bluuebunny/crossref_metadata_2025 huggingface dataset:
Warm oceans raise land temperatures
Authors: Hoerling Martin P. , Xu TaiYi , Bates Gary , Kumar Arun , Jha Bhaskar
Published: October 2006

During 2004, sea surface temperatures (SSTs) were the third warmest in the past 125 years, land surface temperatures were the fourth warmest, and globally averaged temperatures likewise ranked fourth highest [Levinson, 2005]. This article presents evidence that SSTs contributed significantly to the widespread terrestrial and global tropospheric warmth.

Every ocean witnessed warm sea surface conditions in 2004, with only the middle latitudes of the Southern Ocean experiencing below average values (Figure 1, top). Much of this warmth was concentrated north of 30°S and included a weak El Nino event in the tropical central Pacific. Terrestrial warmth in 2004 was seen at all locations between 45°N and 45°S.The greatest departures from average temperatures occurred over interior Eurasia and western North America, which experienced increases of up to 2°C (Figure 1, middle). Consistent with the considerable warmth of ocean and land surfaces, much of the global troposphere was also warm in 2004. The thermal expansion of the tropospheric column, whose top is roughly at the 200‐millibar pressure surface, is demonstrated by the increase in elevation of that surface worldwide (Figure 1, bottom).
A case for short duration of Deccan Trap Eruption
Authors: Sen Gautam , Borges Melroy , Marsh Bruce D.
Published: October 2006

Earth's geologic past has been punctuated by episodes of voluminous outpouring of lava that flooded large areas of continents and oceans, giving rise to what are commonly called flood basalt provinces. These flood basalt eruptions often coincided with major stratigraphic boundaries and mass extinction events.

The Deccan Traps of India are a muchstudied example of a flood basalt province that erupted at or near the Cretaceous/Tertiary (K/T) boundary 65 million years ago. These lavas reach a maximum thickness of 2.7 kilometers at the Western Ghats of India.
Altair unmanned aircraft system achieves demonstration goals
Authors: Fahey David W. , Churnside James H. , Elkins James W. , Gasiewski Albin J. , Rosenlof Karen H. , Summers Sara , Aslaksen Michael , Jacobs Todd A. , Sellars Jon D. , Jennison Christopher D. , Freudinger Lawrence C. , Cooper Michael
Published: October 2006

In the early morning of 15 November 2005, the unmanned Altair aircraft returned to Gray Butte Airfield, north of Los Angeles, Calif., after completing an 18.4‐hour mission over the eastern Pacific Ocean. The flight was the last in a series undertaken by the U.S. National Oceanic and Atmospheric Administration (NOAA) in its Unmanned Aircraft System (UAS) Demonstration Project. The successful flight series has helped start the era of unmanned flights in service of environmental goals. Altair cruised at altitudes in the lower stratosphere (13 kilo‐meters; ∼43,000 feet), collecting atmospheric data with a 140‐kilogram payload of both remote and in situ instruments.
Survey provides guidance for consortium's hydrologic measurement facility
Authors: Robinson David , Selker John , Bowden Breck , Duncan Jonathan , Durant John , Hooper Rick , Jacobs Jennifer , Knight Rose‐Mary
Published: October 2006

The Consortium of Universities for the Advancement of Hydrologic Sciences, Inc. (CUAHSI) began the Hydrologic Measurement Facility (HMF) program in June 2005 to advance hydrologic measurement capability within the research community. To provide guidance for this effort, a recent survey assessed the level of need among the hydrological sciences community for community instruments and facilities.The survey aimed to identify technologies and methodologies that could make major advances in the hydrologic sciences.

Between 1 November 2005 and 15 January 2006,363 responses were returned. (45% from hydrologists, 15% soil scientists, 12% geophysicists, 11% biogeochemists, 3% ecologists, 3% geomorphologists, and 11% other disciplines).
Larson receives Geodesy Section Award
Authors: Axelrad Penina , Larson Kristine M.
Published: October 2006

Kristine M. Larson received the Geodesy Section Award on 23 May 2006 at the 2006 Joint Assembly in Baltimore, Md. The award is given in recognition of major advances in geodesy
Atlantic hurricane trends linked to climate change
Authors: Mann Michael E. , Emanuel Kerry A.
Published: October 2006

Increases in key measures of Atlantic hurricane activity over recent decades are believed to reflect, in large part, contemporaneous increases in tropical Atlantic warmth [e.g., Emanuel, 2005]. Some recent studies [e.g., Goldenberg et al., 2001] have attributed these increases to a natural climate cycle termed the Atlantic Multidecadal Oscillation (AMO), while other studies suggest that climate change may instead be playing the dominant role [Emanuel, 2005; Webster et al., 2005].

Using a formal statistical analysis to separate the estimated influences of anthropogenic climate change from possible natural cyclical influences, this article presents results indicating that anthropogenic factors are likely responsible for long‐term trends in tropical Atlantic warmth and tropical cyclone activity. In addition, this analysis indicates that late twentieth century tropospheric aerosol cooling has offset a substantial fraction of anthropogenic warming in the region and has thus likely suppressed even greater potential increases in tropical cyclone activity.
Near‐surface geophysics: A new focus group
Authors: Slater Lee , Knight Rosemary , Singha Kamini , Binley Andrew , Atekwana Estella
Published: October 2006

AGU has established the new Near‐Surface Geophysics (NS) focus group in response to rapidly growing scientific studies of the ‘critical zone,’ the near‐surface environment where complex interactions exist between processes in hydrogeology geochemistry and geobiology among other disciplines.

This new focus group will concentrate on processes occurring in the top 100 meters of the critical zone, which supports human infrastructure, provides water and mineral resources, is the disposal zone for much of the population's waste, represents a key component of many hazards assessments, and is the interface between land and atmosphere for many of the biogeochemical cycles that sustain life.
Creating effective flood mitigation policies
Authors: Fraser James C. , Doyle Matrin W. , Young Hannah
Published: October 2006

Hurricane Katrina in 2005 increased awareness of the vulnerability of people and property in flood‐prone areas of the United States, particularly repetitively flooded properties. Prior to Katrina, repetitive loss properties cost the United States over $200 million annually [General Accounting Office (GAO), 2004].

The U.S. Congress passed the Bunning‐Bereuter‐Blumenauer Flood Insurance Reform Act of 2004 (FIRA) to maintain the fiscal soundness of the National Flood Insurance Program (NFIP) and ease the burden of repetitive loss properties on NFIP Federal calculations indicate that every dollar spent on mitigation activities creates a $3.65 savings in future disaster recovery costs, and the U.S. Federal Emergency Management Agency (FEMA) estimates that over $1 billion are spared annually through flood mitigation and floodplain management programs [GAO, 2005a].
Acoustic navigation and communication for High‐Latitude Ocean Research Workshop
Authors: Lee Craig M. , Gobat Jason I.
Published: October 2006

Recent community reports on autonomous platforms and Arctic observing [U.S. National Science Foundation, 2002; Proshutinsky et al., 2004; Rudnick and Perry, 2003] identify the development of under‐ice navigation and telemetry technologies as one of the critical factors limiting the scope of high‐latitude measurement efforts. Advances in autonomous platforms (profiling floats, drifters, long‐range gliders, and propeller‐driven vehicles) promise to revolutionize ocean observations, providing unprecedented spatial and temporal resolution for both short‐duration process studies and multiyear efforts designed to quantify long‐timescale environmental changes. This new generation of platforms facilitates access to logistically difficult regions where weather and remoteness challenge conventional techniques, making them attractive for polar regions. These platforms could provide persistent, high‐resolution, basin‐wide sampling in ice‐covered regions and operate near the critical ice‐water interface.
Giant sand waves at the mouth of San Francisco Bay
Authors: Barnard Patrick L. , Hanes Daniel M. , Rubin David M. , Kvitek Rikk G.
Published: October 2006

A field of giant sand waves, among the largest in the world, recently was mapped in high resolution for the first time during a multibeam survey in 2004 and 2005 through the strait of the Golden Gate at the mouth of San Francisco Bay in California (Figure la). This massive bed form field covers an area of approximately four square kilometers in water depths ranging from 30 to 106 meters, featuring more than 40 distinct sand waves with crests aligned approximately perpendicular to the dominant tidally generated cross‐shore currents, with wavelengths and heights that measure up to 220 meters and 10 meters, respectively.

Sand wave crests can be traced continuously for up to two kilometers across the mouth of this energetic tidal inlet, where depth‐averaged tidal currents through the strait below the Golden Gate Bridge exceed 2.5 meters per second during peak ebb flows. Repeated surveys demonstrated that the sand waves are active and dynamic features that move in response to tidally generated currents. The complex temporal and spatial variations in wave and tidal current interactions in this region result in an astoundingly diverse array of bed form morphologies, scales, and orientations. Bed forms of approximately half the scale of those reported in this article previously were mapped inside San Francisco Bay during a multibeam survey in 1997 [Chin et al., 1997].
A network for standardized ocean color validation measurements
Authors: Zibordi Giuseppe , Holben Brent , Hooker Stanford B. , Mélin Frédéric , Berthon Jean‐François , Slutsker Ilya , Giles David , Vandemark Doug , Feng Hui , Rutledge Ken , Schuster Gregory , Al Mandoos Abdulla
Published: October 2006

The Aerosol Robotic Network (AERONET), originally developed to evaluate aerosol optical properties and validate satellite retrievals of those properties at various scales with measurements from worldwidedistributed autonomous Sun photometers [Holben et al., 1998],since January 2006 has been extended to support marine remote sensing and monitoring applications. This new network component, called AERONETOcean Color (AERONET‐OC), provides the additional capability of measuring the radiance emerging from the sea—the ‘water‐leaving radiance’—with modified Sun photometers installed on offshore platforms such as lighthouses, oceanographic towers, and derricks.

AERONET‐OC is proving to be instrumental in supporting satellite ocean color validation activities through standardized measurements performed at different sites with identical measuring systems and protocols, calibrated using a single reference source and method, and processed with the same code. Recent investigations [Zibordi et al., 2006] suggest that in order to generate accurate climate data records from remote sensing data, time series of in situ measurements from a cadre of AERONET‐OC sites could play a major role in the assessment and merging of radiometric products from different ocean color missions.
A future for drifting seismic networks
Authors: Simons Frederik J. , Nolet Guust , Babcock Jeff M. , Davis Russ E. , Orcutt John A.
Published: October 2006

Earth models in which seismic wave speeds vary only with depth are sufficiently well constrained to accurately locate earthquakes and calculate the paths followed by seismic rays [Engdahl et al., 1998]. The differences between observations and theoretical predictions of seismograms in such onedimensional Earth models can be used to reconstruct the three‐dimensional (3‐D) wave speed distribution in the regions sampled by the seismic waves by a procedure known as seismic tomography, a technique akin to medical CAT scanning.

Caused by thermal, compositional, and textural variations, wave speed anomalies remain the premier data source to fully understand the structure and evolution of our planet [Romanowicz, 2003], from the scale of mantle convection and the mechanisms of heat transfer from core to surface to the interaction between the deep Earth and surface processes such as plate motion and crustal deformation.
Reconsidering the textbook
Authors: Bierman Paul , Massey Christine , Manduca Catherine
Published: October 2006

Is the printed science textbook a massive, slow moving dinosaur headed for extinction, doomed by its inability to evolve in the face of a fast moving technology bolide? In 10 years, will students still carry printed tomes in their backpacks, or will electronic media have replaced the textbook, leaving it about as useful as yesterday's typewriter or adding machine? With the explosion of digital technology in students' lives and the increasing awareness among geosciences faculty that established teaching techniques are becoming less effective for this generation of students, the time is ripe to reconsider the textbook.

More than 50 leading scientists, educators, and technology professionals ‘reconsidered the textbook’ during a recent intensive threeday workshop funded by the U.S. National Science Foundation (NSF), which was held at the U.S. National Academy of Sciences (NAS), in Washington, DC. Through small and large group discussions, the assembled group examined the current state of the textbook and its relationship to the growing number of electronic tools that also serve as learning resources for today's students. Together, the participants looked forward and—based on their knowledge of student learning, technology, and effective educational strategies—imagined the textbook of the future.
Recent seismovolcanic crisis in northern Afar, Ethiopia
Authors: Yirgu Gezahegn , Ababa Addis , Ayele Atalay
Published: October 2006

A 60‐kilometer‐long rift segment ruptured in north central Afar, Ethiopia, in September 2005. This rupture followed a short but intensive period of volcanic and tectonic activity during which time more than 162 earthquakes (magnitudes 4.1—5.2) occurred and a 400‐meter‐long and 80‐meter‐wide volcanic vent opened (Figure l ). For its spatial extent and amount of opening, this event ranks as the largest observed rifting sequence to have occurred on land, comparable to the 10‐yearlong Krafla (Iceland, 1975–1984) episode along a mid‐ocean ridge.

The Afar depression is a triple rift junction where the Red Sea and Gulf of Aden spreading ridges emerge on land and meet the northern extension of the East African Rift (Figure 2a). The junction lies above or near a mantle plume [e.g., Courtillot et al., 1984; Montelli et al., 2004]. The floor of the depression is composed mostly of basalt lava emplaced during Plio‐Quaternary times over the last three million years [e.g., Kidane et al., 2003]. Huge and elongate basaltic shield volcanoes conspicuously rise above basalt fields and sand plains. The Afar depression is one of the hottest and driest places on Earth, yet its many pastoralists support large herds by distilling water from geothermal vents (known locally as boinas).
Marine investigations of Greece's Santorini Volcanic Field
Authors: Sigurdsson Haraldur , Carey Steven , Alexandri Matina , Vougioukalakis Georges , Croff Katherine , Roman Chris , Sakellariou Dimitris , Anagnostou Christos , Rousakis Grigoris , Ioakim Chrysanti , Goguo Aleka , Ballas Dionysis , Misaridis Thanassis , Nomikou Paraskevi
Published: October 2006

The most recent major explosive eruption of the Santorini volcano in Greece—around 3600 years before present (B.P.), often referred to as the Minoan eruption—is one of the largest volcanic events known in historical time and has been the subject of intense volcanological and archeological studies [Druitt et al., 1999]. The submarine volcano Kolumbo, located seven kilometers northeast of Santorini and associated with Santorini's tectonic system, erupted explosively in 1650 A.D., resulting in fatalities on the island of Thera [Fouqué, 1879]. A large fraction of the erupted products from the Minoan eruption has been deposited in the sea but, up to now, only has been studied in distal marine sediments.

As part of a collaborative project between the University of Rhode Island (Narragansett), the Hellenic Centre of Marine Research (Athens, Greece), and the Institute of Geology and Mineral Exploration (Athens), a marine geological survey was conducted around Santorini from April to June 2006. he new work now shows that the volume of the Minoan eruption may be comparable to that of the largest known historical eruption, the 1815 eruption of Tambora in Indonesia [Sigurdsson and Carey, 1989]; provides insights into the depositional processes and size of the Minoan eruption; and led to the discovery of important submarine hydrothermal vents with active mineralization.
Are Scientists underestimating climate change?
Authors: Pittock A. Barrie
Published: October 2006

The consensus view of climate scientists, as represented by the 2001 Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report, is that the enhanced greenhouse effect likely will lead to global average surface warming by 2100 of between 1.4° and 5.8°C,and global sea level rise of between 9 and 88 centimeters. This assumes the climate sensitivity is in the range 1.5°–4.5°C for an equilibrium doubling of preindustrial carbon dioxide concentrations, and the Special Report on Emissions Scenarios (SRES) range of emissions scenarios [IPCC, 2000]. However, recent developments suggest that this dated IPCC view might underestimate the upper end of the range of possibilities and shift the probabilities toward an increasing risk of greater warmings and sea level rises by 2100.
How long will our interglacial be?
Authors: Crucifix Michel , Berger André
Published: October 2006

In a recentEosarticle (87(3), 27, 2006), Broecker and Stocker criticizeRuddimaris[2003] hypothesis of an anthropogenic origin to the Holocene carbon dioxide (C02) rise.

Broecker and Stocker note the analogy between the Earth's orbital configuration 400,000 years ago and the current configuration by aligning theEPICA Community Members[2004] ice core record for the deglaciation that occurred 430,000–420,000 years ago, with the last deglaciation (20,000–10,000 years ago). Considering that the two situations are analogous, it appears that no glacial inception, marking the end of the Holocene, should have occurred by now.
The reawakening of Alaska's Augustine volcano
Authors: Power John A. , Nye Christopher J. , Coombs Michelle L. , Wessels Rick L. , Cervelli Peter F. , Dehn Jon , Wallace Kristi L. , Freymueller Jeffery T. , Doukas Michael P.
Published: October 2006

Augustine volcano, in south central Alaska, ended a 20‐year period of repose on 11 January 2006 with 13 explosive eruptions in 20 days. Explosive activity shifted to a quieter effusion of lava in early February, forming a new summit lava dome and two short, blocky lava flows by late March (Figure 1).

The eruption was heralded by eight months of increasing seismicity, deformation, gas emission, and small phreatic eruptions, the latter consisting of explosions of steam and debris caused by heating and expansion of groundwater due to an underlying heat source.
Maintaining of the Eastern South Pacific Oxygen Minimum Zone (OMZ) off Chile
Authors: Paulmier A. , Ruiz‐Pino D. , Garçon V. , Farías L.
Published: October 2006

Processes regulating OMZs persistence in the oxygenated ocean remain poorly understood. Four cruises (21°–30°S) and fixed‐point monitoring (36°S) between 2000 and 2002 using techniques adapted to O2 conditions as low as 1 μM allow a preliminary analysis of the entire Chilean OMZ structure. A shallow OMZ is observed in the three studied areas, although its structure differs. Off northern and central Chile, the OMZ is a permanent feature, more pronounced at the coast than further offshore. On the shelf, it forms in spring and erodes in fall. A conceptual model of two intermittent active or passive phases (intense or low biogeochemical O2 consumption) is proposed as a key mechanism for the local OMZ maintaining. The highest O2 consumptions are paradoxically favoured at the oxycline when the OMZ is less intense as offshore and on the shelf in spring and fall, suggesting a control by O2 availability of the OMZ remineralization.
Comparison of SCIAMACHY and AIRS CO2 measurements over North America during the summer and autumn of 2003
Authors: Barkley Michael P. , Monks Paul S. , Engelen Richard J.
Published: October 2006

Atmospheric CO2 volume mixing ratios retrieved by the AIRS and SCIAMACHY instruments, are compared over North America during the summer and autumn of 2003. Examination of the deviations of the CO2 volume mixing ratios, relative to the mean CO2 background measured by each instrument, reveal large‐scale coincidental spatial features that develop over the course of the year. Furthermore, the time series of the monthly CO2 anomalies show a seasonal cycle signal that is characteristic of the upper and lower troposphere to which AIRS and SCIAMACHY are respectively sensitive to. This comparison demonstrates that there is a general consistency between the CO2 distributions retrieved by AIRS and SCIAMACHY, when considering the different vertical sensitivities of the instruments.
Discrepancy of mass transport between the Northern and Southern Hemispheres among the ERA‐40, NCEP/NCAR, NCEP‐DOE AMIP‐2, and JRA‐25 reanalysis
Authors: Zhao Yufei , Li Jianping
Published: October 2006

The atmospheric mass transfer between the Northern Hemisphere (NH) and the Southern Hemisphere (SH) across the equator is calculated from the ERA‐40, the NCEP/NCAR (NCEP 1), the NCEP‐DOE AMIP‐2 (NCEP 2) and the Japanese 25‐year Reanalysis (JRA‐25) and explored for trends which have some notable differences, even contrary phase in the mean annual cycle. The hemispheric and global mean surface pressure anomalies have the coincident trends for the four datasets. The varieties of mass flux and mean surface pressure anomalies are comparatively coincident in ERA‐40 and JRA‐25 (when the mass flux is northerly (southerly), the mean surface pressure in NH increases (decreases)), but almost contrary verdict in NCEP 1. There's been a notable improvement in NCEP 2 upon NCEP 1, however, NCEP 2 seems likely still not as good as ERA‐40 and JRA‐25. Furthermore, the research also expands to 60°S–60°N.
Receiver function migration image of the deep structure in the Bohai Bay Basin, eastern China
Authors: Chen Ling , Zheng Tianyu , Xu Weiwei
Published: October 2006

We apply a receiver function poststack migration method to image the crustal and upper mantle structures beneath the Bohai Bay Basin, eastern China. The thick sediments of the basin appear to have a substantial influence on the migrated image of the deep structure. By using the surface reflected PpPs multiples instead of the commonly used Ps converted phases, a curved Moho is coherently imaged, showing a thinned crust of ∼30 km in the basin area compared with the >40‐km thick crust in the west mountain range. By incorporating the sedimentary velocity model into migration, both the 410‐km and the 660‐km discontinuities present a simple structural feature with relatively flat topography within the basin's interior, although possible local structural complexities may exist at the base of the upper mantle around the boundary areas of the basin. The mantle transition zone is on average 10–15 km thicker than the global average, reflecting a cold lower upper mantle environment that is distinct from the warm shallow upper mantle of the region.
Changes in tropical cyclone precipitation over China
Authors: Ren Fumin , Wu Guoxiong , Dong Wenjie , Wang Xiaoling , Wang Yongmei , Ai Wanxiu , Li Weijing
Published: October 2006

The Tropical Cyclone (TC) Precipitation (TCP) is partitioned from the station observations in China using the Objective Synoptic Analysis Technique (OSAT). The TCP spatial distribution, its ratio to total annual rainfall, the changes in the TCP volume, and the annual frequency of the torrential TCP events during the period 1957∼2004 are examined with a focus on their long‐term trends in this study. Tropical cyclones significantly contribute to the annual rainfall in southern, southeastern, and eastern China, including Taiwan and Hainan islands. The TCP in most of the southeastern coastal regions can be more than 500 mm a year, accounting for 20∼40% of the total annual precipitation. Together with interdecadal and interannual variations, significant downward trends are found in the TCP volume, the annual frequency of torrential TCP events, and the contribution of TCP to the annual precipitation over the past 48 years. The downward trends were accompanied with the decreases in the numbers of TCs and typhoons that affected China during the period 1957–2004. These changes strongly suggest that China has experienced decreasing TC influence over the past 48 years, especially in terms of the TCP.
Hydrogeological investigations at the Membach station, Belgium, and application to correct long periodic gravity variations
Authors: Van Camp M. , Vanclooster M. , Crommen O. , Petermans T. , Verbeeck K. , Meurers B. , van Dam T. , Dassargues A.
Published: October 2006

A comprehensive hydrogeological investigation regarding the influence of variations in local and regional water mass on superconducting gravity measurements is presented for observations taken near the geodynamic station of Membach, Belgium. Applying a regional water storage model, the gravity contribution due to the elastic deformation of the Earth was derived. In addition, the Newtonian gravity effect induced by the local water mass variations was calculated, using soil moisture observations taken at the ground surface (about 48 m above the gravimeters). The computation of the gravimetric effect is based on a digital elevation model with spatially discretized rectangular prisms. The obtained results are compared with the observations of a superconducting gravimeter (SG). We find that the seasonal variations can be reasonably well predicted with the regional water storage model and the local Newtonian effects. Shorter‐period effects depend on the local changes in hydrology. This result shows the sensitivity of SG observations to very local water storage changes.
Recordings of geomagnetically induced currents and a nowcasting service of the Finnish natural gas pipeline system
Authors: Viljanen A. , Pulkkinen A. , Pirjola R. , Pajunpää K. , Posio P. , Koistinen A.
Published: October 2006

The geomagnetically induced currents (GIC) in the Finnish natural gas pipeline have been measured at one site in southern Finland since November 1998. We give an overview of this long and uniform time series covering one sunspot maximum. We also briefly discuss the conventional magnetic activity indices K and Ak, and, additionally, the range of the magnetic field and of its time derivative, as indicators of the GIC activity. The measured GIC data formed the basis of the development of a nowcasting service (GIC Now!), which was implemented within the European Space Agency Space Weather Applications Pilot Project. The service provides a near‐real‐time view of the geomagnetic activity level and nowcast estimates of GIC and pipe‐to‐soil voltages in the Finnish natural gas pipeline system. We describe the operation and validation of this service in this paper.
Predicting the distribution of bed material accumulation using river network sediment budgets
Authors: Wilkinson Scott N. , Prosser Ian P. , Hughes Andrew O.
Published: October 2006

Assessing the spatial distribution of bed material accumulation in river networks is important for determining the impacts of erosion on downstream channel form and habitat and for planning erosion and sediment management. A model that constructs spatially distributed budgets of bed material sediment is developed to predict the locations of accumulation following land use change. For each link in the river network, GIS algorithms are used to predict bed material supply from gullies, river banks, and upstream tributaries and to compare total supply with transport capacity. The model is tested in the 29,000 km2 Murrumbidgee River catchment in southeast Australia. It correctly predicts the presence or absence of accumulation in 71% of river links, which is significantly better performance than previous models, which do not account for spatial variability in sediment supply and transport capacity. Representing transient sediment storage is important for predicting smaller accumulations. Bed material accumulation is predicted in 25% of the river network, indicating its importance as an environmental problem in Australia.
Generation of coarse‐scale continuum flow models from detailed fracture characterizations
Authors: Karimi‐Fard M. , Gong B. , Durlofsky L. J.
Published: October 2006

A procedure for developing coarse‐scale continuum models from detailed fracture descriptions is developed and applied. The coarse models are in the form of a generalized dual‐porosity representation, in which matrix rock and fractures exchange fluid locally while large‐scale flow occurs through the fracture network. The methodology developed here introduces local subgrids to resolve dynamics within the matrix and provides appropriate coarse‐scale parameters describing fracture‐fracture, matrix‐fracture, and matrix‐matrix flow. The geometry of the local subgrids, as well as the required parameters for the coarse‐scale model, are determined from local flow solutions using the underlying discrete fracture model. The method is applied to two‐ and three‐dimensional single‐phase and two‐phase flow problems, and the accuracy of the coarse models is assessed relative to fully resolved discrete fracture simulations. For the cases considered, it is shown that the technique is capable of generating highly accurate coarse models with many fewer unknowns than the detailed characterizations, and speedups of about a factor of 100 are achieved.
A continuous time random walk approach to transient flow in heterogeneous porous media
Authors: Cortis Andrea , Knudby Christen
Published: October 2006

We propose a new physical interpretation of the diffusion process for the piezometric head h(x, t) in heterogeneous aquifers based on the continuous time random walk (CTRW) theory. For the typical heterogeneities considered in this work, we find that a CTRW based diffusion equation for h(x, t) provides better fits to the transient flow simulations than the classical diffusion equation (DE). The DE is found to be a special case of the CTRW diffusion equation. The results of this work have clear implications for the interpretation of pumping tests and what information can be extracted from them.
Tectonostratigraphic Terranes of the Circum‐Pacific Region
Authors: Van der Voo Rob
Published: October 2006

Have you always wondered where the Tujunga, Baldy, and Cortez terranes might be located today, let alone during the Cretaceous or early Tertiary? This book may provide the answer, because in a little less than 600 pages for $32, which includes a marvelously produced color map of the entire Circum‐Pacific region, one can read almost everything one wants to know about Earth's “ring of fire” and its displaced or suspect terranes. The printing, proofreading, illustrations, and references are all of the highest caliber, and the book is handsomely produced indeed. In page‐by‐page reading, I found maybe five typographical errors, but I will spare you the details.

The contents of the book are divided into five parts, comprising principles or applications of terrane analysis and four unequally long parts on the four quadrants of the Pacific coasts. The northeast quadrant includes Alaska, the Canadian Cordillera, the U.S. coastal and Rocky Mountain belts, and Mexico; the northwest includes Kamchatka, northeast Asia, China, Japan, Taiwan, and the Philippines; the southwest section has articles on Australia, Malaya, Indonesia, New Zealand, and Antarctica; and the southeast comprises the Andes from Colombia to southern Chile. The book offers introductory text for beginning students of terrane analysis, as well as plenty of useful details and data for the expert who needs a handy reference volume. Subject matter or emphasis ranges from hydrocarbon generation in marginal basins, biogeography, paleomagnetism, geochronology, and structural and metamorphic aspects to stratigraphy and shows how the entire discipline of geological sciences is contributing to terrane analysis. There is literally something here for everyone in solid Earth science.
The long‐term ecological research program
Authors: Swanson Frederick J. , Franklin J. F.
Published: October 2006

Major developments have emerged in the field of ecology as a result of taking a long‐term approach to both basic and applied research [Strayer, 1986]. In recognition of both the advantages of long‐term research programs and the historical difficulty of sustaining such research efforts, the National Science Foundation (NSF) instituted its Long‐Term Ecological Research (LTER) Program in 1980 [Callahan, 1984]. The LTER Program has a number of important links with the geosciences and is likely to play a significant role in work on terrestrial, freshwater, and estuarine ecosystems within the International Geosphere‐Biosphere Program (IBGP); it is thus a good time for us to begin communicating with geoscientists who are helping to shape IGBP.
The Global Water Cycle Geochemistry, and Environment
Authors: Bricker Owen P.
Published: October 2006

In the preface the authors state, as reasons for producing this book, the need for an appropriate undergraduate‐level text on water chemistry and the desire to provide broader coverage of atmospheric and environmental chemistry than is found in other existing books on this topic. They have attempted to write a book that could be understood by almost anyone with an elementarv knowledge of science, yet could still serve as a source of geochemical and environmental data for researchers in a variety of fields. The authors have succeeded admirably in achieving these difficult goals.
The relationship between volcanic eruptions and climate change: Still a conundrum?
Authors: Self Stephen , Rampino Michael R.
Published: October 2006

What is the relationship between volcanic eruptions and climate change? More than 200 years after the connection was first proposed, it remains a thorny question. This article provides a brief historical overview of the problem and a review of the various data bases used in evaluating volcanic events and associated climatic change. We use the term “climate” to describe changes in the atmosphere over wide regions for periods of several months and longer. We use “weather” to describe shorter‐term, variable atmospheric fluctuations experienced over more restricted areas. We appraise the present state of knowledge and highlight some pitfalls involved in using available information. Cautiously, we suggest future avenues for study, including the possibility of “volcanic winters,” or severe eruption‐induced coolings.
Old maps help interpret Icelandic eruption
Authors: Thórdarsson Thorvaldur , Self Stephen
Published: October 2006

The two maps on the cover show an interesting feature that helps explain one of the mysteries of the 1783–1784 Skaftár Fires fissure basalt eruption. Contemporary reports of the eruption refer to the “east northeastern fires” (fire fountains or other explosive activity), well to the east of the Skaftar Fires crater row. The fires recurred several times between May 1783 and May 1785 (see dates at top of Figure 1). That activity persisted for a little more than a year after the fissure eruption stopped.
A message fron the VGP President
Authors: Brett Robin
Published: October 2006

This message is not of an inspirational nature. I hope that this is a relief to you; if you need inspiration I suggest that you follow the primaries closely in this election year. Instead, I've written a rather dreary piece about the nuts and bolts that keep the Volcanology, Geochemistry, and Petrology (VGP) Section going. These nuts and bolts are essential to the section, however. It may be useful to you, or you may be able to help.

You will be hearing more about the Geophysics Research Forum in the future in these pages. The AGU Council, with your help, will be trying to determine what important issues and priorities should dominate the science over the next few years. Similarly, the National Academy of Sciences—National Research Council's Board on Earth Sciences is planning to write are porton priorities and future opportunities in the Earth sciences. If you have ideas on where you feel the science should be heading, on priorities in the science, on which subfields should be emphasized and which deemphasized, please write me. It's important, as such exercises can profoundly affect the future and future funding of our science. VGP science is particularly exciting, and the best ideas must be included.
Will salt repositories be dry?
Authors: Bredehoeft John D.
Published: October 2006

The National Academy of Science committee that considered geologic disposal of nuclear waste in the mid‐1950s recommended salt as a repository medium, partly because of its high thermal conductivity and because it was believed to be “dry” (perhaps the appropriate thought is “impermeable”). Certainly, the fact that Paleozoic salt deposits exist in many parts of t h e world is evidence for very low rates of dissolution by moving groundwater. The fact that the dissolution rates were so small led many scientists to the conclusion that the salt beds were nearly impermeable. The major source of brine within the salt beds was thought to be fluid inclusions within salt crystals, which could migrate through differential solution toward a source of high heat. The idea that salt was uniformly “dry” was revised when exploratory drilling in the vicinity of the Waste Isolation Pilot Plant (WIPP) in New Mexico encountered brines within the Castile Formation, an evaporite deposit below the Salado Formation. The brine reservoirs were thought to be isolated pockets of brine in an otherwise “impermeable” salt section.
International Geomagnetic Reference Field revision 1987
Authors: Langel R. A.
Published: October 2006

The International Geomagnetic Reference Field (IGRF) is a series of mathematical models of the main geomagnetic field and its secular variation. The models themselves consist of sets of spherical harmonic (or Gauss) coefficients. The IGRF has become a widely used means of deriving values of the geomagnetic field components in, for example, studies of magnetic anomalies a n d investigations of charged particle motions in the ionosphere and the magnetosphere.

Since the adoption of t h e first IGRF (IGRF 1965) by the International Association of Geomagnetism and Aeronomy (IAGA) in 1968 [IAGA Commission 2 Working Group 4, 1969], the IGRF has been revised four times, giving the IGRF 1975 [IAGA Division I Study Group on Geomagnetic Reference Fields, 1975], the third‐generation IGRF [IAGA Division I Working Group 1, 1981], the fourth‐generation IGRF [IAGA Division I Working Group 1, 1985], and the fifth‐generation IGRF which is the subject of this note. Details of the derivation of the original IGRF have been given by Zmuda [1971]; interested readers should see Peddie [1982] and Barraclough [1987] for descriptions of its development up to 1985.
Temperature profiles from Pos Crater Lake
Authors: Neshyba Steve , Fernandez Walter , Diaz‐Andrade José
Published: October 2006

In 1984, we took part in an expedition to measure the temperature field and bathymetry of the acid lake (Figure 1) that has formed in the crater of Poás volcano, Costa Rica, since its last eruption in 1953. Obtaining these data was the first step in a long‐range study planned by researchers at the Center for Geophysical Research, University of Costa Rica (San Jose, Costa Rica), and the College of Oceanography, Oregon State University (Corvallis). The study will eventually consider all aspects of fluid behavior in a volcanic lake that is heated or otherwise convectively driven by energy injected at the lake bottom.

Evidence of convection is clearly visible on the surface of the Poás lake most of the time. Fumarole activity has been continuous since 1953. Phreatic explosions are quite frequent, varying from weak to strong, and the height of the ejected column varies from 1 to more than 500 m. One immediately useful result of the research would be an estimate of the heat transfer from sources within the conduit to the overlying water column. As far as geophysical fluid behavior goes, we are interested in the turbulent and diffusive processes by which heat and chemical species are transferred. We are especially interested in the impact on the density stratification of the density changes that occur as particulates settle downward through the fluid column. The stratification would otherwise be controlled by the turbulent and diffusive processes driven by thermochemical factors.
U.K. reservoir spurs environmental studies
Authors: Cole John A.
Published: October 2006

The South West Water Authority is building a new river regulating reservoir to meet growing demands for water supplies in the Plymouth and Bideford areas of Devon, England. The new reservoir impounds the river Wolf within the Tamar catchment (see figure). The Tamar and its tributaries are prime fishing rivers rich in sea trout and Atlantic salmon. Construction of the Roadford dam began early in 1987, and by 1990 a reservoir capable of storing 37×106 m3 will be created. Releases from the reservoir will regulate the low flows of the river Tamar, from which water will be pumped near its tidal limit at Gunnislake, to water treatment plants supplying Plymouth. Additionally, reservoir water will be pumped over the divide to the river Torridge, thus permitting increased abstraction from the latter catchment.
The Analysis of Extraterrestrial Materials
Authors: Albee Arden L.
Published: October 2006

As implied by its title, this book primarily concerns the actual analysis of extraterrestrial materials (including atmospheres and solar wind) rather than the results of such analyses. Five chapters deal with analysis of these materials in terrestrial laboratories, and six chapters describe remote analysis on spacecraft missions. Most chapters can be easily dated — they were written shortly after the mission, have undergone only sporadic updating, and are largely illustrated by copies of vu‐graphs presented at National Aeronautics and Space Administration (NASA) briefings. This historical approach is quite successful in describing the original lunar receiving laboratory and instruments from specific missions. These chapters bring together good and readable descriptions of instruments from the Surveyor, Apollo, Viking, Pioneer, Venus, and especially the Soviet Lunakhod and Venera missions. The author participated in a number of the investigations involving gamma ray or X ray fluorescence spectrometry, and these sections are especially good. However, the chapters on meteorites, lunar samples, cosmochronology, and reflectance spectroscopy are too dated and should have been completely rewritten to properly convey current research and understanding.
Deep‐ocean seismology seismicity of the northwestern Pacific Basin interior
Authors: Walker Daniel A. , McCreery Charles S.
Published: October 2006

Recordings from a variety of deep‐ocean hydrophone arrays as well as historical accounts and listings of earthquakes from the International Seismological Centre and the National Geophysical Data Center reveal a surprisingly large number of earthquakes from the area of the recently postulated Micronesian subduction zone and from the interior of the Northwestern Pacific Basin, regions generally considered to be aseismic. Unusual patterns of seismicity are observed with lowmagnitude (mb <5.0) earthquakes having epicenters distributed over several hundred kilometers occurring within a few weeks or months of one another. A number of earthquakes within the interior of the Northwestern Pacific Basin are located north and west of Wake Island. Also, the locus of epicenters within the basin suggests a northwest to southeast trending pattern of seismicity. These findings suggest that the world's deep‐ocean basins may be more seismically active than is generally believed, that the distribution of epicenters within the interiors of basins may provide important insights into the stress fields between rising and sinking plate edges, and that efforts should be made to accurately assess the seismicity of ocean interiors.
EPA checks community wells for pesticides
Authors: Wainger Lisa A.
Published: October 2006

The Environmental Protection Agency began testing about 600 community water well systems for pesticides in July. The testing is part of a 2‐year survey of private and community wells throughout the United States designed to identify the extent of pesticide residues in drinking water wells nationwide. Testing on more than 750 private wells began in April.

EPA began the study by examining pesticide use and vulnerability of acquifers for every county in the U.S. including Alaska and Hawaii. Armed with a map of average scores of vulnerability of counties, the study's organizers selected a representative group of counties but weighted the selection toward areas of higher vulnerability and pesticide use. Once the counties were selected, vulnerability within counties was ranked and individual wells were selected. Scientists will be analyzing the water samples from the wells for more than 100 commonly used pesticides in addition to a number of pesticide metabolites, nitrites, and nitrates.
Workshop on the U.S. Antarctic Meteorological Data Delivery System
Authors: Hanson C. S. , Barry R. G. , Stearns C. R.
Published: October 2006

The Polar Coordination and Information Section, Division of Polar Programs, National Science Foundation (DPP/NSF) sponsored a meeting of 28 representatives from organizations that collect, process, transmit, archive, or use meteorological data collected at U.S. Antarctic stations. This workshop, convened by the World Data Center (WDC) A for Glaciology/ National Snow and Ice Data Center (NSIDC) at the University of Colorado at Boulder on September 10–11, 1987, considered the present flow of data from Antarctic stations to the end users. A set of recommendations was drafted and delivered to DPP/ NSF to address problem areas in collecting, archiving, and accessing the data. Charles Steams, University of Wisconsin, Madison, chaired the session, which was organized by Roger Barry, Director of WDC/NSIDC, and Claire Hanson, User Services, WDC/NSIDC.
FROGS (Friends of Granites) Report, summer 1988
Authors: DeYoreo J. J. , Wickham Stephen M. , Miller Calvin
Published: October 2006

This is the second Eos‐published FROGS Report. Our purpose is to disseminate information and stimulate thinking concerning felsic magmatism in general and granitoids in particular. We intend to publish semiannually information about events and publications that are relevant to the study of felsic rocks, brief updates on research being done by granitoid researchers, and commentaries on important new and/or controversial themes. FROGS Reports is critically dependent upon response by those with an interest in research on felsic rocks. Please keep me (Calvin Miller, 6028B, Vanderbilt Univ., Nashville TN 37235) informed about upcoming or recent conferences, major publications, etc. Also, send me your suggestions for topics for (and/or volunteer to write) pertinent commentaries for FROGS Reports.