bluuebunny/crossref_metadata_2025 huggingface dataset:
Study institute assesses the state of hydrogeophysics
Authors: Hubbard Susan , Rubin Yoram
Published: October 2006

A North Atlantic Treaty Organization (NATO)‐funded Hydrogeophysics Advanced Study Institute (ASI), held at the Trest Castle in the Czech Republic in July 2002, brought together for the first time a leading group of researchers and students active in this emerging discipline. Approximately 60 hydrogeologists interested in incorporating geophysical data into their subsurface characterization problems, and geophysicists involved in subsurface hydrogeological characterization, attended the institute.

Hydrogeologists and geophysicists often use different yet complementary approaches to investigate subsurface problems. The new discipline of hydrogeophysics strives to reconcile information obtained using both hydrogeological and geophysical approaches to improve our understanding of subsurface parameters or processes. The NATO ASI was held to assess the state of the discipline, and to review recent research breakthroughs and obstacles associated with hydrogeophysics.
Toward a community coastal sediment transport modeling system: The second workshop
Authors: Sherwood Christopher R. , Harris Courtney K. , Geyer W. Rockwell , Butman Bradford
Published: October 2006

Models for transport and the long‐term fate of particles in coastal waters are essential for a variety of applications related to commerce, defense, public health, and the quality of the marine environment. Examples include: analysis of waste disposal and transport and the fate of contaminated materials; evaluation of burial rates for naval mines or archaeological artifacts; prediction of water‐column optical properties; analysis of transport and the fate of biological particles; prediction of coastal flooding and coastal erosion; evaluation of impacts of sea‐level or wave‐climate changes and coastal development; planning for construction and maintenance of navigable waterways; evaluation of habitat for commercial fisheries; evaluation of impacts of natural or anthropogenic changes in coastal conditions on recreational activities; and design of intakes and outfalls for sewage treatment, cooling systems, and desalination plants.
Isotope studies in large river basins: A new global research focus
Authors: Gibson John J. , Aggarwal Pradeep , Hogan James , Kendall Carol , Martinelli Luiz A. , Stichler Willi , Rank Dieter , Goni Ibrahim , Choudhry Manzoor , Gat Joel , Bhattacharya Sourendra , Sugimoto Atsuko , Fekete Balazs , Pietroniro Alain , Maurer Thomas , Panarello Hector , Stone David , Seyler Patrick , Maurice‐Bourgoin Laurence , Herczeg Andrew
Published: October 2006

Rivers are an important linkage in the global hydrological cycle, returning about 35%of continental precipitation to the oceans. Rivers are also the most important source of water for human use. Much of the world's population lives along large rivers, relying on them for trade, transportation, industry, agriculture, and domestic water supplies. The resulting pressure has led to the extreme regulation of some river systems, and often a degradation of water quantity and quality For sustainable management of water supply agriculture, flood‐drought cycles, and ecosystem and human health, there is a basic need for improving the scientific understanding of water cycling processes in river basins, and the ability to detect and predict impacts of climate change and water resources development.
An overview of stochastic modeling of groundwater flow and transport: From theory to applications
Authors: Dagan Gedeon
Published: October 2006

The stochastic modeling of groundwater has developed considerably in the last twenty years and a large body of knowledge has accumulated. However, there is also room for criticism: the community has evolved into a specialized one and research has started to address esoteric topics. Furthermore, in spite of its expansion, the stochastic approach hasn't yet become a routine tool of hydrological modeling.

The main message of this article is an appeal for application of stochastic modeling to practical problems on a regular basis (see motto above). This is regarded as a task of utmost importance and high priority Furthermore, in spite of outstanding problems, it is surmised that the accumulated knowledge makes it possible.
Potential of airborne geophysical capabilities discussed
Authors: Finn Carol A. , Anandakrishnan Sridhar , Goodge John , Panter Kurt , Siddoway Christine , Wilson Terry
Published: October 2006

Antarctica is a key element in Earth's geodynamic and climatic systems. Nevertheless, on the eve of the 50th anniversary of the International Geophysical Year, we lack fundamental geologic and geophysical data from the deep interior of this vast continent. Meager exposures record the 3500‐million‐year history of a continent that participated in the formation and breakup of both the Rodinia and Gondwana super‐continents. It continues to be tectonically active today although its kinematic relationship to the global plate circuit and its role as sub‐ strate to the world's major ice sheets remain in question.
Conference promotes study of ecohydrology of semi‐arid landscapes
Authors: Newman Brent D. , Sala Osvaldo , Wilcox Bradford P.
Published: October 2006

Greater scientific understanding is needed of how semi‐arid landscapes and other dry environments function, particularly from the ecohydrologic perspective. This need is driven by the growing urgency of finding answers for such troublesome issues as the sustainability of ecosystems, inadequacy of water supplies, degradation of water quality and the effects of environmental change at local, regional, and global scales. Because of the tight coupling between ecologic and hydrologic processes in semi‐arid landscapes, these issues must be addressed from an ecohydrologic perspective.

Ecohydrology has been defined as “the sub‐discipline shared by the ecological and hydrological sciences that is concerned with the effects of hydrological processes on the distribution, structure, and function of ecosystems, and with the effects of biotic processes on elements of the water cycle” [Nuttle, 2002]. While not a new term, ecohydrology is receiving increased attention, largely because of the recognition that more interdisciplinary or holistic approaches are required to adequately address applied and basic environmental research problems [e.g.,Baird and Wilby, 1999; Gupta, 2000; Gurnell et al., 2000;Horton, 1998; May et al., 1999;Nuttle, 1999, 2002; and Rodriguez‐Iturbe, 2000].
Dam removal in the United States: Emerging needs for science and policy
Authors: Doyle Martin W. , Stanley Emily H. , Harbor Jon M. , Grant Gordon S.
Published: October 2006

The aging of America's dams, coupled with increasing awareness of their environmental costs, has brought dam decommissioning and removal to the attention of the scientific community, management agencies, and the general public. Over the past two years, dam removal has been the focus of special sessions at the annual meetings of numerous scientific societies (e.g., American Association for the Advancement of Science, American Geophysical Union, Ecological Society of America, Association of American Geographers) as well as groups focusedon bridging science and policy [Heinz Center, 2002].

Here we briefly examine why dam removal has emerged as a critical issue, the realities of ongoing dam removal efforts and the current policy vacuum, and the need for expanded scientific research to support policy development.
Bathymetry from space is now possible
Authors: Sandwell David T. , Gille Sarah T. , Orcutt John , Smith Walter H. F.
Published: October 2006

A new satellite altimeter mission to map the deep ocean bathymetry and gravity field five times better than existing global maps is being considered. This mission, which would be 16 times faster and cheaper than mapping the sea floor with conventional multibeam systems, would be used to probe the internal structure of the continental margins, and estimate sea floor topography and roughness spectra for geological, oceanographic, and climatological purposes (see boxed sidebar). Of course, the highest‐resolution bathymetry maps come from shipboard systems, but so far, only 10% of the sea floor has been surveyed, and it will take 125 ship‐years to map the deep oceans at a cost of about one billion dollars.

The accuracy of current altimeter‐derived maps is limited by ranging noise and short mission duration. A new altimeter with improved technology and a non‐repeating orbit could provide accuracy to 1 mGal within 6 years (http://fermi.jhuapl.edu/abyss). In the deep ocean, where there is little sediment cover, gravity and topography are highly correlated, so that gravity can be used to predict topography, but there is a fundamental resolution limit of π times the mean ocean depth, which is ∼12 km full‐wavelength, due to upward continuation. On the shallow continental margins, the gravity field reveals variations in sediment and crustal structure.
Comment on “Survey tracks current position of South Magnetic Pole” and “Recent acceleration of the north magnetic pole linked to magnetic jerks”
Authors: Campbell Wallace H.
Published: October 2006

In recent months, two articles have appeared in Eos reporting new positions of the north [Newitt et al., 2002] and south [Barton, 2002] magnetic poles from on‐site measurements of locations for vertical magnetic field dip. Readers should be advised that these reported positions are neither magnetic poles nor geophysically important locations. First let us review some facts about our Earth's field.

When a magnetic field can be represented by an axially symmetric dipole pattern similar to the electric field from a pair of equal and opposite electric charges, the axis of this magnetic field is called a pole. For the Earth, Gilbert [1958] first called attention to this dipole feature in his 1600 publication De Magnete. With the magnetic dipole center location corresponding to the Earth's geographic center, and the Earth completely spherical, the exit position of the magnetic dipole corresponded to the location of a fully vertical dip of the field. Global maritime exploration that started around the time of the epic 1492 Columbus voyage greatly depended on the ship compass for navigation and on magnetic declination maps for guidance. It was only natural that considerable interest in special expeditions to locate the mysterious Arctic and Antarctic Earth magnetic poles subsequently arose.
Integrating complexity of social systems in natural hazards planning: An example from Caracas, Venezuela
Authors: Vranes Kevin , Czuchlewski Kristina R.
Published: October 2006

In December 1999, days of heavy rain on steep slopes north of Caracas, Venezuela triggered massive mud and debris flows, killing tens of thousands. Partly in response to this disaster, a multidisciplinary team of urban planners and Earth scientists from Columbia University recently developed a framework plan for building disaster resilience into the Venezuelan capital region. After assessing the complex intersection of urban geography with severe seismic and hydrologic hazards, substantial recommendations were made to local and regional authorities on future hazards mitigation.

Areas found most at risk in the Caracas region include the transportation and utility infrastructure and the friable building stock of squatter settlements. Recognizing realistic economic and socio‐political constraints on implementing change, a prioritized list of goals and activities was constructed, and recommendations made along various time scales. Immediate disaster‐avoidance goals (to be completed within 1 to 5 years) include strengthening critical infrastructure nodes, housing stock, and emergency services. More intermediate goals (5 to 10 years) focus on upgrading fragile housing units, creating detailed hazard maps across the city, and incorporating disaster education into cultural activities. Recommended activities for the long term (beyond 10 years) include creating a fully redundant transportation and water delivery network, establishing legitimate land title for squatters, and re‐locating critical facilities currently in high‐risk areas.
Use of protection zones and land management restore contaminated groundwater in Denmark
Authors: Thomsen Richard , Thorling Lark
Published: October 2006

The sustainable water supply project discussed in this article is the first in Danish history to use protection zones to safeguard groundwater from the effects of agricultural production. As experience with groundwater protection zones was very limited 10 years ago, the project involved comprehensive and systematic monitoring to determine the effects of the protection zones on groundwater quality.

The establishment of protection zones around waterworks is a simple and inexpensive way to safeguard the drinking water resource. As more than 99% of Denmark's drinking water supply derives from the nation's naturally pure groundwater, protection of the groundwater resource from agricultural and industrial contamination is accorded high priority Agricultural use of nitrate fertilizers can considerably deteriorate the quality of the groundwater. In Aarhus County alone, more than 100 out of 600 waterworks have been closed due to nitrate contamination.
The North Atlantic Oscillation: Climatic Significance and Environmental Impact
Authors: Lifland Jonathan
Published: October 2006

A new AGU book, The North Atlantic Oscillation: Climatic Significance and Environmental Impact, edited by James W. Hurrell, Yochanan Kushnir, Geir Ottersen, and Martin Visbeck, investigates the current theories, models, and observations of the NAO and assesses future directions for research. The book is the first on this important phenomenon, the most prominent and recurring weather pattern over the Northern Hemisphere. In this issue, Eos talks with lead editor, James Hurrell. Hurrell is deputy section head of the Climate Analysis Section of the National Center for Atmospheric Research, where he has contributed to the International Panel on Climate Change assessments, and works with the international research program on climate variability and predictability.
Ezekiel's vision: Visual evidence of Sterno‐Etrussia geomagnetic excursion?
Authors: Raspopov Oleg M. , Dergachev Valentin A. , Goos'kova Elena G.
Published: October 2006

In the Eos article,“Ezekiel and the Northern Lights: Biblical Aurora Seems Plausible” (16 April 2002), Siscoe et al. presented arguments showing that coronal auroras can occur at low latitudes under the condition of increased geomagnetic dipole field strength. From this standpoint, they give an interpretation of the “reported” Ezekiel's vision (the Bible's Book of Ezekiel in the Old Testament). The site of the Ezekiel's vision was about 100 km south of Babylon (latitude ˜32° N, longitude ˜5°E), and the date of the vision was around 593 B.C.

Auroral specialists believe that Ezekiel's vision was inspired by a very strong magnetic storm accompanied by coronal auroras at low latitudes. However, as justly noted by Siscoe et al. [2002],to adopt this interpretation, several questions should be answered. Can auroras be seen at the latitude where Ezekiel reportedly was? More important, can they reach a coronal stage of development, which is what the vision requires? Was the tilt of the dipole axis favorable? Was the general level of solar activity favorable? The principal question is, no doubt, the second one.
An Introduction to Geophysical Exploration: Third Edition
Authors: Tatham Robert H.
Published: October 2006

Finding a modern textbook that covers all aspects of exploration geophysics is difficult, but An Introduction to Geophysical Exploration certainly fills the bill. Appropriate for an introductory course addressing a range of techniques the book's breadth is demonstrated by comprehensive inclusion of non‐seismic exploration methods. In fact, half of the book is devoted to non‐seismic methods, providing students with a permanent reference to these infrequently applied exploration methods.

This book came to my attention while I was ordering textbooks for a course in exploration geophysics only to find that the text of my choice was out of print. I quickly substituted An Introduction to Geophysical Exploration, and it has served the class well, including senior‐level undergraduates and first‐year graduate students in both soft‐rock geology and geophysics. The material is comprehensive and well organized. The non‐seismic topics include not only chapters on potential fields— one each on gravity and magnetic methods— but also chapters on electrical and electromagnetic methods, including ground‐penetrating radar (GPR). Short chapters on radiometric surveying and borehole logging are also provided.
Geodesy is not just for static measurements any more
Authors: Chao Benjamin F.
Published: October 2006

After three decades and three orders of magnitude of advances, space geodesy is poised for prime time in observing the integrated mass transports that take place in the Earth system, from high atmosphere to the deep interior of the core. As such, space geodesy has become a new remote sensing tool, in monitoring climatic and geophysical changes with ever‐increasing sensitivity and resolution.

The transports of mass and energy are key processes that determine the dynamics of our Earth system. The Earth system can be conveniently viewed through its components, so‐called geophysical fluids—the atmosphere, hydrosphere, cryosphere, biosphere, lithosphere, and the deep interior of mantle and cores. All geophysical fluids undergo a host of mass transports for various reasons, external as well as internal. Studying these processes is undoubtedly a most interdisciplinary field in all of Earth sciences. However, mass transport has not received due attentions. For example, all ocean general circulation models (GCMs) working today do not correctly conserve the water mass; instead, they conserve the water volume under the Boussinesq approximation. Neither do the atmospheric GCMs in conserving the dry air mass, including those used daily for weather forecasts. A most critical piece in the global water mass puzzle, the large‐scale land hydrological and cryospheric mass budget remains least known.
Fluid flow in sub‐sea floor processes and future ocean drilling
Authors: Ge S. , Bekins B. , Bredehoeft J. , Brown K. , Davis E. E. , Gorelick S. M. , Henry P. , Kooi H. , Moench A. F. , Ruppel C. , Sauter M. , Screaton E. , Swart P.K. , Tokunaga T. , Voss C.I. , Whitaker F.
Published: October 2006

Studies indicate that fluids are present in the Earth's crust from the surface to at least 10 to 15 km. Fluids play a vital role in linking various physical and chemical processes by transporting energy and solutes at a wide range of spatial and temporal scales. Below the sea floor, fluids are involved in seismogenic zone dynamics, global chemical cycles, gas hydrate formation, mid‐oceanic hydrothermal systems, biological community development, and sediment diagenetic processes (Figure 1). Fluid fluxes through the sea floor and oceanland interfaces play a major role in the global water cycle, but these fluxes remain to be quantified. While the main scientific question centers on the role of fluid in transporting heat and mass in various settings, the following specific issues form the foundation for a better understanding of the role of fluids in subsea floor processes:
Phosphorus deficiency in the Atlantic: An emerging paradigm in oceanography
Authors: Ammerman James W. , Hood Raleigh R. , Case Darin A. , Cotner James B.
Published: October 2006

Nitrogen, iron, and silica are widely considered to be the most important nutrients that limit phytoplankton growth in the world's oceans. Though clearly important in lakes, the role of phosphorus has been largely ignored in the ocean. In part, this is because of early studies that suggested there was excess phosphate (P) relative to the needs of the phytoplankton in open ocean waters. Thanks to recent studies at the Hawaiian Ocean Time (HOT) series station (Station ALOHA) in the North Pacific subtropical gyre [Karl et al., 2001, and references therein], there is a growing appreciation of the potential importance of phosphorus as a limiting nutrient in subtropical Pacific waters.
New interpretation of glacial history of Cape Cod may have important implications for groundwater contaminant transport
Authors: Mulligan Ann , Uchupi Elazar
Published: October 2006

Fresh water resources of sufficient quantity and quality are critical for maintaining societies and for supporting additional growth and development. When these resources are threatened or compromised, as can occur through the release of hazardous compounds, additional stress is placed on the water supply system from loss of the resource and changes in the demand structure.

In western Cape Cod, Massachusetts, such problems are currently being encountered as a result of contaminant releases from the Massachusetts Military Reservation (MMR). An effective long‐term response to subsurface contamination requires, among other things, determining the lithology, stratigraphy, and structure of aquifer materials and their effects on groundwater flow and contaminant transport. A recent review and analysis of subsurface data across Cape Cod offers a new interpretation of the geologic history of the Cape, with potential implications for groundwater issues facing western Cape Cod (the Upper Cape).
Should Memphis build for California's earthquakes?
Authors: Stein Seth , Tomasello Joseph , Newman Andrew
Published: October 2006

State and local authorities in parts of the central U.S. that are at risk from earthquakes in the New Madrid Seismic Zone (NMSZ) are considering adopting a new building code that would increase the earthquake resistance of new buildings to levels similar to those in southern California.

Here, we argue against this proposal on the dual grounds that the earthquake hazard has been overestimated, and that the costs of the proposed change are likely to far exceed the potential benefits. Instead, we recommend weighing the costs and benefits of alternative strategies that could yield reasonable seismic safety at significantly lower cost.
2003 Fellows Citations
Authors: Anonymous
Published: October 2006

AGU congratulates the forty‐one distinguished scientists who were selected by a committee of their peers to be AGU Fellows for 2003. This selection was based on the individuals' attainment of acknowledged eminence in a branch of geophysics.

The number of Fellows selected annually is limited to no more than 0.1% of the AGU membership. The names of the new Fellows are listed here, along with citations recognizing their specific achievements.
MODIS data used to study 2002 fires in Kalimantan, Indonesia
Authors: Fuller Douglas O.
Published: October 2006

Smoke and haze blanketed western Indonesia during August and September 2002, signaling the arrival of another El Niño event in Southeast Asia. Although not as severe as the 1997–1998 El Niño event, the 2002 El Niño produced drought conditions in western Indonesia that favored extensive biomass burning in lowland areas of Borneo, Sumatra, and Sulawesi, three of the largest islands that form part of the vast Indonesian archipelago. Data derived from the Moderate Resolution Imaging Spectrometer (MODIS) on board the NASA Terra satellite showed that most of the burning during 2002 occurred in central and western Kalimantan (Indonesian Borneo), where forests are being cleared to make way for industrial oil palm and pulp plantations.

Comparison of fire data from several different satellite sensors also reveals that fires detected in Kalimantan during 1997 appeared more numerous (Figure 1) and burned over a longer period (Figure 2) than fires that burned in late 2002 (see discussion below). This result is consistent with recent El Niño observations that characterize the current event as moderate relative to the 1997–1998 event (see http://www.cpc.ncep.noaa.gov/ products/analysis_monitoring/enso_advisory/).
Curators of sea floor and lakebed samples celebrate 25 years of service
Authors: Mix Alan , Conard Bobbi , Broda Jim , Carey Steve , Firth John , Janecek Tom , Lotti‐Bond Rusty , Moore Carla , Norris Richard , Schnurrenberger Doug
Published: October 2006

Research on marine geological and lake sediment benefits from community repository facilities that are supported by the U.S. National Science Foundation (NSF) at eight U.S. institutions. These facilities house sediment cores, sediment trap samples, and sea floor rocks, and distribute data and materials for national and international scientific use. For more than 30 years, in partnership with participating universities, NSF has provided support for these community service facilities, recognizing that storage and distribution of these unique materials leverage the best and most cost‐effective science for the global community.

Curators representing the participating institutions meet semi‐annually to coordinate repository activities, to set standards for archival, and to maintain policies that maximize research use of materials. These planning meetings began in 1977, when lack of coordination among institutions limited access to the broader community. The inaugural meeting of 18 interested repositories yielded a preliminary sediment description scheme and a first community data base, which opened in 1979 with records on 5000 sediment cores hosted by the National Oceanic and Atmospheric Administration's National Geophysical Data Center (NGDC) and World Data Center for Marine Geology and Geophysics in Boulder, Colorado.
Global Paleomagnetic Data Base developed into its visual form
Authors: Pisarevsky Sergei A. , McElhinny Michael W.
Published: October 2006

The Global Paleomagnetic Database (GPMDB) created and developed by M.W. McElhinny and J. Lock is used by researchers all over the world. The well‐known version of this data base is in Microsoft Access format, a user‐friendly interface that requires no programming skills. The next step in developing these data bases lies in the visualization of data and the integration of the paleomagnetic data with Geographical Information Systems (GIS). One of the most popular GIS software applications among Earth scientists is Arc View, which was developed by the Environmental Systems Research Institute (ESRI). A new Arc View 3.1 application visualizes the GPMDB and provides a range of new possibilities for interactive search, analysis, and plate tectonic applications of paleomagnetic data.
Trends in marine dissolved oxygen: Implications for ocean circulation changes and the carbon budget
Authors: Joos Fortunat , Plattner Gian‐Kasper , Stocker Thomas F. , Körtzinger Arne , Wallace Douglas W. R.
Published: October 2006

Recent measurements and model studies have consistently identified a decreasing trend in the concentration of dissolved O2 in the ocean over the last several decades. This trend has important implications for our understanding of anthropogenic climate change. First, the observed oceanic oxygen changes may be a signal of the beginning of a reorganization of large‐scale ocean circulation in response to anthropogenic radiative forcing. Second, the repartitioning of oxygen between the ocean and the atmosphere requires a revision of the current atmospheric carbon budget and the estimates of the terrestrial and oceanic carbon sinks as calculated by the Intergovernmental Panel on Climate Change (IPCC) from measurements of atmospheric O2/N2.
Quantitative Seismology, Second Edition
Authors: Lay Thorne
Published: October 2006

As recently as 1980, anyone seeking a rigorous treatment of the fundamentals of elastodynamics relevant to the rapidly maturing field of seismology had to delve into a host of primary sources, some of which were rather obscure or difficult to obtain. Classical texts in this field tended to focus on limited topics and to treat some areas either superficially or in excessive depth. Graduate education in the field of seismology tended to reflect local faculty expertise and interests, often with compendia of handwritten notes, inconsistent notation, and variable generality. That situation was dramatically changed with the appearance of the first edition of Quantitative Seismology, a two‐volume set that distilled the key foundations of elastodynamics for linear elastic materials into an accessible and satisfyingly thorough presentation of seismological theory
Quantifying hazard and risk assessments at active volcanoes
Authors: Zimbelman David , Watters Robert J. , Bowman Steve , Firth Ian
Published: October 2006

Mass‐waste events from volcanic edifice collapse constitute one of the world's most catastrophic natural hazards. To date, hazards associated with collapse have generally been considered evenly dispersed about a volcano. However, these events are often referred to as sector collapses because only part of a volcano's summit and flank collapse. This is because volcanoes do not have uniform geology or geotechnical characteristics and, thus, their hazard distributions are also non‐uniform. To assess the non‐uniform distribution of geologic controls on volcano stability, we have developed a method that combines field‐based geologic mapping and sampling with mineralogic, petrologic, stable‐isotope geochemical, and geotechnical laboratory studies. Our results provide methods that help quantify the non‐uniform stability of stratovolcanoes and significantly improve volcanic hazard and risk assessments.
Anonymous reviews: Self‐serving, counterproductive, and unacceptable
Authors: Beck Myrl E.
Published: October 2006

Recently I became involved in an incident in which a manuscript was rejected on the advice of two anonymous reviewers and an anonymous associate editor. This re‐activated my long‐standing disgust at the entire system of anonymous reviews and pushed me—finally—into doing something about it. A few weeks or months ago, I read a similar protest, somewhere—one much more persuasive than I am likely to write—but my high‐mileage brain has misplaced its provenance. Consider this a “high‐five” to that misplaced author.
Network assesses earthquake potential in Italy's southern Alps
Authors: Battaglia Maurizio , Zuliani David , Pascutti Davide , Michelini Alberto , Marson Iginio , Murray Mark H. , Bürgmann Roland
Published: October 2006

On 6 May 1976, a magnitude 6.4 earthquake struck the Friuli region of northeastern Italy near the towns of Gemona and Venzone. Although it was not as large as some previous earthquakes in Italy, its severe ground motion (up to 0.36 g) affected an area with numerous historical towns, resulting in 989 fatalities and 45,000 people left homeless. At least four other destructive earthquakes with epicentral intensity greater than or equal to IX on the Mercalli‐Cancani‐Sieberg scale have occurred in the Friuli region in the last 5 centuries (1511, 1700, 1794, and 1928) [Slejko et al., 1999].

To better understand the seismic hazards of this vulnerable area, a network of continuously operating Global Positioning System (GPS) receivers—the Friuli Regional Deformation Network (FReDNet)—was installed to monitor the regional distribution of crustal deformation (Figure 1).
The need for global, satellite‐based observations of terrestrial surface waters
Authors: Alsdorf Doug , Lettenmaier Dennis , Vörösmarty Charles
Published: October 2006

River discharge as well as lake and wetland storage of water are critical terms in the surface water balance, yet they are poorly observed globally and the prospects for improvement from in‐situ networks are bleak [e.g.,Shiklomanov et al., 2002; IAHS, 2001;Stokstad, 1999]. Indeed, given our basic need for fresh water, perhaps the most important hydrologic observations that can be made in a basin are of the temporal and spatial variations in discharge. Gauges measuring discharge rely on flow converging from the upstream catchment to a singular in‐channel cross section. This approach has successfully monitored many of the world's densely inhabited and typically heavily engineered basins for well over a century. However, much of the globally significant discharge occurs in sparsely gauged basins, many with vast wetlands that lack flow convergence (e.g., Figures 1 and 2); thus leading to poorly defined values of runoff at local, regional, and continental scales.
Reply to “Comment on “Should Memphis build for California's earthquakes?” From A.D. Frankel”]
Authors: Stein Seth , Tomasello Joseph , Newman Andrew
Published: October 2006

Carl Sagan observed that “extraordinary claims require extraordinary evidence.” In our view, A.D. Frankel's arguments (see accompanying Comment piece) do not reach the level required to demonstrate the counter‐intuitive propositions that the earthquake hazard in the New Madrid Seismic Zone (NMSZ) is comparable to that in coastal California, and that buildings should be built to similar standards.

This interchange is the latest in an ongoing debate beginning with Newman et al.'s [1999a] recommendation, based on analysis of Global Positioning System and earthquake data, that Frankel et al.'s [1996] estimate of California‐level seismic hazard for the NMSZ should be reduced. Most points at issue, except for those related to the costs and benefits of the proposed new International Building Code 2000, have already been argued at length by both sides in the literature [e.g.,Schweig et al., 1999; Newman et al., 1999b, 2001; Cramer, 2001]. Hence,rather than rehash these points, we will try here to provide readers not enmeshed in this morass with an overview of the primary differences between our view and that of Frankel.
Uncertain Science… Uncertain World
Authors: Lempert Robert
Published: October 2006

Why doesn't society act in the face of overwhelming evidence that human influences are changing the Earth's climate? Henry Pollack devotes his book, Uncertain Science… Uncertain World, to addressing one important reason. Much about climate science is highly uncertain, he argues; and as a general rule, most well‐educated citizens don't understand the nature of scientific uncertainty. Thus, they have difficulty understanding competing claims made by advocates in the policy debate and in internalizing the extent of the problem.

A distinguished professor of geophysics at the University of Michigan, as well as a participant in many public debates involving science, Pollack aims to help lay readers understand the role of uncertainty in science. “In making comparisons and analogies with uncertainties that exist in science and everyday life,” he writes, “my goal is to help readers to understand and accommodate scientific uncertainties in much the same way that they deal with other uncertainties in life.”
Record‐breaking height for 8000‐year‐old tsunami in the North Atlantic
Authors: Bondevik Stein , Mangerud Jan , Dawson Sue , Dawson Alastair , Lohne Øystein
Published: October 2006

One of the largest Holocene sub‐marine slides mapped on Earth is the Storegga slide offshore Norway [Bugge, 1987] (Figure 1). Approximately 3500 km3 material slid out and generated a huge tsunami dated to about 7300 14C yr BP [Bondevik et al., 1997a], or ca 8150 calendar years BP. The tsunami is known from onshore deposits in Norway [Bondevik et al., 1997a], on the Faroe Islands [Grauert et al., 2001], and in Scotland [Dawson et al., 1993]. Of these, the tsunami deposits in western Norway reaches the highest elevation, indicating a runup of 10–12 m. In this article, we demonstrate that at the Shetland Islands between Norway and Scotland (Figure 1), this tsunami reached onshore heights at least 20 m above the sea level of that time.
Bush administration releases Climate Science Plan
Authors: Showstack Randy
Published: October 2006

The Bush Administration's final version of its climate change research plan, issued on 24 July, is an ambitious and long‐awaited document which promises to guide the government's science efforts for the next decade.

The Climate Change Science Program Strategic Plan establishes five overall goals for the next decade, including improving knowledge of the planet's past and present climate and environment, reducing uncertainty of climate projections, and understanding the sensitivity and adaptability of ecosystems and human systems to global change.
U.S. states predict water shortages
Authors: Showstack Randy
Published: October 2006

Thirty‐six U.S. states anticipate suffering water shortages under normal water conditions within the next 10 years, state water managers indicated in a survey released by the U.S. General Accounting Office (GAO) on 9 July.

The report to Congress, entitled, “Freshwater Supply: States' Views of How Federal Agencies Could Help them Meet the Challenges of Expected Shortages,” is the first comprehensive national assessment of water availability and use since a 1978 report by the U.S. Water Resources Council.
Improving knowledge of impact cratering: Bringing together “Modelers” and “Observationalists”
Authors: Herrick Robert R. , Pierazzo Elisabetta
Published: October 2006

Formation of a planetary‐scale impact crater hundreds of meters to hundreds of kilometers in diameter involves the interplay of multiphase processes occurring over size‐ and time‐scales that range over many orders of magnitude. To further complicate matters, a hypervelocity impact into geologic materials has never been observed at greater than laboratory scales. Understanding the formation process clearly is a very complicated problem that requires a highly interdisciplinary approach. Significant work has been done recently in several key areas of impact studies, but in many respects, there is a “disconnect” among groups employing different approaches. This pertains, in particular, to modeling versus observations.
Outstanding student paper awards
Authors: Anonymous
Published: October 2006

The following members in the Space Physics & Aeronomy and the Tectonophysics Sections received Outstanding Student Paper Awards at the 2002 AGU Fall Meeting in San Francisco, California. (Winners in other sections will be announced in subsequent issues of Eos.)
Tectonic Evolution of the Bering Shelf‐Chukchi Sea‐Arctic Margin and Adjacent Landmasses, Special Paper 360
Authors: Bartley John M.
Published: October 2006

Tectonic study of continental orogens involves distilling knowledge about lithospheric processes from a relatively small number of geologically intricate, unique examples. Thus, we may anticipate that each example has something to teach us, and, conversely, that there is scientific value in advancing knowledge of every example. From this perspective, GSA Special Paper 360 represents a significant contribution.

Tectonic Evolution of the Bering Shelf‐Chukchi Sea‐Arctic Margin and Adjacent Landmasses promises and delivers a great deal of new or newly compiled data pertinent to regional tectonics of the western Arctic. Owing to its geographic remoteness and severe climate, this area has heretofore been poorly known. Data presented range from seismic reflection profiles to metamorphic thermobarometry from isotopic geochronology to biostratigraphy from petrochemistry to paleomagnetism,from regional seismotectonics to geologic maps.
The Seismic Wavefield, Volume II: Interpretation of Seismograms on Regional and Global Scales
Authors: Tromp Jeroen
Published: October 2006

Volume II of Brian Kennett's book, The Seismic Wavefield, is entitled “Interpretation of Seismograms on Regional and Global Scales.” The first volume in this series is entitled “Introduction and Theoretical Development,” and was published in 2001. The current volume is divided into three parts, 17 chapters, and an appendix. By way of numerous observations and illustrations, this volume introduces the reader to the various regional and global seismic phases. Here is where one learns how to distinguish Pn from Pg, how to unravel the PKP traveltime branches, and where to look for Love. The writing is clear and concise, the references are plentiful, and the quality of the figures is excellent.
Extreme volcanism on Io: Latest insights at the end of Galileo era
Authors: Kargel Jeffrey , Carlson Robert , Davies Ashley , Fegley Bruce , Gillespie Alan , Greeley Ronald , Howell Robert , Jessup Kandis Lea , Kamp Lucas , Keszthelyi Laszlo , Lopes Rosaly , MacIntyre Timothy , Marchis Franck , McEwen Alfred , Milazzo Moses , Perry Jason , Radebaugh Jani , Schaefer Laura , Schmerr Nicholas , Smythe William , Spencer John , Williams David , Zhang Ju , Zolotov Mikhail
Published: October 2006

Galileo has now completed 7 years exploring Jupiter. The spacecraft obtained breathtaking views of the four major satellites, and studied Jupiter's clouds and atmospheric composition, rings, small satellites, and magnetic field. It had five successful close flybys and many distant observations of Io. Scientists already knew from Voyager and Earth‐based astronomy that Io is by far the most volcanically active object in the solar system. Galileo has given us stunning color panoramas of Io's surface and unprecedented close views of erupting volcanoes (Figure 1) and the largest active flows observed anywhere. Among recent discoveries about Io, perhaps most astonishing since Voyager, is that some lavas possess emission temperatures greater than any lavas erupted on Earth today and possibly since the start of Earth's geologic history. The Io science community has identified three alternative interpretations of Io's hottest lavas: (1) ultramafic material similar to komatiite; (2) superheated lava; or (3) an ultra‐refractory substance deficient in silica and rich in Ca‐Al oxides.
MODIS detects oil spills in Lake Maracaibo, Venezuela
Authors: Hu Chuanmin , Müller‐Karger Frank E. , Taylor Charles (Judd) , Myhre Douglas , Murch Brock , Odriozola Ana L. , Godoy Gonzalo
Published: October 2006

Starting December 2002, the oil industry operating in and around Lake Maracaibo in Venezuela suffered a series of accidents (Figure 1). Fires, the sinking of two barges, rupture of oil pipelines, spills from floating oil storage and transfer stations, and malfunctioning of oil extraction platforms led to extensive oil spills. Local and federal Venezuelan government oil industry experts directly observed the series of spills from aircraft, helicopter, and various surface vessels. The spills were recorded in December by official photography and video of leaking infrastructure, and unofficial recordings continued in January and February 2003 (http://wwwcomlago.com.ve/fotosvideos. html).

These surveys did not provide sufficient spatial or temporal coverage to assess the magnitude, area covered, or duration of the spills. Clear images of the spill were captured with NASAs Moderate Resolution Imaging Spectroradiometer (MODIS), however. MODIS is effectively a sophisticated digital camera launched aboard the Terra satellite in December 1999, and aboard the Aqua satellite in April 2002 [Esaias et al., 1998; http://modis.gsfc.nasa.gov]. Its medium‐resolution bands (250 and 500 m resolution) are available to the public, and have great potential in coastal monitoring. This article demonstrates how MODIS can provide basic and critical assessments of oil spills.
Comment on “When Earth's freezer door is left ajar”
Authors: Alley Richard B.
Published: October 2006

As a glaciologist, I wish I could believe Hezi Gildor's [2003] provocative Forum article, that warming favors ice growth up to rather high temperatures, and that the future may hold more beautiful glaciers for my colleagues and me to study. Unfortunately far too much evidence indicates that warming will reduce the extent of ice on Earth, and has done so under a wide range of past conditions, including the ice age cycling of the Pleistocene [e.g., Rahmstorf, 2002].

For most of the Earth's glaciers today, accumulation of snowfall in colder places is removed primarily by melting in warmer places. Anything that affects either accumulation or melting, including temperature, precipitation, cloud cover, relative humidity wind speed, debris cover, seasonality of these, and more, can affect glacier balance, as can a host of ice‐flow processes [e.g., Paterson, 1994; Oerlemans, 2001].
GEOTRACES: Studying the global marine biogeochemistry of trace elements and isotopes
Authors: Frank Martin , Jeandel Catherine , Anderson Robert F. , Henderson Gideon , Francois Roger , Sharma Mukul
Published: October 2006

There is a growing international interest among geochemists and oceanographers in building a coordinated global study of the marine biogeochemical cycles of selected trace elements and isotopic tracers. This is reflected by the increasing numbers of contributions to corresponding special sessions at meetings such as the 2001 AGU Fall Meeting, the 2002 Goldschmidt Meeting, and the 2003 European Geophysical Union Annual Meeting. With support from the U.S. National Science Foundation's Chemical Oceanography program, the Centre National de Recherche Scientifique in France, the University Paul Sabatier, and the Observatoire Midi‐Pyrénées, an international planning workshop was recently held to define the scientific goals for such a global study.

Eighty‐five scientists from 15 nations representing fields as diverse as physical oceanography, dynamic and biogeochemical ocean modeling, ocean geochemistry, and paleoceanography attended the workshop. There was a broad consensus recognizing the need for a coordinated research effort in the spirit of the 1970s Geochemical Ocean Sections Study (GEOSECS) program, which led to fundamental advances in the understanding of ocean circulation and biogeochemical cycles. Dramatic advances have been made in a nalytical techniques, chemical sensors, and modeling since the days of GEOSECS, but progress in understanding the global biogeochemical cycles of trace elements and their isotopes has been limited by the lack of a large‐scale coordinated effort. Workshop participants enthusiastically endorsed the development of such a program, for which the name GEOTRACES was adopted.
Jurassic dipole low defined from land and sea data
Authors: McElhinny Michael W. , Larson Roger L.
Published: October 2006

Estimates of the Earth's magnetic dipole moment through geologic time have been obtained using paleo‐intensities determined from igneous rocks. These measurements, normalized by conversion to virtual dipole moments (VDMs), were used by Prévot et al. [1990] to suggest there was an extended period named the ‘Mesozoic Dipole Low’ (MDL) from about 180 Ma to about 135 Ma. Subsequent reviews of the paleo‐intensity data appeared to indicate a minimum of about one‐third of the Cenozoic value occurred between about 180 and 120 Ma [Kono and Tanaka, 1995; Perrin and Shcherbakov, 1997].

Recently there has been considerable debate regarding the existence of the MDL from those who have both made and reviewed more recent paleo‐intensity determinations [Selkin and Tauxe, 2000; Heller et al., 2002; Goguitchaichvili et al., 2002; Biggin and Thomas, 2003; Thomas and Biggin, 2003]. None of these authors has used or discussed the evidence available from marine magnetic anomalies, although McElhinny and McFadden [2000] pointed out that the minimum in this proposed MDL could be seen also in the marine magnetic anomaly record from the Jurassic Quiet Zone (JQZ). The JQZ is defined by a factor‐of‐four decrease in anomaly amplitudes with increasing age from about anomaly M19 (˜144 Ma) in the Pacific [Larson and Hilde, 1975; Cande et al., 1978].
Proterozoic East Gondwana: Supercontinent Assembly and Breakup, Special Publication 206
Authors: Meert Joseph G.
Published: October 2006

The Mozambique Belt, which runs the length of eastern Africa, was thought to have formed during the collision of a fully assembled east Gondwana with west Gondwana during the East Africa Orogen (EAO). Subsequent work demonstrated that the elements of the Gondwana super‐continent were distributed along the margins of Laurentia in the antecedent super‐continent of Rodinia. It was quickly recognized that west Gondwana was an amalgam of cratonic elements assembled in the latter part of the Neoproterozoic during the Brasiliano and “Pan‐African” orogenic episodes (ca. 630–500 Ma). East Gondwana was traditionally depicted in Rodinia as a coherent landmass composed of Australia, the East Antarctic eraton, India, Madagascar, and Sri Lanka.