bluuebunny/crossref_metadata_2025 huggingface dataset:
The mode of deformation in the orogenic mid‐crust revealed by seismic attribute analysis
Authors: Torvela Taija , Moreau Julien , Butler Robert W. H. , Korja Annakaisa , Heikkinen Pekka
Published: February 2013

The processes and the structures within the middle and the lower crust are intimately related to the evolution of orogenies, but more detailed knowledge is needed of these deep crustal processes. Seismic reflection data, chiefly displayed in amplitude, are commonly used to interpret deep crustal structures. The strongest amplitude events are probably related to lithological changes and do not necessarily correspond to geological structures, tectonic boundaries, or deformation fabrics. Furthermore, the detailed structures and the strain distribution between the interpreted structural boundaries remain obscure. Here, we show an example of how seismic attributes, combined with the seismic facies interpretation technique, can be used to enhance 2D seismic reflection data from the Palaeoproterozoic Svecofennian crust of southern Finland, to reveal unprecedentedly detailed information about the deformation fabrics within the mid‐crust of a collisional orogen. The images are plausibly interpreted to show that the extension/lateral flow of the orogenic middle and lower crust was mainly accommodated by kilometer‐scale S‐C′ structures. The structures form penetrative deformation fabrics which are correlated with outcrop observations. The successful enhancement of the seismic data confirms the ductile extension affecting hot orogenic crust, and gives new information about the strain distribution of the regional, syn‐ to late‐orogenic deformation. The seismic attribute method and the seismic facies interpretational approach described in this paper should be applicable to other seismic datasets from the crystalline basement.
In situ stress and pore pressure in the Kumano Forearc Basin, offshore SW Honshu from downhole measurements during riser drilling
Authors: Saffer D. M. , Flemings P. B. , Boutt D. , Doan M.‐L. , Ito T. , McNeill L. , Byrne T. , Conin M. , Lin W. , Kano Y. , Araki E. , Eguchi N. , Toczko S.
Published: February 2013

In situ stress and pore pressure are key parameters governing rock deformation, yet direct measurements of these quantities are rare. During Integrated Ocean Drilling Program (IODP) Expedition #319, we drilled through a forearc basin at the Nankai subduction zone and into the underlying accretionary prism. We used the Modular Formation Dynamics Tester tool (MDT) for the first time in IODP to measure in situ minimum stress, pore pressure, and permeability at 11 depths between 729.9 and 1533.9 mbsf. Leak‐off testing at 708.6 mbsf conducted as part of drilling operations provided a second measurement of minimum stress. The MDT campaign included nine single‐probe (SP) tests to measure permeability and in situ pore pressure and two dual‐packer (DP) tests to measure minimum principal stress. Permeabilities defined from the SP tests range from 6.53 × 10−17 to 4.23 × 10−14 m2. Pore fluid pressures are near hydrostatic throughout the section despite rapid sedimentation. This is consistent with the measured hydraulic diffusivity of the sediments and suggests that the forearc basin should not trap overpressures within the upper plate of the subduction zone. Minimum principal stresses are consistently lower than the vertical stress. We estimate the maximum horizontal stress from wellbore failures at the leak‐off test and shallow MDT DP test depths. The results indicate a normal or strike‐slip stress regime, consistent with the observation of abundant active normal faults in the seaward‐most part of the basin, and a general decrease in fault activity in the vicinity of Site C0009.
Timing, origin and emplacement dynamics of mass flows offshore of SE Montserrat in the last 110 ka: Implications for landslide and tsunami hazards, eruption history, and volcanic island evolution
Authors: Trofimovs J. , Talling P. J. , Fisher J. K. , Sparks R. S. J. , Watt S. F. L. , Hart M. B. , Smart C. W. , Le Friant A. , Cassidy M. , Moreton S. G. , Leng M. J.
Published: February 2013

Mass flows on volcanic islands generated by volcanic lava dome collapse and by larger‐volume flank collapse can be highly dangerous locally and may generate tsunamis that threaten a wider area. It is therefore important to understand their frequency, emplacement dynamics, and relationship to volcanic eruption cycles. The best record of mass flow on volcanic islands may be found offshore, where most material is deposited and where intervening hemipelagic sediment aids dating. Here we analyze what is arguably the most comprehensive sediment core data set collected offshore from a volcanic island. The cores are located southeast of Montserrat, on which the Soufriere Hills volcano has been erupting since 1995. The cores provide a record of mass flow events during the last 110 thousand years. Older mass flow deposits differ significantly from those generated by the repeated lava dome collapses observed since 1995. The oldest mass flow deposit originated through collapse of the basaltic South Soufriere Hills at 103–110 ka, some 20–30 ka after eruptions formed this volcanic center. A ~1.8 km3 blocky debris avalanche deposit that extends from a chute in the island shelf records a particularly deep‐seated failure. It likely formed from a collapse of almost equal amounts of volcanic edifice and coeval carbonate shelf, emplacing a mixed bioclastic‐andesitic turbidite in a complex series of stages. This study illustrates how volcanic island growth and collapse involved extensive, large‐volume submarine mass flows with highly variable composition. Runout turbidites indicate that mass flows are emplaced either in multiple stages or as single events.
The large‐scale surface uplift in the Altiplano‐Puna region of Bolivia: A parametric study of source characteristics and crustal rheology using finite element analysis
Authors: Hickey James , Gottsmann Joachim , del Potro Rodrigo
Published: February 2013

This paper focuses on the driving mechanism behind a 70 km wide region of ground uplift centered on Uturuncu volcano, in the Altiplano‐Puna region of southern Bolivia. We present a series of forward models using finite element analysis to simultaneously test for first‐order parameters that help constrain a viable model for the observed maximum line of sight uplift rate of 1–2 cm/yr between 1992 and 2006. Stresses from pressure sources with finite geometries are solved numerically, accounting for both homogeneous and heterogeneous mechanical rock properties in elastic and viscoelastic rheologies. Crustal heterogeneity is constrained by seismic velocity data that indicate the presence of a large low‐velocity zone, the Altiplano‐Puna magma body, at depths of ~17 km below the surface. A viscoelastic rheology is employed to account for time‐dependent deformation and an inelastic crust. Comparing homogeneous and heterogeneous models demonstrates the significant impact of a mechanically weak, source‐depth layer, which alters surface displacement patterns by buffering subsurface deformation. Elastic model results guide the source parameters tested in the viscoelastic models and demonstrate a range of possible causative source geometries. Our preferred model suggests that pressurization of a magma source extending upward from the Altiplano‐Puna magma body is causing the observed surface uplift and alludes to a continued increase in this pressure to explain both the spatial and temporal patterns. We also demonstrate how a pressure‐time function plays a first‐order role in explaining the observed temporal deformation pattern.
High density of structurally controlled, shallow to deep water fluid seep indicators imaged offshore Costa Rica
Authors: Kluesner Jared W. , Silver Eli A. , Bangs Nathan L. , McIntosh Kirk D. , Gibson James , Orange Daniel , Ranero Cesar R. , von Huene Roland
Published: February 2013

We used high‐resolution mapping to document 161 sites of potential fluid seepage on the shelf and slope regions where no geophysical seep indicators had been reported. Identified potential seabed seepage sites show both high‐backscatter anomalies and bathymetric expressions, such as pockmarks, mounds, and ridges. Almost all identified seabed features are associated with bright spots and flat spots beneath, as mapped within the 3‐D seismic grid. We obtained EM122 multi‐beam data using closely spaced receiver beams and 4–5 times overlapping multi‐beam swaths, which greatly improved the sounding density and geologic resolvability of the data. At least one location shows an acoustic plume in the water column on a 3.5 kHz profile, and this plume is located along a fault trace and above surface and subsurface seepage indicators. Fluid indicators are largely associated with folds and faults within the sediment section, and many of the faults continue into and offset the reflective basement. A dense pattern of normal faults is seen on the outer shelf in the multi‐beam bathymetry, backscatter, and 3‐D seismic data, and the majority of fluid seepage indicators lie along mapped fault traces. Furthermore, linear mounds, ridges, and pockmark chains are found on the upper, middle, and lower slope regions. The arcuate shape of the shelf edge, projection of the Quepos Ridge, and high density of potential seep sites suggest that this area may be a zone of former seamount/ridge subduction. These results demonstrate a much greater potential seep density and distribution than previously reported across the Costa Rican margin.
Thellier GUI: An integrated tool for analyzing paleointensity data from Thellier‐type experiments
Authors: Shaar Ron , Tauxe Lisa
Published: February 2013

Thellier‐type experiments are a method used to estimate the intensity of the ancient geomagnetic field from samples carrying thermoremanent magnetization. The analysis of Thellier‐type experimental data is conventionally done by manually interpreting data from each specimen individually. The main limitations of this approach are: (1) manual interpretation is highly subjective and can be biased by misleading concepts, (2) the procedure is time consuming, and (3) unless the measurement data are published, the final results cannot be reproduced by readers. These issues compound when trying to combine together paleointensity data from a collection of studies. Here, we address these problems by introducing the Thellier GUI: a comprehensive tool for interpreting Thellier‐type experimental data. The tool presents a graphical user interface, which allows manual interpretation of the data, but also includes two new interpretation tools: (1) Thellier Auto Interpreter: an automatic interpretation procedure based on a given set of experimental requirements, and 2) Consistency Test: a self‐test for the consistency of the results assuming groups of samples that should have the same paleointensity values. We apply the new tools to data from two case studies. These demonstrate that interpretation of non‐ideal Arai plots is nonunique and different selection criteria can lead to significantly different conclusions. Hence, we recommend adopting the automatic interpretation approach, as it allows a more objective interpretation, which can be easily repeated or revised by others. When the analysis is combined with a Consistency Test, the credibility of the interpretations is enhanced. We also make the case that published paleointensity studies should include the measurement data (as supplementary files or as a contributions to the MagIC database) so that results based on a particular data set can be reproduced and assessed by others.
Olivine thermometry and source constraints for mantle fragments in the Navajo Volcanic Field, Colorado Plateau, southwest United States: Implications for the mantle wedge
Authors: Smith Douglas
Published: February 2013

The evolution of the mantle wedge below the Colorado Plateau during low‐angle subduction has been investigated by analysis of fragments from the Navajo Volcanic Field (NVF), most from serpentinized ultramafic microbreccia (SUM) diatremes. In most SUM‐hosted olivine, concentrations of Al and V are < 1 ppm, and Cr, Ca, and Na concentrations also are unusually low: most temperatures from three olivine thermometers (Al, Cr, and V‐based) are in the range 530°C to 650°C. The temperatures are consistent with the presence of chlorite in some inclusions, and they support the utility of olivine thermometry for diverse mineral assemblages in cool peridotite. Most pressures calculated for discrete diopside grains in SUM correspond to depths in the range 80 to 120 km. Diopside is relatively high in Li (~3.5 ppm), and two of five diopside grains have high Sr/Nd. SUM diatreme sources are inferred to be serpentine‐rich mélange tectonically eroded from the forearc, transported above the Farallon slab, and incorporated into the lithosphere of the Plateau. Garnet peridotite xenoliths from minettes of the NVF record deeper depths in the range 120 to 150 km. These garnet peridotites also may be from forearc mantle emplaced during Farallon subduction. Calculated temperatures preclude the possibility that asthenosphere was in contact with that lithosphere at or near 150 km depth for tens of m.y. before NVF formation. Structures observed in seismic images of mantle to depths of 150 km below the central Colorado Plateau may be related to Farallon subduction, not inherited from Proterozoic lithosphere.
Phase transitions of harzburgite and buckled slab under eastern China
Authors: Zhang Yanfei , Wang Yanbin , Wu Yao , Bina Craig R. , Jin Zhenmin , Dong Shuwen
Published: February 2013

Phase relations in harzburgite have been determined between 14 and 24 GPa and 1473 and 1673 K. At 1673 K, harzburgite transformed to wadsleyite + garnet + clinopyroxene below 19 GPa and decomposed into an assemblage of ringwoodite + garnet + stishovite above 20 GPa. Certain amounts of akimotoite were produced at still higher pressures (22–23 GPa). Finally, perovskite and magnesiowüstite were found to coexist with garnet at 24.2 GPa. Compositions of all the phases were analyzed and elemental partitioning coefficients were determined among coexisting phases. Combining our experimental data with available thermoelastic properties of major minerals in the earth's mantle, we modeled the velocity and density signatures of the stagnated oceanic slab in the mantle transition zone (MTZ) under eastern China, based on kinematic slab thermal structure analysis. We examined two end‐member slab models: a conventional straight slab with deformation thickening and an undulate slab with an oscillating wavelength of 200 km. We found that an undulated (buckled) slab model yields velocity anomalies (about 1–2% for Vp) that are consistent with seismic tomography models, taking into account low‐pass filtering effects in seismic tomography studies. On the other hand, straight slab models yield velocity anomalies that are too high compared with seismic tomography models. Our models provide important constraints on the thermal structure, mineralogy, composition, density, and velocities of slab materials in the MTZ.
Bunched black (and grouped grey) swans: Dissipative and non‐dissipative models of correlated extreme fluctuations in complex geosystems
Authors: Watkins N. W.
Published: February 2013

I review the hierarchy of approaches to complex systems, focusing particularly on stochastic equations. I discuss how the main models advocated by the late Benoit Mandelbrot fit into this classification, and how they continue to contribute to cross‐disciplinary approaches to the increasingly important problems of correlated extreme events and unresolved scales. The ideas have broad importance, with applications ranging across science areas as diverse as the heavy tailed distributions of intense rainfall in hydrology, after which Mandelbrot named the “Noah effect”; the problem of correlated runs of dry summers in climate, after which the “Joseph effect” was named; and the intermittent, bursty, volatility seen in finance and fluid turbulence.
Decadal time evolution of oceanic uptake of anthropogenic carbon in the Okhotsk Sea
Authors: Watanabe Yutaka W. , Nishioka Jun , Nakatsuka Takeshi
Published: February 2013

Comparing the data sets of chemical transient tracers (trichlorofluoromethane (CFC‐11), dichlorodifluoromethane (CFC‐12), sulfur hexafluoride (SF6)) among three re‐observations from 1993 to 2006 in the Okhotsk Sea, we found the remarkable change in the efficiency of oceanic absorption of anthropogenic carbon (EF) based on the observed change of apparent tracer age. EF above 27.0 σθ increased by 16 % while EF below 27.0 σθ declined by 27 % during the period from 1993 to 2006. Consequently, EF in the entire water column decreased by 14 %. We concluded that the recent reinforcement of ocean stratification derived from the ocean warming caused the weakening of water ventilation in this region, indicating that the penetration of atmospheric anthropogenic carbon to the deep ocean interior is becoming difficult.
Eddy impacts on the Florida Current
Authors: Frajka‐Williams E. , Johns W. E. , Meinen C. S. , Beal L. M. , Cunningham S. A.
Published: February 2013

The Gulf Stream in the Atlantic carries warm water northwards and forms both the return closure of the subtropical gyre as well as the upper limb of the meridional overturning circulation. Recent time series recorded east of the Bahamas at 26°N indicate that from May 2009 to April 2011, in contrast with past observations, the northward flowing Antilles Current covaried with the Gulf Stream in the Florida Straits—the Florida Current—even though the Florida and Antilles Currents are separated by banks and islands spanning 150 km. The peak‐to‐trough amplitude of transport variations during this period was 15 × 106 m3 s−1 for the Florida Current and 12 × 106 m3 s−1 for the Antilles Current, at time scales of 50 days to a year. From satellite observations, we show that the fluctuations in both the Florida and Antilles Currents between May 2009 and April 2011 are driven by eddy activity east of the Bahamas. Since the Florida Current time series is a critical time series for the state of the oceans, and often compared to climate models, this newly identified source of variability needs careful consideration when attributing the variability of the Florida Current to changes in the larger‐scale circulations (e.g., gyre and overturning) or wind forcing.
Aircraft measurements of very short‐lived halocarbons over the tropical Atlantic Ocean
Authors: Andrews S. J. , Jones C. E. , Carpenter L. J.
Published: February 2013

Atmospheric mixing ratios of C2H5I, CH2ClI, CH2Br2, and CHBr3 were quantified from whole air samples collected aboard the FAAM BAe 146‐301 atmospheric research aircraft during flights over the tropical Atlantic Ocean (30°N to 10°S) as part of the Trade Wind Ozone Photochemistry Experiment (TROMPEX) in September 2009. Mixing ratios of C2H5I and CH2ClI increased with decreasing latitude, and concentrations of all measured halocarbons were elevated with increasing proximity to the oceanic upwelling along the coast of Mauritania. Vertical profiles highlighted the rapid photolytic degradation of these compounds within the tropical troposphere, with CH2ClI concentrations reduced by 50% at the top of the boundary layer. The spatial distributions of CH2ClI indicated an open ocean source.
On the seeding of equatorial spread F by gravity waves
Authors: Krall J. , Huba J. D. , Fritts D. C.
Published: February 2013

The Naval Research Laboratory three‐dimensional simulation code SAMI3/ESF is used to study the response of the postsunset ionosphere to plane gravity waves. The effect of the vertical wind component of the wave is included as well as the effect of the background vertical wind, which can suppress equatorial spread F (ESF). It is shown that the strength of the coupling of the gravity wave to ESF increases with the vertical wavelength of the gravity wave. Long vertical wavelength modes (λ > 100 km) are more effective for seeding ESF.
High emission of carbon dioxide and methane during ice thaw in high latitude lakes
Authors: Karlsson Jan , Giesler Reiner , Persson Jenny , Lundin Erik
Published: February 2013

The winter period is seldom included in the estimates of aquatic‐atmospheric carbon exchange. In this study we quantified the flux of carbon dioxide (CO2) and methane (CH4) over 3 years from 12 small subarctic lakes. The lakes accumulated consistent and high amounts of CO2 and CH4 (56–97% as CO2) over the winter, resulting in a high flux during ice thaw. The CO2 flux during ice thaw increased with increasing mean depth of the lakes, while the CH4 flux was high in lakes surrounded by mires. The ice thaw period was quantitatively important to the annual gas balances of the lakes. For nine of the lakes, 11 to 55% of the annual flux occurred during thaw. For three of the lakes with an apparent net annual CO2 uptake, including the thaw period reversed the balance from sink to source. Our results suggest that the ice thaw period is critically important for the emissions of CO2 and CH4 in small lakes.
Buildup of aerosols over the Indian Region
Authors: Krishna Moorthy K. , Suresh Babu S. , Manoj M. R. , Satheesh S. K.
Published: February 2013

Climate change has great significance globally in general and South Asia in particular. Here we have used data from a network of 35 aerosol observatories over the Indian region to generate the first time regional synthesis using primary data and estimate the aerosol trends. On an average, aerosol optical depth (AOD) was found increasing at a rate of 2.3% (of its value in 1985) per year and more rapidly (~4%) during the last decade. If the trends continue so, AOD at several locations would nearly double and approach unity in the next few decades leading to an enhancement in aerosol‐induced lower atmospheric warming by a factor of two. However, a regionally averaged scenario can be ascertained only in the coming years, when longer and denser data would become available. The regional and global climate implications of such trends in the forcing elements need to be better assessed using GCMs.
Interdecadal variability in tropical cyclone frequency over the South China Sea and its association with the Indian Ocean sea surface temperature
Authors: Wang Lei , Huang Ronghui , Wu Renguang
Published: February 2013

During the period 1958–2001, the frequency of tropical cyclone (TC) genesis over the South China Sea (SCS) experienced an obvious interdecadal change around the mid‐1970s. Compared to the period from late 1950s to early 1970s, the number of TCs is significantly reduced during mid‐1970s through late 1990s. This interdecadal change in the TC frequency appears to relate to the increase in sea surface temperature (SST) of the tropical Indian Ocean. The difference of the circulation between the warm phase and the cold phase of the tropical Indian Ocean SST provides support for the influence of the tropical Indian Ocean warming on the variability of the TC frequency over the SCS. In the warm phase, lower‐level convergent and ascending flows over the tropical Indian Ocean are accompanied by upper‐level divergent flows, part of which go toward the SCS, leading to upper‐level convergence and descent there. Consequently, two lower‐level anticyclones develop and the TC genesis is suppressed over the SCS.
A new method for rainfall estimation through soil moisture observations
Authors: Brocca L. , Moramarco T. , Melone F. , Wagner W.
Published: February 2013

Rainfall and soil moisture, SM, are two important quantities for modeling the interaction between the land surface and the atmosphere. Usually, rainfall observations are used as input data for modeling the time evolution of SM within hydrological and land surface models. In this study, by inverting the soil‐water balance equation, a simple analytical relationship for estimating rainfall accumulations from the knowledge of SM time series is obtained. In situ and satellite SM observations from three different sites in Italy, Spain, and France are used to test the reliability of the proposed approach in contrasting climatic conditions. The results show that the model is able to satisfactorily reproduce daily rainfall data when in situ SM observations are employed (correlation coefficient, R, nearly equal to 0.9). Furthermore, also by using satellite data reasonable results are obtained in reproducing 4 day rainfall accumulations with R‐values close to 0.8. Based on these preliminary results, the proposed approach can be adopted conveniently to improve rainfall estimation at a catchment scale and as a supplementary source of data to estimate rainfall at a global scale.
A TEX86 lake record suggests simultaneous shifts in temperature in Central Europe and Greenland during the last deglaciation
Authors: Blaga Cornelia I. , Reichart Gert‐Jan , Lotter André F. , Anselmetti Flavio S. , Sinninghe Damsté Jaap S.
Published: February 2013

High‐resolution quantitative temperature records from continents covering glacial to interglacial transitions are scarce but important for understanding the climate system. We present the first decadal resolution record of continental temperatures in Central Europe during the last deglaciation (~14,600–10,600 cal. yr B.P.) based on the organic geochemical palaeothermometer TEX86. The TEX86‐inferred temperature record from Lake Lucerne (Vierwaldstättersee, Switzerland) reveals typical oscillations during the Late Glacial Interstadial, followed by an abrupt cooling of 2°C at the onset of Younger Dryas and a rapid warming of 4°C at the onset of the Holocene, within less than 350 years. The remarkable resemblance with the Greenland and regional stable oxygen isotope records suggests that temperature changes in continental Europe were dominated by large‐scale reorganizations in the northern hemispheric climate system.
North American monsoon precipitation reconstructed from tree‐ring latewood
Authors: Griffin Daniel , Woodhouse Connie A. , Meko David M. , Stahle David W. , Faulstich Holly L. , Carrillo Carlos , Touchan Ramzi , Castro Christopher L. , Leavitt Steven W.
Published: February 2013

The North American monsoon is a major focus of modern and paleoclimate research, but relatively little is known about interannual‐ to decadal‐scale monsoon moisture variability in the pre‐instrumental era. This study draws from a new network of subannual tree‐ring latewood width chronologies and presents a 470‐year reconstruction of monsoon (June–August) standardized precipitation for southwestern North America. Comparison with an independent reconstruction of cool‐season (October–April) standardized precipitation indicates that southwestern decadal droughts of the last five centuries were characterized not only by cool‐season precipitation deficits but also by concurrent failure of the summer monsoon. Monsoon drought events identified in the past were more severe and persistent than any of the instrumental era. The relationship between winter and summer precipitation is weak, at best, and not time stable. Years with opposing‐sign seasonal precipitation anomalies, as noted by other studies, were anomalously frequent during the mid to late 20th century.
Linkages between lake shrinkage/expansion and sublacustrine permafrost distribution determined from remote sensing of interior Alaska, USA
Authors: Jepsen S. M. , Voss C. I. , Walvoord M. A. , Minsley B. J. , Rover J.
Published: February 2013

Linkages between permafrost distribution and lake surface‐area changes in cold regions have not been previously examined over a large scale because of the paucity of subsurface permafrost information. Here, a first large‐scale examination of these linkages is made over a 5150 km2 area of Yukon Flats, Alaska, USA, by evaluating the relationship between lake surface‐area changes during 1979–2009, derived from Landsat satellite data, and sublacustrine groundwater flow‐path connectivity inferred from a pioneering, airborne geophysical survey of permafrost. The results suggest that the shallow (few tens of meters) thaw state of permafrost has more influence than deeper permafrost conditions on the evolving water budgets of lakes on a multidecadal time scale. In the region studied, these key shallow aquifers have high hydraulic conductivity and great spatial variability in thaw state, making groundwater flow and associated lake level evolution particularly sensitive to climate change owing to the close proximity of these aquifers to the atmosphere.
Mineral carbon sequestration and induced seismicity
Authors: Yarushina Viktoriya M. , Bercovici David
Published: February 2013

The seismic safety of current technologies for CO2 sequestration has been questioned in several recent publications and whitepapers. While there is a definite risk from unbalanced subsurface fluid injection because of hydraulic fracturing, we propose a simple model to demonstrate that mineral carbonation in mafic rocks can mitigate seismic risk. In particular, mineral precipitation will increase the solid grain‐grain contact area, which reduces the effective fluid pressure, distributes the deviatoric stress load, and increases frictional contact. Thus, mineral sequestration can potentially reduce seismic risk provided fluid pumping rates do not exceed a critical value.
Thermospheric damping response to sheath‐enhanced geospace storms
Authors: Knipp D. , Kilcommons L. , Hunt L. , Mlynczak M. , Pilipenko V. , Bowman B. , Deng Y. , Drake K.
Published: February 2013

We show evidence that solar wind density enhancements and pressure pulses can lead to intense low‐energy particle precipitation and an associated, but unexpected, damping of thermospheric density response. Ground‐based indices, used as proxies for thermospheric energy deposition, fail to capture these interactions in forecasting algorithms. Superposed epoch comparison of a group of poorly specified neutral density storms suggests an event‐chain of (1) multi‐hour, pre‐storm solar wind density enhancement, followed by solar wind dynamic pressure pulses that trigger excess low‐energy particle flux to the upper atmosphere; (2) enhanced production of thermospheric Nitric Oxide (NO) by precipitating particles and storm heating; (3) NO infrared cooling and damping of the thermosphere; and (4) mis‐forecast of neutral density. In the control storms, these features are absent or muted. We discuss the roles of solar wind pre‐conditioning and solar cycle dependency in the problem storms. These problem neutral‐density storms reveal an element of “geo‐effectiveness” that highlights competition between hydrodynamic aspects of the solar wind and other interplanetary drivers.
The agricultural history of human‐nitrogen interactions as recorded in ice core δ15N‐NO3−
Authors: Felix J. David , Elliott Emily M.
Published: February 2013

The advent and industrialization of the Haber Bosch process in the early twentieth century ushered in a new era of reactive nitrogen distributions on Earth. Since the appearance of the first commercial scale Haber Bosch fertilizer plants, fertilizer application rates have greatly increased in the U.S. While the contributions of fertilizer runoff to eutrophication and anoxic dead zones in coastal regions have been well‐documented, the potential influences of increased fertilizer applications on air quality and precipitation chemistry are poorly constrained. Here we combine a 255‐year record of precipitation nitrate isotopes preserved in a Greenland ice core, historical reconstructions of fertilizer application rates, and field characterization of the isotopic composition of nitrogen oxides produced biogenically in soils, to provide new constraints on the contributions of biogenic emissions to North American NOx inventories. Our results indicate that increases in twentieth century commercial fertilizer use led to large increases in soil NO, a byproduct released during nitrification and denitrification reactions. These large shifts in soil NO production are evidenced by sharp declines in ice core δ15N‐NO3− values. Further, these results suggest that biogenic NOx emissions are underestimated by two to four fold in the U.S. NOx emission inventories used to construct global reactive nitrogen budgets. These results demonstrate that nitrate isotopes in ice cores, coupled with newly constrained δ15N‐NOx values for NOx emission sources, provide a novel means for estimating contemporary and historic contributions from individual NOx emission sources to deposition.
Whose Rights Count? Negotiating Practice, Policy, and Legal Dilemmas Regarding Infant–Parent Contact When Infants are in Out‐of‐Home Care
Authors: Miron Devi , Bisaillon Claud , Jordan Brigid , Bryce Graham , Gauthier Yvon , St‐Andre Martin , Minnis Helen
Published: February 2013

This article takes a human rights perspective with a view to articulating the infant's perspective when the infant has been subjected to abuse, neglect, or both and is reliant on the state to ensure his or her health and well‐being. When a young child is removed from parental care, important and often difficult decisions have to be made about subsequent contact between child and parent. We consider a number of dilemmas which may arise for practitioners when they are assisting child welfare decision makers in relation to contact, and acknowledge the limited empirical follow‐up studies of the impact of child welfare practice and legal decisions on infant outcomes. We draw on the significant and substantive evidence base about infant emotional and cognitive development and infant–parent attachment relationships as well as infant mental health to illuminate the infant's subjective experience in these practice dilemmas. We describe innovations in practice from various countries, which seek to shed light on the challenges often associated with contact.
IDIOSYNCRATIC VARIABLES THAT AFFECT FUNCTIONAL ANALYSIS OUTCOMES: A REVIEW (2001–2010)
Authors: Schlichenmeyer Kevin J. , Roscoe Eileen M. , Rooker Griffin W. , Wheeler Emily E. , Dube William V.
Published: February 2013

Although typical functional analyses often produce clear outcomes, some studies have reported ambiguous results that cannot be interpreted. Such undifferentiated outcomes may occur if test conditions do not include relevant antecedent or consequent events. Clinicians then may try to modify the functional analysis conditions to include those events. Hanley, Iwata, and McCord (2003) reviewed the functional analysis literature through 2000 and described idiosyncratic variables included in modified functional analyses. The objective of the present review was to present a quantitative analysis of idiosyncratic antecedents and consequences in modified functional analyses during the past decade (2001 to 2010). We discuss the range of stimulus parameters tested and the assessment strategies used for informing the modified analysis conditions.
DOES SUPPLEMENTARY REINFORCEMENT OF STEREOTYPY FACILITATE EXTINCTION?
Authors: Dozier Claudia L. , Iwata Brian A. , Wilson David M. , Thomason‐Sassi Jessica L. , Roscoe Eileen M.
Published: February 2013

Results of several studies suggest that delivery of supplemental (social) reinforcement for stereotypy might facilitate its subsequent extinction. We examined this possibility with 9 subjects who engaged in stereotypy by including methodological refinements to ensure that (a) subjects' stereotypy was maintained in the absence of social consequences, (b) supplementary reinforcers were highly preferred and were shown to be reinforcers for some behavior, and (c) subjects were exposed to lengthy reinforcement and extinction conditions. In spite of these modifications, only 4 subjects' stereotypy increased when supplementary reinforcement was delivered contingent on stereotypy, and no subject's stereotypy decreased below initial baseline levels when social reinforcement was subsequently withheld. Decreases in stereotypy occurred with the implementation of noncontingent reinforcement. Thus, delivery of supplementary reinforcers either did not increase stereotypy or did not facilitate extinction of stereotypy maintained by automatic reinforcement. We discuss the practical and conceptual bases of these results with respect to our current understanding of function‐based interventions.
AN INDIVIDUALIZED AND COMPREHENSIVE APPROACH TO TREATING SLEEP PROBLEMS IN YOUNG CHILDREN
Authors: Jin C. Sandy , Hanley Gregory P. , Beaulieu Lauren
Published: February 2013

We evaluated the effects of assessment‐based interventions on the treatment of sleep problems in 3 young children, 2 of whom had been diagnosed with autism. We used sleep diaries and infrared nighttime video in the child's bedroom to obtain measures of sleep onset, sleep‐interfering behaviors, night waking, total sleep, parental presence, and medication administration each night. We then identified environmental factors that contributed to sleep problems using an open‐ended interview called the Sleep Assessment and Treatment Tool. Individualized treatment packages were designed with the children's parents based on the idiosyncratic results of the assessment. Treatment packages included adjustment of the sleep schedule based on developmental norms and current sleep phases, design of a sleep‐conducive environment, elimination of inappropriate sleep dependencies, and function‐based interventions to decrease sleep‐interfering behaviors by disrupting the contingency between the interfering behavior and its likely reinforcement. A nonconcurrent multiple baseline design across subjects revealed that treatment was effective for all 3 children. In addition, social acceptability measures showed that the parents were satisfied with the assessment process, the treatment, and the amount of behavior change.
TRAINING RESIDENTIAL STAFF TO CONDUCT TRIAL‐BASED FUNCTIONAL ANALYSES
Authors: Lambert Joseph M. , Bloom Sarah E. , Kunnavatana S. Shanun , Collins Shawnee D. , Clay Casey J.
Published: February 2013

We taught 6 supervisors of a residential service provider for adults with developmental disabilities to train 9 house managers to conduct trial‐based functional analyses. Effects of the training were evaluated with a nonconcurrent multiple baseline. Results suggest that house managers can be trained to conduct trial‐based functional analyses with a high degree of procedural fidelity.
EVALUATION OF THE DIVIDED ATTENTION CONDITION DURING FUNCTIONAL ANALYSES
Authors: Fahmie Tara A. , Iwata Brian A. , Harper Jill M. , Querim Angie C.
Published: February 2013

A common condition included in most functional analyses (FAs) is the attention condition, in which the therapist ignores the client by engaging in a solitary activity (antecedent event) but delivers attention to the client contingent on problem behavior (consequent event). The divided attention condition is similar, except that the antecedent event consists of the therapist conversing with an adult confederate. We compared the typical and divided attention conditions to determine whether behavior in general (Study 1) and problem behavior in particular (Study 2) were more sensitive to one of the test conditions. Results showed that the divided attention condition resulted in faster acquisition or more efficient FA results for 2 of 9 subjects, suggesting that the divided attention condition could be considered a preferred condition when resources are available.
A simplified PDF parameterization of subgrid‐scale clouds and turbulence for cloud‐resolving models
Authors: Bogenschutz Peter A. , Krueger Steven K.
Published: February 2013

Over the past decade a new type of global climate model (GCM) has emerged, which is known as a multiscale modeling framework (MMF). Colorado State University's MMF represents a coupling between the Community Atmosphere Model and the System for Atmospheric Modeling (SAM) to serve as the cloud‐resolving model (CRM) that replaces traditionally parameterized convection in GCMs. However, due to the high computational expense of the MMF, the grid size of the embedded CRM is typically limited to 4 km for long‐term climate simulations. With grid sizes this coarse, shallow convective processes and turbulence cannot be resolved and must still be parameterized within the context of the embedded CRM. This paper describes a computationally efficient closure that aims to better represent turbulence and shallow convective processes in coarse‐grid CRMs. The closure is based on the assumed probability density function (PDF) technique to serve as the subgrid‐scale (SGS) condensation scheme and turbulence closure that employs a diagnostic method to determine the needed input moments. This paper describes the scheme, as well as the formulation of the eddy length which is empirically determined from large eddy simulation (LES) data. CRM tests utilizing the closure yields good results when compared to LESs for two trade‐wind cumulus cases, a transition from stratocumulus to cumulus, and continental cumulus. This new closure improves the representation of clouds through the use of SGS condensation scheme and turbulence due to better representation of the buoyancy flux and dissipation rates. In addition, the scheme reduces the sensitivity of CRM simulations to horizontal grid spacing. The improvement when compared to the standard low‐order closure configuration of the SAM is especially striking.
Hurricanes in an aquaplanet world: Implications of the impacts of external forcing and model horizontal resolution
Authors: Li Fuyu , Collins William D. , Wehner Michael F. , Leung L. Ruby
Published: February 2013

High‐resolution climate models have been shown to improve the statistics of tropical storms (TCs) and hurricanes compared to low‐resolution models. The impact of increasing horizontal resolution in the TC simulation is investigated exclusively using a series of Atmospheric Global Climate Model (AGCM) runs with idealized aquaplanet steady‐state boundary conditions and a fixed operational storm‐tracking algorithm. The results show that increasing horizontal resolution helps to detect more hurricanes, simulate stronger extreme rainfall, and emulate better storm structures in the models. However, increasing model resolution does not necessarily produce stronger hurricanes in terms of maximum wind speed, minimum sea‐level pressure, and mean precipitation, as the increased number of storms simulated by high‐resolution models is mainly associated with weaker storms. The spatial scale at which the analyses are conducted appears to have more important control on these meteorological statistics compared to horizontal resolution of the model grid. When the simulations are analyzed on common low‐resolution grids, the statistics of the hurricanes, particularly the hurricane counts, show reduced sensitivity to the horizontal grid resolution and signs of scale invariance.
Trends in hip fracture rates in Canada: An age-period-cohort analysis
Authors: Jean Sonia , O'Donnell Siobhan , Lagacé Claudia , Walsh Peter , Bancej Christina , Brown Jacques P , Morin Suzanne , Papaioannou Alexandra , Jaglal Susan B , Leslie William D ,   for the Osteoporosis Surveillance Expert Working Group
Published: February 2013

Age-standardized rates of hip fracture in Canada declined during the period 1985 to 2005. We investigated whether this incidence pattern is explained by period effects, cohort effects, or both. All hospitalizations during the study period with primary diagnosis of hip fracture were identified. Age- and sex-specific hip fracture rates were calculated for nineteen 5-year age groups and four 5-year calendar periods, resulting in 20 birth cohorts. The effect of age, calendar period, and birth cohort on hip fracture rates was assessed using age-period-cohort models as proposed by Clayton and Schiffers. From 1985 to 2005, a total of 570,872 hospitalizations for hip fracture were identified. Age-standardized rates for hip fracture have progressively declined for females and males. The annual linear decrease in rates per 5-year period were 12% for females and 7% for males (both p < 0.0001). Significant birth cohort effects were also observed for both sexes (p < 0.0001). Cohorts born before 1950 had a higher risk of hip fracture, whereas those born after 1954 had a lower risk. After adjusting for age and constant annual linear change (drift term common to both period and cohort effects), we observed a significant nonlinear birth cohort effect for males (p = 0.0126) but not for females (p = 0.9960). In contrast, the nonlinear period effect, after adjustment for age and drift term, was significant for females (p = 0.0373) but not for males (p = 0.2515). For males, we observed no additional nonlinear period effect after adjusting for age and birth cohort, whereas for females, we observed no additional nonlinear birth cohort effect after adjusting for age and period. Although hip fracture rates decreased in both sexes, different factors may explain these changes. In addition to the constant annual linear decrease, nonlinear birth cohort effects were identified for males, and calendar period effects were identified for females as possible explanations.
Periapical Disease and Bisphosphonates Induce Osteonecrosis of the Jaws in Mice
Authors: Kang Ben , Cheong Simon , Chaichanasakul Thawinee , Bezouglaia Olga , Atti Elisa , Dry Sarah M , Pirih Flavia Q , Aghaloo Tara L , Tetradis Sotirios
Published: February 2013

Osteonecrosis of the jaw (ONJ) is a well-recognized complication of antiresorptive medications, such as bisphosphonates (BPs). Although ONJ is most common after tooth extractions in patients receiving high-dose BPs, many patients do not experience oral trauma. Animal models using tooth extractions and high BP doses recapitulate several clinical, radiographic, and histologic findings of ONJ. We and others have reported on rat models of ONJ using experimental dental disease in the absence of tooth extraction. These models emphasize the importance of dental infection/inflammation for ONJ development. Here, we extend our original report in the rat, and present a mouse model of ONJ in the presence of dental disease. Mice were injected with high dose zoledronic acid and pulpal exposure of mandibular molars was performed to induce periapical disease. After 8 weeks, quantitative and qualitative radiographic and histologic analyses of mouse mandibles were done. Periapical lesions were larger in vehicle-treated versus BP-treated mice. Importantly, radiographic features resembling clinical ONJ, including thickening of the lamina dura, periosteal bone deposition, and increased trabecular density, were seen in the drilled site of BP-treated animals. Histologically, osteonecrosis, periosteal thickening, periosteal bone apposition, epithelial migration, and bone exposure were present in the BP-treated animals in the presence of periapical disease. No difference in tartrate-resistant acid phosphatase (TRAP)+ cell numbers was observed, but round, detached, and removed from the bone surface cells were present in BP-treated animals. Although 88% of the BP-treated animals showed areas of osteonecrosis in the dental disease site, only 33% developed bone exposure, suggesting that osteonecrosis precedes bone exposure. Our data further emphasize the importance of dental disease in ONJ development, provide qualitative and quantitative measures of ONJ, and present a novel mouse ONJ model in the absence of tooth extraction that should be useful in further exploring ONJ pathophysiological mechanisms.