bluuebunny/crossref_metadata_2025 huggingface dataset:
Quality of Life following Total Laryngectomy: Assessment Using the UW-QOL Scale
Authors: Kazi R. , De Cordova J. , Kanagalingam J. , Venkitaraman R. , Nutting C.M. , Clarke P. , Rhys-Evans P. , Harrington K.J.
Published: December 2006

Objectives: To determine the quality of life (QOL) in patients using valved speech following total laryngectomy with a validated patient self-report scale. Study Design: Cross-sectional cohort study. Patients: 63 patients following total laryngectomy using valved speech. Intervention: University of Washington Quality of Life (UW-QOL) questionnaire. Main Outcome Measures: Patient perception of the QOL over the last 7 days following total laryngectomy in response to specific questions and correlated with sociodemographic and treatment factors. Results: Responses were received from 44 males and 11 females (response rate: 87.3%) with a median age of 66 years (range: 40–84). The mean (SD) composite score of the QOL in our series of patients with total laryngectomy was 81.3 (10.9). As regards the overall QOL, 80% of our patients cited it as very good (45.5%) to good (34.5%). Patients identified speech, appearance, and activity as the most important issues following total laryngectomy. Only age and pharyngo-oesophageal segment closure were significant predictors of QOL scores (Student t test, p < 0.05) and not other demographic and treatment variables. Conclusions: The composite score and overall QOL were high in our series of total laryngectomy patients and this possibly reflects adequate multidisciplinary management. We strongly urge the use of prospective longitudinal studies that will adequately identify any QOL changes over time. Although the UW-QOL questionnaire is a simple and brief scale, it has limitations that can curtail its effective use in laryngectomy patients and we advise supplementing it with the use of domain-specific questionnaires.
The Effect of Potential Future Climate Change on the Marine Methane Hydrate Stability Zone
Authors: Fyke Jeremy G. , Weaver Andrew J.
Published: December 2006

The marine gas hydrate stability zone (GHSZ) is sensitive to temperature changes at the seafloor, which likely affected the GHSZ in the past and may do so in the future in response to anthropogenic greenhouse gas emissions. A series of climate sensitivity and potential future climate change experiments are undertaken using the University of Victoria Earth System Climate Model (UVic ESCM) with resulting seafloor temperature changes applied to a simple time-dependent methane hydrate stability model. The global GHSZ responds significantly to elevated atmospheric CO2 over time scales of 103 yr with initial decreases of the GHSZ occurring after 200 yr in shallow high-latitude seafloor areas that underlie regions of sea ice loss. The magnitude and rate of GHSZ change is dependent primarily upon the thermal diffusivity of the seafloor and the magnitude and duration of the seafloor temperature increase. Using a simple approximation of the amount of carbon stored as hydrate in the GHSZ, estimates of carbon mobilized due to hydrate dissociation are made for several potential climate change scenarios.
Some Overlooked Features of Tropical Atlantic Climate Leading to a New Niño-Like Phenomenon*
Authors: Okumura Yuko , Xie Shang-Ping
Published: December 2006

The Atlantic Niño, an equatorial zonal mode akin to the Pacific El Niño–Southern Oscillation (ENSO), is phase-locked to boreal summer when the equatorial easterly winds intensify and the thermocline shoals in the Gulf of Guinea. A suite of satellite and in situ observations reveals a new mode of tropical Atlantic variability that displays many characteristics of the zonal mode but instead peaks in November–December (ND). This new mode is found to be statistically independent from both the Atlantic Niño in the preceding summer and the Pacific ENSO. The origin of this ND zonal mode lies in an overlooked aspect of the seasonal cycle in the equatorial Atlantic.

In November the equatorial easterly winds intensify for the second time, increasing upwelling and lifting the thermocline in the Gulf of Guinea. An analysis of high-resolution climatological data shows that these dynamical changes induce a noticeable SST cooling in the central equatorial Atlantic. The shoaling thermocline and increased upwelling enhance the SST sensitivity to surface wind changes, reinvigorating equatorial ocean–atmosphere interaction. The resultant ocean–atmospheric anomalies are organized into patterns that give rise to positive mutual feedback as Bjerknes envisioned for the Pacific ENSO. This ND zonal mode significantly affects interannual rainfall variability in coastal Congo–Angola during its early rainy season. It tends to further evolve into a meridional mode in the following March–April, affecting precipitation in northeast Brazil. Thus it offers potential predictability for climate over the Atlantic sector in early boreal winter, a season for which local ocean–atmosphere variability was otherwise poorly understood.
A Climatology of Tropospheric Zonal-Mean Water Vapor Fields and Fluxes in Isentropic Coordinates
Authors: Schneider Tapio , Smith Karen L. , O’Gorman Paul A. , Walker Christopher C.
Published: December 2006

Based on reanalysis data for the years 1980–2001 from the European Centre for Medium-Range Weather Forecasts (ERA-40 data), a climatology of tropospheric zonal-mean water vapor fields and fluxes in isentropic coordinates is presented. In the extratropical free troposphere, eddy fluxes dominate the meridional flux of specific humidity along isentropes. At all levels, isentropic eddy fluxes transport water vapor from the deep Tropics through the subtropics into the extratropics. Isentropic eddy fluxes of specific humidity diverge near the surface and in the tropical and subtropical free troposphere; they converge in the extratropical free troposphere. Isentropic mean advective fluxes of specific humidity play a secondary role in the meridional water vapor transport in the free troposphere; however, they dominate the meridional flux of specific humidity near the surface, where they transport water vapor equatorward and, in the solstice seasons, across the equator. Cross-isentropic mean advective fluxes of specific humidity are especially important in the Hadley circulation, in whose ascending branches they moisten and in whose descending branches they dry the free troposphere.

Near the minima of zonal-mean relative humidity in the subtropical free troposphere, the divergence of the cross-isentropic mean advective flux of specific humidity in the descending branches of the Hadley circulation is the dominant divergence in the mean specific humidity balance; it is primarily balanced by convergence of cross-isentropic turbulent fluxes that transport water vapor from the surface upward. Although there are significant isentropic eddy fluxes of specific humidity through the region of the subtropical relative humidity minima, their divergence near the minima is generally small compared with the divergence of cross-isentropic mean advective fluxes, implying that moistening by eddy transport from the Tropics into the region of the minima approximately balances drying by eddy transport into the extratropics. That drying by cross-isentropic mean subsidence near the subtropical relative humidity minima is primarily balanced by moistening by upward turbulent fluxes of specific humidity, likely in convective clouds, suggests cloud dynamics may play a central role in controlling the relative humidity of the subtropical free troposphere.
Ancient Austrocedrus Tree-Ring Chronologies Used to Reconstruct Central Chile Precipitation Variability from a.d. 1200 to 2000
Authors: Le Quesne Carlos , Stahle David W. , Cleaveland Malcolm K. , Therrell Matthew D. , Aravena Juan Carlos , Barichivich Jonathan
Published: December 2006

An expanded network of moisture-sensitive tree-ring chronologies has been developed for central Chile from long-lived cypress trees in the Andean Cordillera. A regional ring width chronology of cypress sites has been used to develop well-calibrated and verified estimates of June–December precipitation totals for central Chile extending from a.d. 1200 to 2000. These reconstructions are confirmed in part by historical references to drought in the seventeenth and eighteenth centuries and by nineteenth-century observations on the position of the Río Cipreses glacier. Analyses of the return intervals between droughts in the instrumental and reconstructed precipitation series indicate that the probability of drought has increased dramatically during the late nineteenth and twentieth centuries, consistent with selected long instrumental precipitation records and with the general recession of glaciers in the Andean Cordillera. This increased drought risk has occurred along with the growing demand on surface water resources and may heighten socioeconomic sensitivity to climate variability in central Chile.
A New Globally Complete Monthly Historical Gridded Mean Sea Level Pressure Dataset (HadSLP2): 1850–2004
Authors: Allan Rob , Ansell Tara
Published: December 2006

An upgraded version of the Hadley Centre’s monthly historical mean sea level pressure (MSLP) dataset (HadSLP2) is presented. HadSLP2 covers the period from 1850 to date, and is based on numerous terrestrial and marine data compilations. Each terrestrial pressure series used in HadSLP2 underwent a series of quality control tests, and erroneous or suspect values were either corrected, where possible, or removed. Marine observations from the International Comprehensive Ocean Atmosphere Data Set were quality controlled (assessed against climatology and near neighbors) and then gridded. The final gridded form of HadSLP2 was created by blending together the processed terrestrial and gridded marine MSLP data. MSLP fields were made spatially complete using reduced-space optimal interpolation. Gridpoint error estimates were also produced.

HadSLP2 was found to have generally stronger subtropical anticyclones and higher-latitude features across the Northern Hemisphere than an earlier product (HadSLP1). During the austral winter, however, it appears that the pressures in the southern Atlantic and Indian Ocean midlatitude regions are too high; this is seen in comparisons with both HadSLP1 and the 40-yr ECMWF Re-Analysis (ERA-40). Over regions of high altitude, HadSLP2 and ERA-40 showed consistent differences suggestive of potential biases in the reanalysis model, though the region over the Himalayas in HadSLP2 is biased compared with HadSLP1 and improvements are required in this region. Consistent differences were also observed in regions of sparse data, particularly over the higher latitudes of the Southern Ocean and in the southeastern Pacific. Unlike the earlier HadSLP1 product, error estimates are available with HadSLP2 to guide the user in these regions of low confidence.

An evaluation of major phenomena in the climate system using HadSLP2 provided further validation of the dataset. Important climatic features/indices such as the North Atlantic Oscillation, Arctic Oscillation, North Pacific index, Southern Oscillation index, Trans-Polar index, Antarctic Oscillation, Antarctic Circumpolar Wave, East Asian Summer Monsoon index, and the Siberian High index have all been resolved in HadSLP2, with extensions back to the mid-nineteenth century.
The Impact of Satellite Winds and Latent Heat Fluxes in a Numerical Simulation of the Tropical Pacific Ocean
Authors: Ayina Ludos-Herve , Bentamy Abderrahim , Mestas-Nuñez Alberto M. , Madec Gurvan
Published: December 2006

Several oceanic operational programs use remotely sensed fluxes to complement atmospheric operational analyses from major national weather prediction centers. The main goal of this study is to evaluate the ability of the ocean model (ORCA) to correctly simulate the dynamic of the tropical Pacific Ocean in 1996–98 when forced by the satellite turbulent fluxes (wind stress and latent heat fluxes). The results are compared with the oceanic response resulting from forcing the model with the European Centre for Medium-Range Weather Forecasts (ECMWF) operational analysis. Three sensitivity simulations forced with satellite and atmospheric analysis fields are performed. The control experiment is forced with the ECMWF fluxes. The solutions of these simulations are compared with data from the Tropical Atmosphere–Ocean (TAO) buoys and from sea surface temperatures analysis by Reynolds and Smith in the equatorial Pacific Ocean. The analysis results indicate that the model reproduces well the major spatial and temporal oceanic structures including the main characteristics of the 1997–98 El Niño. More specifically, the comparisons with buoys indicate that the experiment forced by the winds and the satellite latent heat fluxes is closer to the observations. They provide weak rms difference and strong correlations along the whole 500-m depth column. Furthermore, the correlations with the SST analysis vary between 75% and 95% compared to 65% and 77% for the experiment forced by ECMWF fluxes. The currents in the first 350 m also show a strong sensitivity to satellite turbulent fluxes.
The Effect of Environmental Conditions on Tropical Deep Convective Systems Observed from the TRMM Satellite
Authors: Lin Bing , Wielicki Bruce A. , Minnis Patrick , Chambers Lin , Xu Kuan-Man , Hu Yongxiang , Fan Alice
Published: December 2006

This study uses measurements of radiation and cloud properties taken between January and August 1998 by three Tropical Rainfall Measuring Mission (TRMM) instruments, the Clouds and the Earth’s Radiant Energy System (CERES) scanner, the TRMM Microwave Imager (TMI), and the Visible and Infrared Scanner (VIRS), to evaluate the variations of tropical deep convective systems (DCSs) with sea surface temperature and precipitation. The authors find that DCS precipitation efficiency increases with SST at a rate of ∼2% K−1. Despite increasing rainfall efficiency, the cloud areal coverage rises with SST at a rate of about 7% K−1 in the warm tropical seas. There, the boundary layer moisture supply for deep convection and the moisture transported to the upper troposphere for cirrus anvil cloud formation increase by ∼6.3% and ∼4.0% K−1, respectively. The changes in cloud formation efficiency, along with the increased transport of moisture available for cloud formation, likely contribute to the large rate of increasing DCS areal coverage. Although no direct observations are available, the increase of cloud formation efficiency with rising SST is deduced indirectly from measurements of changes in the ratio of DCS ice water path and boundary layer water vapor amount with SST. Besides the cloud areal coverage, DCS cluster effective sizes also increase with precipitation. Furthermore, other cloud properties, such as cloud total water and ice water paths, increase with SST. These changes in DCS properties will produce a negative radiative feedback for the earth’s climate system due to strong reflection of shortwave radiation by the DCS. These results significantly differ from some previously hypothesized dehydration scenarios for warmer climates, partially support the thermostat hypothesis but indicate a smaller magnitude of the negative feedback, and have great potential in testing current cloud-system-resolving models and convective parameterizations of general circulation models.
Winter North Atlantic Oscillation Hindcast Skill: 1900–2001
Authors: Fletcher Christopher G. , Saunders Mark A.
Published: December 2006

Recent proposed seasonal hindcast skill estimates for the winter North Atlantic Oscillation (NAO) are derived from different lagged predictors, NAO indices, skill assessment periods, and skill validation methodologies. This creates confusion concerning what is the best-lagged predictor of the winter NAO. To rectify this situation, a standardized comparison of NAO cross-validated hindcast skill is performed against three NAO indices over three extended periods (1900–2001, 1950–2001, and 1972–2001). The lagged predictors comprise four previously published predictors involving anomalies in North Atlantic sea surface temperature (SST), Northern Hemisphere (NH) snow cover, and an additional predictor, an index of NH subpolar summer air temperature (TSP). Significant (p < 0.05) NAO hindcast skill is found with May SST 1900–2001, summer/autumn SST 1950–2001, and warm season snow cover 1972–2001. However, the highest and most significant hindcast skill for all periods and all NAO indices is achieved with TSP. Hindcast skill is nonstationary using all predictors and is highest during 1972–2001 with a TSP correlation skill of 0.59 and a mean-squared skill score of 35%. Observational evidence is presented to support a dynamical link between summer TSP and the winter NAO. Summer TSP is associated with a contemporaneous midlatitude zonal wind anomaly. This leads a pattern of North Atlantic SST that persists through autumn. Autumn SSTs may force a direct thermal NAO response or initiate a response via a third variable. These findings suggest that the NH subpolar regions may provide additional winter NAO lagged predictability alongside the midlatitudes and the Tropics.
Bifurcation Structure of Thermohaline Millennial Oscillations
Authors: Colin de Verdière A. , Ben Jelloul M. , Sévellec F.
Published: December 2006

The question of the generation of millennial oscillations by internal ocean dynamics is studied through deliberate use of the simplest geometry and surface forcing, namely a hemispheric ocean with time-independent mixed boundary conditions (autonomous system). The lowest-order model that supports free oscillations has three horizontal and two vertical boxes. The essential ingredients permitting the existence of the oscillations are turbulent mixing and freshwater forcing. The finite amplitude oscillations share the advective–convective–diffusive characteristics of neighboring stable thermal and haline steady states. There are limits to the quantity of precipitation in polar regions for the existence of oscillatory states. When the freshwater forcing amplitude is increased, the system evolves from a stable thermal state through a global bifurcation to a finite amplitude limit cycle. The period of the limit cycle remains constant when freshwater is increased until at a second global bifurcation it becomes infinite with a logarithmic behavior characteristic of a homoclinic bifurcation. For still higher values of freshwater, the system locks into the stable haline steady state. These results are confirmed through the use of a two-dimensional latitude–depth model. A sensitivity study carried out with the latter shows that the period (away from the logarithmic singularity) varies as (vertical mixing)−1/3. The implications of these results for the Dansgaard–Oeschger oscillations of the last glacial period are threefold: First, internal ocean dynamics in a salt-conserving ocean basin and with time-independent boundary conditions are sufficient to allow free transitions between a strong thermal and a weak haline circulation regime provided that the precipitation in polar oceans does not exceed a certain threshold. It is noteworthy that the snow accumulation rates of the last glacial period were about a fourth of Holocene values. Second, the period of the oscillatory state is determined internally, a possible alternative to studies that require external periodic forcing. The range of the periods when estimated with present determinations of oceanic mixing easily accommodates the observations. Third, if the abrupt warming that signals the beginning of a Dansgaard–Oeschger event is interpreted through the present modeling results, its cause is linked to the efficiency of mixing to accumulate heat for a considerable amount of time in the deep ocean when the thermohaline circulation is weak.
Twentieth-Century Surface Air Temperature over China and the Globe Simulated by Coupled Climate Models
Authors: Zhou Tianjun , Yu Rucong
Published: December 2006

This paper examines variations of the surface air temperature (SAT) over China and the globe in the twentieth century simulated by 19 coupled climate models driven by historical natural and anthropogenic forcings. Most models perform well in simulating both the global and the Northern Hemispheric mean SAT evolutions of the twentieth century. The inclusion of natural forcings improves the simulation, in particular for the first half of the century. The reproducibility of the SAT averaged over China is lower than that of the global and hemispheric averages, but it is still acceptable. The contribution of natural forcings to the SAT over China in the first half of the century is not as robust as that to the global and hemispheric averages. No model could successfully produce the reconstructed warming over China in the 1920s. The prescribed natural and anthropogenic forcings in the coupled climate models mainly produce the warming trends and the decadal- to interdecadal-scale SAT variations with poor performances at shorter time scales. The prominent warming trend in the last half of the century over China and its acceleration in recent decades are weakly simulated. There are discrepancies between the simulated and observed regional features of the SAT trend over China. Few models could produce the summertime cooling over the middle part of eastern China (27°–36°N), while two models acceptably produce the meridional gradients of the wintertime warming trends, with north China experiencing larger warming. Limitations of the current state-of-the-art coupled climate models in simulating spatial patterns of the twentieth-century SAT over China cast a shadow upon their capability toward projecting credible geographical distributions of future climate change through Intergovernmental Panel on Climate Change (IPCC) scenario simulations.
Atmospheric Modes of Variability in a Changing Climate
Authors: Brandefelt Jenny
Published: December 2006

The response of the atmospheric circulation to an enhanced radiative greenhouse gas forcing in a transient integration with a coupled global climate model is investigated. The spatial patterns of the leading modes of Northern Hemisphere atmospheric variability are shown to change in response to the enhanced forcing. An earlier study showed that the spatial patterns of the leading modes in the Southern Hemisphere changed in response to the enhanced forcing. These changes were associated with changes in the propagation conditions for barotropic Rossby waves. This is, however, not the case for the Northern Hemisphere, where the propagation conditions are unchanged. Other possible mechanisms for the changes in the spatial patterns of the leading modes are discussed.
Blocking of the Kuroshio Large Meander by Baroclinic Interaction with the Izu Ridge
Authors: Mitsudera Humio , Taguchi Bunmei , Waseda Takuji , Yoshikawa Yasushi
Published: December 2006

This paper discusses the role of the Izu Ridge in blocking the Kuroshio large meander from propagating eastward across the ridge. It is shown that a combination of the sloping bottom with baroclinicity in the Kuroshio flow is important for blocking of the large meander. It produces a cyclonic torque over the western slope of the ridge when the large meander impinges upon it. That is, the cyclonic torque is formed ahead of the large meander, which results in blocking and amplification of the meander upstream of the Izu Ridge. The baroclinicity of the Kuroshio over the ridge is caused by baroclinic topographic Rossby waves generated when the large meander encounters the ridge.
Eulerian versus Lagrangian Approaches to the Wave-Induced Transport in the Upper Ocean
Authors: Weber Jan Erik H. , Broström Göran , Saetra Øyvind
Published: December 2006

It is demonstrated that the Eulerian and the Lagrangian descriptions of fluid motion yield the same form for the mean wave-induced volume fluxes in the surface layer of a viscous rotating ocean. In the Eulerian case, the volume fluxes are obtained in the familiar way by integrating the horizontal components of the Navier–Stokes equation in the vertical direction, as seen, for example, in the book by Phillips. In the direct Lagrangian approach, the perturbation equations for the second-order mean drift are integrated in the vertical direction. This yields the advantage that the form drag, which is a source term for the wave-induced transports, can be related to the virtual wave stress that acts to transfer dissipated mean wave momentum into mean currents. In particular, for waves that are periodic in space and time, comparisons between empirical and theoretical relations for the form drag yield an estimate for the wave-induced bulk turbulent eddy viscosity in the surface layer. A simplistic approach extends this analysis to account for wave breaking. By a generalization from a wave component to a wave spectrum, a set of equations for the wave-induced transport in the surface layer is derived for a fully developed sea. Solutions are discussed for an idealized spectral formulation. The problem is formulated such that a numerical wave prediction model can be used to generate the wave-forcing terms in a numerical barotropic ocean surge model. Results from the numerical simulations with a wave-influenced surge model are discussed and compared with similar results from forcing the surge model only by the traditional mean horizontal wind stress computed from the 10-m wind speed. For the simulations presented here, the wave-induced stress constitutes about 50% of the total atmospheric stress for moderate to strong winds.
Estimating the Sea Ice Compressive Strength from Satellite-Derived Sea Ice Drift and NCEP Reanalysis Data*
Authors: Tremblay L-B. , Hakakian M.
Published: December 2006

Satellite-derived sea ice drift maps and sea level pressure from reanalysis data are used to infer upper and lower bounds on the large-scale compressive strength of Arctic sea ice. To this end, the two datasets are searched for special situations in which the wind forcing and its orientation with respect to the coastline allowed the authors to deduce a mean sea ice compressive strength from simple theory. Many estimates of ice compressive strength were possible for the winter of 1992/93 when the Arctic high was confined to the western Arctic and deep penetration of the Icelandic low produced wind patterns that pushed the ice perpendicular to the coastline in the Beaufort and East Siberian Seas. The winter of 1996/97, on the other hand, was characterized by a well-established Arctic high, producing wind patterns that generally pushed ice along coastlines rather than against them. Results show lower and upper bounds on the sea ice compressive strength parameter of 30 and 40 kN m−2, and 35 and 45 kN m−2, for the winters of 1992/93 and 1996/97, respectively (with a potential bias low of about 10 kN m−2). A tensile strength for sea ice of about 25 kN m−2 is also found in the East Siberian Sea in the first few hundred kilometers from the land, presumably associated with land-fast ice. The proposed mean ice compressive strength estimate is higher than those derived by minimizing the cumulative error between simulated and observed buoy drift trajectories. It is noted that the uncertainties in the estimates derived from models are large (with an unbiased estimate of standard deviation of 8.75 kN m−2). The estimates of yield strength in isotropic compression presented herein are in good agreement with a previous estimate made during the Arctic Ice Dynamic Joint Experiment, and with in situ ice compressive stress measurements made in the Beaufort Sea.
Argon as a Tracer of Cross-Isopycnal Mixing in the Thermocline
Authors: Henning Cara C. , Archer David , Fung Inez
Published: December 2006

Noble gases such as argon are unaffected by chemical reactions in the ocean interior, but a number of physical mechanisms can lead to measurable sea level atmospheric disequilibrium in subsurface waters of the ocean. One such mechanism is the mixing of waters of different temperatures, which can lead to supersaturation in the ocean interior. The authors simulate the supersaturation mixing signature in the thermocline in a global ocean general circulation model, Parallel Ocean Program model, version 1.4 (POP 1.4). In contrast to existing mixing diagnostics such as dye tracers or microstructure measurements, which yield the local, recent rate of diabatic mixing, argon disequilibrium traces an integrated lifetime history of subsurface mixing. A theoretical model of the subtropical Atlantic Ocean gyre is built, based on the competing time scales of horizontal and vertical mixing, that agrees well with the full general circulation model argon supersaturation gradient in the thermocline. These results suggest that gyre-scale argon data from the real ocean could be similarly interpreted. The variation of the argon supersaturation with diffusivity in the equatorial Pacific Ocean is also investigated.
An Observational Estimate of Volume and Freshwater Flux Leaving the Arctic Ocean through Nares Strait
Authors: Münchow Andreas , Melling Humfrey , Falkner Kelly K.
Published: December 2006

The Arctic Ocean is an important link in the global hydrological cycle, storing freshwater and releasing it to the North Atlantic Ocean in a variable fashion as pack ice and freshened seawater. An unknown fraction of this return flow passes through Nares Strait between northern Canada and Greenland. Surveys of ocean current and salinity in Nares Strait were completed in the summer of 2003. High-resolution data acquired by ship-based acoustic Doppler current profiler and via hydrographic casts revealed subtidal volume and freshwater fluxes of 0.8 ± 0.3 Sv and –25 ± 12 mSv (Sv = 103 mSv = 106 m3 s−1), respectively. The observations resolved the dominant spatial scale of variability, the internal Rossby radius of deformation (LD ∼9 km), and revealed a complex, yet coherent along-channel flow with a Rossby number of about 0.13, close to geostrophic balance. Approximately one-third of the total volume flux was associated with across-channel slope of the sea surface and two-thirds (68%) with across-channel slope of isopycnal surfaces. During the period of observation, sustained wind from the southwest weakened the average down-channel flow at the surface. The speed of tidal currents exceeded subtidal components by a factor of 2. Tidal signals were resolved and removed from the observations here using two independent methods resolving horizontal and vertical variability of tidal properties, respectively. Tidal current predictions from a barotropic model agreed well with depth-averaged observations in both amplitude and phase. However, because estimates of freshwater flux require accurate surface currents (and salinity), a least squares fitting procedure using velocity data was judged more reliable, since it permits quantification of vertical tidal current variations.
Gulf Stream Variability in Five Oceanic General Circulation Models
Authors: de Coëtlogon Gaëlle , Frankignoul Claude , Bentsen Mats , Delon Claire , Haak Helmuth , Masina Simona , Pardaens Anne
Published: December 2006

Five non-eddy-resolving oceanic general circulation models driven by atmospheric fluxes derived from the NCEP reanalysis are used to investigate the link between the Gulf Stream (GS) variability, the atmospheric circulation, and the Atlantic meridional overturning circulation (AMOC). Despite the limited model resolution, the temperature at the 200-m depth along the mean GS axis behaves similarly in most models to that observed, and it is also well correlated with the North Atlantic Oscillation (NAO), indicating that a northward (southward) GS shift lags a positive (negative) NAO phase by 0–2 yr. The northward shift is accompanied by an increase in the GS transport, and conversely the southward shift with a decrease in the GS transport. Two dominant time scales appear in the response of the GS transport to the NAO forcing: a fast time scale (less than 1 month) for the barotropic component, and a slower one (about 2 yr) for the baroclinic component. In addition, the two components are weakly coupled. The GS response seems broadly consistent with a linear adjustment to the changes in the wind stress curl, and evidence for baroclinic Rossby wave propagation is found in the southern part of the subtropical gyre. However, the GS shifts are also affected by basin-scale changes in the oceanic conditions, and they are well correlated in most models with the changes in the AMOC. A larger AMOC is found when the GS is stronger and displaced northward, and a higher correlation is found when the observed changes of the GS position are used in the comparison. The relation between the GS and the AMOC could be explained by the inherent coupling between the thermohaline and the wind-driven circulation, or by the NAO variability driving them on similar time scales in the models.
Time-Dependent Response to Cooling in a Beta-Plane Basin
Authors: Pedlosky Joseph
Published: December 2006

The time-dependent response of an ocean basin to the imposition of cooling (or heating) is examined in the context of a quasigeostrophic, two-layer model on the beta plane. The focus is on the structure and magnitude of the vertical motion and its response to both a switch-on forcing and a periodic forcing. The model employed is a time-dependent version of an earlier model used to discuss the intensification of sinking in the region of the western boundary current. The height of the interface of the two-layer model serves as an analog of temperature, and the vertical velocity at the interface consists of a cross-isopycnal velocity modeled in terms of a relaxation to a prescribed interface height, an adiabatic representation of eddy thickness fluxes parameterized as lateral diffusion of thickness, and the local vertical motion of the interface itself. The presence of time dependence adds additional dynamical features to the problem, in particular the emergence of low-frequency, weakly damped Rossby basin modes. If the buoyancy forcing is zonally uniform the basin responds to a switch-on of the forcing by coming into steady-state equilibrium after the passage of a single baroclinic Rossby wave. If the forcing is nonuniform in the zonal direction, a sequence of Rossby basin modes is excited and their decay is required before the basin achieves a steady state. For reasonable parameter values the boundary layers, in which both horizontal and vertical circulations are closed, are quasi-steady and respond to the instantaneous state of the interior. As in the steady problem the flow is sensitive to small nonquasigeostrophic mass fluxes across the perimeter of the basin. These fluxes generally excite basin modes as well. The basin modes will also be weakly excited if the beta-plane approximation is relaxed. The response to periodic forcing is also examined, and the sensitivity of the response to the structure of the forcing is similar to the switch-on problem.
The Summertime Heat Budget and Circulation of Southeast New England Shelf Waters
Authors: Wilkin John L.
Published: December 2006

A modeling study of summer ocean circulation on the inner shelf south of Cape Cod, Massachusetts, has been conducted. The influences of winds, air–sea heat fluxes, tides, and shelfwide circulation are all incorporated. The model reproduces recognized features of the regional summer circulation: warm temperatures and weak eastward flow in Nantucket Sound, cool tidally mixed waters and an associated anticyclonic flow encircling the Nantucket Shoals, and strong stratification south of Martha’s Vineyard. Comparisons with satellite and in situ observations show the model simulates the major features of the temperature patterns that develop during summer 2002. The evolution of the summer heat budget is characterized by three regimes: Nantucket Sound heats rapidly in June and then maintains warm temperatures with little net air–sea heat flux; tidal mixing on the Nantucket Shoals maintains perpetually cool ocean temperatures despite significant air–sea heating; and midshelf south of Martha’s Vineyard the surface waters warm steadily through July and August because of sustained air–sea heating with only modest cooling resulting from the mean circulation. In the environs of the Martha’s Vineyard Coastal Observatory tidal eddy heat flux emanating from Nantucket Sound produces a bowl of warm water trapped against the coast and significant local variability in the net role of advection in the heat budget. A suite of idealized simulations with forcing dynamics restricted, in turn, to only one of winds, tides, or shelfwide inflows shows that tidal dynamics dominate the regional circulation.
Non-Gaussian Velocity Probability Density Functions: An Altimetric Perspective of the Mediterranean Sea
Authors: Isern-Fontanet Jordi , García-Ladona Emilio , Font Jordi , García-Olivares Antonio
Published: December 2006

Velocity probability density functions (PDFs) are a key tool to study complex flows and are of great importance to model particle dispersion. The PDFs of geostrophic velocities derived from sea level anomalies maps for the Mediterranean Sea have been computed and analyzed, guided by recent results found in studies of two-dimensional and geostrophic turbulence. At the basin scale results show that the geostrophic velocity PDF derived from SLA maps is non-Gaussian. To understand the origin of this non-Gaussianity, a topological partition of the flow based on the Okubo–Weiss parameter is applied to separate the contribution of coherent vortices from the background field. After such separation the non-Gaussian part of the PDF appears mostly associated with the presence of such structures. Only about 20% of the vortices identified in the dataset are mainly responsible for this deviation. These vortices, called intense vortices in previous works, are those vortices with values of the amplitude larger than or equal to two standard deviations of the Okubo–Weiss parameter and correspond to vortices with a radius on the order of 40 km.
Alongshore Wind Forcing of Coastal Sea Level as a Function of Frequency
Authors: Ryan Holly F. , Noble Marlene A.
Published: December 2006

The amplitude of the frequency response function between coastal alongshore wind stress and adjusted sea level anomalies along the west coast of the United States increases linearly as a function of the logarithm (log10) of the period for time scales up to at least 60, and possibly 100, days. The amplitude of the frequency response function increases even more rapidly at longer periods out to at least 5 yr. At the shortest periods, the amplitude of the frequency response function is small because sea level is forced only by the local component of the wind field. The regional wind field, which controls the wind-forced response in sea level for periods between 20 and 100 days, not only has much broader spatial scales than the local wind, but also propagates along the coast in the same direction as continental shelf waves. Hence, it has a stronger coupling to and an increased frequency response for sea level. At periods of a year or more, observed coastal sea level fluctuations are not only forced by the regional winds, but also by joint correlations among the larger-scale climatic patterns associated with El Niño. Therefore, the amplitude of the frequency response function is large, despite the fact that the energy in the coastal wind field is relatively small. These data show that the coastal sea level response to wind stress forcing along the west coast of the United States changes in a consistent and predictable pattern over a very broad range of frequencies with time scales from a few days to several years.
Location of the Antarctic Polar Front from AMSR-E Satellite Sea Surface Temperature Measurements
Authors: Dong Shenfu , Sprintall Janet , Gille Sarah T.
Published: December 2006

The location of the Southern Ocean polar front (PF) is mapped from the first 3 yr of remotely sensed Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) sea surface temperature (SST) measurements. In agreement with previous studies, the mean path of the Antarctic PF and its standard deviation are strongly influenced by bottom topography. However, the mean PF path diverges slightly from previous studies in several regions where there is high mesoscale variability. Although the SST and SST gradient at the PF show spatially coherent seasonal variations, with the highest temperature and the lowest temperature gradient during summer, the seasonal variations in the location of the PF are not spatially coherent. The temporal mean SST at the PF corresponds well to the mean PF path: the temperature is high in the Atlantic and Indian Ocean sections and is low in the Pacific Ocean section where the PF has a more southerly position. The relationship of the wind field with the Antarctic PF location and proxies for the zonal and meridional PF transports are examined statistically. Coherence analysis suggests that the zonal wind stress accelerates the zonal transport of the PF. The analysis presented herein also suggests that the meridional shifts of the Antarctic PF path correspond to the meridional shifts of the wind field.
Chalcedon Defended: A Pluralistic Re-Reading of the Two-Natures Doctrine
Authors: Schmidt-Leukel Perry
Published: December 2006

Is Christian belief in incarnation compatible with a pluralistic theology of religions? After a discussion of John Hick's criticism of Chalcedonian Christology the article argues that religious pluralism is not only compatible with, but could and should retain a form of incarnational thinking which preserves the essence of a double-nature teaching.
Choice is yours: A psychodynamic exploration of health policymaking and its consequences for the English National Health Service
Authors: Fotaki Marianna
Published: December 2006

Patient choice is at the forefront of the debate about the future of healthcare provision in many industrialized countries. It is argued that understanding the complexities and the multiple consequences involved in implementing individual patient choice in public health systems calls for an analytic framework extending beyond economic determinism and positivist social science paradigms. This study applies psychoanalytic concepts to illuminate policy dynamics and limitations, using the example of patient choice in the English NHS. It separates declared from unexpressed policy goals theorizing on the role of imaginary institutions and their defensive and less obvious functions in society, and reflects on the implications of policies that are formulated at a distance from operational reality on healthcare organizations. By focusing on the deeper primitive anxieties that are evoked and enacted in patient–doctor interactions, this article examines opportunities and limitations involved in developing individual patient choice.
Factors in team effectiveness: Cognitive and demographic similarities of software development team members
Authors: Kang Hye-Ryun , Yang Hee-Dong , Rowley Chris
Published: December 2006

The benefits of teams and teamwork are popular and propounded in management discourse. The use of this lexicon is based on beliefs in the resultant mutual gains for both organizations and individuals. Yet, are all teams, irrespective of the characteristics of membership composition, the same in terms of such beneficial outcomes? This study investigates the importance of team member characteristics, particularly cognitive and demographic, on team effectiveness and which characteristics matter more in team activities, especially where labour turnover is high, such as in software development. The Shared Mental Model is outlined and used as the representative construct for cognitive similarities; while age, tenure and gender are the demographic aspects used. From the relevant literature we develop a hypothesis and subject it to a range of tests based on empirical fieldwork using software development teams in South Korea. Our analysis shows that team effectiveness is more influenced by cognitive than demographic similarities. The implications and limitations of this work are detailed, with its wider relevance to international management, business and practice and other countries, noted.
Understanding the relationship between individualism–collectivism and team performance through an integration of social identity theory and the social relations model
Authors: Gundlach Michael , Zivnuska Suzanne , Stoner Jason
Published: December 2006

In studying the relationship between individualism–collectivism and team performance, empirical research has shown that individualistic team members exert a negative influence on team performance. However, theoretical understanding of why this relationship exists is lacking. Addressing this gap in the literature, this research proposes a theoretical model of the relationship between individualism–collectivism and team performance by integrating two previously distinct theories, social identity theory and the social relations model. Drawing upon these theories, we propose that team identification, meta-perception accuracy, and team identity will mediate the relationship between individualism–collectivism and team performance. Further, we posit that task interdependence will moderate the relationship between individualism–collectivism and team identifi-cation. In developing our work, we formulate testable propositions which are aligned with the specific relationships shown in our model. After presenting our model and propositions, we discuss the theoretical and practical implications of our work, and suggest areas for future research.
Highlighting a Link between the Gay-Berne Potential and the Boid Flocking Model
Authors: Scarle Simon
Published: December 2006

The author shows that the Gay-Berne potential, commonly used to describe such things as nematic liquid crystal systems, can be seen as equivalent to the boids model for simulating flocking and other collective motion behavior of various fauna.
Emergent Alternation in Complement Selection
Authors: Rudanko Juhani
Published: December 2006

This article examines the transitive into- ing pattern in current English with seven verbs of manner-neutral causation involving object control. It is argued that the usage is innovative. While the to infinitive pattern is still much more common, the article substantiates the existence of the transitive into- ing pattern with these verbs. Four of the seven verbs afford a noteworthy number of tokens in the material, and it is argued that with manner-neutral matrix verbs, the pattern is more frequent in British English than in American English at this time. The emergence of the pattern with such verbs is viewed as yet another manifestation of the more general spread of - ing complements at the expense of to infinitive complements. It is also argued that the distinctive semantic flavor of the transitive intoing pattern is also a factor aiding in its emergence.
Dancing composition: pedagogy and philosophy as experience
Authors: Gould Elizabeth
Published: December 2006

For philosopher Gilles Deleuze, the work of philosophy consists of affirmatively and artistically creating and reworking concepts in response to real-life problems in an ongoing process that invites new perspectives and ways of thinking. Carol Matthews's music composition pedagogical practices reflect these processes, arguing that they demonstrate the philosophical construct called ‘philosophy as experience.’ Through interaction – or dance – Matthews and her students in Primaries (grades K–1, approximately 5–7 years old) and Juniors (grades 2–3, approximately 8–10 years old) engage in philosophy by making informed, mindful musical decisions in response to lived musical problems in the material process of composing two songs, ‘Plants, Plants' by the Primaries and ‘Remembering Flight’ by the Juniors. Empirically enacting philosophy as experience, Matthews's practices and her students' responses reveal ways of thinking and being related to teaching and learning music composition that may inform the practices of other music educators and students, with implications for music teacher preparation.