Earth science reaches new peaks in Denver

A robust geoscience program will draw thousands of curious minds to the Colorado Convention Center, Denver, Colorado, USA, for the 122nd Annual Meeting & Exposition of the Geological Society of America, 31 October𔃁 November 2010. More than 3700 technical presentations, in oral and poster formats, will illuminate geological and integrative science research of international, national, and regional interest.

Representatives of the media and public information officers from universities, government agencies, and research institutions, are cordially invited to attend and participate (details under III below).

To identify presentations in specific areas of interest, search topical sessions by discipline categories or sponsors using the drop-down menus at http://www.geosociety.org/meetings/2010/sessions/topical.asp, or use your browser’s “find” feature to search for keywords or convener names. Link to abstracts from each of 156 sessions from this page.

The complete technical program schedule by day is available online at http://gsa.confex.com/gsa/2010AM/finalprogram/.

I. SCIENTIFIC PROGRAM HIGHLIGHTS

Late-Breaking Session

An Update on the Deep Water Horizon Oil Spill: It was The Big One… Where is it now?
Monday, 1 November, 10:30 a.m. – noon, Colorado Convention Center, Four Seasons Ballroom 2/3.

It was the biggest oil spill in U.S. History, so what happened to the oil? The Gulf disaster has all but disappeared from the news. How much oil is still out there? Where is it? Who is looking for it? What are the long-term impacts likely to be?

Dawn Lavoie, U.S. Geological Survey Science Coordinator for the Gulf of Mexico, brings new information to bear on these and other questions as scientists and policy makers seek to understand the complexities of the situation and assess the damages. Moderator Rob Young,

Director, Program for the Study of Developed Shorelines, Western Carolina University, will give an introduction and preside during questions from the audience.

Pardee Keynote Symposia

Eight interdisciplinary, invited-speaker sessions addressing broad, fundamental issues of interest to the geoscience community comprise the Pardee Keynote Symposia, which are an essential component of the GSA meeting program each year.

Topics include:

  • The latest from NASA’s Lunar Reconnaissance Orbiter
  • Modern to ancient symbiotic associations in an interdisciplinary context of biological, geological, and geochemical earth systems evolution
  • More effective advocacy of geoscience in public policy
  • Studies of Earth’s changing near-surface mineralogy
  • Rapid environmental changes in the Cretaceous greenhouse world
  • How high-resolution LiDAR data are providing unprecedented opportunities for Earth analysis
  • The CO2 crises of ocean acidification
  • How astrobiology is highlighting key discoveries that bear on life’s origin and existence beyond Earth

See complete descriptions, schedules, speakers, photos, and session abstracts at http://www.geosociety.org/meetings/2010/sessions/pardee.htm.

Special Sessions

Mineralogy, Geochemistry, Petrology, and Volcanology (MGVP) Division Special Session

Sunday, 31 October, 1:30𔃃:30 p.m., Colorado Convention Center, Room 203

GSA’s new MGPV Division will present its first Distinguished Geologic Career Award to GSA Fellow Peter W. Lipman, who will present his 45-minute keynote talk, “Southern Rocky Mountain cookbook for the making of large ignimbrite eruptions.” An international roster of speakers will present 30-minute geologic overviews of some of Earth’s major volcanic belts, including the Chilean Andes, the Trans-Mexican Volcanic Belt, the Basin and Range, the Sierra Madre Occidental, the Taupo Volcanic Zone, the Kamchatka Peninsula, and the Columbia River Basalt Group.

View abstracts in this session at http://gsa.confex.com/gsa/2010AM/finalprogram/session_26669.htm

Cutting-Edge Geoscience Exploration: The Best of AAPG

Tuesday, 2 November, 1:30𔃃:30 p.m., Colorado Convention Center, Room 103/105

Three-dimensional seismic visuals, innovative structural geological applications, amazing application of the newest stratigraphic thinking-these concepts and more have captured presentation awards from a cadre of peers at the annual meetings of the American Association of Petroleum Geologists (AAPG). This session is designed to expose GSA attendees to the latest in applied geoscience for the advancement of resource development.

View abstracts in this session here

Structural Geology and Tectonics 30th Anniversary Symposium
Tuesday, 2 November, 1:30𔃃:30 p.m., Colorado Convention Center, Room 704/706

This special symposium is convened to honor the 30th anniversary of GSA’s Structural Geology and Tectonics Division (SG&T) Division, one of GSA’s largest.Keynote lectures will include Gary Axen of the New Mexico Institute of Mining and Technology speaking at 1:45 p.m. on “The weak-fault paradox and slip on low-angle normal faults”, and Kate Huntington of the University of Washington, speaking at 4:00 p.m. on “Plateaus to paleosols: clumped isotope thermometry of terrestrial carbonate.”

View this session at http://gsa.confex.com/gsa/2010AM/finalprogram/session_26637.htm

II. SPECIAL EVENTS

Subaru Outdoor Life Lecture: World-famous mountaineer Conrad Ankar will share his unique experiences on Mount Everest.

Monday, 1 November, 6𔃅 p.m., Colorado Convention Center
http://www.geosociety.org/meetings/2010/SubaruOutdoorLife.htm

Lunchtime Lectures: This popular series presents experts speaking on contemporary topics in a more informal “bring your own lunch” setting.
Colorado Convention Center, Room 103/105, each day from 12:15-1:15 p.m.

Sunday: Marcia Kemper McNutt, Director of the United States Geological Survey.

Monday: Timothy Killeen, Assistant Director for the Geosciences, National Science Foundation.

Tuesday: Thomas Ahlbrandt (2010 Halbouty Lecturer), Vice President of Exploration, Falcon Oil and Gas Ltd.

Wednesday: Discussion forum:
Haiti’s Catastrophic Earthquake of 12 January 2010: Lessons Learned
Moderator: Timothy Dixon, University of Miami, Rosenstiel School of Marine and Atmospheric Sciences, Professor and Director of the Space Geodesy Laboratory.
Panelists: Roger Bilham, University of Colorado; Eric Calais, Purdue University; Carol Prentice, U.S. Geological Survey.

Learn more at http://www.geosociety.org/meetings/2010/eventsLL.htm#sun.

Gold Medal Lectures: GSA President Joaquin Ruiz will chair this event for 2010 award winners to reflect on their extraordinary careers and take questions from the audience.

Sunday, 31 October, 10:00 a.m. – noon, Colorado Convention Center, Room 605

  • Penrose Medalist, Eric J. Essene (deceased 20 May 2010), University of Michigan
    John W. Valley of the University of Wisconsin will give the Penrose Gold Medal Lecture in Essene’s honor.

  • Arthur L. Day Medalist, George E. Gehrels, University of Arizona.

  • Donath Medalist (Young Scientist Award), Dana L. Royer, Wesleyan University.

III. MEDIA PARTICIPATION

Representatives of the media and public information officers from universities, government agencies, and research institutions, are cordially invited to attend and participate in technical sessions, field trips, and other special events. Eligible media personnel will receive complimentary registration and are invited to use GSA’s newsroom facilities while at the meeting.

For more information on media eligibility and registration please visit http://www.geosociety.org/meetings/2009/rMedia.htm.

The pre-registration deadline for media is Tuesday, 26 October 2010. After that date, media may register onsite in the GSA Newsroom.

GSA will operate a full-service Newsroom in the Colorado Convention Center, Room 206. Computers with internet and printer access, outgoing telephone lines, and space for interviews will be available. Continental breakfast and lunch are complimentary each day for journalists attending the meeting.

Newsroom hours of operation (Mountain Daylight Time) are:

  • Saturday, 30 October, 2:00𔃃:00 p.m.
  • Sunday through Tuesday, 31 October𔃀 November, 7:30 a.m.𔃄:00 p.m.
  • Wednesday, 3 November, 7:30 a.m.𔃀:00 p.m.

Beginning Saturday, 30 October, the newsroom telephone number for incoming calls will be
+1.303.228.8429.

First-of-its-kind study finds alarming increase in flow of water into oceans

UCI research led by Jay Famiglietti has found alarming rise in rain flows into ocean. - Credit: Daniel A. Anderson / University Communications
UCI research led by Jay Famiglietti has found alarming rise in rain flows into ocean. – Credit: Daniel A. Anderson / University Communications

Freshwater is flowing into Earth’s oceans in greater amounts every year, a team of researchers has found, thanks to more frequent and extreme storms linked to global warming. All told, 18 percent more water fed into the world’s oceans from rivers and melting polar ice sheets in 2006 than in 1994, with an average annual rise of 1.5 percent.

“That might not sound like much – 1.5 percent a year – but after a few decades, it’s huge,” said Jay Famiglietti, UC Irvine Earth system science professor and principal investigator on the study, which will be published this week in Proceedings of the National Academy of Sciences. He noted that while freshwater is essential to humans and ecosystems, the rain is falling in all the wrong places, for all the wrong reasons.

“In general, more water is good,” Famiglietti said. “But here’s the problem: Not everybody is getting more rainfall, and those who are may not need it. What we’re seeing is exactly what the Intergovernmental Panel on Climate Change predicted – that precipitation is increasing in the tropics and the Arctic Circle with heavier, more punishing storms. Meanwhile, hundreds of millions of people live in semiarid regions, and those are drying up.”

In essence, he said, the evaporation and precipitation cycle taught in grade school is accelerating dangerously because of greenhouse gas-fueled higher temperatures, triggering monsoons and hurricanes. Hotter weather above the oceans causes freshwater to evaporate faster, which leads to thicker clouds unleashing more powerful storms over land. The rainfall then travels via rivers to the sea in ever-larger amounts, and the cycle begins again.

The pioneering study, which is ongoing, employs NASA and other world-scale satellite observations rather than computer models to track total water volume each month flowing from the continents into the oceans.

“Many scientists and models have suggested that if the water cycle is intensifying because of climate change, then we should be seeing increasing river flow. Unfortunately, there is no global discharge measurement network, so we have not been able to tell,” wrote Famiglietti and lead author Tajdarul Syed of the Indian School of Mines, formerly of UCI.

“This paper uses satellite records of sea level rise, precipitation and evaporation to put together a unique 13-year record – the longest and first of its kind. The trends were all the same: increased evaporation from the ocean that led to increased precipitation on land and more flow back into the ocean.”

The researchers cautioned that although they had analyzed more than a decade of data, it was still a relatively short time frame. Natural ups and downs that appear in climate data make detecting long-term trends challenging. Further study is needed, they said, and is under way.

Geothermal mapping project reveals large, green energy source in coal country

New research produced by Southern Methodist University's Geothermal Laboratory, funded by a grant from Google.org, suggests that the temperature of the Earth beneath the state of West Virginia is significantly higher than previously estimated, and is capable of supporting commercial baseload geothermal energy production. The graphic shows subsurface West Virginia temperatures at various depths, with red points showing actual drilled temperatures. -  SMU Geothermal Laboratory
New research produced by Southern Methodist University’s Geothermal Laboratory, funded by a grant from Google.org, suggests that the temperature of the Earth beneath the state of West Virginia is significantly higher than previously estimated, and is capable of supporting commercial baseload geothermal energy production. The graphic shows subsurface West Virginia temperatures at various depths, with red points showing actual drilled temperatures. – SMU Geothermal Laboratory

New research produced by Southern Methodist University’s Geothermal Laboratory, funded by a grant from Google.org, suggests that the temperature of the Earth beneath the state of West Virginia is significantly higher than previously estimated and capable of supporting commercial baseload geothermal energy production.

Geothermal energy is the use of the Earth’s heat to produce heat and electricity. “Geothermal is an extremely reliable form of energy, and it generates power 24/7, which makes it a baseload source like coal or nuclear,” said David Blackwell, Hamilton Professor of Geophysics and Director of the SMU Geothermal Laboratory.

The SMU Geothermal Laboratory has increased its estimate of West Virginia’s geothermal generation potential to 18,890 megawatts (assuming a conservative two percent thermal recovery rate). The new estimate represents a 75 percent increase over estimates in MIT’s 2006 “The Future of Geothermal Energy” report and exceeds the state’s total current generating capacity, primarily coal based, of 16,350 megawatts.

Researchers from SMU’s Geothermal Laboratory will present a detailed report on the discovery at the 2010 Geothermal Resources Council annual meeting in Sacramento, Oct. 24-27. A summary of the report is available at http://smu.edu/smunews/geothermal/documents/west-virginia-temperatures.asp

The West Virginia discovery is the result of new detailed mapping and interpretation of temperature data derived from oil, gas, and thermal gradient wells – part of an ongoing project to update the Geothermal Map of North America that Blackwell produced with colleague Maria Richards in 2004. Temperatures below the Earth almost always increase with depth, but the rate of increase (the thermal gradient) varies due to factors such as the thermal properties of the rock formations.

“By adding 1,455 new thermal data points from oil, gas, and water wells to our geologic model of West Virginia, we’ve discovered significantly more heat than previously thought,” Blackwell said. “The existing oil and gas fields in West Virginia provide a geological guide that could help reduce uncertainties associated with geothermal exploration and also present an opportunity for co-producing geothermal electricity from hot waste fluids generated by existing oil and gas wells.”

The high temperature zones beneath West Virginia revealed by the new mapping are concentrated in the eastern portion of the state (Figure 1). Starting at depths of 4.5 km (greater than 15,000 feet), temperatures reach over 150°C (300°F), which is hot enough for commercial geothermal power production.

Traditionally, commercial geothermal energy production has depended on high temperatures in existing subsurface reservoirs to produce electricity, requiring unique geological conditions found almost exclusively in tectonically active regions of the world, such as the western United States. Newer technologies and drilling methods can be used to develop resources in wider ranges of geologic conditions. Three non-conventional geothermal resources that can be developed in areas with little or no tectonic activity or volcanism such as West Virginia are:

  • Low‐Temperature Hydrothermal – Energy is produced from areas with naturally occurring high fluid volumes at temperatures ranging from 80°C (165°F) to 150°C (300°F) using advanced binary cycle technology. Low-Temperature systems have been developed in Alaska, Oregon, and Utah.
  • Geopressure and Co-produced Fluids Geothermal – Oil and/or natural gas produced together with hot geothermal fluids drawn from the same well. Geopressure and Co-produced Fluids systems are currently operating or under development in Wyoming, North Dakota, Utah, Louisiana, Mississippi, and Texas.
  • Enhanced Geothermal Systems (EGS) – Areas with low natural rock permeability but high temperatures of more than 150°C (300°F) are “enhanced” by injecting fluid and other reservoir engineering techniques. EGS resources are typically deeper than hydrothermal and represent the largest share of total geothermal resources. EGS is being pursued globally in Germany, Australia, France, the United Kingdom, and the U.S. EGS is being tested in deep sedimentary basins similar to West Virginia’s in Germany and Australia.

“The early West Virginia research is very promising,” Blackwell said, “but we still need more information about local geological conditions to refine estimates of the magnitude, distribution, and commercial significance of their geothermal resource.”

Zachary Frone, an SMU graduate student researching the area said, “More detailed research on subsurface characteristics like depth, fluids, structure and rock properties will help determine the best methods for harnessing geothermal energy in West Virginia.” The next step in evaluating the resource will be to locate specific target sites for focused investigations to validate the information used to calculate the geothermal energy potential in this study.

The team’s work may also shed light on other similar geothermal resources. “We now know that two zones of Appalachian age structures are hot – West Virginia and a large zone covering the intersection of Texas, Arkansas, and Louisiana known as the Ouachita Mountain region,” said Blackwell. “Right now we don’t have the data to fill in the area in between,” Blackwell continued, “but it’s possible we could see similar results over an even larger area.”

Blackwell thinks the finding opens exciting possibilities for the region. “The proximity of West Virginia’s large geothermal resource to east coast population centers has the potential to enhance U.S. energy security, reduce CO2 emissions, and develop high paying clean energy jobs in West Virginia,” he said.

SMU’s Geothermal Laboratory conducted this research through funding provided by a Google.org’s initiative dedicated to using the power of information and innovation to advance breakthrough technologies in clean energy.

Ancient Colorado river flowed backwards

Geologists have found evidence that some 55 million years ago a river as big as the modern Colorado flowed through Arizona into Utah in the opposite direction from the present-day river. Writing in the October issue of the journal Geology, they have named this ancient northeastward-flowing river the California River, after its inferred source in the Mojave region of southern California.
Geologists have found evidence that some 55 million years ago a river as big as the modern Colorado flowed through Arizona into Utah in the opposite direction from the present-day river. Writing in the October issue of the journal Geology, they have named this ancient northeastward-flowing river the California River, after its inferred source in the Mojave region of southern California.

Geologists have found evidence that some 55 million years ago a river as big as the modern Colorado flowed through Arizona into Utah in the opposite direction from the present-day river. Writing in the October issue of the journal Geology, they have named this ancient northeastward-flowing river the California River, after its inferred source in the Mojave region of southern California.

Lead author Steven Davis, a post-doctoral researcher in the Department of Global Ecology at the Carnegie Institution, and his colleagues* discovered the ancient river system by comparing sedimentary deposits in Utah and southwest Arizona. By analyzing the uranium and lead isotopes in sand grains made of the mineral zircon, the researchers were able to determine that the sand at both localities came from the same source — igneous bedrock in the Mojave region of southern California.

The river deposits in Utah, called the Colton Formation by geologists, formed a delta where the river emptied into a large lake. They are more than 400 miles (700 kilometers) to the northeast of their source in California. “The river was on a very similar scale to the modern Colorado-Green River system,” says Davis, “but it flowed in the opposite direction.” The modern Colorado River’s headwaters are in the Rocky Mountains, flowing southeast to the river’s mouth in the Gulf of California.

The deposits of the Colton Formation are approximately 55 million years old. Recently, other researchers have speculated that rivers older than the Colorado River may have carved an ancestral or “proto” Grand Canyon around this time, long before Colorado began eroding the present canyon less than 20 million years ago. But Davis sees no evidence of this. “The Grand Canyon would have been on the river’s route as it flowed from the Mojave to Utah, he says. “It stands to reason that if there was major erosion of a canyon going on we would see lots of zircon grains from that area, but we don’t.”

The mighty California River likely met its end as the Rocky Mountains rose and the northern Colorado Plateau tilted, reversing the slope of the land surface and the direction of the river’s flow to create the present Colorado-Green River system. Davis and his colleagues have not determined precisely when the change occurred, however. “The river could have persisted for as long as 20 million years before the topography shifted enough to reverse its flow,” he says.

University of Nevada, Reno’s earthquake lab gets $12 million from Commerce Department

The University of Nevada, Reno recently tested a 110-foot 200 ton concrete bridge in its large-structures earthquake engineering lab, which just received $12.2 million from the US Department of Commerce in a competitive grant process to more than double the size of the facility. -  Photo by Mike Wolterbeek, University of Nevada, Reno.
The University of Nevada, Reno recently tested a 110-foot 200 ton concrete bridge in its large-structures earthquake engineering lab, which just received $12.2 million from the US Department of Commerce in a competitive grant process to more than double the size of the facility. – Photo by Mike Wolterbeek, University of Nevada, Reno.

The University of Nevada, Reno has been awarded $12.2 million from the U.S. Department of Commerce’s National Institute of Standards and Technology, it was announced Wednesday. This will fund the major portion of an expansion of the world-renowned earthquake engineering lab where, for the past 25 years, researchers have conducted successful experiments of building and testing large-scale structures and bridges to advance seismic safety.

The expanded facility will house the largest and most versatile earthquake simulation laboratory in the United States. The $18 million project also received funds from the Department of Energy last year to finance the initial phase of construction of the 23,000-square-foot project, scheduled to begin in October. When completed, the combined area of the new and existing facilities will exceed 30,000 square feet.

The University was one of only five institutions – from more than 100 applicants nationwide – that received grant money from the NIST Construction Grants Program. The project will create short-term construction jobs and have a positive long-term employment and economic impact through other agency and private industry projects.

“Strengthening research and development in the United States is critical to our ability to create jobs and remain competitive,” U.S. Commerce Secretary Gary Locke said. “These construction grants will help the U.S. produce world-leading research in science and technology that will advance our economic growth and international competitiveness.”

“This expansion is a major accomplishment that will make us more competitive and productive,” Manos Maragakis, dean of the College of Engineering, said. “Our facility will be unique worldwide and, combined with the excellence of our faculty and students, will allow us to have even greater contributions to the seismic safety of our state, the nation and the world.

“A good part of why we received this funding is because of the high quality work we do and the high-caliber faculty. The competitive nature of this award adds significantly to the importance and prestige of this accomplishment.”

Buckle, director of the Large-Scale Structures Lab, said the expanded facility will house the University’s four large 14-by-14-foot, 50-ton-capacity shake tables that are capable of replicating, through computer software and massive hydraulically-operated actuators, any recorded earthquake.

“The new building configuration will allow for a fifth shake table and more versatile use of the equipment while freeing up space for additional experiments,” Buckle said. “We have a backlog now, a long list of projects of people and agencies who want to use the lab. For example, our next big project is a 145-foot, curved, 130-ton bridge project that takes up every bit of current space, door-to-door and wall-to-wall.”

The greatly expanded research space will allow for additional experiment configurations for large-scale models of buildings, and experiments that are not possible in the existing facility, such as simulating the effect of seismic waves propagating through layers of soil under foundations.

“This will be a quantum jump in the range and complexity of experiments that can be undertaken in both new and existing laboratories, with advances in state-of-the-art earthquake engineering that are not currently possible,” Buckle said. “Safer buildings, bridges and more resilient communities will be the end result.”

The University’s Center for Civil Engineering Earthquake Research carries out research for federal and state agencies, the private sector and non-profit organizations. In addition to highway bridges, the Center’s current research efforts include the study of non-structural components in buildings and alternative building materials.

“The earthquake research done here at the University and in this laboratory has discovered new knowledge, stretched intellectual boundaries and at the same time provided useful research,” University President Milt Glick said. “So when there’s a bridge problem in San Francisco, they call upon our faculty to help them solve the design problem. And, when they want to design a safer building, where do they come? They come here.”

The facility supports itself financially. In the past 10 years, major research grants and contracts acquired by the Center for Civil Engineering Earthquake Research totaled $38.5 million.

“With the expansion we can accommodate more students and their projects and more of the local construction industry will be able to use it, bringing in multi-thousand dollar specimens,” Buckle said.

Almost 20 academic, research and administrative faculty, scientists and technicians are affiliated with the Center for Civil Engineering Earthquake Research and the earthquake simulation lab. About 30 doctoral and masters students are engaged in research projects under the Center’s umbrella. Total research funding in 2009 was about $3.5 million. In its 25-year history the Center has published more than 160 technical reports that describe the results of these activities.

The University facility is managed as a national shared-use National Earthquake Engineering Simulation site created and funded by the National Science Foundation in 2004 to provide new earthquake-engineering research and testing capabilities for large structural systems. This NEES equipment site is connected to the NEES Consortium of 14 other universities.

“UNR’s earthquake research center is among the best in the nation, providing real-time data that is vital to maintaining safe roadways, bridges and buildings that can endure Nevada’s frequent seismic activity,” said Nevada Sen. Harry Reid. “Thanks to this funding, UNR will have the facility and resources needed to build on the quality work they already perform and help keep Nevadans safe.”

The project is expected to be complete in 2013.

Ocean conditions likely to reduce Colorado River flows during this winter’s drought

A remote stretch of the Colorado River from the Escalante Route in the Grand Canyon
A remote stretch of the Colorado River from the Escalante Route in the Grand Canyon

The convergence in the coming year of three cyclical conditions affecting ocean temperatures and weather is likely to create unprecedented challenges for states that depend on water from the Colorado River, a new UCLA study suggests.

“If I were concocting a recipe for a perfect drought, this would be it,” said Glen MacDonald, co-author of the study and director of UCLA’s Institute of the Environment and Sustainability.

Along with a former graduate student, MacDonald has found that the combination of La Niña with two less commonly known ocean conditions – the Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation – tends to result in drought in the upper reaches of the Colorado River. The ocean conditions have been known to diminish precipitation in the Southwest but, examined separately, have proven to be poor indicators of drought conditions in the upper reaches of the river.

“It’s the combination that’s key,” said lead author Abbie Tingstad, who conducted the research as a graduate student in geography at UCLA. She is now an associate physical scientist at the RAND Corp.

The convergence of these patterns in the Pacific and Atlantic oceans may well drive water levels in the Lake Mead reservoir below a critical threshold and could potentially result in reduced water allocations for Arizona and Nevada, the researchers say.

Essentially all of the Colorado River water used by Southern California passes through the reservoir, which is the largest in the nation. Fed primarily by snowpack melt from its upper reaches, the river is Southern California’s chief source of water.

“Declines in water availability of this magnitude during the coming winter could be devastating for states that depend on the Colorado River for their water,” Tingstad said.

The study appears in the October issue of the Journal of the American Water Resources Association.

By studying ancient tree rings, Tingstad and MacDonald were able to reconstruct river flow and winter snowpack levels going back several hundred to almost 1,000 years for a mountainous region of northeastern Utah. Responsible for 10 percent to 15 percent of the flow in the river, the Uinta Mountains region has a climate representative of the upper Colorado River basin, the researchers say, so conditions experienced there are similar to those that occurred elsewhere in the upper basin.

The tree rings came from a combination of dead and living pinyon pines that grow on extremely dry slopes in the Uintas. Described by Tingstad as “listening posts for climate variability and drought,” the trees produce annual rings that are so sensitive to water stress that the researchers can track changes in annual precipitation on the order of an inch by studying them under microscopes.

Tingstad and MacDonald then compared their records with existing records for La Niña, the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). During a La Niña episode, the sea-surface temperature across the Pacific Ocean at the equator plummets by as much 18 degrees Fahrenheit, resulting in drops in precipitation rates of as much as 50 percent across the southwestern and southeastern United States for between five and 18 months.

The PDO is a pattern of climate variability with longer-term shifts that last between 20 and 30 years and also affect weather. A negative PDO is characterized by cooler sea-surface temperatures off the Pacific Coast of North America that can result in below-average precipitation in the southwestern U.S. The effect can be thought of as an extended La Niña event.

Each phase of the AMO can last for more than 60 years and is characterized by temperature changes in the North Atlantic Ocean. In its positive phase, the AMO has little impact on California weather if it occurs in absence of a negative PDO. But the positive AMO has been linked to past occurrence of major droughts in the Midwest and the Southwest, including the Dust Bowl of the 1930s.

“It’s three different things working on different times scales,” MacDonald said. “You may not get them to line up that frequently.”

Tingstad and MacDonald found a “striking and significant propensity” for droughts in northeastern Utah when cool sea-surface temperatures in the Pacific associated with La Niña
and the negative phase of the PDO were coupled with warm temperatures in the North Atlantic linked to the positive phase of the AMO. During such episodes, snowpack declined
on average between 9 percent and 10 percent, and river discharge decreased on average by 18 percent.

The three conditions last converged at least five times between 1945 and 1965, a period that was characterized by generally depressed but variable flows in the river, they said.

The findings are troublesome because not only are all three conditions predicted for 2010󈝷, but they are expected to be particularly strong, the researchers say. The coming year’s La Niña and AMO are at this point supposed to be the strongest in 10 years, and a strong negative PDO is also building.

The convergence increases the likelihood that Lake Mead, already diminished by 11 years of drought, will fall below 1,075 feet above sea level – a threshold that can result in the reduction of water allocations in Nevada and Arizona, the researchers say. Under a series of agreements among seven U.S. states along the Colorado River and Mexico, California has first rights to the water, so it would not face the same restrictions. Water levels at Lake Mead currently stand just nine feet from the critical threshold, at 1,084 feet above sea level.

“We’re looking at a situation that could pit us against our neighbors,” said MacDonald, who is also a UCLA professor of geography. “We’ve never had to face such a severe decline in Lake Mead and resulting reductions in Colorado River allocations before.”

Under the agreements, federal authorities have the power, once Lake Mead falls to 1,075 feet, to request reductions of approximately 11.4 percent on Arizona and 4.3 percent on Nevada – cuts of 320,000 and 13,000 acre feet, respectively.

“That means these states might have to find many millions of gallons to make up what seem like relatively small-percentage reductions, and they have to do so at a time when they are already in a drought of considerable duration,” MacDonald said. “That’s going to be a real problem.”

Scientists first to map offshore San Andreas Fault and associated ecosystems

This mulitbeam sonar image shows the San Andreas Fault cutting through the head of Noyo Canyon, offshore approximately 12 miles northwest of Fort Bragg, Calif. Image courtesy of San Andreas Fault 2010 Expedition, NOAA-OER
This mulitbeam sonar image shows the San Andreas Fault cutting through the head of Noyo Canyon, offshore approximately 12 miles northwest of Fort Bragg, Calif. Image courtesy of San Andreas Fault 2010 Expedition, NOAA-OER

For the first time, scientists are using advanced technology and an innovative vessel to study, image, and map the unexplored offshore Northern San Andreas Fault from north of San Francisco to its termination at the junction of three tectonic plates off Mendocino, Calif.

The team includes scientists from NOAA’s National Marine Fisheries Service, Oregon State University, the California Seafloor Mapping Program, the U.S. Geological Survey and Woods Hole Oceanographic Institution. The expedition which concludes Sunday is sponsored by NOAA’s Office of Ocean Exploration and Research.

While the fault on land is obscured by erosion, vegetation and urbanization in many places, scientists expect the subsea portion of the fault to include deep rifts and high walls, along with areas supporting animal life. The expedition team is using high-resolution sonar mapping, subsurface seismic data and imaging with digital cameras for the first-ever three-dimensional bathymetric-structural map that will model the undersea Northern San Andreas Fault and its structure. Little is known about the offshore fault due to perennial bad weather that has limited scientific investigations.

“By relating this 3-D model with ongoing studies of the ancient record of seismic activity in this volatile area, scientists may better understand past earthquakes – in part because fault exposure on land is poor, and the sedimentary record of the northern California offshore fault indicates a rich history of past earthquakes,” said Chris Goldfinger, co-principal investigator and marine geologist and geophysicist at Oregon State University in Corvallis, Ore. “The model will also benefit geodetic studies of the buildup of energy to help better understand the potential for earthquakes.”

More than a century after the 1906 Great San Francisco Earthquake, the science team is also exploring the fault for lessons associated with the intertwined relationships between major earthquakes and biological diversity. Evidence shows that active fluid and gas venting along fast-moving tectonic systems, such as the San Andreas Fault, create and recreate productive, unique and unexplored ecosystems.

“This is a tectonically and chemically active area,” said Waldo Wakefield, co-principal investigator and a research fisheries biologist at NOAA’s Northwest Fisheries Science Center in Newport, Ore. “I am looking for abrupt topographic features as well as vents or seeps that support chemosynthetic life – life that extracts its energy needs from dissolved gasses in the water. I’m also looking at sonar maps of the water column and images of the seafloor for communities of life.”

A variety of sensors and systems are being used to help locate marine life including a NOAA autonomous underwater vehicle (AUV) named ‘Lucille.’ Elizabeth Clarke, a NOAA fisheries scientist, is coordinating Lucille’s operations and obtaining photographic information about fauna associated with the fault. The AUV and its sensors can dive to nearly one mile (1,500 meters), but depths associated with this expedition will range between approximately 230 to 1100 feet (70 to 350 meters).

Early in the expedition, scientists collected bathymetric and subsurface seismic reflection data to guide them to specific areas of interest for follow-on and more detailed operations. The AUV’s high-definition cameras are obtaining multiple images to be stitched into “photo mosaics” showing detailed fault structure and animal life.

The first part of the expedition is operating from Research Vessel Derek M. Baylis, a “green” research vessel primarily powered by sail and owned by Sealife Conservation, a nonprofit organization. The expedition will track the carbon footprint of the 65-foot energy efficient Baylis and compare results to conventional vessels.

AUV operations are being conducted aboard the Research Vessel Pacific Storm, operated by Oregon State University’s Marine Mammal Institute. The ship and AUV team joined the expedition offshore of Fort Bragg on Sept. 25.

As the expedition progresses, NOAA’s Ocean Explorer website features maps and images of the fault and associated ecosystems, logs from scientists at sea, and lesson plans that align with National Science Education Standards at three grade levels.

Simple approach could clean up oil remaining from Exxon Valdez spill

Traces of crude oil that linger on the shores of Alaska’s Prince William Sound after the Exxon Valdez oil spill remain highly biodegradable, despite almost 20 years of weathering and decomposition, scientists are reporting in a new study. Their findings, which appear in ACS’ semi-monthly journal Environmental Science & Technology, suggest a simple approach for further cleaning up remaining traces of the Exxon Valdez spill – the largest in U.S. waters until the 2010 Deepwater Horizon episode.

Albert D. Venosa and colleagues note that bacteria, evaporation, sunlight, and other items in Mother’s Nature’s clean-up kit work together to break down the oil and make it disappear. Scientists have known for years that adding nitrogen and phosphorus fertilizer to oil-contaminated soil can speed the growth of bacteria that decompose, or biodegrade, oil. But it has been uncertain whether oil that has lingered in the environment for almost 20 years still is biodegradable, leaving questions on whether further clean-up efforts might be worthwhile.

The scientists collected oil-contaminated soil from different beaches in Prince William Sound and treated the samples with phosphorus and nitrogen fertilizer in the presence of excess oxygen from the air. Oil in the fertilized samples biodegraded up to twice as fast as oil in the unfertilized control samples, but significant biodegradation occurred even in the unfertilized controls. The results showed that oxygen supply was the major bottleneck, or limiting factor, in the field that prevented further decomposition of the oil. The scientists used data from the research to postulate a simple treatment scheme that would involve applying simple nitrate salts to possibly break down the natural organic matter in the sediment. That would cause an increase in sediment porosity that would allow dissolved oxygen in seawater to penetrate to the oiled zone and create oxygen-rich conditions that might stimulate more rapid biodegradation.