Can the last glacial maximum constrain climate sensitivity?

We investigate the relationship between the Last Glacial Maximum (LGM) and climate sensitivity across the PMIP2 multi-model ensemble of GCMs, and find a correlation between tropical temperature and climate sensitivity which is statistically significant and physically plausible. We use this relationship, together with the LGM temperature reconstruction of Annan and Hargreaves [2012], to generate estimates for the equilibrium climate sensitivity. We estimate the equilibrium climate sensitivity to be about 2.5C with a high probability of being under 4C, though these results are subject to several important caveats. The forthcoming PMIP3/CMIP5 models were not considered in this analysis, as very few LGM simulations are currently available from these models. We propose that these models will provide a useful validation of the correlation presented here

The dynamics of dwarf spheroidal galaxies

Digitisation of this thesis was sponsored by Arcadia Fund, a charitable fund of Lisbet Rausing and Peter Baldwin

A combined microfinance and training intervention can reduce HIV risk behaviour in young female participants.

OBJECTIVE: To assess effects of a combined microfinance and training intervention on HIV risk behavior among young female participants in rural South Africa. DESIGN: : Secondary analysis of quantitative and qualitative data from a cluster randomized trial, the Intervention with Microfinance for AIDS and Gender Equity study. METHODS: Eight villages were pair-matched and randomly allocated to receive the intervention. At baseline and after 2 years, HIV risk behavior was assessed among female participants aged 14-35 years. Their responses were compared with women of the same age and poverty group from control villages. Intervention effects were calculated using adjusted risk ratios employing village level summaries. Qualitative data collected during the study explored participants' responses to the intervention including HIV risk behavior. RESULTS: After 2 years of follow-up, when compared with controls, young participants had higher levels of HIV-related communication (adjusted risk ratio 1.46, 95% confidence interval 1.01-2.12), were more likely to have accessed voluntary counseling and testing (adjusted risk ratio 1.64, 95% confidence interval 1.06-2.56), and less likely to have had unprotected sex at last intercourse with a nonspousal partner (adjusted risk ratio 0.76, 95% confidence interval 0.60-0.96). Qualitative data suggest a greater acceptance of intrahousehold communication about HIV and sexuality. Although women noted challenges associated with acceptance of condoms by men, increased confidence and skills associated with participation in the intervention supported their introduction in sexual relationships. CONCLUSIONS: In addition to impacts on economic well being, women's empowerment and intimate partner violence, interventions addressing the economic and social vulnerability of women may contribute to reductions in HIV risk behavior

Voice and Agency: Empowering women and girls for shared prosperity

This document presents Voice and Agency: Empowering women and girls for shared prosperity is a major new report by the World Bank that shines a spotlight on the value of voice and agency, the patterns of constraints that limit their realization, and the associated costs, not only to individual women but to their families, communities, and societies. It highlights promising policies and interventions, and it identifies priority areas where further research and more and better data and evidence are needed. Underlining that agency has both intrinsic and instrumental, concrete value, this report puts advancing women's voice and agency squarely on the international development agenda

Does increased provider effort improve quality of care? Evidence from a standardised patient study on correct and unnecessary treatment

BACKGROUND: Poor quality of care, including overprovision (unnecessary care) is a global health concern. Greater provider effort has been shown to increase the likelihood of correct treatment, but its relationship with overprovision is less clear. Providers who make more effort may give more treatment overall, both correct and unnecessary, or may have lower rates of overprovision; we test which is true in the Tanzanian private health sector. METHODS: Standardised patients visited 227 private-for-profit and faith-based facilities in Tanzania, presenting with symptoms of asthma and TB. They recorded history questions asked and physical examinations carried out by the provider, as well as laboratory tests ordered, treatments prescribed, and fees paid. A measure of provider effort was constructed on the basis of a checklist of recommended history taking questions and physical exams. RESULTS: 15% of SPs received the correct care for their condition and 74% received unnecessary care. Increased provider effort was associated with increased likelihood of correct care, and decreased likelihood of giving unnecessary care. Providers who made more effort charged higher fees, through the mechanism of higher consultation fees, rather than increased fees for lab tests and drugs. CONCLUSION: Providers who made more effort were more likely to treat patients correctly. A novel finding of this study is that they were also less likely to provide unnecessary care, suggesting it is not simply a case of some providers doing "more of everything", but that those who do more in the consultation give more targeted care

Reliability and importance of structural diversity of climate model ensembles

PublishedJournal ArticleWe investigate the performance of the newest generation multi-model ensemble (MME) from the Coupled Model Intercomparison Project (CMIP5). We compare the ensemble to the previous generation models (CMIP3) as well as several single model ensembles (SMEs), which are constructed by varying components of single models. These SMEs range from ensembles where parameter uncertainties are sampled (perturbed physics ensembles) through to an ensemble where a number of the physical schemes are switched (multi-physics ensemble). We focus on assessing reliability against present-day climatology with rank histograms, but also investigate the effective degrees of freedom (EDoF) of the fields of variables which makes the statistical test of reliability more rigorous, and consider the distances between the observation and ensemble members. We find that the features of the CMIP5 rank histograms, of general reliability on broad scales, are consistent with those of CMIP3, suggesting a similar level of performance for present-day climatology. The spread of MMEs tends towards being "over-dispersed" rather than "under-dispersed". In general, the SMEs examined tend towards insufficient dispersion and the rank histogram analysis identifies them as being statistically distinguishable from many of the observations. The EDoFs of the MMEs are generally greater than those of SMEs, suggesting that structural changes lead to a characteristically richer range of model behaviours than is obtained with parametric/physical-scheme-switching ensembles. For distance measures, the observations and models ensemble members are similarly spaced from each other for MMEs, whereas for the SMEs, the observations are generally well outside the ensemble. We suggest that multi-model ensembles should represent an important component of uncertainty analysis. © 2013 The Author(s).We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP. For CMIP the US Department of Energy’s Pro- gram for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. M.C. was partially supported by funding from NERC grants NE/I006524/1 and NE/I022841/1. MW is supported by the Joint DECC/Defra Met Office Hadley Centre Climate Programme (GA01101). T.Y., J.D.A, H.S., S.E., M.Y., J.C.H. were supported by the Global Environment Research Fund of the Ministry of the Environment of Japan (S-10, Integrated Climate Assessment – Risks,Uncertainties and Society, ICA-RUS)

A Bayesian framework for emergent constraints: case studies of climate sensitivity with PMIP

In this paper we introduce a Bayesian framework, which is explicit about prior assumptions, for using model ensembles and observations together to constrain future climate change. The emergent constraint approach has seen broad application in recent years, including studies constraining the equilibrium climate sensitivity (ECS) using the Last Glacial Maximum (LGM) and the mid-Pliocene Warm Period (mPWP). Most of these studies were based on ordinary least squares (OLS) fits between a variable of the climate state, such as tropical temperature, and climate sensitivity. Using our Bayesian method, and considering the LGM and mPWP separately, we obtain values of ECS of 2.7 K (0.6–5.2, 5th–95th percentiles) using the PMIP2, PMIP3, and PMIP4 datasets for the LGM and 2.3 K (0.5–4.4) with the PlioMIP1 and PlioMIP2 datasets for the mPWP. Restricting the ensembles to include only the most recent version of each model, we obtain 2.7 K (0.7–5.2) using the LGM and 2.3 K (0.4–4.5) using the mPWP. An advantage of the Bayesian framework is that it is possible to combine the two periods assuming they are independent, whereby we obtain a tighter constraint of 2.5 K (0.8–4.0) using the restricted ensemble. We have explored the sensitivity to our assumptions in the method, including considering structural uncertainty, and in the choice of models, and this leads to 95 % probability of climate sensitivity mostly below 5 K and only exceeding 6 K in a single and most uncertain case assuming a large structural uncertainty. The approach is compared with other approaches based on OLS, a Kalman filter method, and an alternative Bayesian method. An interesting implication of this work is that OLS-based emergent constraints on ECS generate tighter uncertainty estimates, in particular at the lower end, an artefact due to a flatter regression line in the case of lack of correlation. Although some fundamental challenges related to the use of emergent constraints remain, this paper provides a step towards a better foundation for their potential use in future probabilistic estimations of climate sensitivity

Effectiveness and limitations of parameter tuning in reducing biases of top-of-atmosphere radiation and clouds in MIROC version 5

This study discusses how much of the biases in top-of-atmosphere (TOA) radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model Inter-comparison Project phase 5 (CMIP5) generation. We used output of a perturbed parameter ensemble (PPE) experiment conducted with an atmosphere–ocean general circulation model (AOGCM) without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5) was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude–longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds

Assessing household wealth in health studies in developing countries: a comparison of participatory wealth ranking and survey techniques from rural South Africa

BACKGROUND: Accurate tools for assessing household wealth are essential for many health studies in developing countries. Household survey and participatory wealth ranking (PWR) are two approaches to generate data for this purpose. METHODS: A household survey and PWR were conducted among eight villages in rural South Africa. We developed three indicators of household wealth using the data. One indicator used PWR data only, one used principal components analysis to combine data from the survey, while the final indicator used survey data combined in a manner informed by the PWR. We assessed internal consistency of the indices and assessed their level of agreement in ranking household wealth. RESULTS: Food security, asset ownership, housing quality and employment were important indicators of household wealth. PWR, consisting of three independent rankings of 9671 households, showed a high level of internal consistency (intraclass correlation coefficient 0.81, 95% CI 0.79-0.82). Data on 1429 households were available from all three techniques. There was moderate agreement in ranking households into wealth tertiles between the two indicators based on survey data (spearman rho = 0.69, kappa = 0.43), but only limited agreement between these techniques and the PWR data (spearman rho = 0.38 and 0.31, kappa = 0.20 and 0.17). CONCLUSION: Both PWR and household survey can provide a rapid assessment of household wealth. Each technique had strengths and weaknesses. Reasons for differences might include data inaccuracies or limitations in the methods by which information was weighted. Alternatively, the techniques may measure different things. More research is needed to increase the validity of measures of socioeconomic position used in health studies in developing countries

Les enseignants: à la recherche de leur profession

Les Enseignants: à la recherche de leur profession reprend les idées centrales présentées à la Conférence donnée, sur l'invitation de l'ATEE, au Séminaire de Barcelone, en 1993. Cet article est la reproduction du texte de support à la Conférence. Étant donné l'espace disponible, il n'a pas été possible de le travailler dans le sens d'une plus grande problématisation et élaboration théorique