Partially coupled spin-up of the MPI-ESM: implementation and first results

Large-scale fully coupled Earth system models (ESMs) are usually applied in climate projections like the IPCC (Intergovernmental Panel on Climate Change) reports. In these models internal variability is often within the correct order of magnitude compared with the observed climate, but due to internal variability and arbitrary initial conditions they are not able to reproduce the observed timing of climate events or shifts as for instance observed in the El Niño–Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), or the Atlantic Meridional Overturning Circulation (AMOC). Additional information about the real climate history is necessary to constrain ESMs; not only to emulate the past climate, but also to introduce a potential forecast skill into these models through a proper initialisation. We attempt to do this by extending the fully coupled climate model Max Planck Institute Earth System Model (MPI-ESM) using a partial coupling technique (Modini-MPI-ESM). This method is implemented by adding reanalysis wind-field anomalies to the MPI-ESM's inherent climatological wind field when computing the surface wind stress that is used to drive the ocean and sea ice model. Using anomalies instead of the full wind field reduces potential model drifts, because of different mean climate states of the unconstrained MPI-ESM and the partially coupled Modini-MPI-ESM, that could arise if total observed wind stress was used. We apply two different reanalysis wind products (National Centers for Environmental Prediction, Climate Forecast System Reanalysis (NCEPcsfr) and ERA-Interim reanalysis (ERAI)) and analyse the skill of Modini-MPI-ESM with respect to several observed oceanic, atmospheric, and sea ice indices. We demonstrate that Modini-MPI-ESM has a significant skill over the time period 1980–2013 in reproducing historical climate fluctuations, indicating the potential of the method for initialising seasonal to decadal forecasts. Additionally, our comparison of the results achieved with the two reanalysis wind products NCEPcsfr and ERAI indicates that in general applying NCEPcsfr results in a better reconstruction of climate variability since 1980

Determining North Atlantic meridional transport variability from pressure on the western boundary: a model investigation.

In this paper we investigate the possibility of determining North Atlantic meridional transport variability using pressure on the western boundary, focusing on the 42degN latitude of the Halifax WAVE array. We start by reviewing the theoretical foundations of this approach. Next we present results from a model analysis, both statistical and dynamic, that demonstrate the feasibility of the approach. We consider how well we can quantify the meridional transport variability at 42degN given complete knowledge of bottom pressure across the basin, and to what degree this quantification is degraded by first ignoring the effect of intervening topography, and then by using only bottom pressure on the western boundary. We find that for periods of greater than one year we can recover more than 90% of the variability of the main overturning cell at 42degN using only the western boundary pressure, provided we remove the depth-average boundary pressure signal. This signal arises from a basin mode of bottom pressure variability, which has power at all timescales, but that does not in truth have a meridional transport signal associated with it, and from the geostrophic depth-independent compensation of the Ekman transport. An additional benefit of the removal of the depth-average pressure is that this high-frequency Ekman signal, which is essentially noise as far as monitoring the MOC for climatically important changes is concerned, is clearly separated from other modes

Discontinuities in the late 1960's in different atmospheric data products

An analysis of the onset and spatial extent of discontinuities in the late 1960's in different atmospheric data products is performed. Discontinuities are found in both the NCEP/NCAR and ERA-40 reanalyses in various surface variables including sea level pressure (SLP) in both data sets over Africa, in the NCEP/NCAR reanalysis also over Asia and in the ERA-40 reanalysis also over South America, and precipitation in the NCEP/NCAR reanalysis over North Africa. Discontinuities are also found in 2 m air temperature in both reanalyses. The discontinuities in SLP extend into the lower troposphere. The main cause of these discontinuities appears to be missing or limited synoptic data prior to the late 1960's

A study of general practitioners' perspectives on electronic medical records systems in NHS Scotland

<b>Background</b> Primary care doctors in NHSScotland have been using electronic medical records within their practices routinely for many years. The Scottish Health Executive eHealth strategy (2008-2011) has recently brought radical changes to the primary care computing landscape in Scotland: an information system (GPASS) which was provided free-of-charge by NHSScotland to a majority of GP practices has now been replaced by systems provided by two approved commercial providers. The transition to new electronic medical records had to be completed nationally across all health-boards by March 2012. <p></p><b> Methods</b> We carried out 25 in-depth semi-structured interviews with primary care doctors to elucidate GPs' perspectives on their practice information systems and collect more general information on management processes in the patient surgical pathway in NHSScotland. We undertook a thematic analysis of interviewees' responses, using Normalisation Process Theory as the underpinning conceptual framework. <p></p> <b>Results</b> The majority of GPs' interviewed considered that electronic medical records are an integral and essential element of their work during the consultation, playing a key role in facilitating integrated and continuity of care for patients and making clinical information more accessible. However, GPs expressed a number of reservations about various system functionalities - for example: in relation to usability, system navigation and information visualisation. <b>Conclusion </b>Our study highlights that while electronic information systems are perceived as having important benefits, there remains substantial scope to improve GPs' interaction and overall satisfaction with these systems. Iterative user-centred improvements combined with additional training in the use of technology would promote an increased understanding, familiarity and command of the range of functionalities of electronic medical records among primary care doctors

On the width of the equatorial deep jets

The equatorial deep jets (EDJ) are a striking feature of the equatorial ocean circulation. In the Atlantic Ocean, the EDJ are associated with a vertical scale of between 300 and 700 m, a time scale of roughly 4.5 years and upward energy propagation to the surface. It has been found that the meridional width of the EDJ is roughly 1.5 times larger than expected based on their vertical scale. Here we use a shallow water model for a high order baroclinic vertical normal mode to argue that mixing of momentum along isopycnals can explain the enhanced width. A lateral eddy viscosity of 300 m2 s−1 10 is found to be sufficient to account for the width implied by observations

Current and Oxygen Variability in the Tropical North East Atlantic

The tropical North East Atlantic (TNEA) is characterized by an oxygen minimum zone (OMZ) that is located at intermediate depth (300m – 700m) and latitudinally spreads between the oxygen-rich equatorial Atlantic and the Cape Verde Frontal Zone at about 20°N. Recent studies have shown that local oxygen fluctuations and the associated ventilation of the TNEA OMZ are mainly caused by diapycnal mixing and mesoscale eddies. Zonal currents additionally ventilate the TNEA by advecting oxygen-rich water from the well-ventilated western boundary eastwards. The spatial and temporal variability of these zonal currents is thought to contribute to the oxygen variability in this regime. An intense measurement program along 23°W cutting through the TNEA OMZ has been executed during recent years. Moored observations and repeat ship sections were performed with CTD/O2 (conductivity, temperature, depth, oxygen) and current measurements. Here, we analyze the spatial and temporal variability of the zonal currents in the TNEA at intermediate depths and discuss their respective role for the spatial and temporal oxygen variability as well as the ventilation of the OMZ. Particularly, the observed annual cycle of the North Equatorial Undercurrent (NEUC) at 5°N, which is several cm/s at intermediate depth, causes phase-shifted (zonal velocity leading oxygen) annual oxygen fluctuations in a range of about 10 µmol/kg. In general, time-varying zonal currents advect oxygen eastwards that is meridionally redistributed by mesoscale eddies. The overall effect of those currents for the ventilation of the OMZ is discussed

A simple diagnostic based on sea surface height with an application to central Pacific ENSO

We use output from a freely running NEMO model simulation for the equatorial Pacific to investigate the utility of linearly removing the local influence of vertical displacements of the thermocline from variations in sea surface height. We show that the resulting time series of residual sea surface height, denoted ηnlti, measures variations in near-surface heat content that are independent of the local vertical displacement of the thermocline and can arise from horizontal advection, surface heat flux, and diapycnal mixing processes. We find that the variance of ηnlti and its correlation with sea surface temperature are focused on the Niño4 region. Furthermore, ηnlti averaged over the Niño4 region is highly correlated with indices of central Pacific El Niño–Southern Oscillation (CP ENSO), and its variance in 21-year running windows shows a strong upward trend over the past 50 years, corresponding to the emergence of CP ENSO following the 1976/77 climate shift. We show that ηnlti can be estimated from observations, using satellite altimeter data and a linear multi-mode model. The time series of ηnlti, especially when estimated using the linear model, show pronounced westward propagation in the western equatorial Pacific, arguing for an important role for zonal advective feedback in the dynamics of CP ENSO, in particular for cold events. We also present evidence that the role of the thermocline displacement in influencing sea surface height increased strongly after 2000 in the eastern part of the Niño4 region, at a time when CP ENSO was particularly active. Finally, the diagnostic is easy to compute and can be easily applied to mooring data or coupled climate models.</p

A Description of Local and Nonlocal Eddy–Mean Flow Interaction in a Global Eddy-Permitting State Estimate

The assumption that local baroclinic instability dominates eddy–mean flow interactions is tested on a global scale using a dynamically consistent eddy-permitting state estimate. Interactions are divided into local and nonlocal. If all the energy released from the mean flow through eddy–mean flow interaction is used to support eddy growth in the same region, or if all the energy released from eddies through eddy–mean flow interaction is used to feed back to the mean flow in the same region, eddy–mean flow interaction is local; otherwise, it is nonlocal. Different regions have different characters: in the subtropical region studied in detail, interactions are dominantly local. In the Southern Ocean and Kuroshio and Gulf Stream Extension regions, they are mainly nonlocal. Geographical variability of dominant eddy–eddy and eddy–mean flow processes is a dominant factor in understanding ocean energetics.Woods Hole Oceanographic InstitutionUnited States. National Aeronautics and Space Administration (Grant NNX09AI87G)United States. National Aeronautics and Space Administration (Grant NNX08AR33G

Systematically reviewing and synthesizing evidence from conversation analytic and related discursive research to inform healthcare communication practice and policy: an illustrated guide

Background Healthcare delivery is largely accomplished in and through conversations between people, and healthcare quality and effectiveness depend enormously upon the communication practices employed within these conversations. An important body of evidence about these practices has been generated by conversation analysis and related discourse analytic approaches, but there has been very little systematic reviewing of this evidence. Methods We developed an approach to reviewing evidence from conversation analytic and related discursive research through the following procedures: • reviewing existing systematic review methods and our own prior experience of applying these • clarifying distinctive features of conversation analytic and related discursive work which must be taken into account when reviewing • holding discussions within a review advisory team that included members with expertise in healthcare research, conversation analytic research, and systematic reviewing • attempting and then refining procedures through conducting an actual review which examined evidence about how people talk about difficult future issues including illness progression and dying Results We produced a step-by-step guide which we describe here in terms of eight stages, and which we illustrate from our ‘Review of Future Talk’. The guide incorporates both established procedures for systematic reviewing, and new techniques designed for working with conversation analytic evidence. Conclusions The guide is designed to inform systematic reviews of conversation analytic and related discursive evidence on specific domains and topics. Whilst we designed it for reviews that aim at informing healthcare practice and policy, it is flexible and could be used for reviews with other aims, for instance those aiming to underpin research programmes and projects. We advocate systematically reviewing conversation analytic and related discursive findings using this approach in order to translate them into a form that is credible and useful to healthcare practitioners, educators and policy-makers

Prospects for decadal prediction of the North Atlantic Oscillation (NAO)

For certain, but realizable, states of the thermohaline and wind driven circulation of the North Atlantic Ocean, we demonstrate the possibility of making statements regarding the likely range of values to be taken by the annual average of the NAO-index on time scales out to a decade. Given that the North Atlantic is currently in such a predictable state, a simple surrogate model yields a prediction that the NAO index is more likely to be positive than negative for the next couple of years, followed by several years in which the NAO index is more likely to be negative