Updated: 3 min 38 sec ago
Summary: Nearly forgotten research from decades ago complicates the task of quantifying earthquake hazards in the Pacific Northwest, according to a new report from scientists at the U.S. Geological Survey, the University of Washington, and other universities
SEATTLE, Wash. — Nearly forgotten research from decades ago complicates the task of quantifying earthquake hazards in the Pacific Northwest, according to a new report from scientists at the U.S. Geological Survey, the University of Washington, and other universities.
The report focuses on the Cascadia subduction zone—a giant active fault that slants eastward beneath the Pacific coast of southern British Columbia, Washington, Oregon, and northern California. Geologic studies in the past three decades have provided increasingly specific estimates of Cascadia earthquake sizes and repeat times. The estimates affect public safety through seismic provisions in building design and tsunami limits on evacuation maps.
The new report does not question whether the Cascadia subduction zone repeatedly produces enormous earthquakes. What the report asks instead is how much geologists can say, with confidence, about the history of those earthquake going back thousands of years. How big was each of the earthquakes? Did they occur twice as often along one part of the subduction zone as another? The report concludes that extracting such details from deep-sea sediments is more complicated than was previously thought.
The report reappraises sediment cores that were collected near the foot of the continental slope offshore Washington. A subset of cores from this area underpins influential estimates of Cascadia earthquake size and recurrence that were published in 2012. The new report points to confounding evidence from a much larger suite of cores that were collected and first analyzed by University of Washington and Oregon State University scientists in the late 1960s and early 1970s.
Those Nixon-era cores were the work of researchers unconcerned with earthquakes. Plate tectonics was then such a new idea that scientists were just beginning to recognize the Cascadia subduction zone as a tectonic plate boundary. The sediment cores were collected to learn about turbidites—beds of sand and mud laid down by bottom-hugging, sediment-driven currents that infrequently emerged from submarine canyons onto the deep ocean floor. Not until a 1990 report would turbidites be reinterpreted as clues to Cascadia earthquake history.
“Rethinking turbidite paleoseismology along the Cascadia subduction zone” is freely available online in Geology, a leading Earth-science journal. The authors are Brian Atwater (U.S. Geological Survey), Bobb Carson (Lehigh University), Gary Griggs (University of California Santa Cruz), and Paul Johnson and Marie Salmi (University of Washington).
Summary: Nesting loggerhead sea turtles in the northern Gulf of Mexico feed among areas that were oiled by the 2010 Deepwater Horizon spill and where human activities occur, several of which are known to pose threats to sea turtles, a new U.S Geological study showed
DAVIE, Fla.— Nesting loggerhead sea turtles in the northern Gulf of Mexico feed among areas that were oiled by the 2010 Deepwater Horizon spill and where human activities occur, several of which are known to pose threats to sea turtles, a new U.S Geological study showed.
The feeding areas for 10 turtles overlapped with an area that experienced surface oiling during the 2010 Deepwater Horizon oil spill. These sites, and others, also overlapped with areas trawled by commercial fishing operations and used for oil and gas extraction.
The study, which is the largest to date on Northern Gulf loggerheads, examined 59 nesting females, which scientists believe could be 15 percent of the breeding females in the Northern Gulf of Mexico—a small and declining subpopulation of loggerheads that is federally classified as threatened.
“With such a large sample of the nesting females, we’re finally getting the big picture of when, where and how females that nest in the northern Gulf of Mexico rely on off-shore waters to survive. This information is critical for halting and reversing their declines,” said USGS research ecologist Kristen Hart, the lead author of the study.
The study began in the wake of the Deepwater Horizon oil spill as a means to better understand how sea turtles used habitat in the Northern Gulf of Mexico by analyzing the movements of turtles tagged between 2010 and 2013.
All of the turtles tracked in the study remained in the Gulf of Mexico to feed, and a third remained in the northern part of the Gulf. This differs from reports in other parts of the world, where some loggerheads have been shown to migrate across ocean basins after nesting.
“These results show how important the Gulf of Mexico is to this group of loggerheads – they stay here throughout the year, not just during the nesting season,” said USGS research biologist Meg Lamont, a co-author on the study.
The study also revealed specific parts of the Gulf where females feed and spend most of their time. It is believed that an individual turtle will return to these specific feeding areas throughout her life, a trait scientists call “foraging site fidelity.”
“With this study, we essentially discovered their homes – the waters where these loggerheads spend most of the year,” Lamont said. “People think of nesting beaches as their homes, but they don’t really spend much time there. They only migrate to the nesting beaches to lay eggs. The rest of their adult life is spent foraging at sea.”
The next step for USGS scientists Hart and Lamont is to track these nesting Gulf loggerheads long enough to test whether they do indeed re-visit the same feeding areas throughout their life, as they suspect. This would help pinpoint important feeding sites of long-term and high traffic use – in essence, their home ranges.
“Locating long-term feeding areas will really open up new possibilities for the conservation and management of these amazing creatures,” said Hart.
The study, “Migration, foraging, and residency patterns for Northern Gulf of Mexico loggerheads: Implications of local threats and international movements” was recently published in the journal PLOS ONE.
Summary: Since August 2013, all 50 states have been available for editing with the USGS The National Map Corps (TNMCorps) volunteered geographic information project. Starting this month, TNMCorps is pleased to add the United States Virgin Islands to that list The U.S. Virgin Islands are now available for structure updates with The National Map Corps crowd-sourcing volunteers
Since August 2013, all 50 states have been available for editing with the USGS The National Map Corps (TNMCorps) volunteered geographic information project. Starting this month, TNMCorps is pleased to add the United States Virgin Islands to that list.
Using crowd-sourcing techniques, TNMCorps encourages citizen volunteers to collect data about manmade structures in an effort to provide accurate and authoritative spatial map data for the USGS National Geospatial Program’s web-based The National Map.
Through an online map editor, volunteers use aerial images and other resources to improve structures data by adding new features, removing obsolete points, and correcting existing data. Points available to edit include schools, hospitals, post offices, police stations and other important public buildings. Volunteers may find editing structures in the U.S. Virgin Islands quite challenging, as some source data points shown in the map editor may be out of date, and some structure types are missing entirely.
One of many younger volunteers has found that contributing to The National Map Corps has been a rewarding summer activity. “I’ve only been working for a month and already I’ve discovered interesting facts, like where Sacagawea is buried, and all of the unique names for places around the country,” said user “crazeyme,” who is also one of the top producing participants.
To recognize our volunteers, TNMCorps has instituted a recognition program that awards "virtual" badges" based on the number of points edited. Badges consist of a series of antique surveying instruments ranging from the Surveyor's Chain (25 – 50 points) to the Theodolite Assemblage (2000+ points). Additionally, volunteers are publically recognized (with user permission) via Twitter, Google+, and Facebook.
Volunteers only need access to a computer and the Internet to participate. The National Map Corps’ website explains how volunteers can edit any area, regardless of their familiarity with the selected structures. Registration is simple and requires only an email address and self-selected username.
Participants make a significant addition to the USGS's ability to provide accurate information to the public. Data collected by volunteers become part of The National Map structures dataset which is available to users free of charge.
See for yourself how much fun participating can be. Go to The National Map Corps and give it a try.Screen shot of The National Map Corps editor webpage showing the capitol city of Charlotte Amalie on St. Thomas, St. Thomas. Within this image lies the governmental center, public schools, and more– which is why The National Map Corps needs your help! (high resolution image 3.3 MB) Badges awarded for submitting edits, shown in from first to last: Order of the Surveyor’s Chain (25-49), Society of the Steel Tape 50-99), Pedometer Posse (100-199), Surveyor’s Compass (200-499), Stadia Board Society (500-999), Alidade Alliance (1000-1999), and Theodolite Assemblage (2000+). New awards for volunteers exceeding 2,000 points are under review. (high resolution image 114.7KB)
Summary: Streamflow in the eastern portions of the Missouri River watershed has increased over the past 52 years, whereas other parts have seen downward trends
Reporters: Video footage of an interview with lead USGS scientist Parker Norton is available online.
Streamflow in the eastern portions of the Missouri River watershed has increased over the past 52 years, whereas other parts have seen downward trends.
U.S. Geological Survey scientists recently studied data from 227 streamgages in the Missouri River watershed that had continuous records for 1960 through 2011. The scientists found that almost half of the streamgages showed either an upward or downward trend in mean annual flow since 1960, while the rest showed no trend.
The study is relevant on a large scale because the Missouri River is the longest river in the United States, with a watershed that includes mountainous to prairie topography in all or parts of 10 states and small parts of Alberta and Saskatchewan in Canada.
“The Missouri River and its tributaries are valuable for agriculture, energy, recreation and municipal water supplies,” said USGS hydrologist Parker Norton. “Understanding streamflow throughout the watershed can help guide management of these critical water resources.”
According to the study, streamflow has increased in the eastern part of the watershed, including eastern North Dakota, eastern South Dakota, western Iowa and eastern Nebraska. Annual flows have decreased in the western headwaters area of the Missouri River in Montana and Wyoming, and in the southern part of the basin associated with the Kansas River watershed.
Climate changes that affect how and where moisture is delivered to the continent may be causing some of these trends in the Missouri River Basin. Although the USGS scientists did not conduct a complete analysis of the causes, they noted that increased streamflow over broad regions occurred despite the increasing use of water. Decreased streamflow in some areas could also be related to climate change factors, or to groundwater pumping.
The USGS report can be accessed online.
For more than 125 years, the USGS has monitored flow in selected streams and rivers across the United States. The information is routinely used for water supply and management, monitoring floods and droughts, bridge and road design, determination of flood risk and for many recreational activities.
Access current flood and high flow conditions across the country by visiting the USGS WaterWatch website. Receive instant, customized updates about water conditions in your area via text message or email by signing up for USGS WaterAlert.
Summary: Urban areas in the Southeastern United States will double in size by 2060 unless there are significant changes to land development, according to a new study by the Department of Interior’s Southeast Climate Science Center and North Carolina State University
RALEIGH, N.C.—Urban areas in the Southeastern United States will double in size by 2060 unless there are significant changes to land development, according to a new study by the Department of Interior’s Southeast Climate Science Center and North Carolina State University.
The predicted growth would come at the expense of agricultural and forest lands, creating an urban “megalopolis” stretching from Raleigh to Atlanta, which also raises a number of ecological concerns.
“If we continue to develop urban areas in the Southeast the way we have for the past 60 years, we can expect natural areas will become increasingly fragmented,” said Adam Terando, a research ecologist with the U.S. Geological Survey, adjunct assistant professor at NC State, and lead author of the study. “We could be looking at a seamless corridor of urban development running from Raleigh to Atlanta, and possibly as far as Birmingham, within the next 50 years.”
To understand how urban and natural environments could change, the researchers used NC State’s High Performance Computing services to simulate urban development between now and 2060 across the Southeastern United States.
Among the expected impacts of such expansive urban growth, the fragmentation of natural areas would significantly limit the mobility of wildlife, making it more difficult for them to find mates, raise young, find food and respond to environmental changes.
“This, in turn, increases the likelihood that we’ll see more conflicts between people and wildlife, such as the increasing interactions with bears we’re seeing in our suburban areas,” Terando said.
An increase in urbanization would also make urban heat islands—the warming of cities due to human activities and development—more common, favoring species that can take advantage of the hotter conditions in cities. For example, previous studies have found that insect pests – such as scale insects – thrive in urban environments.
“Unless we change course, over the next 50 years urbanization will have a more pronounced ecological impact in many non-coastal areas of the Southeast than climate change, said Jennifer Costanza, a research associate at NC State and a co-author of the study. “It’s impossible to predict precisely what the specific ecological outcomes would be, but so far, the projections are not good in terms of biodiversity and ecosystem health.”
This research emphasizes how decision makers involved in community planning will need a well-thought out strategy for future development, Costanza said.
“Given that urbanization poses significant challenges to this region, decision makers will need to begin serious, long-term discussions about economic development, ecological impacts and the value of non-urban spaces,” she added.
The paper, “The southern megalopolis: using the past to predict the future of urban sprawl in the Southeast U.S.,” is published in PLOS ONE. The paper was co-authored by Adam Terando, Alexa McKerrow and Jaime A. Collazo of the USGS; and Jennifer Costanza, Curtis Belyea and Rob Dunn of NC State. The work was supported by the DOI Southeast Climate Science Center based at NC State. The center provides scientific information to help natural resource managers respond effectively to climate change.
Summary: Due to climate change, some communities in rural Alaska and the Yukon Territory of Canada may face a future with fewer caribou according to new research published by the U.S. Geological Survey and the University of Alaska, Fairbanks in the recent issue of PLoS ONE
Caribou from the Central Arctic herd along the Sagavanirktok River in northern Alaska. (High resolution image)
ANCHORAGE, Alaska — Due to climate change, some communities in rural Alaska and the Yukon Territory of Canada may face a future with fewer caribou according to new research published by the U.S. Geological Survey and the University of Alaska, Fairbanks in the recent issue of PLoS ONE. Scientists examined the future effects of fires on winter habitats of caribou herds and determined that wildfires will reduce the amount of winter habitat for caribou, thus caribou may need to shift their wintering grounds
Warming temperatures will increase the flammability of lichen-producing boreal forests, which are important winter habitat for caribou herds. Caribou serve as nutritional as well as cultural sustenance for certain communities. Caribou avoid burned areas in winter and the changes in their distribution can persist across multiple generations of hunters. Those who rely on caribou in fire-prone areas may therefore have fewer available as climate change increases the number and sizes of fires in the boreal forests.
“We project that the Porcupine caribou herd will lose 21% of winter habitat to fire by the end of this century, with the majority of this loss driven by increased flammability in spruce forests in the Yukon," said Dr. Dave Gustine, a Research Wildlife Biologist with the USGS and lead author of the study.
The study examines how increasing temperatures will influence flammability of boreal forest areas used by the Central Arctic and Porcupine caribou herds during winter. Understanding possible changes to forest flammability allows forecasting of future winter distributions of caribou that will impact subsistence harvest and land, wildlife and fire management programs.
Climate change is global in scope and scale; however, its impacts are sometimes most visible in remote locations of the planet. Like climate change itself, migratory animals such as caribou do not recognize international geo-political borders and the research needed to study the relationship between climate change and animals crosses many countries.
The potential changes in caribou distribution will affect communities that have a cultural and nutritional reliance on caribou. Arctic Village, Alaska and Old Crow Yukon Territory, are within the traditional boreal forest winter range of the Porcupine herd, while hunters from the Alaskan villages of Fort Yukon, Venetie and Chalkyitsik, travel north each year to harvest animals from this herd.
“Fires were less numerous and smaller in tundra habitats compared to spruce habitats and given the more likely climate trajectory, we projected that the Porcupine caribou herd, which winters primarily in the boreal forest, could be expected to experience a greater reduction in lichen-producing winter habitats than the Central Arctic herd that wintered primarily in the arctic tundra,” said Dr. Todd Brinkman a co-author of the study and member of the Scenarios Network for Alaska and Arctic Planning at the University of Alaska, Fairbanks.
Future work by the USGS and collaborators will examine how fire-driven changes to winter habitat and temperature-driven changes to spring and summer forages will influence the habitats of caribou across the Alaskan Arctic.
This work is part of the USGS Changing Arctic Ecosystems Initiative.Simulation domain and winter ranges of the Central Arctic and Porcupine caribou herds, Alaska and Yukon. (High resolution image)
Summary: Insecticides similar to nicotine, known as neonicotinoids, were found commonly in streams throughout the Midwest, according to a new USGS study
Insecticides similar to nicotine, known as neonicotinoids, were found commonly in streams throughout the Midwest, according to a new USGS study. This is the first broad-scale investigation of neonicotinoid insecticides in the Midwestern United States and one of the first conducted within the United States.
Effective in killing a broad range of insect pests, use of neonicotinoid insecticides has dramatically increased over the last decade across the United States, particularly in the Midwest. The use of clothianidin, one of the chemicals studied, on corn in Iowa alone has almost doubled between 2011 and 2013.
“Neonicotinoid insecticides are receiving increased attention by scientists as we explore the possible links between pesticides, nutrition, infectious disease, and other stress factors in the environment possibly associated with honeybee dieoffs.” said USGS scientist Kathryn Kuivila, the research team leader.
Neonicotinoid insecticides dissolve easily in water, but do not break down quickly in the environment. This means they are likely to be transported away in runoff from the fields where they were first applied to nearby surface water and groundwater bodies.
In all, nine rivers and streams, including the Mississippi and Missouri Rivers, were included in the study. The rivers studied drain most of Iowa, and parts of Minnesota, Montana, Nebraska, North Dakota, South Dakota, and Wisconsin. These states have the highest use of neonicotinoid insecticides in the Nation, and the chemicals were found in all nine rivers and streams.
Of the three most often found chemicals, clothianidin was the most commonly detected, showing up in 75 percent of the sites and at the highest concentration. Thiamethoxam was found at 47 percent of the sites, and imidacloprid was found at 23 percent. Two, acetamiprid and dinotefuran, were only found once, and the sixth, thiacloprid, was never detected.
Instead of being sprayed on growing or full-grown crops, neonicotinoids can be applied to the seed before planting. The use of treated seeds in the United States has increased to the point where most corn and soybeans planted in the United States have a seed treatment (i.e., coating), many of which include neonicotinoid insecticides.
“We noticed higher levels of these insecticides after rain storms during crop planting, which is similar to the spring flushing of herbicides that has been documented in Midwestern U.S. rivers and streams,” said USGS scientist Michelle Hladik, the report’s lead author. “In fact, the insecticides also were detected prior to their first use during the growing season, which indicates that they can persist from applications in prior years.”
One of the chemicals, imidacloprid, is known to be toxic to aquatic organisms at 10-100 nanograms per liter if the aquatic organisms are exposed to it for an extended period of time. Clothianidin and thiamethoxam behave similarly to imidacloprid, and are therefore anticipated to have similar effect levels. Maximum concentrations of clothianidin, thiamethoxam and imidacloprid measured in this study were 257, 185, and 42.7 nanograms per liter, respectively.
The U.S. Environmental Protection Agency has classified all detected neonicotinoids as not likely to be carcinogenic to humans.
The paper, “Widespread occurrence of neonicotinoid insecticides in streams in a high corn and soybean producing region, USA” and has been published in Environmental Pollution. Learn more about the study and the long-term USGS effort to gather information on the environmental occurrence of new pesticides in different geographic, climatic, and use settings here. To learn more about USGS environmental health science, please visit the USGS Environmental Health website and sign up for our GeoHealth Newsletter.Locations of sites in Iowa sampled for neonicotinoids in 2013. Watersheds for the Mississippi River and Missouri River sites are shown in the inset.