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An idealized coupled ocean–atmosphere model is utilized to study the influence of horizontal resolution and parameterized eddy processes on the thermohaline circulation. A series of experiments ranging from 4° to 0.25° resolution, with appropriate horizontal viscosities and diffusivities in each case, is performed for both coupled and ocean-only models. Spontaneous internal variability (primarily on the decadal timescale) is found to exist in the higher-resolution cases (with the exception of one of the restoring experiments). The decadal oscillation (whose period varies slightly between cases) is described as an advective–convective mechanism that is thermally driven and linked to the value of the horizontal diffusivity utilized in the model. Increasing the diffusivity in the high-resolution cases presented in this paper is enough to destroy the variability, whereas decreasing the diffusivity in the moderately coarse-resolution cases is capable of inducing decadal-scale variability. As the resol...

The Intergovernmental Panel on Climate Change (IPCC) recently published its second scientific assessment of climate change. Central to the findings of this study is the statement that “the balance of evidence suggests a discernible human influence on global climate”. This statement arose from recent studies which compared the observational record over the last century with the results from numerical modelling simulations of the climatic response to increasing greenhouse gases and anthropogenic sulphate aerosols. It has profound implications for policy makers as it is the first time that IPCC has stated that global warming has been detected in the observational record. Recent modelling studies reported in the IPCC second assessment also suggest “best estimates” of 2°C warming and 50 cm sea level rise by the year 2100, relative to 1990, with amplification of the warming at high latitudes and over the interior of continents. Similar IPCC “best estimates” of emission scenarios suggest that the atmospheric concentration of carbon dioxide will continue to increase over the next few centuries. Stabilization of atmospheric carbon dioxide levels, even as high as three times the present, require emission levels significantly below those of 1990. In this paper, the observational record is briefly reviewed as are the recent modelling results which have lead to the statements above. Particular emphasis is given to the role of the oceans in climate change and climate variability. By appealing to the paleoclimatic record for analogies of a climate warmed through anthropogenic greenhouse gases, a discussion of potential climatic swings and regime changes is presented. The policy implications of this work are also addressed.

A review of quantitative research studies published between 1991 and 1995 in 3 major mental health nursing journals revealed that approximately 10% (31 of 311) included a measure of religion or spirituality. This percentage (10%) is 3 to 8 times higher than that found in previous reviews of empirical research in psy chological and psychiatric journals, suggesting that mental health nursing research is more sensitive to the role of religious-spiritual factors on mental health than research in related disciplines. The results are discussed in the context of the history and philosophy of nursing and in comparison to related disciplines. Methodological aspects of the research, especially the importance of multiple measures, are discussed, as are other salient findings.

In this paper we use a novel empirical strategy to estimate the net benefit of regulatory restrictions on the supply of fringe credit products. Our estimation measures the effect of strict regulation and prohibition of one such product — payday loans — on demand for another product — refund anticipation loans (RALs). Using a policy discontinuity at state border approach with zip-code-level panel data, we find an economically and statistically significant negative effect of strict regulation of payday loans on demand for RALs. A state ban on payday lending results in about five percent reduction in demand for RALs. We interpret this effect as evidence that the behavioral component is stronger than the rational-strategic component of demand for payday loans, indicating that strict regulation of payday loans may benefit households on net. We conclude with a discussion of implications for policy.

The effect of employing flux adjustments on the climatic response of an idealized coupled model to an imposed radiative forcing is investigated with two coupled models, one of which employs flux adjustments. A linear reduction (to the planetary longwave flux) of 4 W/m2 is applied over a 70 y period and held constant thereafter. Similar model responses are found (during the initial 70 y period) for global-scale diagnostics of hemispheric air temperature due to the nearly linear surface-air temperature response to the radiative forcing. Significant regional scale differences do exist, however. As the perturbation away from the present climate grows, basin-scale diagnostics (such as meridional overturning rates) begin to diverge between flux adjusted and non-flux adjusted models. Once the imposed radiative forcing is held constant, differences in global mean air temperature of up to 0.5 °C are found, with large regional-scale differences in air temperature and overturning rates within the North Atlantic and Southern Ocean. Two additional experiments with the flux adjusted model (beginning from points further along the control integration) suggest that the elimination of much of the coupling shock before the radiative forcing is applied leads to results slightly closer to the non-flux adjusted case, although large differences still persist. In particular a dipole structure indicating an enhanced warming within the Pacific sector of the Southern Ocean, and cooling within the Atlantic sector is not reproduced by the flux adjusted models. This disparity is intimately linked to the Southern Ocean overturning cell along with the flux adjustments employed as well as the drift arising from coupling shock. If a similar form of sensitivity exists in more realistic coupled models, our results suggest: (1) perturbation experiments should not be undertaken until after the coupled model control experiment is carried out for several hundred years (thereby minimizing the coupling shock); (2) care should be exercised in the interpretation of regional-scale results (over the ocean) in coupled models which employ flux adjustments; (3) care should also be taken in interpreting even global-scale diagnostics in flux adjusted models for large perturbations about the present climate.

An idealized coupled ocean–atmosphere model is utilized to study the influence of horizontal resolution and parameterized eddy processes on the poleward heat transport in the climate system. A series of experiments ranging from 4° to 0.25° resolution, with appropriate horizontal viscosities and diffusivities in each case, are performed. The coupled atmosphere–ocean model results contradict earlier studies, which showed that the heat transport associated with time-varying circulations counteracted increases in the time mean so that the total remained unchanged as resolution was increased. Even though the total oceanic heat transport has not converged, the net planetary heat transport has essentially converged owing to the strong constraint of energy balance at the top of the atmosphere. Consequently, the atmospheric heat transport is reduced to offset the increasing oceanic heat transport. To interpret these results, the oceanic heat transport is decomposed into its baroclinic overturning (related...

The temporal and geographical roles of meltwater discharge (from the Laurentide ice sheet) on North Atlantic Deep Water (NADW) production are investigated utilizing a global, realistic geometry, coupled climate model which does not require the use of flux adjustments. Model results suggest that preconditioning by meltwater discharge (to the Mississippi) prior to the Younger Dryas (YD) is capable of pushing NADW beyond the limit of its sustainability. The diversion of meltwater to the St. Lawrence then merely serves to completely inhibit NADW production. The modeled change in surface air temperature generally agrees with the global pattern and magnitude of temperature change seen in paleoclimatic reconstructions of the YD and is intimately linked to changes in NADW formation. The global thermohaline circulation provides an interhemispheric teleconnection with the Southern Oceans, while changes in the atmospheric heat transport (reacting to a global redistribution of oceanic heat transport) provide a mechanism for interbasin teleconnection. Although the primary thermodynamic and hydrological cycle feedback processes are included within the atmospheric model, in the absence of additional feedbacks an equilibrium without the presence of NADW is possible. The inclusion of the wind stress/speed feedback is found to significantly contribute to the resumption of NADW production, as suggested by previous studies. Contrary to these same studies, however, the coupled model indicates an advective spin-up timescale is required for resumption of NADW production and hence the termination of the modeled YD-like climate event (as opposed to a decadal-century timescale). The reason for the discrepancy is unclear but may be associated with the use of fixed salt flux fields applied in previous studies, or the duration, strength, and geographical location of the imposed meltwater applied.

The results from ocean model experiments conducted with isopycnal and isopycnal thickness diffusion parameterizations for subgrid-scale mixing associated with mesoscale eddies are examined from a numerical standpoint. It is shown that when the mixing tensor is rotated, so that mixing is primarily along isopycnals, numerical problems may occur and non-monotonic solutions, which violate the second law of thermodynamics, may arise when standard centered difference advection algorithms are used. These numerical problems can be reduced or eliminated if sufficient explicit (unphysical) background horizontal diffusion is added to the mixing scheme. A more appropriate solution is the use of more sophisticated numerical advection algorithms, such as the flux- corrected transport algorithm. This choice of advection scheme adds additional mixing only where it is needed to preserve monotonicty and so retains the physically desirable aspects of the isopycnal and isopycnal thickness diffusion parameterizations...

The paleoclimatic effects of the closure of the Isthmus of Panama ∼3 Ma are investigated using a coupled atmosphere-ocean model. Consistent with earlier ocean-only modelling studies, it is shown that prior to closure there is an absence of deep water formation in the North Atlantic. Hence there is a reduction in oceanic heat transport. This is largely compensated for by the atmosphere such that only small changes in total planetary heat transport occur. The model climate of the North Atlantic is significantly warmer after Isthmus closure. In addition, the regions surrounding the Pacific Ocean and South Atlantic are generally cooler while the Indian Ocean is generally warmer in the model present-day climate. Finally, possible relationships to glaciation and initiation of northern hemisphere glacial cycles are discussed.

This article addresses the issue of the need for clergy to be better informed regarding the assessment of child abuse and neglect. It provides a quick reference guide to assist clergy in assessing the risk factors in the abusive family with guidelines for the recognition of child maltreatment. In a society that is marked by unprecedented levels of child maltreatment reporting and an ever increasing shortage of mental health services, clergy are increasingly being confronted by situations involving potential child maltreatment that require expert crisis intervention skills. This article provides specific, concrete guidelines for clergy confronted with situations that call for the recognition of child maltreatment.

Both historical and idealized climate model experiments are performed with a variety of Earth system models of intermediate complexity (EMICs) as part of a community contribution to the Intergovernmental Panel on Climate Change Fifth Assessment Report. Historical simulations start at 850 CE and continue through to 2005. The standard simulations include changes in forcing from solar luminosity, Earth's orbital configuration, CO[subscript 2], additional greenhouse gases, land use, and sulphate and volcanic aerosols. In spite of very different modelled pre-industrial global surface air temperatures, overall 20th century trends in surface air temperature and carbon uptake are reasonably well simulated when compared to observed trends. Land carbon fluxes show much more variation between models than ocean carbon fluxes, and recent land fluxes appear to be slightly underestimated. It is possible that recent modelled climate trends or climate–carbon feedbacks are overestimated resulting in too much land carbon loss or that carbon uptake due to CO[subscript 2] and/or nitrogen fertilization is underestimated. Several one thousand year long, idealized, 2 × and 4 × CO[subscript 2] experiments are used to quantify standard model characteristics, including transient and equilibrium climate sensitivities, and climate–carbon feedbacks. The values from EMICs generally fall within the range given by general circulation models. Seven additional historical simulations, each including a single specified forcing, are used to assess the contributions of different climate forcings to the overall climate and carbon cycle response. The response of surface air temperature is the linear sum of the individual forcings, while the carbon cycle response shows a non-linear interaction between land-use change and CO[subscript 2] forcings for some models. Finally, the preindustrial portions of the last millennium simulations are used to assess historical model carbon-climate feedbacks. Given the specified forcing, there is a tendency for the EMICs to underestimate the drop in surface air temperature and CO[subscript 2] between the Medieval Climate Anomaly and the Little Ice Age estimated from palaeoclimate reconstructions. This in turn could be a result of unforced variability within the climate system, uncertainty in the reconstructions of temperature and CO[subscript 2], errors in the reconstructions of forcing used to drive the models, or the incomplete representation of certain processes within the models. Given the forcing datasets used in this study, the models calculate significant land-use emissions over the pre-industrial period. This implies that land-use emissions might need to be taken into account, when making estimates of climate–carbon feedbacks from palaeoclimate reconstructions.

An atmospheric model incorporating energy and moisture balance equations is developed for use in process studies of the climate system. Given the sea surface temperature and specified surface wind field, the atmospheric model calculates the surface fields of air temperature, specific humidity, as well as heat and freshwater fluxes. The inclusion of the moisture balance in the atmospheric model allows the effects of latent heat transport to be included explicitly in the model. Under fixed climatological sea surface temperature (SST) and surface wind conditions, surface air temperatures, specific humidities, and surface fluxes are comparable to direct estimates. Precipitation compares less favorably with observations. As an extension to the climatological forcing case, we conduct a simple perturbation experiment in which the 1955–1959 pentad is compared to the 1970–1974 pentad by driving the model under the respective SST fields. The model exhibits a global air temperature decrease in the latter pentad of 0.27°C (comparable to direct estimates) with cooling in the northern hemisphere and warming in the southern hemisphere. Such large-scale cooling in our atmospheric model is driven by equivalent local changes in the prescribed SST fields, subsequently smoothed by atmospheric diffusion of heat. The interpentadal modeled differences are shown to be quite robust through model experiments using parameters representative of several different unrealistic climatologies. The resulting interpentadal difference fields change remarkably little even when the background state has changed dramatically. This emphasizes the almost linear response of the atmospheric model to the imposed SST changes. The atmospheric model is also coupled to an ocean general circulation model without the need for flux adjustments. This coupled climate model faithfully represents deep water formation in the North Atlantic and Southern Ocean, with upwelling throughout the Pacific and Indian Oceans. Water mass characteristics in the vertical compare very favorably with direct observations.

A diagnostic, finite element, barotropic ocean model has been used to simulate the mean circulation in the North Atlantic. With the inclusion of the joint effect of baroclinicity and relief (JEBAR), the Gulf Stream is found to separate at the correct latitude, ∼35°N, off Cape Hatteras. Results suggest that the JEBAR term in three key regions (offshore of the separation point in the path of the main jet, along the slope region of the North Atlantic Bight, and in the central Irminger Sea) is crucial in determining the separation point. The transport driven by the bottom pressure torque component of JEBAR dominates the solution, except in the subpolar gyre, and is also responsible for the separation of the Gulf Stream. Excluding high latitudes (in the deep-water formation regions) density variations in the upper 1000 m of the water column govern the generation of the necessary bottom pressure torque in our model. Examination of results from the World Ocean Circulation Experiment-Community Modelling ...

A simple surface boundary condition that allows evaporation to depend on sea surface temperature is developed for use in uncoupled ocean models. A positive feedback with the thermohaline circulation is produced, whereby accelerated overturning warms the high latitudes by advection, increasing evaporation and hence the sea surface salinity, which then feeds back upon the overturning circulation. Nonlinear interaction with convection complicates the response in some cases; however, in general the time-dependent component of the evaporation tends to be small so that the evolution is similar between parallel experiments with SST-dependent evaporation and under fixed freshwater fluxes. In agreement with this, two examples with internal variability of the thermohaline circulation on decadal and millennial timescales respectively are not fundamentally altered under the new feedback compared to the control runs under mixed boundary conditions, although both the period and the duration of the variability ...

The surface heat and freshwater fluxes from equilibrium ocean (OGCM) and atmospheric (AGCM) general circulation model climates are examined in order to determine the minimum flux adjustment required to prevent climate drift upon coupling. This is accomplished by integrating an OGCM with specified surface fluxes. It is shown that a dramatic climate drift of the coupled system is inevitable unless ocean meridional heat and freshwater (salt) transports are used as constraints for tuning the AGCM present-day climatology. It is further shown that the magnitude of the mismatch between OGCM and AGCM fluxes is not as important for climate drift as the difference in OGCM and implied AGCM meridional heat and freshwater (salt) transports. Hence a minimum flux adjustment is proposed, which is zonally-uniform in each basin and of small magnitude compared to present flux adjustments. This minimum flux adjustment acts only to correct the AGCM implied oceanic meridional transports of heat and freshwater (salt). A slight extension is also proposed to overcome the drift in the surface waters when the minimum flux adjustment is used. Finally, it is suggested that the flux adjustments which arise from current methods used to determine them are all very similar, leading to adjustment fields which are significantly larger than both AGCM and climatological fields over large regions.

A finite element diagnostic model is used to study the circulation of the North Pacific Ocean. With the inclusion of the JEBAR term, the model produces a realistic picture of the circulation. All major currents are reproduced with the calculated transports agreeing well with observations. The three dimensional velocity structure is diagnosed from the thermal wind equation, assuming a reference velocity at the bottom. This bottom reference velocity is calculated from the Ekman, thermohaline and total transport (from the finite element model) velocities. The diagnosed velocity fields are then compared with a number of observational sections. The effect of using different wind stress climatologies is also examined. Because of the dominance of the JEBAR term in the solution, the resulting circulations are all similar. Analysis of the seasonal cycle in the model supports the suggestion of Sakamoto and Yamagata that JEBAR rectification can explain the decreased amplitude of the seasonal cycle and the out-of-phase relationship between observations and the predictions of flat-bottomed Sverdrup theory. Finally, density fields from 1955–1959 and 1970–1974 are used to examine aspects of interpentadal variability in the North Pacific Ocean.

There is a popular notion in the media that human-induced global warming will result in the onset of a new ice age. In their Perspective, Weaver and Hillaire-Marcel refute this view, explaining that global warming is unlikely to dramatically alter the North Atlantic ocean circulation. They also emphasize that elevated levels of atmospheric carbon dioxide lead to summer temperatures that do not allow glacier formation and growth.

In this article, the author uses a unique identification strategy along with credit proxy variables in a national data set to test whether credit status reveals information about an employee’s character that is predictive of employee productivity. Many employers screen new hires by examining the credit reports of job applicants. The practice has sparked debate, with opponents asserting that it amounts to discrimination and proponents maintaining that it is an important tool by which employers can ensure the quality of new employees. To date, little evidence exists on the validity of credit status as a screening device. The issue is complicated both by the lack of available data and by the difficulty in establishing causality. Results indicate that the character-related portion of credit status is not a significant predictor of worker productivity.

Three sub-grid-scale mixing parameterizations (lateral/vertical; isopycnal; Gent and McWilliams, 1990) are used in a global ocean model in an attempt to determine which yields the best ocean climate. Observed CFC-11 distributions, in both the North and South Atlantic, are used in evaluating the model results. While the isopycnal mixing scheme does improve the deep ocean potential temperature and salinity distributions, when compared to results from the traditional lateral/vertical mixing scheme, the CFC-11 distribution is worse in the upper ocean due to too much mixing. The Gent and McWilliams (1990) parameterization significantly improves the CFC-11 distributions when compared to both of the other schemes. The main improvement comes from a reduction of CFC uptake in the southern ocean where the ‘bolus’ transport cancels the mean advection of tracers and hence causes the Deacon Cell to disappear. These results suggest that the asymmetric response found in CO2-increase experiments, whereby the climate over the southern ocean does not warm as much as in the northern hemisphere, may be due to the particular mixing schemes used.

The statistical relationships between various components of the subpolar North Atlantic air-sea-ice climate system are reexamined in order to investigate potential processes involved in interdecadal climate variability. It is found that sea surface temperature anomalies concentrated in the Labrador Sea region have a strong impact upon atmospheric sea level pressure anomalies over Greenland, which in turn influence the transport of freshwater and ice anomalies out of the Arctic Ocean, via Fram Strait. These freshwater and ice anomalies are advected around the subpolar gyre into the Labrador Sea affecting convection and the formation of Labrador Sea Water. This has an impact upon the transport of North Atlantic Current water into the subpolar gyre and thus, also upon sea surface temperatures in the region. An interdecadal negative feedback loop is therefore proposed as an internal source of climate variability within the subpolar North Atlantic. Through the lags associated with the correlations between different climatic components, observed horizontal advection time scales, and the use of Boolean delay equation models, the time scale for one cycle of this feedback loop is determined to have a period of about 21 years.

The semi-Lagrangian adveation scheme is applied to the meridional-plane model of the thermohaline circulation developed by Marotzke et al., whose governing equations are solved under a variety of boundary conditions. To determine the extent to which the accuracy and efficiency of the calculations depends on the numerical integration scheme, the test problem is solved independently using an explicit finite-difference (leapfrog in time, centered difference in space) method and three implicit methods: a finite difference, a finite element, and an upwind scheme. Integrations of the model to several equilibria are performed to determine the accuracy, efficiency, and stability of each integration scheme as a function of time step. For the same level of accuracy the time step used in the semi-Lagrangian scheme is found to be at least five times greater than that employed in the case of the implicit methods. The time step used in the implicit methods in turn are at least six times greater than those need...

The finite-element method possesses many advantages over more traditional numerical techniques used to solve systems of differential equations. These advantages include a number of conservation properties and a natural treatment of boundary conditions. The method's piecewise nature makes it useful when dealing with irregular domains and similarly when using variable horizontal resolution. To take advantage of these properties, a finite-element representation of the linearized, steady-state, barotropic potential vorticity equation is developed. The Stommel problem is used as an initial test for the model. A fourth-order eddy viscosity term is then added, and the resulting problem is solved in both simply and multiply connected domains under both slip and no-slip boundary conditions. The beta-plane assumption is then relaxed, and the model is reformulated in spherical coordinates. A realistic geography and topography version of this model is also used to examine the barotropic circulation in the No...

Addresses the issue that parish-based clergy, functioning as frontline community mental health workers, often do so with inadequate training and limited support from the mental health community. Claims that although a clergyperson is as likely to have a severely mentally distressed person seek her or his assistance as is a mental health specialist, there is inadequate research on the function of clergy in the mental health network or the psychological dynamics of religion. Suggests that clergy can serve most effectively in the mental health network as skilled facilitators, identifying the needs of persons, and connecting them to a larger circle of specialized helpers. Argues that the mental health and religious communities share many common values and goals and need to work together more effectively for the best interest of those they are called to serve.

The stability of an idealized climate system is investigated using a simple coupled atmosphere-ocean box model. Motivated by the results from general circulation models, the main physical constraint imposed on the system is that the net radiation at the top of the atmosphere is fixed. The specification of an invariant equatorial atmospheric temperature, consistent with paleoclimatic data, allows the hydrological cycle to be internally determined from the poleward heat transport budget, resulting in a model that has a plausible representation of the hydrological cycle-thermohaline circulation interaction. The model suggests that the stability and variability of the climate system depends fundamentally on the mean climatic state (total heat content of the system). When the total heat content of the climate system is low, a stable present-day equilibrum exists with high-latitude sinking. Conversely, when the total heat content is high, a stable equatorial sinking equilibrium exists. For a range of intermediate values of the total heat content, internal climatic oscillations can occur through a hydrological cycle-thermohaline circulation feedback process. Experiments conducted with the model reveal that under a 100-year 2 × CO2 warming, the thermohaline circulation first collapses but then recovers. Under a 100-year 4 × CO2 warming, the thermohaline circulation collapses and remains collapsed. Recent paleoclimatic data suggest that the climate system may behave very differently for a warmer climate. Our results suggest that this may be attributed to the enhanced poleward freshwater transport, which causes increased instability of the presentday thermohaline circulation.

From the *American Red Cross, New York, New York; †The HealthCareChaplaincy, New York, New York; ‡The Traumatology Institute in theSchool of Social Work, Florida State University, Tallahassee, Florida.Send reprint requests to Rabbi Roberts, c/o HCC 307 E. 60th Street, NYC, NY10022Copyright © 2003 by Lippincott Williams & WilkinsDOI: 10.1097/01.nmd.0000095129.50042.30

This exploratory study was designed to examine how players make moral choices in video games and what effects these choices have on emotional responses to the games. Participants (n=75) filled out a moral foundations questionnaire (MFQ) and then played through the first full act of the video game Fallout 3. Game play was recorded and content analyzed for the moral decisions made. Players also reported their enjoyment of and emotional reactions to the game and reflected on the decisions they made. The majority of players made moral decisions and behaved toward the nonplayer game characters they encountered as if these were actual interpersonal interactions. Individual differences in decision making were predicted by the MFQ. Behaving in antisocial ways did increase guilt, but had no impact on enjoyment.

Both historical and idealized climate model experiments are performed with a variety of Earth system models of intermediate complexity (EMICs) as part of a community contribution to the Intergovernmental Panel on Climate Change Fifth Assessment Report. Historical simulations start at 850 CE and continue through to 2005. The standard simulations include changes in forcing from solar luminosity,Earth’s orbital configuration, CO2, additional greenhouse gases, land use, and sulphate and volcanic aerosols. In spite of very different modelled pre-industrial global surface air temperatures, overall 20th century trends in surface air temperature and carbon uptake are reasonably well simulated when compared to observed trends. Land carbon fluxes show much more variation between models than ocean carbon fluxes, and recent land fluxes appear to be slightly underestimated. It is possible that recent modelled climate trends or climate–carbon feedbacks are overestimated resulting in too much land carbon loss or that carbon uptake due to CO2 and/or nitrogen fertilization is underestimated. Several one thousand year long, idealized, 2× and 4×CO2 experiments are used to quantify standard model characteristics,including transient and equilibrium climate sensitivities, and climate–carbon feedbacks. The values from EMICs generally fall within the range given by general circulation models. Seven additional historical simulations, each including a single specified forcing, are used to assess the contributions of different climate forcings to the overall climate and carbon cycle response. The response of surface air temperature is the linear sum of the individual forcings, while the carbon cycle response shows a non-linear interaction between land-use change and CO2 forcings for some models. Finally, the preindustrial portions of the last millennium simulations are used to assess historical model carbon-climate feedbacks. Given the specified forcing, there is a tendency for the EMICs to underestimate the drop in surface air temperature and CO2 between the Medieval Climate Anomaly and the Little Ice Age estimated from palaeoclimate reconstructions. This in turn could be a result of unforced variability within the climate system, uncertainty in the reconstructions of temperature and CO2, errors in the reconstructions of forcing used to drive the models, or the incomplete representation of certain processes within the models. Given the forcing datasets used in this study, the models calculate significant land-use emissions over the pre-industrial period. This implies that landuse emissions might need to be taken into account, when making estimates of climate–carbon feedbacks from palaeoclimate reconstructions

The evolution of the Atlantic Meridional Overturning Circulation (MOC) in 30 models of varying complexity is examined under four distinct Representative Concentration Pathways. The models include 25 Atmosphere-Ocean General Circulation Models (AOGCMs) or Earth System Models (ESMs) that submitted simulations in support of the 5th phase of the Coupled Model Intercomparison Project (CMIP5) and 5 Earth System Models of Intermediate Complexity (EMICs). While none of the models incorporated the additional effects of ice sheet melting, they all projected very similar behaviour during the 21st century. Over this period the strength of MOC reduced by a best estimate of 22% (18%-25%; 5%-95% confidence limits) for RCP2.6, 26% (23%-30%) for RCP4.5, 29% (23%-35%) for RCP6.0 and 40% (36%-44%) for RCP8.5. Two of the models eventually realized a slow shutdown of the MOC under RCP8.5, although no model exhibited an abrupt change of the MOC. Through analysis of the freshwater flux across 30 degrees-32 degrees S into the Atlantic, it was found that 40% of the CMIP5 models were in a bistable regime of the MOC for the duration of their RCP integrations. The results support previous assessments that it is very unlikely that the MOC will undergo an abrupt change to an off state as a consequence of global warming. Citation: Weaver, A. J., et al. (2012), Stability of the Atlantic meridional overturning circulation: A model intercomparison, Geophys. Res. Lett., 39, L20709, doi:10.1029/2012GL053763.

This study was designed to investigate the comparative ego development, religious orientation, and doctrinal beliefs of three Protestant groups: life-long fundamentalists (n=25), fundamentalist converts (n=25), and nonfundamentalist converts (n=25). Subjects from the Southern Baptist Church (fundamentalists) and United Methodist Church (nonfundamentalists) were used. Three instruments were employed: the Wiggins Content Scale of Religious Fundamentalism from the Minnesota Multiphasic Personality Inventory, Loevinger's Washington University Sentence Completion Test of Ego Development, and Allport's Religious Orientation Scale. The fundamentalist and nonfundamentalist groups were doctrinally different; however, the groups did not differ in levels of ego development. The two fundamentalist groups scored higher on Allport's measure of intrinsic religious orientation. Methodological suggestions were made for future research of fundamentalists.

An ocean general circulation model is used to examine the role of model geometry and surface buoyancy and wind stress forcing in the asymmetry of the global thermohaline circulation. The model domain is a highly idealized Atlantic and Pacific, linked by a circumpolar ocean in the south, and the integrations are performed under mixed boundary conditions diagnosed from spinups under various temperature and salinity profiles constructed from the present-day climatology. The model exhibits a tendency to favor either a “conveyor”-type circulation with sinking in the northern North Atlantic and upwelling in the North Pacific, or a “southern sinking” state with deep sinking in the Antarctic only. This bias is not dictated solely by the hydrological cycle, nor apparently by the greater northern extension of the Atlantic basin, but presumably by the overall asymmetry of the geometry. Equilibria with northern sinking in both basins can appear, however, when the winds in the Southern Ocean are reduced or th...

RECENT data from the GRIP ice core1–3 in Greenland suggest that the climate of the last (Eemian) interglacial period was much less stable than that of the present interglacial. Rapid transitions between warm and cold periods were found to occur on timescales of just a few decades. The North Atlantic climate during the Eemian period was also shown to be characterized by three states, respectively warmer than, similar to and colder than today1,2. Recent data from the nearby GISP2 ice core have revealed some discrepancies with these findings, which remain to be resolved4,5. Here we present simulations using an idealized global ocean model, which suggest that the North Atlantic ocean has three distinct circulation modes, each of which corresponds to a distinct climate state. We find that adding a simple random component to the mean freshwater flux (which forces circulation) can induce rapid transitions between these three modes. We suggest that increased variability in the hydrological cycle associated with the warmer Eemian climate could have caused transition between these distinct modes in the North Atlantic circulation, which may in turn account for the apparent rapid variability of the Eemian climate.

A simple interhemispheric ocean model is used to examine the sensitivity of water sinking in the northern hemisphere to the equator-to-pole density contrast. The model assumes that the sinking is compensated by upwelling in both the low latitude ocean and the Southern Ocean. We compare two vertical mixing schemes: one with a fixed vertical diffusivity and another with fixed mixing energy. The latter case implies that the vertical diffusivity depends on the simulated oceanic circulation. It is shown that when Southern Ocean upwelling is controlled only by northward Ekman transport, the rate of deep water formation has an opposite dependence on the equator-to-pole density contrast between the two vertical mixing schemes. However, when Southern Ocean upwelling is controlled by both Ekman transport and strong enough eddy-induced transport across the Antarctic Circumpolar Current, the two mixing schemes give qualitatively similar dependence: the rate of water sinking increases with the equator-to-pole density contrast, regardless of whether the diffusivity or the mixing energy is held fixed. It is suggested that the ACC eddies and vertical mixing jointly control the response of the overturning circulation to changes in the equator-to-pole density contrast. DOI: 10.1034/j.1600-0870.2003.201518.x

Implementing oxygen isotopes (H218O, H216O) in coupled climate models provides both an important test of the individual model's hydrological cycle, and a powerful tool to mechanistically explore past climate changes while producing results directly comparable to isotope proxy records. Here we describe the addition of oxygen isotopes in the University of Victoria Earth System Climate Model (UVic ESCM). Equilibrium simulations are performed for preindustrial and Last Glacial Maximum conditions. The oxygen isotope content in the model preindustrial climate is compared against observations for precipitation and seawater. The distribution of oxygen isotopes during the LGM is compared against available paleo-reconstructions.

This article addresses the need for clergy to be better informed regarding the assessment and treatment of “post-traumatic stress disorder” (PTSD), and provides a quick reference guide to assist clergy in the recognition of PTSD with guidelines for interventions. In a society that is marked by unprecedented levels of violence and a growing shortage of mental health services, clergy are increasingly confronted with situations involving psychological trauma that require expert crisis intervention skills. This article provides specific, concrete guidelines for clergy confronted with situations that require knowledge about PTSD.

The existing research on the appeal of media violence has led to an apparent incongruity: violent content tends to increase selective exposure to media, but violence often decreases enjoyment. In this experiment, we used two independent manipulations to assess the role of violence in both selective exposure and enjoyment in order to examine the relationship between the two. Program descriptions for four prime-time television dramas were altered to create violent and nonviolent descriptions for each episode. Then the episodes themselves were edited to create violent and nonviolent versions of each. Participants (N = 191) were more likely to choose violent descriptions to watch, but enjoyed the nonviolent episodes more than the violent episodes. Moreover, the nonviolent episodes were rated as more enjoyable even when the participants had chosen to watch a violent program description. From a theoretical perspective, these results suggest the need to move beyond explaining the appeal of violence in terms of increased enjoyment and instead further explore other motivations that could be driving selective exposure to violent content.