional erosion may be even more significant.

"With Isaac bearing down on Florida beaches so soon on the heels of Debby, this is like a 'one-two punch' for the dunes that provide coastal protection," said USGS Director Marcia McNutt. "As these sand dunes dynamically morph to new configurations, our science-based models can help in forecasting where communities are at most risk from storm damage in this ever-changing spatial and temporal pattern of storm intensity and coastal morphology."

During tropical storms and hurricanes, elevated water levels and waves can lead to dramatic coastal change through erosion of beaches and dunes. These beaches and dunes can serve as a first line of defense for residents for many coasts exposed to these types of storms.

Using a USGS-developed model scientists incorporated measurements of beach elevation and wave and surge forecasts from the National Oceanic and Atmospheric Administration to determine the probabilities of collision, overwash and inundation during the coming storm.

"Tropical Storm Debby eroded many beaches along Florida's west central coast, impacting the property of many gulf-side residents and hotels," said Hilary Stockdon, a USGS oceanographer and lead of the assessment team. "Beaches typically take years to recover from severe storm impact, so having what is likely to be a Category 1 or 2 hurricane move up the coast just two months later could take a heavy toll on some already heavily eroded areas."

In addition to the likelihood of erosion, the team found that 15 percent of the west central coast was very likely to face overwash should the storm make direct landfall there, while that likelihood was only 5 percent for the Panhandle where dune elevations are higher. Unless forecasts change significantly, inundation is not expected in either area.

The team will revise its calculations as storm track and intensity forecasts are updated, and will update their projections and website accordingly. They plan to include the Alabama and Mississippi coasts in their assessments this weekend. Additional information on coastal change and extreme storms can be found on the USGS Coastal Change Hazards website.

The research is expected to help emergency managers at local, state and federal levels as they prepare for hurricane events such as this one in this and future seasons. Planners will be able to determine how different categories of hurricanes would impact their beaches and surrounding communities, helping them better protect lives and property.

For the latest forecasts on the storm, listen to NOAA radio. For information on preparing for the storm, visit Ready.gov or Listo.gov.

New Louisiana Water Use Report Available

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 21 Aug 2012 8:00:00 EDT

New statistics on the use of water in Louisiana are presented in a recent report by the United States Geological Survey.

In 2010, approximately 8,500 million gallons of water per day (Mgal/d) were withdrawn from ground and surface-water sources in Louisiana.

The report, "Water Use in Louisiana, 2010," presents statistics on water withdrawn from ground and surface-water sources for various uses. The USGS, in cooperation with the Louisiana Department of Transportation and Development, has collected and published water withdrawal and use information on a five-year basis since 1960. The full report, as well as previous reports and water-use data, is available online.

"The current drought, which is affecting large portions of the nation, has highlighted the importance of products such as this new report for Louisiana showing trends in surface and groundwater usage over time and by sector," said USGS Director Marcia McNutt. "This information is critical for managers and planners in understanding how changes in factors such as population, industry mix, and crops affect water consumption."

Total groundwater withdrawals in Louisiana were 1,600 Mgal/d and total surface-water withdrawals were 6,900 Mgal/d. Forty percent (about 650 Mgal/d) of all groundwater withdrawn was from the Chicot aquifer system in southwestern Louisiana, and 25 percent (about 390 Mgal/d) was withdrawn from the Mississippi River alluvial aquifer. About 72 percent (5,000 Mgal/d) of all surface water withdrawn was from the Mississippi River mainstem. Water withdrawal totals for various categories of use were as follows: public supply, 750 Mgal/d; industry, 2,100 Mgal/d; power generation, 4,400 Mgal/d; irrigation, 930 Mgal/d; and all other uses, 350 Mgal/d.

The latest numbers indicate that total withdrawals in Louisiana have decreased by 17 percent since 2005. During that period, the State's population increased by 0.2 percent and total public withdrawals increased by approximately 3.8 percent. Pierre Sargent, of the USGS in Baton Rouge, attributes the overall decline in water use to a decrease in industrial withdrawals of 33 percent, a decrease in power generation withdrawals of 14 percent, and a decrease in total rice irrigation withdrawals of 13 percent for the same period. The decline in rice irrigation withdrawals is similar to a decrease of rice-harvest acreage by approximately 16 percent from 2005 to 2010.

The report also presents water-use trends in Louisiana from 1960 to 2010 based on data collected and reported every five years. Overall, since 1960, groundwater withdrawals have increased by 56 percent, surface-water withdrawals have increased by 58 percent, and total withdrawals have increased by 57 percent. However, for the period 1980 to 2010, total groundwater withdrawals decreased by 9.2 percent, total surface-water withdrawals decreased by 35 percent, and total withdrawals decreased by 31 percent (about 3,900 Mgal/d).

The USGS’s National Water-Use Information Program is responsible for compiling and disseminating the nation's water-use data. The USGS works in cooperation with local, State, and Federal environmental agencies to collect water-use information. USGS compiles these data to produce water-use information aggregated at the county, state, and national levels. Every five years, data at the county level are compiled into a national water-use data system and state-level data are published in a national circular.

New Maps for CA, LA and MS Rolling Out

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 5 Jun 2012 7:44:13 EDT

California, Louisiana and Mississippi join the more than 40 states covered by the US Topo

In response to the need for up to date map coverage of the United States, the U.S. Geological Survey (USGS) has developed a national map series named the US Topo.With approximately 48,000 new digital maps currently available for free download, more than 4,300 revised quadrangles representing the states of California, Louisiana and Mississippi have been added to the ever-growing collection.

"Anyone who has ever been misrouted on account of outdated software in a GPS navigator can appreciate that maps are constantly in need of updating because both the human and the physical environment are ever changing," said USGS Director Marcia McNutt. "Our new US Topo map series allows users to get the latest data, select just the information of interest for download, and did I emphasize FREE?!"

New feature additions and improvements on the updated US Topo include:

Contours
Rivers, lakes steams and other hydrography
Woodland tint derived from the National Land Cover Dataset
Fire Stations
Hospitals
State and County boundaries
Forest service boundaries
Commercial roads in lieu of Census roads
Forest Service roads and road numbers

US Topos are derived from key layers of geographic data found in The National Map which delivers visible content such as high resolution aerial photography, which is not available on older paper-based topographic maps. The US Topo also provides modern technical advantages over the original lithographic map as it supports wider and faster public distribution and enables on-screen geographic analysis for users.

Future enhancements to the US Topo are scheduled to include additional functional capabilities and content, such as a shaded relief layer, Public Land Survey System (PLSS) data, updated structures, enhanced transportation, additional federal boundaries, and Forest Service trails. The USGS expects to produce more than 18,500 revised quadrangles annually, which means each US Topo map is updated every three years in a cyclic fashion.

The new digital electronic topographic maps of California, Louisiana and Mississippi – along with 37 other completed states - are now available for free download from the USGS Store. The quadrangles are delivered in GeoPDF format and may be viewed using Adobe Reader software, also available as a no cost download.

Gulf Coast Vulnerable to Extreme Erosion in Category 1 Hurricanes: New Model to Help Community Planners, Emergency Managers

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 30 May 2012 8:30:00 EDT

Seventy percent of the Gulf of Mexico shoreline is vulnerable to extreme erosion during even the weakest hurricanes, according to a new report by the U.S. Geological Survey released just prior to the start of the 2012 hurricane season.

USGS scientists used state-of-the-art modeling to determine the probabilities of erosion, overwash and inundation during direct hurricane landfall for sandy beaches along the entire U.S. Gulf Coast shoreline.

The research is expected to help emergency managers at local, state and federal levels as they prepare for hurricane events in this and future seasons. Planners will be able to determine how different categories of hurricanes would impact their beaches and surrounding communities, helping them better protect lives and property. The report also includes an interactive map that allows users to focus on different parts of the Gulf Coast shoreline to view how the probability of erosion, caused by waves and storm surge, will vary depending on hurricane intensity.

"The Gulf Coast's beaches provide abundant recreational opportunities, contribute substantially to the local economy, and demand the highest real estate values," said USGS Director Marcia McNutt. "This important research raises awareness on the specific nature of the vulnerability of these beautiful beaches to impacts from even Cat-1 hurricanes so that property damage can be minimized through proper planning."

In a storm, high waves and storm surge can act together to erode beaches and inundate low-lying lands; during hurricane landfall, these changes can sometimes be catastrophic.

"Beaches along the Gulf of Mexico are extremely vulnerable to erosion during hurricanes, in part, because of low elevations along the coast," said Hilary Stockdon, a USGS research oceanographer and lead author of the study. "For example, the average elevation of sand dunes on the west coast of Florida is eight feet. On Florida’s Atlantic coast, the average is 15 feet."

During the landfall of a category-1 storm, where winds are between 75 and 94 miles per hour, overwash is very likely for 70 percent of Gulf Coast beaches. Overwash occurs when waves and storm surge overtop dunes and transport sand landward. Overwash is likely at these locations because of increased water levels at the shoreline. During category-1 hurricane events on the Gulf Coast, wave height and storm surge combine to increase water levels at the shoreline by 14 and a half feet higher than their normal levels.

"People continue to build communities in coastal areas that shift and move with each passing storm," said Stockdon. "This model helps us predict the potential impact of future storms and allows us to identify where the most vulnerable areas are located along the coast."

Additional findings from the report show that during a category-1 storm landfall, 27 percent of sandy beaches along the U.S. Gulf of Mexico are projected to be inundated, which occurs when increased water levels completely submerge beaches and dunes. If category-5 storms occur, where winds are 157 miles per hour or higher, 89 percent of these beaches are likely to be inundated during a direct landfall.

USGS scientists used methodology developed from a decade of USGS research on storm-driven coastal change hazards as the basis for these calculations. Observational data were combined with sophisticated hydrodynamic modeling to predict the coastal changes provided in the report. As new data and storm predictions become available, the report's analysis will be updated to describe how coastal vulnerability may change in the future.

Key findings and the full report are available online.

A similar report detailing erosion hazards along the east coast is planned later this year. This report will provide an assessment of vulnerability for east coast barrier island communities.

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.

The USGS serves the nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.

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On the Web:

NOAA Center for Coastal Fisheries and Habitat Research Invasive Species

Come Celebrate 20 Years of Worldwide Wetlands Science on Earth Day!

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 19 Apr 2012 9:00:00 EDT

Acadiana! Come celebrate 20 Years of Worldwide Wetlands Science at the U.S. Geological Survey National Wetlands Research Center (NWRC) during INNOV8’s first Earth Day Celebration on the Research Park of the University of Louisiana in Lafayette, La.

"South-central Louisiana is the perfect location for wetland science and engineering research, and we are delighted to invite the entire community to learn more about what we do," said USGS NWRC Director, Phil Turnipseed. "There is incredibly innovative science going on in your own backyard!"

The NWRC has provided important science from their facilities at the University of Louisiana at Lafayette since 1992. The center not only focuses on the wetlands of Louisiana, but conducts studies throughout the Southeast, Texas, Mexico, and across the globe.

What: The whole family can enjoy learning about science in our own backyard at this community event. Here are just a few of the highlights:

See how the cool scientists get around! We’ll have the NWRC Science Response Vehicle, which was used to help respond to Hurricane Katrina in New Orleans; the NWRC Mobile Avian Radar Lab that tracks birds; and a variety of air and motor boats on display.
Get behind the scenes on one of the lab tours.
Check out how invasive species like nutria, island apple snails, and feral swine are studied.
Experience how scientists study Louisiana animals through the examination of furbearer pelts, bones, and bird carvings.
Be a detective! See how fast you can find your home via remote sensing imagery.
Learn more about Louisiana’s coastal wetlands, why we’re losing them, and what’s being done to save this precious North American resource!

When: Earth Day, Sunday, April 22, from 1 p.m. – 5 p.m.

Special Event Times:

Behind the scenes lab tours start at 1:00, 2:00, 3:00 and 4:00
Presentation on “Louisiana’s Coastal Wetlands: A Primer,” starts at 2:30

Where:

University Research Park,
USGS National Research Center
700 Cajundome Boulevard, Lafayette LA 70506

The USGS is just one agency participating in this exciting and educational Earth Day celebration. Kids can climb a rock wall or play in the bounce house at the Evangeline Area Council of Boy Scouts of America exhibit. Learn about coastal restoration by visiting the NOAA Estuarine Habitat and Coastal Fisheries Center next door. Louisiana’s Coastal Protection and Restoration Authority will present information about creating a sustainable coast.

Learn more about the USGS NWRC by visiting their website.

More information about INNOV8’s Earth Day Celebration is available on their website.