bluuebunny/crossref_metadata_2025 huggingface dataset:
Database of geomagnetic observatory monthly means seeks contributors
Authors: Alexandrescu Mioara
Published: October 2006

The Department of Geomagnetism of the Institut de Physique du Globe de Paris (IPGP) has compiled a new global database of monthly mean values of geomagnetic elements. This database was originally compiled for a study of “geomagnetic jerks”—apparent sudden step changes in secular acceleration, either side of which the secular variation appears to be approximately linear—for which time series of annual mean values had been the principal source of observational data.

Researchers at IPGP encourage geomagnetic observatories throughout the world to submit their monthly mean values for inclusion in the database as soon as possible at the end of each month. The values submitted must be at least provisionally corrected to absolute values at the reference point of the observatory. The preferred method to submit data is by e‐mail in a specified format, but observatories that lack e‐mail facilities may send their results by fax or mail.
Celebrating Earth sciences
Authors: Showstack Randy
Published: October 2006

From October 11 to 17, the American Geological Institute (AGI) will sponsor the first‐ever Earth Science Week, as one of the organization's 50th anniversary initiatives.

“The goal for Earth Science Week is to have every geoscientist in the country do something in his or her community to promote the Earth sciences,” says AGI President Susan Landon.
Seismic monitoring and activity increase in California Caldera
Authors: Foulger G. R. , Malin Peter E. , Shalev E. , Julian Bruce R. , Hill David P.
Published: October 2006

Intense seismicity in the Long Valley caldera area of California last summer may have been hydrothermally driven and triggered by escalating magmatic unrest in the resurgent dome area, results from the MAMMOTH 97 Seismic Experiment suggest. The experiment involved enhanced seismic monitoring in an area that is already closely watched for earthquake activity. Sophisticated instruments were placed in the caldera's south moat section, Mammoth Mountain, and the Casa Diablo geothermal area (Figure 1). In early July, just as the enhanced network became fully operational, there was a major increase in seismic activity.

Preliminary analysis has yielded new insights into the structure and tectonics of the south moat and suggests the activity occurred above a vertical, east‐west trending, dike‐like structure beneath the moat. A series of vigorous swarms was accompanied by accelerated inflation of the resurgent dome (Figure 2). The permanent network in the area, using single‐component analog instruments, recorded more than 1,600 earthquakes of magnitude up to 3.5 during July and August, but the MAMMOTH network, with three‐component digital instruments, located about six times as many (Figure 3). About 63 “long period” (LP) earthquakes west of Mammoth Mountain were also recorded (Figures 1 and 4).
1997 Editors' citations for excellence in refereeing
Authors: Anonymous
Published: October 2006

The following reviewers have been cited by editors of AGU journals for excellence in refereeing. The editor's citation recognizes this special service to the Union, and the individuals listed are to be commended for consistently providing constructive and thoughtful reviews.

They were recognized at the 1998 Spring Meeting in Boston, Mass.
Global Warming: The Complete Briefing (Second Edition)
Authors: Hartmann Dennis L.
Published: October 2006

Enough coal exists to sustain world energy consumption growth through at least the end of the next century. If fossil carbon fuel consumption continues to increase at current rates, however, atmospheric carbon dioxide concentrations will likely more than double, probably leading to significant warming of global climate, shifts in regional climates, and sea‐level rise. Scientists and citizens throughout the world are discussing what should be done about the effects of our energy economy on the global environment.

The issue is very broad and engaging, ranging from basic issues of geoscience to economics to fundamental value systems, and it has mobilized great economic interests and concern for our global environment. We live in an interesting time when human activities have begun to compete with the global capacities of Earth to recycle the elements of life. In the coming years, we will see how the world community reacts to this challenge, and what combination of conservation, technological development, and adaptation is ultimately adopted.
Martian soil simulant available for scientific, educational study
Authors: Allen Carlton C. , Jager Karen M. , Morris Richard V. , Lindstrom David J. , Lindtsrom Marilyn M. , Lockwood John P.
Published: October 2006

Just as the world is entering an intensive and exciting phase in the exploration of Mars, a Martian soil simulant has been developed for use in scientific research, engineering studies, and education. Called JSC Mars‐1, it is a natural material obtained from volcanic ash. It approximates, within the limits of current understanding, the reflectance spectrum, mineralogy, chemical composition, grain size, density, porosity, and magnetic properties of the oxidized soil of Mars. This material is offered in limited quantities to qualified investigators and educators, without charge except for shipping.
Calibration of Seismograph Network may meet Test Ban Treaty's monitoring needs
Authors: Firbas Petr , Fuchs Karl , Mooney Walter D.
Published: October 2006

Systematic calibration of a network of seismographs could meet the seismic monitoring needs of the United Nations' comprehensive nuclear test ban treaty, a feasibility study suggests. To calibrate the network, known as the International Monitoring System (IMS), the three‐dimensional seismic structure of the Earth must be taken into account. Deep seismic sounding (DSS) profiles and global three‐dimensional seismic velocity inversions play prominent roles.

A verifiable test ban treaty is an important societal and technical goal. An essential ingredient is the ability to accurately locate seismic events, probably within a circle with a radius of 18 km, which is about 1000 km2. This would be for events with magnitude greater than 4 in continental areas.
Satellite monitoring of remote volcanoes improves study efforts in Alaska
Authors: Dean K. , Servilla M. , Roach A. , Foster B. , Engle K.
Published: October 2006

Satellite monitoring of remote volcanoes is greatly benefitting the Alaska Volcano Observatory (AVO), and last year's eruption of the Okmok Volcano in the Aleutian Islands is a good case in point. The facility was able to issue and refine warnings of the eruption and related activity quickly, something that could not have been done using conventional seismic surveillance techniques, since seismometers have not been installed at these locations.

AVO monitors about 100 active volcanoes in the North Pacific (NOPAC) region, but only a handful are observed by costly and logistically complex conventional means. The region is remote and vast, about 5000 × 2500 km, extending from Alaska west to the Kamchatka Peninsula in Russia (Figure 1). Warnings are transmitted to local communities and airlines that might be endangered by eruptions. More than 70,000 passenger and cargo flights fly over the region annually, and airborne volcanic ash is a threat to them. Many remote eruptions have been detected shortly after the initial magmatic activity using satellite data, and eruption clouds have been tracked across air traffic routes. Within minutes after eruptions are detected, information is relayed to government agencies, private companies, and the general public using telephone, fax, and e‐mail. Monitoring of volcanoes using satellite image data involves direct reception, real‐time monitoring, and data analysis. Two satellite data receiving stations, located at the Geophysical Institute, University of Alaska Fairbanks (UAF), are capable of receiving data from the advanced very high resolution radiometer (AVHRR) on National Oceanic and Atmospheric Administration (NOAA) polar orbiting satellites and from synthetic aperture radar (SAR) equipped satellites.
Preconceptions abound among students in an introductory earth science course
Authors: DeLaughter John E. , Stein Seth , Stein Carol A. , Bain Kenneth R.
Published: October 2006

Although the Third International Mathematics and Science Study found that most 8th‐grade students like science and feel that they are doing well in it [Geary, 1997], fewer than one‐quarter of U.S. adults can define the term DNA and only one in 11 knows what a molecule is [Augustine, 1998]. Hence the motivated, bright young people described by the study somehow become scientific illiterates despite the best efforts of elementary, secondary, and college‐level instructors.

This phenomenon has prompted various investigations into reasons why students have difficulty learning science. One possibility is illustrated by the famed video [Shapiro etal, 1988] showing that most of the graduating Harvard seniors surveyed confidently attributed the cause of the seasons to changes in the distance between the Earth and Sun rather than to the Earth's tilt. They had a clear conception of the answer, but it was wrong.
New map compiled of Europe's gravity field
Authors: Wybraniec Stanislaw , Zhou Shaohua , Thybo Hans , Forsberg Rene , Perchuc Edward , Lee Michael , Demianov Gleb D. , Strakhov V. N.
Published: October 2006

A gravity anomaly map of Europe was recently compiled that incorporates significant new data, especially from the eastern European countries. The map (Figure 1a), which was developed by a group of geophysicists and geodesists, goes a long way toward establishing a common and reliable database.

Geological information contained in the regional gravity field are highlighted in the map, and all known large‐scale geological structures are well coordinated with the anomaly patterns. The map offers basic gravity information for geophysical studies related to subsurface geology and large‐scale tectonic features in Europe and reinforces or supports previous interpretations of largescale tectonic features.
Satellite radar interferometry measures deformation at Okmok Volcano
Authors: Lu Zhong , Mann Dorte , Freymueller Jeff
Published: October 2006

The center of the Okmok caldera in Alaska subsided 140 cm as a result of its February– April 1997 eruption, according to satellite data from ERS‐1 and ERS‐2 synthetic aperture radar (SAR) interferometry. The inferred deflationary source was located 2.7 km beneath the approximate center of the caldera using a point source deflation model. Researchers believe this source is a magma chamber about 5 km from the eruptive source vent. During the 3 years before the eruption, the center of the caldera uplifted by about 23 cm, which researchers believe was a pre‐emptive inflation of the magma chamber. Scientists say such measurements demonstrate that radar interferometry is a promising spaceborne technique for monitoring remote volcanoes. Frequent, routine acquisition of images with SAR interferometry could make near realtime monitoring at such volcanoes the rule, aiding in eruption forecasting.
Why the United States is becoming more vulnerable to natural disasters
Authors: Van Der Vink G. , Allen R. M. , Chapin J. , Crooks M. , Fraley W. , Krantz J. , Lavigne A. M. , LeCuyer A. , MacColl E. K. , Morgan W. J. , Ries B. , Robinson E. , Rodriguez K. , Smith M. , Sponberg K.
Published: October 2006

The United States is becoming more vulnerable to natural hazards mostly because of changes in population and national wealth density—more people and more societal infrastructure have become concentrated in disaster‐prone areas. For most of the 20th century, the United States has been largely spared the expense of a catastrophic natural disaster. A great earthquake (magnitude 8 or larger) has not struck a major metropolitan area since the 1906 San Francisco earthquake. An extreme or catastrophic hurricane (Class 4 or 5) has not struck directly a major urban area since the one that hit Miami, Florida, in 1926. Yet even without such disasters, which might create losses well over $100 billion, the overall costs of natural hazards, such as extreme weather, drought, and wildfires, are estimated at $54 billion per year for the past 5 years, or approximately $1 billion per week [National Science and Technology Council, 1997].
Study provides data on active plate tectonics in southeast Asia region
Authors: Wilson P. , Rais J. , Reigber Ch. , Reinhart E. , Ambrosius B. A. C. , Le Pichon X. , Kasser M. , Suharto P. , Majid Dato' Abdul , Yaakub Dato' Paduka Awang Haji Othman Bin Haji , Almeda R. , Boonphakdee C.
Published: October 2006

A major geodynamic study has provided significant new information about the location of active plate boundaries in and around Southeast Asia, as well as deformation processes in the Sulawesi region of Indonesia and tectonic activity in the Philippine archipelago. Results also have confirmed the existence of the so‐called Sunda Block, which appears to be rotating with respect to adjacent plates.

The study, known as the Geodynamics of South and South‐East Asia (GEODYSSEA) project, has been a joint venture of the European Commission and the Association of South‐ East Asian Nations. It began in 1991 and involved a large team of European and Asian scientists and technicians studying the complex geodynamic processes and natural hazards of the region from the Southeast Asia mainland to the Philippines to northern Australia. Earthquakes, volcanic eruptions, tsunamis, and tectonically induced landslides endanger the lives of millions of people in the region, and the tectonic activity behind these natural hazards results from the convergence and collision of the Eurasian, Philippine, and Indo‐Australian Plates at relative velocities of up to 10 cm per year.
Tools used to study paleoclimate help in water management
Authors: Loosli H. H. , Lehmann B. , Aeschbach‐Hertig W. , Kipfer R. , Edmunds W. M. , Eichinger L. , Rozanski K. , Stute M. , Vaikmäe R.
Published: October 2006

The meteoric waters within active groundwater systems were in contact with the Earth's atmosphere at some time in the past, ranging from days to millions of years ago. Since conditions at the time of recharge influence the geochemical composition of water percolating into the subsurface, aquifers can be viewed as archives of past climate and environmental change. Studies based on paleoclimate records for the past 30,000 years derived from noble gases in the groundwater of Namibia, Nigeria, Vietnam, Portugal, Switzerland, and the United States confirm earlier findings of a glacial cooling of approximately 5°C in the tropics and subtropics and indicate greater cooling at high latitudes.
New, improved version of generic mapping tools released
Authors: Wessel Paul , Smith Walter H. F.
Published: October 2006

Version 3.1 of the Generic Mapping Tools (GMT) has been released. More than 6000 scientists worldwide are currently using this free, public domain collection of UNIX tools that contains programs serving a variety of research functions. GMT allows users to manipulate (x,y) and (x,y,z) data, and generate PostScript illustrations, including simple x‐y diagrams, contour maps, color images, and artificially illuminated, perspective, and/or shaded‐relief plots using a variety of map projections (see Wessel and Smith [1991] and Wessel and Smith [1995], for details.). GMT has been installed under UNIX on most types of workstations and both IBM‐compatible and Macintosh personal computers.
Detailed look at final stage of plate break‐off is target of study in Romania
Authors: Wenzel F. , Achauer U. , Enescu D. , Kissling E. , Russo R. , Mocanu V. , Musacchio G.
Published: October 2006

Geophysical experiments next year in Romania may provide insight into a common but short‐lived seismic process that can be observed and understood at only one spot on Earth at present. About 150 stations will be set up in the Vrancea area in the southeast Carpathian Mountains to, in effect, record the terminal phase of the detachment of a subducting slab of oceanic lithosphere. This is a major regional tomographic study using a large number of broadband seismometers, which will operate for 6 months. Images will be used for hazard assessment as well as for a delineation of detachment history.

Active subduction of oceanic lithosphere at convergent plate boundaries involves earthquakes, magmatism, metamorphism, and deformation—some of the most vivid manifestations of any plate tectonic process. The initiation and termination of subduction, however, remains relatively poorly understood. When convergence of lithospheric plates ceases and the suction force of the subducting plate becomes negligible, the subducting slab moves into an almost vertical position. If subduction occurs in an arcuate geometry, the slab is likely to be segmented.
Yellow River's water and sediment discharge decreasing steadily
Authors: Yang Z. S. , Milliman J. D. , Galler J. , Liu J. P. , Sun X. G.
Published: October 2006

The amount of water and sediment discharged by the Yellow River in northern China has been decreasing steadily over the past 20–25 years, such that in recent years it has contributed relatively little sediment to the Gulf of Bohai. This is quite at odds with the well‐known story in which the Yellow River has been regarded as a primary contributor of fluvial sediment to the global ocean.

If the trend of decreasing discharge continues, the environmental and economic impacts to the Yellow River delta and adjacent coastal waters could be dramatic. Already shrimp harvest from the brackish waters of the western Gulf of Bohai has decreased markedly, and there has been considerable coastal retreat along parts of the delta.
Upcoming solar maximum could affect wide range of technologies
Authors: Showstack Randy
Published: October 2006

“Sparky, get me headquarters!” the officer barks, as his radio operator frantically tries calling for assistance over the fading short‐wave. Bombs are falling and bullets flying. At the last minute, the call gets through in this anxious scene typical in many World War II movies.

The officer and Sparky may not have known that energetic releases during Solar Cycle 17, which coincided with the war years, could have caused radio signals to fade in and out, says Gary Heckman, senior space weather forecaster with the National Oceanic and Atmospheric Administration's Space Environment Center (SEC) in Boulder, Colo.
Scientists study deep geological structure between New Hebrides Arc and Eastern Australian Margin
Authors: Lafoy Y. , Van de Beuque S. , Bernardel G. , Missegue F. , Nercessian A. , Auzende J. M. , Symonds P. A. , Exon N. F.
Published: October 2006

French and Australian scientists hope that deep seismic profiling performed earlier this year in the southwest Pacific will improve understanding of the geological framework, crustal characteristics, and evolution of basins and ridges between the eastern Australian margin and the New Hebrides Trench system. The data already have indicated that the basements of several basins are thinned and oceanic, that the basements of several ridges are continental, and that, contrary to previous thinking, the Loyalty Basin was formed in late Cretaceous time.

Submerged continental fragments separated by deep ocean basins dominate the region in the west, and the Australian Plate is subducting beneath the New Hebrides Arc in the east. Subduction started in Late Miocene time [MacFarlane et al., 1988] at a rate of 12 cm/ year with a convergence direction of WSW‐ENE [Dubois et al., 1977].
Sclerosponges may hold new keys to marine paleoclimate
Authors: Swart Peter K. , Moore Michael , Charles Chris , Böhm Florian
Published: October 2006

The potential for using sclerosponges, marine organisms that secrete a hard calcerous skeleton, as paleoclimatic indicators has attracted the interest of a number of scientists. Sclerosponges are composed mainly of calcium carbonate and they are very long lived. Variations in their skeletal chemistry contain proxy information regarding their environment and that information has the potential to augment, if not supplant, data from scleractinian corals in interpreting past water temperature, salinity, and productivity over periods of 100s to 1000s of years.

Sclerosponges, or calcified demosponges, contain aragonite or calcite and a small amount of siliceous material. Lang et al. [1975] report that these sponges grow within a reef framework, under coral talus in the shallower parts of a reef less than 55 m deep and on steep surfaces of the fore‐reef between 55 and 145 m deep. The largest and most conspicuous of the sclerosponges described by those authors is Ceratoporella nicholsoni (Figure 1), which is reported to attain a diameter in excess of 1 m. These sponges are similar in growth habit to many massive vanities of scleractinian corals, the live sponge inhabiting the upper portion of the skeleton, while the lower portion of the skeleton is essentially dead.
Offshore springs and seeps are focus of working group
Authors: Burnett Bill
Published: October 2006

People have been curious about offshore springs and seeps since at least the days of the Romans. In spite of many centuries of both casual and serious observations, there has been relatively little scientific study concerning the magnitude and effects of groundwater flow into the sea. Rather, studies were performed mostly to address water resource issues. Investigations over the past decade or so have now shown that groundwater discharge, at least in some cases, may be important for geochemical budgets and ecological effects.

The Scientific Committee on Oceanic Research (SCOR) and the Land‐Ocean Interactions in the Coastal Zone (LOICZ) Project of the International Geosphere‐Biosphere Program have recently established a working group of experts to examine questions relating specifically to groundwater discharge in the coastal zone. Direct groundwater flow into the ocean is known to occur as springs and seeps in near‐shore areas in many parts of the world. Submarine springs, for example, are well known off both coasts of Florida; Mexico's Yucatan Peninsula; in several areas around the Pacific rim including Chile, Hawaii, Guam, American Samoa, and Australia; in the Persian Gulf near Bahrain; in the Mediterranean Sea off Spain, France, Italy, Greece, Syria, Lebanon, Israel, and Libya; and in many other locations.
Magnetic helicity attracts interdisciplinary participation at Chapman Conference
Authors: Canfield Richard C. , Pevtsov Alexei A.
Published: October 2006

During the last 5 years interest in magnetic helicity has grown dramatically in solar physics as a result of improved capabilities to measure and image magnetic fields. Magnetic helicity was introduced by K. Moffatt in the late 1950s as a topological invariant that describes the complexity of a magnetic field. The topological aspect of helicity is readily visualized in a Moebius strip, in which the system of interest is closed and helicity takes two forms, the writhing of the central axis of the strip and the twisting of the edges of the strip about that axis.

In many plasmas (but not in atmospheres like that of Earth, for example), helicity is conserved, just as the sum of twist and writhe is conserved in a Moebius strip. Mathematically, it is related to linking integrals, which K. F. Gauss employed to study asteroid paths on the sky. In the late 1970s the concept of magnetic helicity was introduced in laboratory plasma physics, turbulence theory, space physics, and statistical theory.
Debating complexity in modeling
Authors: Hunt Randy , Zheng Chunmiao
Published: October 2006

Complexity in modeling would seem to be an issue of universal importance throughout the geosciences, perhaps throughout all science, if the debate last year among groundwater modelers is any indication. During the discussion the following questions and observations made up the heart of the debate.

As scientists trying to understand the natural world, how should our effort be apportioned? We know that the natural world is characterized by complex and interrelated processes. Yet do we need to explicitly incorporate these intricacies to perform the tasks we are charged with? In this era of expanding computer power and development of sophisticated preprocessors and postprocessors, are bigger machines making better models? Put another way, do we understand the natural world better now with all these advancements in our simulation ability? Today the public's patience for long‐term projects producing indeterminate results is wearing thin. This increases pressure on the investigator to use the appropriate technology efficiently. On the other hand, bringing scientific results into the legal arena opens up a new dimension to the issue: to the layperson, a tool that includes more of the complexity known to exist in the real world is expected to provide the more scientifically valid answer.
Meteorologists and insurers explore extratropical transition of tropical cyclones
Authors: Malmquist David L.
Published: October 2006

Most tropical cyclones weaken as they come ashore or track poleward over colder ocean water. Yet some tropical cyclones go through a number of changes that may cause them to remain a threat after landfall or as they move poleward from the tropics. The acceleration or reintensification of these storms is associated with their transition from a tropical cyclone to a system with characteristics more common to midlatitude, extratropical storms. This “extratropical transition” (ET) is a complex and highly variable process that is currently poorly understood.
Eugene Merle Shoemaker (1928–1997)
Authors: Wilhelms Don E.
Published: October 2006

Geologist Eugene Shoemaker shaped his science into a new form, astrogeology and propelled it to the forefront of lunar and planetary exploration. In the face of formidable doubt by advocates of volcanism.he established (with Ralph Baldwin) the impact origin of craters on the Earth and the Moon. He led in alerting society to the danger posed by comets and asteroids. He was surely one of the 20th century's leading planetary scientists.
Opportunity for geophysicists to meet congressional science leaders
Authors: Kingston Margo
Published: October 2006

Scientists will flood Capitol Hill during the fourth annual Science‐Engineering‐Technology Congressional Visits Day (CVD) on April 21–22 1999, to voice their support for federal investment in science and technology. AGU encourages members to join other geoscientists for an opening day of briefings by key administration and congressional leaders followed by a day of constituent meetings with senators, representatives, and their staff. Last year, more than 250 scientists and engineers from academia and industry attended including 15 Earth scientists.

CVD provides a terrific opportunity to become part of a growing movement by scientists and engineers to remind lawmakers how indispensable the research community is to society Legislators sit up and take notice when normally reticent research scientists take a few days away from the lab and pay them a visit. It also sends a powerful message when scientists from many disciplines are seen to be working together for science in the national interest, and not just promoting their own individual pursuits. This activity smartly fits the objectives of AGU's Committee on Public Affairs to prepare and encourage AGU members to interact with their elected representatives and other decision makers as well as to increase interactions with the policy process at all levels. Previous CVD events have proven successful in part because scientists and engineers advance a simple but coherent message. Participants in this year's CVD are asked to carry two core themes: Federal investment in science and technology is important for the nation. Partnerships between government, universities, and industries mean progress, economic growth, and jobs.
Shea receives Waldo E. Smith medal
Authors: Russell Christopher , Shea Margaret A.
Published: October 2006

Margaret (Peggy) Shea was awarded the Waldo E.Smith Medal at the AGU Fall Meeting Honors Ceremony, which was held on December 8, 1998, in San Francisco, California. The medal recognizes extraordinary service to geophysics.
Tsunami in Papua New Guinea was as intense as first thought
Authors: Kawata Yoshiaka , Benson Boyd C. , Borrero José C. , Borrero José L. , Davies Hugh L. , de Lange Willem P. , Imamura Fumihiko , Letz Horst , Nott Jonathan , Synolakis Costas E.
Published: October 2006

Last July's tsunami in Papua New Guinea was as intense and catastrophic as news reports indicated, a scientific survey has found, and recommendations have been put forth to avert such a disaster in the future. The tsunami and the earthquake that generated it occurred July 17, 1998, and the International Tsunami Survey Team (ITST) began a weeklong investigation July 31. It was the ninth major tsunami and the most devastating the team has studied in the past 6 years. The team was able to precisely map the inundation and determine that media reports of extreme flows to fairly small sections of shoreline were accurate. Wave heights of 10 m were confirmed along a 25‐km stretch of coastline with maximum heights of 15 m and overland flow velocities of 15–20 m/s. Both are extreme measurements, given the moderate size of the earthquake and its aftershocks.The team noted that the force of a tsunami current on an object is roughly 1000 times that of a wind of the same speed.
Network of superconducting gravimeters benefits a number of disciplines
Authors: Crossley D. , Hinderer J. , Casula G. , Frnacis O. , Hsu H.‐T. , Imanishi Y. , Jentzsch G. , Kääriänen J. , Merriam J. , Meurers B. , Neumeyer J. , Richter B. , Shibuya K. , Sato T. , van Dam T.
Published: October 2006

A global network of superconducting gravimeters (SGs) is compiling significant data for a range of important studies spanning a number of disciplines concerned with the Earth's gravity, tides, environment, and geodetics. Among phenomena being looked at are seismic normal modes, the Slichter triplet, tidal gravity, ocean tidal loading, core nutations, and core modes. Hydrologists and volcanologists also may benefit from SG data.

The network was set up by the Global Geodynamics Project (GGP),an international program of observations of temporal variations in the Earth's gravity field. Observations began in 1997 and will continue until 2003. Eighteen SGs currently are in operation in the network (see Figures 1 and 2).
Contaminant Hydrogeology, 2nd Edition
Authors: Smith James E.
Published: October 2006

Groundwater is a valuable resource that has received much attention over the last couple of decades. Extremely large sums of money have been and will be spent on groundwater contamination problems and the public has become increasingly sensitive to groundwater issues. Groundwater contamination has even become the subject of a major Hollywood movie with the recent release of A Civil Action starring John Travolta. The high profile of groundwater contaminant problems, the associated relatively strong job market over the last 20 years, and the general shift toward an environmental emphasis in science and engineering have resulted in a sustained high demand for senior undergraduate courses and graduate programs in hydrogeology Many voice the opinion that we have seen the peak demand for hydrogeologists pass, but the placement of graduates from hydrogeology programs into career‐oriented positions has remained very high.
Thermodynamics of Crystals
Authors: Navrotsky Alexandra
Published: October 2006

Thermodynamics of Crystals is a gold mine of a references bargain with more derivations of useful equations per dollar, or per page, than almost any other book I know. Useful to whom? To the solid state physicist, the solid state chemist working the geophysicist, the rock mechanic, the mineral physicist. Useful for what? For lattice dynamics, crystal potentials, band structure. For elegant, rigorous, and concise derivations of fundamental equations. For comparison of levels of approximation. For some data and physical insights, especially for metals and simple halides. This book is a reissue, with some changes and additions, of a 1970 treatise. It ages well, since the fundamentals do not change.
Reactive Hydrocarbons in the Atmosphere
Authors: Atkinson Roger
Published: October 2006

The emissions of reactive volatile organic compounds into the atmosphere from biogenic and anthropogenic sources and the subsequent interaction of these organic compounds with oxides of nitrogen in the presence of sunlight lead to the formation of photochemical air pollution, now recognized to affect much of Europe, the United States, and many regions and urban areas elsewhere around the world. The past decade has seen the realization that emissions of organic compounds from biogenic sources (principally from vegetation) may be comparable to, or even dominate over, emissions of organic compounds from anthropogenic sources. Biogenic organics therefore play an important role in the chemistry of the troposphere and influence control strategies aimed at reducing the exposure of human populations to ozone and other manifestations of photochemical air pollution. Organic compounds also are involved in the formation of secondary organic aerosol, the formation of acids in the atmosphere, the potential for global warming, and, for chlorine‐ and bromine‐containing compounds, stratospheric ozone depletion.
Comment: Caution urged in revising earthquake hazard estimates in New Madrid Seismic Zone
Authors: Schweig Euegen S. , Gomberg Joan S. , Tuttle Martitia
Published: October 2006

In the winter of 1811–1812, the central Mississippi Valley experienced three major earthquakes, known as the New Madrid sequence. Shaking was felt across central and eastern North America, and the landscape was drastically changed, including a temporary disruption of the course of the Mississippi River and the sinking of large tracts of forest land. Careful analysis of these well‐documented effects and comparison with patterns of destruction from other earthquakes globally leads to the inference that the 1811–1812 events had magnitudes close to 8 [Johnston, 1996]. It has recently been reported in the scientific press and regional newspapers that new results of Global Positioning System (GPS) strain monitoring in the central United States indicate that seismic hazard is much lower than previously estimated [e.g., Kerr, 1999].
Interdisciplinary group explores seafloor eruption with remotely operated vehicle
Authors: Embley Robert , Baker Edward
Published: October 2006

One of the most successful open‐ocean, interdisciplinary expeditions using a remotely operated vehicle was conducted last year and is being looked on as a harbinger for future deep submergence expeditions. Unmanned systems have emerged in the past decade as an alternative to manned submersibles for deep‐ocean studies. But until now they have not proven themselves to be equal to manned vehicles in conducting multiple sampling tasks in an interdisciplinary milieu.

Last year's expedition involved extensive investigations and sampling using the Canadian Remotely Operated Vehicle for Ocean Sciences (ROPOS) [Shepherd and Juniper, 1997].A team of 33 chemists, biologists, geologists, and engineers, including a number of principal investigators from the United States and Canada, sailed on the Ronald H. Browne National Oceanic and Atmospheric Administration (NOAA) ship, with ROPOS to investigate in detail the aftermath of a diking event in the Pacific Ocean and its effect on hydrothermal chemistry and on seafloor and subseafloor biological communities. The expedition was part of the New Millennium Observatory (NeMO) project and began in earnest the in situ portion of the project in August 1998.
Radar remote sensing proposed for monitoring freeze‐thaw transitions in boreal regions
Authors: Running S. W. , Way J. B. , McDonald K. C. , Kimball J. S. , Frolking S. , Keyser A. R. , Zimmerman R.
Published: October 2006

New research is finding that satellite‐based radar remote sensing techniques are particularly well‐suited for quantifying the transition of remote boreal regions from a frozen to a thawed condition. The implications for studying global warming are far reaching. If the timing or areal extent of this freeze/thaw transition were to change significantly, measurable changes in boreal climate, hydrology, and biogeochemistry would result.

Abrupt transition from frozen to thawed conditions occurs each year over roughly 50 million km2of the Earth's remote terrestrial surface at latitudes above 40°N. Radar remote sensing works well to capture this transition because of the way electromagnetic radiation at radar wavelengths interacts with polar water molecules in solid and liquid states. Also, radar has the substantial advantages at high latitudes of both penetrating through clouds and not requiring solar illumination of the land surface.
New software package available for quantitative paleoenvironmental reconstructions
Authors: Sieger R. , Gersonde R. , Zielinski U.
Published: October 2006

The Imbrie and Kipp transfer function method (IKM) and the modern analog technique (MAT) are accepted tools for quantitative paleoenvironmental reconstructions. However, no uncomplicated, flexible software has been available to apply these methods on modern computer devices. For this reason the software packages PaleoToolBox, MacTransfer, WinTransfer, MacMAT, and PanPlot have been developed.

The PaleoToolBox package provides a flexible tool for the preprocessing of microfossil reference and downcore data as well as hydrographic reference parameters. It includes procedures to randomize the raw databases; to switch specific species in or out of the total species list; to establish individual ranking systems and their application on the reference and downcore databasessemi; and to convert the prepared databases into the file formats of IKM and MAT software for estimation of paleohydrographic parameters.
Satellite animations reveal ocean surface dynamics for shortest timescales ever
Authors: Legeckis Richard , Zhu Paul Chang Tong , Chen Shuangian
Published: October 2006

Scientists can now monitor the displacement and evolution of ocean surface thermal patterns on a shorter timescale than ever before possible, thanks to a new satellite detection method. Animations of daily composites of sea surface temperature (SST) from GOES [Menzel and Purdom, 1994” are allowing even a first‐time observer to instantly recognize the relevant patterns at timescales from several hours to several months.

Meteorologists have used GOES effectively to monitor cloud motions and to track storms, and now oceanographers can benefit too. Each individual daily composite is still partly cloud covered, but rapid display provides the appearance of continuity. So by viewing the composites rapidly the human eye can separate the fast moving residual clouds from the slower moving SST patterns associated with ocean currents, eddies, and upwelling.
Exploring Earth's oldest geological record in Greenland
Authors: Appel Peter W U. , Moorbath Stephen
Published: October 2006

Parallel with ongoing exploration of the planets, particularly those that might harbor life, attention is again focusing on deciphering the origins of life on Earth. Multidisciplinary research on ancient rocks in Greenland has become an important part of that focus and may clarify the environmental conditions of the Earth's surface at a time when those conditions were favorable for life to begin. Greenland's Isua greenstone belt (IGB) abounds in metamorphosed volcanic and sedimentary rocks from about 3.75–3.70 Gyr, a time in Earth's history that perhaps stands at the very boundary between two contrasting tectonic and environmental regimes. Deposition of the IGB rocks may be close to when Earth's atmosphere, oceans, emerging land masses, and developing sedimentary basins provided the necessary conditions for life not only to start or recommence, but also to survive. These rocks may contain chemofossils— chemical remnants of very early life—a possibility suggested by carbon isotope ratios, though not proven.
Multinational seismic investigation focuses on Rabaul volcano
Authors: Gudmundsson O. , Johnson R. W. , Finlayson D. M. , Nishimura Y. , Shimamura H. , Terashima A. , Itikarai I. , Thurber C.
Published: October 2006

An improved disaster‐reduction strategy for civil authorities and communities on the Gazelle Peninsula in Papua New Guinea is anticipated as a result of a multinational seismic investigation now under way there. Data collection has been completed but interpretation is at a preliminary stage. Volcanic eruptions in 1994 devastated the town of Rabaul and other communities on the peninsula.

The investigation, known as the Rabaul Earthquake Location and Caldera Structure (RELACS) program, is building a seismic tomography image of the Rabaul volcano that will improve the precision with which volcano‐related earthquakes can be located in real time. This will enable the Rabaul Volcanological Observatory (RVO) to interpret seismicity patterns in detail and provide better advice to civil authorities. Among other things, the scientific analytical capacity of RVO will be upgraded by improving knowledge about the subsurface structure of the caldera. Conducting the work are scientists from the Australian Geological Survey Organisation (AGSO), the Australian National University (ANU), the University of Hokkaido in Japan, and the University of Wisconsin (UW) in the United States.
Traces of Catastrophe: A Handbook of Shock‐Metamorphic Features in Terrestrial Meteorite Impact Structures
Authors: Grieve R.
Published: October 2006

Once the subject of scientific curiosity by an elite few, the study of impact events and their consequences is receiving greater attention by the larger scientific community and the public. Among the reasons for this in‐creased sensitivity are the scientific debate over the involvement of a major impact event at the Cretaceous‐Tertiary boundary, the witnessing of the impact of the fragments of comet Shoemaker‐Levey 9 on Jupiter in 1994, and the accompanying spate of made‐for‐television and Hollywood blockbuster disaster movies involving the potential demise of humanity because of a wayward asteroid or comet. As noted, however, by the author of Traces of Catastrophe, despite the growing importance of meteorite impact phenomena in terrestrial geology, the topic is not widely addressed in general geoscience textbooks. Although a large body of literature exists, it is, in general, specialized and scattered.

The book, subtitled A Handbook of Shock‐Metamorphic Features in Terrestrial Meteorite Impact Structures, is an attempt to fill this gap. It is not intended for the specialist but rather for general geoscientists and academics. It is divided into eight chapters of which only three deal exclusively with shock metamorphic features.The others provide background and details of such topics as cratering mechanics, impact flux, and crater morphology. Each chapter is designed to stand alone. Technical terms are highlighted when they are first defined in the text. The text is simply written and very readable. It is well illustrated, mostly with photographs of shocked lithologies and microscopic thin sections. At the back of the book is an extensive reference list for the reader who wishes to delve further into this fascinating subject.
Seismic predictors of El Ni˜o revisited
Authors: Walker Daniel A.
Published: October 2006

With the termination in 1998 of the most publicized El Niño in history, it may be appropriate to consider whether El Niños have a discrete triggering mechanism or whether they occur merely as the result of episodic conditions in the atmosphere and ocean. This is an important consideration because the discovery and understanding of a discrete mechanism could lead to predictions that are more reliable than those based only on secondary interactions.

Thus far, most Earth scientists agree that a discrete trigger for El Niños has not been found and is unlikely, and that differing atmospheric and oceanic parameters must be considered if there are to be reliable predictions of future El Niños. Contrary to these opinions, the process that triggers episodic seafloor spreading and higher than normal levels of reported seismic activity along portions of the East Pacific Rise (EPR) may also trigger El Niños.
Prediction in the Earth sciences and environmental policy making
Authors: Pielke Roger A. , Sarewitz Daniel , Byerly Radford , Jamieson Dale
Published: October 2006

The Earth sciences, backed by formidable arrays of data gathering and processing technologies, today offer the apparently credible promise of predicting the future of nature. Policy makers, under pressure as always to deliver public benefit at low cost, have strong incentives to accept this promise as a central response to environmental issues.

As environmental problems become more pressing and budgets for research become tighter, the importance of effective prioritization and allocation of research funds and activities will increase, as will the need for timely and effective political decision making. Thus, there is increasing need to enhance the linkages between research in the predictive Earth sciences and the needs of environmental policy makers.
Real time and the virtual outcrop improve geological field mapping
Authors: Xu Xueming , Aiken Carlos L. V. , Nielsen Kent C.
Published: October 2006

New off‐the‐shelf technologies are providing a quick way for geologists to “capture” observations in the field digitally and may become the standard tools of the early 21st century. A fully contained digital field system capable of decimeter‐level accuracy is available now for less than $10,000 and, since the technologies are rapidly evolving, it should become even more functional, accurate, portable, and cost effective.

This system relies on the Global Positioning System (GPS) at various levels of accuracy. Reflectorless laser rangefinders with anglemeasuring capabilities are used to remotely position geologic features with accuracy from centimeters to decimeters relative to the GPS positions. The laser rangefinder can also be used to reference oblique digital photography of outcrops. Data capture with lasers and GPS, integrated with digital photographs and conventional outcrop information, provide a “virtual” outcrop that is fully constrained geometrically and geographically.
Rep. George Brown dies
Authors: Showstack Randy
Published: October 2006

George E. Brown, ranking Democratic member of the U.S. House of Representatives Science Committee, died on July 15 at the age of 79 due to complications following a heart valve replacement last May. He was a strong advocate for science and environmental protection measures, and an independent thinker who sometimes found himself alone or far ahead of other people on issues.

A congressman for 34 years who represented first the 29th Congressional District and then the 42nd District in California, Brown served on the science committee since 1965 and was chair from 1991 through 1994.
In Memoriam
Authors: Anonymous
Published: October 2006

William Bernstein died on March 6,1999, at age 74. He had been a member (SPA‐Aeronomy) since 1979. Bernstein earned his physics degree at New York University in February 1944. In the late 1940s, he worked on plasma physics fusion problems at the Brookhaven Laboratory in Long Island, and on the Project Matterhorn at Princeton University where he conducted experiments associated with Martin Kruskal's theories. Bernstein also fired one of the earliest Javelin rockets in March 1970, to explore the upper atmosphere and ionosphere before, during, and after a total solar eclipse in the United States. He was part of a team who started a world‐class effort to apply plasma theory to space and ionospheric physics. In the 1960s, Bernstein also made the first of several sabbatical visits to the Culham Laboratory in the United Kingdom.