bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidisciplinary approach yields insight into mt. etna eruption
Authors:   The Research Group of the Instituto Nazionale di Geofisica e Vulcanologia‐Sezione di Catania, Italy
Published: October 2006

On July 17, 2001, lava began pouring down the slopes of Mt. Etna in Sicily signaling the start of the volcano's first flank eruption in nearly 10 years. Etna typically experiences long periods of explosive and effusive activity at the summit, which lies 3350 m a.s.l., interspersed with shorter flank eruptions. During the latter, large volumes of lava can threaten local populations.
The Benthic Boundary Layer: Transport Processes and Biogeochemistry
Authors: van Duren Luca A. , Middelburg Jack J.
Published: October 2006

Interdisciplinary research is certainly one of the current buzzwords that needs to be incorporated in virtually every grant proposal. The idea that integration of different scientific fields is a prerequisite for progress in Earth sciences is now well recognized. The benthic boundary layer (BBL) is one area of research in which physicists, chemists, biologists, geologists, and engineers have worked in close and fruitful cooperation for several decades. The BBL comprises the near‐bottom layer of water, the sediment‐water interface, and the top layer of sediment that is directly influenced by the overlying water. In 1974, a BBL conference in France resulted in a book titled The Benthic Boundary Layer edited by I.N. McCave. This publication contained contributions from scientists from a wide range of disciplines and gave an overview of the state‐of‐the‐art of BBL research. However, science has moved on in the past 25 years. Significant conceptual and technological progress has been made, and it is definitely time for an update.
Researchers target a continental transform fault in Tierra del Fuego
Authors: Lodolo Emanuele , Menichetti M. , Tassone A. , Geletti R. , Sterzai P. , Lippai H. , Hormaechea J.‐L.
Published: October 2006

A comprehensive suite of field surveys was carried out by a team of Italian and Argentinean scientists in South America's Tierra del Fuego region to investigate the 600‐km‐long Magallanes‐Fagnano fault system (MFS), a transform‐type margin that developed on continental crust (Figure 1). Identifying and analyzing the morphological and structural elements related to the MFS and understanding mechanisms of slip along the fault are the principal objectives of an ongoing project called Tectonic Evolution of the South America‐Scotia Plate Boundary During the Cenozoic (TESAC).
Initiative to quantify terrestrial carbon sources and sinks
Authors: Cihlar Josef , Denning Scott , Ahem Frank , Arino Olivier , Belward Alan , Bretherton Francis , Cramer Wolfgang , Dedieu Gerard , Field Christopher , Francey Roger , Gommes Rene , Gosz James , Hibbard Kathy , Igarashi Tamotsu , Kabat Pavel , Olson Dick , Plummer Stephen , Rasool Ichtiaque , Raupach Michael , Scholes Robert , Townshend John , Valentini Riccardo , Wickland Diane
Published: October 2006

Questions related to the distribution and spatio‐temporal dynamics of the terrestrial carbon fluxes are at the core of current scientific and policy debates. In recent years, the primary concern has been the increasing CO2 content in the atmosphere, its effect on climate, and the associated role of terrestrial ecosystems in mitigating the increase and impact of climate change. However, terrestrial carbon dynamics is also closely related to biodiversity land degradation, and other pressing policy and assessment questions. Yet at the global level, no system in place now can provide quantitative information about carbon sources and sinks systematically, reliably, and accurately.
Widespread decline in hydrological monitoring threatens Pan‐Arctic Research
Authors: Shiklomanov A. I. , Lammers R. B. , Vörösmarty C. J.
Published: October 2006

Operational river discharge monitoring is declining in both North America and Eurasia. This problem is especially severe in the Far East of Siberia and the province of Ontario, where 73% and 67% of river gauges were closed between 1986 and 1999, respectively. These reductions will greatly affect our ability to study variations in and alterations to the pan‐Arctic hydrological cycle.
The Solar Mass Ejection Imager (SMEI): A new tool for space weather
Authors: Webb David F. , Johnston Janet C. , Radick Richard R. ,   SMEI Team
Published: October 2006

Later this year, the U.S.Air Force will launch the Solar Mass Ejection Imager (SMEI). SMEI is an instrument that will detect and measure coronal mass ejections (CMEs) which can cause large geomagnetic storms, a major component of space weather. CMEs are very large structures containing plasma and magnetic fields that are expelled from the Sun into the heliosphere at speeds of several hundred to over 1000 km s−1. CMEs often drive interplanetary shock waves which, upon arrival at Earth, can cause geomagnetic disturbances. There is currently no reliable way to accurately predict arrival of these disturbances at Earth or to study them in the inner heliosphere. SMEI is designed to fill this gap by detecting and tracking CMEs in interplanetary space before they reach Earth. SMEI data will be complementary to many other satellite missions and national programs, such as the current National Space Weather and International Solar Terrestrial Programs.
GPS radio occupations coming of age: Spacecraft launches add two new instruments for climate monitoring
Authors: Hajj G. A. , de la Torre Juárez M. , Iijima B. A. , Mannucci A. J. , Yunck T. P.
Published: October 2006

Global Positioning System (GPS) radio occultations are active limb soundings that measure the time delay of a GPS signal propagating through the atmosphere. This time delay can be related to vertical profiles of atmospheric refractivity from which highly accurate profiles of geopotential height, temperature, pressure, and specific humidity are derived. With their global coverage, self‐calibrating nature, penetration through clouds, and high vertical resolution, atmospheric radio occultations are coming of age and hold great promise for weather prediction and climate monitoring.
The last word
Authors: Cliver Edward W. , Cane Hilary V.
Published: October 2006

This is the second in a series of essays on terms used in solar‐terrestrial physics that are thought to be in need of clarification. Terms are identified and essays are commissioned by a committee chartered by Division II (Sun and Heliosphere) of the International Astronomical Union. Terminology Committee members include: Ed Cliver (chair), Jean‐Loius Bougeret, Hilary Cane, Takeo Kosugi, Sara Martin, Rainer Schwenn, Lidia van‐Driel Gesztelyi, and Joe Borovsky (Eos SPA Editor). Writers are asked to review the origins of a given term and its current usage/misusage. The main point is to open a discussion and inform the community. We solicit feedback (to Eos) on the following article by Ed Cliver and Hilary Cane on the use of the terms “impulsive” and “gradual” to describe solar energetic particle events. In addition, we welcome suggestions (to any Committee member) on other terms to address in this forum.
NASA plans Pluto‐Kuiper Belt Mission
Authors: Stern Alan , Cheng Andy
Published: October 2006

The trans‐Neptunian region, which contains the binary planet Pluto‐Charon and the myriad planetary embryos of the Kuiper Belt, is a scientific and intellectual frontier. In recent years, the Pluto‐Charon system has become recognized as a key element for understanding the origin of the outer solar system. So, too, it has become apparent that Pluto‐Charon is a scientific wonderland offering insights into exotic dynamics, the nature of primitive organic material, complex volatile transport processes, and hydrodynamic atmospheric escape, as well as rich surface and atmospheric chemistry. Pluto's size, density albedo, surface composition, and atmosphere also make it a key comparator to Triton, Neptune's large and complex icy satellite.
Workshop explores deep‐Earth structure and metals in the lithosphere
Authors: Kutina Jan , Taylor Patrick T.
Published: October 2006

In 1972, at the 24th International Geological Congress, the International Union of Geological Sciences under the United Nations Educational, Scientific and Cultural Organization (UNESCO) established the International Geological Correlation Program (IGCP). The IGCP was to study the relationship between theoretical and practical geological problems through international cooperation. One of these programs, Economic Super Accumulations of Metals in the Lithosphere, describes relationships between the origin of large concentrations of metals in the crust and deep structure of the lithosphere.
Dive and discover: Expeditions to the seafloor
Authors: Lawrence Lisa Ayers
Published: October 2006

The Dive and Discover Web site is a virtual treasure chest of deep sea science and classroom resources. The goals of Dive and Discover are to engage students, teachers, and the general public in the excitement of ocean disco very through an interactive educational Web site. You can follow scientists on oceanographic research cruises by reading their daily cruise logs, viewing photos and video clips of the discoveries, and even e‐mailing questions to the scientists and crew. WHOI has also included an “Educator's Companion” section with teaching strategies, activities, and assessments, making Dive and Discover an excellent resource for the classroom.
Women exploring the oceans
Authors: Ellins Katherine
Published: October 2006

The new Web site, Remarkable Careers in Oceanography: Women Exploring the Oceans, currently profiles nine women who are making significant contributions to ocean sciences. Funded by the National Science Foundation, the Web site is simply and attractively laid out, without much flash and fuss. This makes it easy to navigate through the different categories that present information about the achievements of the individual women who are profiled, their backgrounds, the science they study, and how they do their work.
Stochastic resonance in glacial climate
Authors: Rahmstorf Stefan , Alley Richard
Published: October 2006

It seems like magic. In an attempt to make it audible, you feed a faint signal, a wave of a particular frequency, through an amplifier—a strange black box that you bought at a junk yard, because your proposal to buy a proper one was turned down once again. Of course you hear nothing. The darn thing doesn't seem to work. Out of sheer destructive frustration, you add some random noise to your signal, and voila! Suddenly you hear it. The noise, rather than blurring your signal, makes it come through loud and clear. Take the noise away and the signal vanishes again.
Ever‐present South Atlantic Anomaly damages spacecraft
Authors: Heirtzler James R. , Allen Joe H. , Wilkinson Daniel C.
Published: October 2006

On 15 June 2001, at 3:56 UT, the Moderate Resolution Imaging Spectroradiometer (MODIS), one of NASAs prime remote sensing instruments on the TERRA spacecraft, was rendered inoperative while on the western flank of the South Atlantic Anomaly (SAA). The SAA is a vaguely‐defined, oval‐shaped geographic region centered roughly off the east coast of Brazil where the Earth's geomagnetic field is relatively weak at all altitudes. Space science and engineering projects have frequently given insufficient attention to the serious problems of working in this geographic area. Here we illustrate that MODIS is just one of many spacecraft that have had problems, and that these problems are expected to get worse.
Landsat imagery shows decline of coastal marshes in Chesapeake and Delaware Bays
Authors: Kearney Michael S. , Rogers Andrew S. , Townshend John R. G. , Rizzo Eric , Stutzer David , Stevenson J. Court , Sundborg Karen
Published: October 2006

Dramatic losses of tidal wetlands in the Mississippi Delta and a few areas along the U.S. Atlantic coast have raised concerns about whether these marshes will survive if global sea level continues to rise due to greenhouse warming [Stevenson et al., 1986]. Original greenhouse warming sea‐level scenarios projected global sea levels several meters or more higher than present by 2100 [Barth and Titus, 1984], which would result in the disappearance of all coastal marshes, as the scarcity of marsh deposits from the rapid transgression during the middle Holocene testifies [Rampino and Sanders, 1981]. However, more recent estimates of global sealevel change suggest that some coastal marshes could survive [Douglas et al., 2000].
Surfactant‐modified zeolite can protect drinking water wells from viruses and bacteria
Authors: Schulze‐Makuch Dirk , Pillai Suresh D. , Guan Huade , Bowman Robert , Couroux Emile , Hielscher Frank , Totten James , Espinosa Isabell Y. , Kretzschmar Thomas
Published: October 2006

Septic tanks, sewage effluents, and landfills can release microbial pathogens into groundwater. This problem is amplified in the so‐called colonias along the U.S.‐Mexico border and other low‐income areas around the world that have no public sewage systems. The result is often outbreaks of groundwater‐associated disease for which enteric viruses and bacteria, spread via a fecal‐oral route, are responsible. However, due to difficulties and limitations in detection and surveillance of disease outbreaks, the causative agents for more than 50% of the outbreaks are unknown, though the clinical features suggest a viral etiology for most of those cases [U.S. Centers for Disease Control and Prevention, 1993]. Enteric pathogens such as E coli 0157:H7, Campylobacter, Enteroviruses, Hepatitis A virus, and caliciviruses have been responsible for groundwater‐related microbial infections in humans. Inexpensive solutions to this problem are urgently needed. The recent threat of bio‐terrorism and concerns about the safety of drinking water supplies further add to that urgency.
Enhanced oceanic and atmospheric monitoring underway in eastern Pacific
Authors: Cronin Meghan F. , Bond Nicholas , Fairall Chris , Hare Jeffrey , McPhaden Michael J. , Weller Robert A.
Published: October 2006

The Eastern Pacific Investigation of Climate Processes (EPIC) is a 5‐year experiment designed to improve our understanding of the inter‐tropical convergence zone (ITCZ), its interaction with the cool water that upwells along the equator in the eastern Pacific, and the physics of the stratus cloud deck that forms over the cool waters off South America. EPIC fieldwork began in 1999, and involves shortterm process studies embedded within longerterm (3–4 years) enhanced monitoring built on the El Niño‐Southern Oscillation (ENSO) observing system. The enhanced monitoring portion of the experiment is about half‐way complete and is already providing interesting new results on the workings of the eastern Pacific stratus deck/cold tongue/ITCZ complex.
Did the Italian Government approve an obsolete project to save Venice?
Authors: Pirazzoli Paolo Antonio
Published: October 2006

The government of Silvio Berlusconi of Italy decided on 6 December 2001, to move forward with a project called the Experimental Electromechanical Module (MOSE) for mobile flood barriers at the inlets of the lagoon of Venice to protect the city from storm surges. This project is not only much debated for its environmental impacts, but it could also become rapidly obsolete in the event of a near‐future sea‐level rise.

The Experimental Electromechanical Module project consists of 79 mobile gates at the three inlets to the lagoon. These will be closed when the tide height threatens to reach the level of 1.10 m above the mean sea level (MSL) of the period 1884–1909; that is, about 0.87 m above present MSL. The 20‐m‐long gates will lie on the floor of the lagoon inlets in normal times, but can be raised to partially seal the openings by injecting compressed air.
Arctic‐CHAMP:A program to study arctic hydrology and its role in global change
Authors: Vörösmarty Charles , Hinzman Larry , Peterson Bruce , Bromwich David , Hamilton Lawrence , Morison James , Romanovsky Vladimir , Sturm Matthew , Webb Robert
Published: October 2006

The Arctic constitutes a unique and important environment that is central to the dynamics and evolution of the Earth system. The Arctic water cycle, which controls countless physical, chemical, and biotic processes, is also unique and important. These processes, in turn, regulate the climate, habitat, and natural resources that are of great importance to both native and industrial societies. Comprehensive understanding of water cycling across the Arctic and its linkage to global biogeophysical dynamics is a scientific as well as strategic policy imperative.
Combined technologies allow rapid analysis of glacier changes
Authors: Paul Frank
Published: October 2006

Monitoring of glacier changes plays an important role within the Global Climate Observing System (GCOS) [Haeberli et al., 2000] and Landsat imagery has proven to be a useful tool for monitoring glacier changes over large and remote areas [Aniya et al., 1996; Li et al., 1998]. An accurate glacier map can be obtained by simple segmentation of a ratio image from Thematic Mapper (TM) channels 4 and 5 [Bayr et al., 1994, Jacobs et al., 1997; Paul, 2002] Individual glaciers were recently derived within a Geographic Information System (GIS) using a vector layer with glacier basin boundaries. Glacier changes were calculated and visualized by processing sequential images within a fully automated work flow.
Chelungpu fault drilling could resolve seismological issues
Authors: Mori James , Ito Hisao , Wang Chien‐Ying
Published: October 2006

The 1999 Mw 7.7 Chi‐chi earthquake in Taiwan produced spectacular surface faulting, with vertical displacements of up to 8 m on the Chelungpu fault. The large amount of fault slip at or near the surface provides a unique opportunity to study first‐hand the physical mechanisms involved in faulting during large earthquakes. Intriguingly the portions of the fault in the north that had the largest amount of displacement produced relatively low levels of damage. The slip and slip velocity were very large, but the high‐frequency acceleration was relatively low, suggesting that somehow the northern portion of the fault slipped rather smoothly

This clearly‐recorded behavior of the Chleungpu fault provides clues for unraveling an important research topic in seismology: What physical properties or dynamic processes control the distribution of large slip during an earthquake? It is well known that the amount of slip during a large earthquake varies considerably at different locations along the fault. However, little is known about why this is so. Understanding what controls the amount of slip that occurs on the fault would improve our understanding of the earthquake rupture process.
Probing the mantle: The story from carbonatites
Authors: Bell Keith , Tilton George R.
Published: October 2006

One of the most exciting advances in Earth science in the last several decades has been our increased understanding of the structure and composition of the mantle. Seismic tomography and isotope geochemistry have been major players in those advances. The isotopic studies used basalts from ocean basins to minimize the problems of possible crustal contamination. Data from mid‐ocean ridge basalts (MORBs) and oceanic island basalts (OIBs) revealed a relatively detailed picture of the isotope geochemistry of the sub‐oceanic mantle [e.g. Hofmann, 1997] that led to the recognition of four principal magma components that define end‐member compositions. These are DMM, HIMU, EMI, and EM2 (see Table 1 for further details). All of these components except DMM have been attributed to subduction of different materials, such as oceanic and continental crust and lithosphere, down into the mantle. Several studies have indicated that the mantle is isotopically heterogeneous with heterogeneities that were probably established at least several billions of years ago.
Recent sediment studies refute Glen Canyon Dam Hypothesis
Authors: Rubin David M. , Topping David J. , Schmidt John C. , Hazel Joe , Kaplinski Matt , Melis Theodore S.
Published: October 2006

Recent studies of sedimentology hydrology, and geomorphology indicate that releases from Glen Canyon Dam are continuing to erode sandbars and beaches in the Colorado River in Grand Canyon National Park, despite attempts to restore these resources. The current strategy for dam operations is based on the hypothesis that sand supplied by tributaries of the Colorado River downstream from the dam will accumulate in the channel during normal dam operations and remain available for restoration floods. Recent work has shown that this hypothesis is false, and that tributary sand inputs are exported downstream rapidly typically within weeks or months under the current flow regime.
Satellite images track “black water” event off Florida Coast
Authors:   South‐West Florida Dark‐Water Observations Group (SWFDOG)
Published: October 2006

A mass of dark water, at times exceeding 60 km in diameter and spinning slowly in a clockwise eddy, occupied most of the Florida Bight between January and March 2002, capturing the attention of fishermen, the public, and government agencies. The “black water,” as it was dubbed in the national and international press (for example, see http://www.naplesnews.com), was first reported by fishery pilots in the Florida Bight in January 2002. Fishermen reported that fish were not to be found in the black water and there were dead sponges in the vicinity, suggesting that the area could be a “dead zone” similar to the one found every summer off the Louisiana coast.
Lidar studies of atmospheric dynamics near polar mesopause
Authors: She C. Y. , Vance Joe D. , Williams B. P. , Krueger David A. , Moosmüller Hans , Gibson‐Wilde Dorothy , Fritts Dave
Published: October 2006

Global change, space weather, and their possible adverse impacts on human activities are not only of scientific interest, but also of great public concern. Since the Arctic middle and upper atmosphere exhibits significant sensitivity to internal and external perturbations, systematic studies at high latitudes have become a scientific priority.

Several international research programs are being conducted at the Arctic Light Detection and Ranging Observatory for Middle Atmosphere Research (ALOMAR), which was established at Andøya, Norway (69°N, 16°E) in 1994 to perform regular Arctic light detection and ranging (lidar) observations in tandem with other radio and optical instrumentation, as well as with in situ rocket and balloon measurements [von Zahn, 1997].
Survey tracks current position of South Magnetic Pole
Authors: Barton Charles
Published: October 2006

The search for the Earth's magnetic dip poles—the principal points on the surface where the geomagnetic field is vertical—was driven initially by a combination of adventurism and the need for magnetic compass correction information for navigation. The position and drift of the magnetic poles remain topics of popular interest today and are of scientific value; e.g., for testing the accuracy of global field models in polar regions. The South Magnetic Pole, first reached in January 1909 by Edgeworth David, Douglas Mawson, and Alistair Mackay during an epic man‐hauled sledge journey onto the interior of the Antarctic Plateau, drifted out to sea in about 1960.
Silicic volcanism and hydrothermal activity documented at Pacific‐Antarctic Ridge
Authors: Stoffers Peter , Worthington T. , Hekinian R. , Petersen S. , Hannington M. , Türkay M. ,   SO 157 Shipboard Scientific Party
Published: October 2006

How well do we know the composition of oceanic crust? Countless studies have described the occurrence of mid‐ocean ridge basalt (MORB) at spreading centers, and few would argue that the bulk composition of oceanic crust is other than basaltic. Nevertheless, silicic volcanism (>55 wt.% SiO2) does occur along part of the northern East Pacific Rise (10.5°N; Thompson et al. [1989]),on the 095° propagator of the Galápagos Spreading Center [Clague et al., 1981],and was recently discovered on the Pacific‐Antarctic Ridge (PAR) near its intersection with the Foundation seamount chain [Hekinian et al., 1997, 1999]. Silicic lavas were recovered from a 290‐km‐long section of the northern PAR adjacent to the active Foundation plume (Figure 1) during cruise 157 of the F/S Sonne, which took place in June and July 2001. Furthermore, widespread hydrothermal activity indicates that the volcanogenic massive sulfidesilicic lava association is not only restricted to subduction and back arc settings.
Improved estimates of coastal population and exposure to hazards released
Authors: Nicholls Robert J. , Small Christopher
Published: October 2006

Though it is well known that the world's coastlines are heavily populated, the combined implications of population growth and climate change are still subject to debate. Models of hazard impact, adaptation, and vulnerability stress the importance of understanding both exposure and adaptive capacity of the threatened systems [e.g.,Smit et al., 2001]. Combining geophysical and socio‐economic data sets can greatly improve our understanding of exposure at a range of scales from local to global.

Here we estimate an upper bound on the global exposure to coastal hazards based on 1990 population distribution. The focus is on exposure to natural hazards, but these estimates also provide an indication of the direct human pressure on the coastal zone. Data from 1990 were used, as this global population distribution was the most robust currently available.
Ocean bottom seismometers deployed in Tyrrhenian Sea
Authors: Dahm Torsten , Thorwart M. , Flueh E. R. , Braun Th. , Herber R. , Favali P. , Beranzoli L. , D'Anna G. , Frugoni F. , Smriglio G.
Published: October 2006

The Institute for Geophysics (IfG) at Hamburg University and the Research Center for Marine Geoscience (GEOMAR) of Kiel University have developed new, wideband ocean bottom seismic stations (OBS) for long‐term, deep‐sea deployments of up to 1 year. A first long‐term pilot experiment of these stations was conducted in the Tyrrhenian Sea north of Sicily, in‐cooperation with the first long‐term, deep‐sea test of the European Ocean Bottom Observatory GEOSTAR [Beranzoli et al., 2000] by Istituto Nazionale di Geofisica e Vulcanologia (INGV). The seismic data retrieved prove that the new OBSs are useful for seismological studies. A large number of tele‐seismic earthquakes have been recorded in good quality; waves originating from such events pass the mantle and crust below the network, and thus provide important constraints on their structure.
HoPE receives the 2002 Excellence in Geophysical Education Award
Authors: Duba Al ,   American Museum of Natural History's HoPE Team
Published: October 2006

“A little over a year ago, I decided to nominate the American Museum of Natural History's Hall of Planet Earth (HoPE) for the AGU Excellence in Geophysical Education Award.”

“I took this step with some trepidation, knowing that I had some conflict of interest, having just started to work there on leave from LLNL. However, I had taken the job because of the opportunity to communicate my science to the general public, and I was inordinately pleased with the many opportunities that abounded, thanks to the hard work and foresight of the people who had built HoPE. So when Deane Rink suggested we nominate HoPE for this award, I decided to go for it, nominating the four people most responsible for putting it all together: Ed Mathez, Heather Sloan, Jim Webster, and Ro Kinzler.
Forecasting system predicts presence of sea nettles in Chesapeake Bay
Authors: Brown Christopher W. , Hood Raleigh R. , Li Zhen , Decker Mary Beth , Gross Thomas F. , Purcell Jennifer E. , Wang Harry V.
Published: October 2006

Outbreaks of noxious biota, which occur in both aquatic and terrestrial systems, can have considerable negative economic impacts. For example, an increasing frequency of harmful algal blooms worldwide has negatively affected the tourism industry in many regions. Such impacts could be mitigated if the conditions that give rise to these outbreaks were known and could be monitored. Recent advances in technology and communications allow us to continuously measure and model many environmental factors that are responsible for outbreaks of certain noxious organisms. A new prototype ecological forecasting system predicts the likelihood of occurrence of the sea nettle (Chrysaora quinquecirrha), a stinging jellyfish, in the Chesapeake Bay.
El Niño‐induced flooding in the U.S. West: What can we expect?
Authors: Pizarro Gonzalo , Lall Upmanu
Published: October 2006

Ocean conditions in the tropical Pacific seem to be signaling the emergence of another El Niño event. Even though it is uncertain what will happen in the next two to three seasons, climate forecasting centers are beginning to advise planners in ENSO‐sensitive regions to review their contingency plans. Here, we examine the potential for floods in the western United States as measured by the annual maximum flood in the region.

The timing (figure 1) and causes of the annual maximum flood vary across the western United States. Nevertheless, correlations of the annual maximum flood with January‐April averages of the NIN03 and Pacific Decadal Oscillation (PDO) indices are statistically significant over large, contiguous areas in the region, irrespective of the dominant season of occurrence and the operative climate mechanism.
New generation mooring system allows longer deployment
Authors: Frye Dan , Hogg Nelson , Wunsch Carl
Published: October 2006

Conventional mooring systems in use today are mainly derived from technology that was developed from the 1950s through the 1970s. The subsurface or “intermediate” mooring design that matured in the 1970s allows measurements to be made reliably for up to 2 years. Thousands of these moorings have been deployed throughout the world's oceans and most marginal seas. A partial archive of the data that have been collected is available at http://ortelius.whoi.edu/website/BGTS/viewer.htm. Much of what we have learned about ocean circulation, and the processes governing it, has been provided by the world‐wide effort to acquire moored (Eulerian) measurements of temperature, velocity, and other associated time series.
Progress made in study of ocean's calcium carbonate budget
Authors: Iglesias‐Rodriguez M. Debora , Armstrong Robert , Feely Richard , Hood Raleigh , Kleypas Joan , Milliman John D. , Sabine Christopher , Sarmiento Jorge
Published: October 2006

Many of the uncertainties in diagnostic and prognostic marine carbon cycle models arise from an imperfect understanding of the processes that control the formation and dissolution of calcium carbonate (CaCO3). On the production side of the equation, the factors that control the abundances of calcifying phytoplankton or zooplankton are largely unknown. On the dissolution side, changes in the depth of CaCO3 saturation horizons for both calcite and aragonite may produce large‐scale changes in dissolution of shelf and slope sediments and reefs, with potentially significant implications for atmospheric carbon dioxide concentration and climate change, as well as for coralline organisms themselves.

In recent years, concern about the long‐term fate of anthropogenic CO2 in the oceans has re‐ignited scientific interest in the fundamental abiotic and biotic processes that control the marine CaCO3 budget, since biological CaCO3 production and export are important mechanisms by which carbon is exported from the ocean's surface to its abyss. CaCO3 precipitation releases CO2 to solution, while CaCO3 dissolution takes up CO2 from solution.
Recent acceleration of the north magnetic pole linked to magnetic jerks
Authors: Newitt L. R. , Mandea M. , McKee L. A. , Orgeval J.‐J.
Published: October 2006

Surveys to determine the location of the North Magnetic Pole (NMP) have been conducted regularly since 1947 to serve two basic functions: to educate, and to provide valuable research. The public has always been fascinated and often misinformed about the nature and significance of the NMP. Thus, an NMP survey offers an ideal opportunity for public outreach and education. Scientifically, NMP surveys test the veracity of global magnetic field models such as the International Geomagnetic Reference Field. The act of determining the NMP's position also reveals facts about its motion that might otherwise be overlooked when using global models. The most recent survey of the NMR completed in May 2001, showed an unprecedented increase in the pole's rate of motion.
Reply [to “Comment on ‘Assessing flood hazard on dynamic rivers’”]
Authors: Pinter Nicholas , Thomas Russell , Wlosinski Joseph H.
Published: October 2006

We welcome the comments by D. M. Goldman, J. R. Olsen, and S. K. Nanda of the U.S. Army Corps of Engineers on our analyses of flood trends on the Middle Mississippi River (MMR) and on our assertion that historical stage data can be utilized in flood‐frequency analysis. In some cases, the comments by the Corps authors point out legitimate limitations in the technique presented in our original article—limitations that we also have pointed out (for example, to funding agencies) as directions for future refinement. In other cases, Goldman et al. repeat arguments that have been used for decades to stymie attempts to link river engineering activities to worsening flood behavior. We welcome the opportunity to review these arguments under the spotlight of rigorous analysis. Finally, a major purpose of the Pinter et al. [2001] paper was to show that historical stage data represent an underutilized resource that has promise as a supplement to, and an independent test of discharge‐based, model‐driven analyses of flood frequency.
Broadband seismic experiments probe the East African Rift
Authors: Nyblade Andrew A. , Langston Charles A.
Published: October 2006

To further advance our understanding of how and why continents rift apart, the upper mantle structure beneath east Africa is being investigated by three Incorporated Research Institutes of Seismology/Program for the Array Seismic Studies of the Continental Lithosphere (IRIS/PASSCAL) broadband seismic experiments. The origin of Cenozoic rifting in east Africa, along with the volcanism and plateau uplift found there, has long fascinated Earth scientists. The rift system can be linked to extensional stresses associated with the development of the Afar triple junction, but it is unlikely that the small amount of crustal extension, ≤10–15 km, across east Africa could have led to sufficient pressure‐release melting to account for the large volume of extrusive rock present in some parts of the rift system, or enough thinning of the lithosphere to cause plateau uplift ≥1 km. Consequently, a purely “passive” origin for the Cenozoic extensional tectonism has been frequently rejected. Instead, it has been commonly attributed to one or more mantle plumes, a view supported strongly by geochemical evidence. However, non‐plume models cannot be ruled out completely, based on existing observations of mantle structure and composition, nor is it clear how many plumes might be present beneath east Africa.
The Newcomb‐Michelson velocity of light experiments
Authors: Carter Wiiliam E. , Carter Merri Sue
Published: October 2006

In 1877, at age 42, Simon Newcomb became the superintendent of the Nautical Almanac Office (NAO), U.S. Naval Observatory in Washington D.C. That same year, at age 25, Ensign Albert Michelson began his new assignment as a professor of physics and chemistry at the U.S. Naval Academy in Annapolis, Maryland [Reingold, 1964]. While they worked for the same agency less than 1 hour apart by train, the two men lived in very different worlds. Newcomb had already achieved international acclaim for his studies of the orbits of Neptune and Uranus and had his choice of any number of prestigious and powerful positions at scientific institutions and astronomic observatories throughout the nation. As a junior naval officer Michelson could, at best, expect to spend a few years teaching at the Naval Academy before being reassigned to sea duty. Within 2 years of graduating, Michelson had already served aboard five ships of the line, sailing to ports as distant as Rio de Janeiro [Livingston, 1973]. Newcomb had direct access to the secretary of the Navy and members of Congress, and when he learned that Michelson had begun to work on velocity of light experiments, he did not hesitate in having the young ensign detailed to the Naval Observatory. Together they assembled and perfected an apparatus that measured the velocity of light more accurately than had ever been possible before, and the value obtained from the complete set of experiments performed in Washington—299,810 km/s—was not bettered for more than 4 decades.
Maps and animations offer new opportunities for studying the global water cycle
Authors: Birks S. J. , Gibson J. J. , Gourcy L. , Aggarwal P. K. , Edwards T. W. D.
Published: October 2006

The International Atomic Energy Agency/World Meteorological Organization Global Network for Isotopes in Precipitation (IAEA/WMO GNIP) data base includes more than 100,000 δ18O,δ2H, and 3H measurements performed on monthly precipitation samples collected at 550 stations worldwide. Since 1961, the data base has served as a baseline reference for the distribution of water isotopes in modern precipitation. It is widely used in the fields of isotope hydrology, climatology oceanography and paleoclimatology.
Comparison of palaeoclimate simulations enhances confidence in models
Authors: Harrison Sandy P. , Braconnot Pascale , Joussaume Sylvie , Hewitt Chris , Stouffer Ronald J.
Published: October 2006

The Paleoclimate Modelling Intercomparison Project (PMIP) [Joussaume and Taylor, 2000] is an international project involving members of all major climate modeling groups worldwide. Endorsed by the World Climate Research Programme (WCRP) and the International Geosphere‐Biosphere Programme (IGBP), PMIP was launched in 1994 to provide a framework for evaluating climate models. By examining climate change that occurred when the external forcings were large and relatively well known and for which geological evidence exists, PMIP plans to determine the models' ability to reproduce climate states that are radically different from those of today
Seismic experiments target earthquake‐prone region in Romania
Authors: Hauser F. , Prodehl C. , Landes M. ,   VRANCEA working group
Published: October 2006

Several major earthquakes struck Romania in the last century, and all of them occurred in the Vrancea zone in the southeast Carpathian Mountains (Figure l). These earthquakes claimed many lives and caused extensive damage. In the 1977 earthquake alone, 1,570 people died and more than 11,300 were injured, 32,900 apartments were completely destroyed or severely damaged, and economic loss was estimated at more than $2 billion.

To study the crustal and uppermost mantle structure beneath this seismic high‐risk area, two major active‐source seismic experiments were carried out in 1999 and 2001, nearly 30 years after the last seismic investigations across the eastern Carpathians in the 1970s. The joint seismic refraction and reflection field effort conducted in August and September 2001 (Figure 1), which used almost 800 stand‐alone recorders, is one example of the productive interaction forged during the 1999 experiment [Hauser et al., 2001].
Is the number of Antarctic icebergs really increasing?
Authors: Long David G. , Ballantyn Jarom , Bertoia Cheryl
Published: October 2006

Icebergs released from the ice shelves and glaciers of Antarctica account for the majority of the continent's freshwater flux into the ocean. It is estimated that an average of nearly 2000 km3 [Jacobs et al., 1992] of ice are released from continental ice shelves and glaciers each year. Much of this ice is released in the form of very large icebergs, some of which are as large as 295 km×37 km.

A recent article by Bindschadler and Rignot [2001] notes that the number of icebergs around Antarctica appears to be on the rise, potentially heralding a climate trend. Examination of the National Ice Center (NIC) Antarctic iceberg data base tends to support the observation of an increase in the number of icebergs. Further driving the concern is the size of recently calves icebergs such as the largest ever observed, B15 measuring 295 km×37 km, which calved from the Ross Ice Shelf in March 2000.
Laser Raman spectroscopy used to study the ocean at 3600‐m depth
Authors: Brewer Peter G. , Pasteris Jill , Malby George , Peltzer Edward , White Sheri , Freeman John , Wopenka Brigitte , Brown Mark , Cline Danelle
Published: October 2006

Making geochemical measurements in the deep ocean is fundamentally difficult. For this reason, century‐old technologies using water bottles and cores for sample recovery still provide the basic tools. With the development of research submersibles and remotely operated vehicles (ROVs), however, new opportunities for sophisticated sampling and analysis have arisen.
Past deep‐ocean circulation and the paleoclimate record‐Gulf of Cadiz
Authors: Mulder T. , Lecroart T. P. , Voisset M. , Schönfeld J. , Le Drezen E. , Gonthier E. , Hanquiez V. , Zahn R. , Faugères J.‐C. , Hernandez‐Molina F. J. , Llave‐Barranco E. , Gervais A. ,   CADISAR and IMAGES V‐GINNA scientific teams
Published: October 2006

Deep marine currents are strongly influenced by climatic changes. They also deposit, rework, and sort sediment, and can generate kilometer‐scale sedimentary bodies (drifts). These drifts are made of thoroughly bioturbated, stacked sedimentary sequences called contourites [Gonthier et al., 1984]. As a consequence, change in the direction or intensity of currents can be recorded in the sediments.
Extending the ice core record beyond half a million years
Authors:   The EPICA Dome C 2001‐02 Science and Drilling Teams
Published: October 2006

Ice cores have been a crucial source of information about past changes in the climate and atmosphere. The Vostok ice core from Antarctica has provided key global change data sets extending 400,000 years in the past [Petit et al., 1999], while Japanese scientists drilling at Dome Fuji have obtained records extending to 330,000 years. Now, a new core being drilled by a consortium of European laboratories has surpassed these ages, and looks like extending the ice core record several hundred thousand years into the past.

Ice cores are unique: of all the paleo‐records, they have the most direct linkage with the atmosphere. At some sites, the time resolution is sufficient to study extremely fast climate changes; and they have information about many forcing factors for climate (including greenhouse gas concentrations) displayed in the same cores as the resulting climate changes.
Methane Hydrates in Quaternary Climate Change: The Clathrate Gun Hypothesis
Authors: Anonymous
Published: October 2006

A new AGU title, Methane Hydrates in Quaternary Climate Change: The Clathrate Gun Hypothesis, by James P. Kennett, Kevin G. Cannariato, Ingrid L. Hendy and Richard J. Behl, presents an alternate hypothesis to explain climate behavior, including abrupt warming over the past 800,000 years. According to the Clathrate Gun Hypothesis, periodic releases of atmospheric methane from melting methane hydrate amplified a pattern of temperature fluctuations and triggered “greenhouse” warming that led to an increase in global temperatures.
Reconstructing “background” Rates of sea‐level rise as a tool for forecasting coastal wetland loss, Mississippi Delta
Authors: Törnqvist Torbjörn E. , González Juan L. , Newsom Lee A. , van der Borg Klaas , de Jong Arie F.M.
Published: October 2006

The Mississippi Delta is one of the most vulnerable coastal regions in the world, with rapidly deteriorating wetlands and an increasing threat for the city of New Orleans due to accelerated relative sea‐level (RSL) rise. Rational coastal forecasting and policy‐making for this area requires a detailed understanding of the temporal and spatial dimensions of RSL change. However, considerable controversy currently exists about the nature of Holocene RSL rise along the Gulf Coast. We have collected new, high‐resolution RSL data from the eastern part of the Mississippi Delta that show that this area experienced smooth and continuous RSL rise that gradually decreased during the Holocene, consistent with numerous observations worldwide. Here, we demonstrate the potential of such data for quantifying natural “background” rates of RSL rise that should be taken into account in coastal forecasting of such threatened environments.
World droughts in the new millennium from AVHRR‐based vegetation health indices
Authors: Kogan Felix
Published: October 2006

The new millennium has started with a series of large‐area droughts which have had grim consequences for the affected countries and regions. The enormous impacts of the 2000 and 2001 droughts were experienced on both physical and psychological levels, in part because no large‐scale drought occurred in 1999. In some regions, severe drought continued for two years in a row.
Listening to the secret sounds of Earth's atmosphere
Authors: Headlin Michael A. H. , Garces Milton , Bass Hank , Hayward Chris , Herrin Gene , Olson John , Wilson Charles
Published: October 2006

A new global network is breathing life into a dormant branch of geophysics. The study of infrasound, or long‐period acoustic signals in the atmosphere was bustling in the 1950s and 1960s. Prior to 1963, almost all nuclear tests occurred in the atmosphere. After 1963, the USSR and U.S. signed the Limited Test Ban Treaty (LTBT), which eliminated all atmospheric nuclear tests. During the era of atmospheric nuclear testing, infrasound research was in demand, since the massive explosions produced strong, long‐period acoustic waves that were globally observed and could be used to locate and describe the nuclear tests. Interest in this branch of geophysics waned with the end of atmospheric testing.
Refining our understanding of oceanic biogeochemistry and ecosystem functioning
Authors: Showstack Randy
Published: October 2006

On societally relevant time scales (e.g., decades to centuries), oceanic biological processes sequester large quantities of atmospheric carbon, thereby modulating C02 concentrations in the lower atmosphere [IPCC, 2001]. The complex physical and biogeochemical interactions that regulate carbon fluxes between the atmosphere and the surface ocean— apparently random physical events, fluctuations in community structure and function, natural climate cycles, and long‐term changes in anthropogenic forcing—are best studied within the framework of ocean time‐series observations. Such thinking led in 1988 to the initiation of the U.S. JGOFS (Joint Global Ocean Flux Study) time‐series programs in the subtropical North Atlantic (BATS = Bermuda Atlantic Time‐series Study) and North Pacific (HOT = Hawaii Ocean Time‐series), and motivates continuing observations into the foreseeable future. After 14 years of intensive physical, biological, and biogeochemical sampling in these regions, the paradigms that initially guided our understanding and research of ocean ecosystems have been found wanting, and new perspectives have emerged to provide a stimulating foundation for continued investigations.
Asher P. Schick (1931–2002)
Authors: Hassan Marwan A. , Laronne Jonathan B.
Published: October 2006

On 15 July 2002, Asher PSchick passed away from cancer at his home in Motza Illit. Schick, a pioneer in arid‐zone fluvial geomorphology was a professor at the Hebrew University in Jerusalem. He began his career when fluvial geomorphology was dominantly a descriptive science, and reliance on geophysical theory and field measurements was a relatively new concept. Schick became a member of AGU (Hydrology) in 1995.