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Background Over the last 5 years (2013-2017), the Caribbean region has faced an unprecedented crisis of co-occurring epidemics of febrile illness due to arboviruses transmitted by the Aedes sp. mosquito (dengue, chikungunya, and Zika). Since 2013, the Caribbean island of Barbados has experienced 3 dengue outbreaks, 1 chikungunya outbreak, and 1 Zika fever outbreak. Prior studies have demonstrated that climate variability influences arbovirus transmission and vector population dynamics in the region, indicating the potential to develop public health interventions using climate information. The aim of this study is to quantify the nonlinear and delayed effects of climate indicators, such as drought and extreme rainfall, on dengue risk in Barbados from 1999 to 2016. Methods and findings Distributed lag nonlinear models (DLNMs) coupled with a hierarchal mixed-model framework were used to understand the exposure-lag-response association between dengue relative risk and key climate indicators, including the standardised precipitation index (SPI) and minimum temperature (Tmin). The model parameters were estimated in a Bayesian framework to produce probabilistic predictions of exceeding an island-specific outbreak threshold. The ability of the model to successfully detect outbreaks was assessed and compared to a baseline model, representative of standard dengue surveillance practice. Drought conditions were found to positively influence dengue relative risk at long lead times of up to 5 months, while excess rainfall increased the risk at shorter lead times between 1 and 2 months. The SPI averaged over a 6-month period (SPI-6), designed to monitor drought and extreme rainfall, better explained variations in dengue risk than monthly precipitation data measured in millimetres. Tmin was found to be a better predictor than mean and maximum temperature. Furthermore, including bidimensional exposure-lag-response functions of these indicators-rather than linear effects for individual lags-more appropriately described the climate-disease associations than traditional modelling approaches. In prediction mode, the model was successfully able to distinguish outbreaks from nonoutbreaks for most years, with an overall proportion of correct predictions (hits and correct rejections) of 86% (81%:91%) compared with 64% (58%:71%) for the baseline model. The ability of the model to predict dengue outbreaks in recent years was complicated by the lack of data on the emergence of new arboviruses, including chikungunya and Zika. Conclusion We present a modelling approach to infer the risk of dengue outbreaks given the cumulative effect of climate variations in the months leading up to an outbreak. By combining the dengue prediction model with climate indicators, which are routinely monitored and forecasted by the Regional Climate Centre (RCC) at the Caribbean Institute for Meteorology and Hydrology (CIMH), probabilistic dengue outlooks could be included in the Caribbean Health-Climatic Bulletin, issued on a quarterly basis to provide climate-smart decision-making guidance for Caribbean health practitioners. This flexible modelling approach could be extended to model the risk of dengue and other arboviruses in the Caribbean region., Author(s): Rachel Lowe 1,2,3,*, Antonio Gasparrini 4,5, Cédric J. Van Meerbeeck 6, Catherine A. Lippi 7, Roché Mahon 6, Adrian R. Trotman 6, Leslie Rollock 8, Avery Q. J. Hinds [...]

Objective: Climatic conditions may enable or deter active school transportation in many North American cities, but the topic remains largely overlooked in the existing literature. This study explores the effect of seasonal climate (i.e., fall versus winter) and weekly weather conditions (i.e., temperature, precipitation) on active travelling to school across different built and policy environments. Methods: Home-to-school trips by 11-12-year-old children in the City of Toronto were examined using data from the 2006 Transportation Tomorrow Survey. Binomial logistic regressions were estimated to explore the correlates of the choice of active (i.e., walking) versus non-active (i.e., private automobile, transit and school bus) mode for school trips. Results: Climate and weather-related variables were not associated with choice of school travel mode. Children living within the sidewalk snow-plough zone (i.e., in the inner-suburban neighbourhoods) were less likely to walk to school than children living outside of the zone (i.e., in the inner-city neighbourhoods). Conclusion: Given that seasonality and short-term weather conditions appear not to limit active school transportation in general, built environment interventions designed to facilitate active travel could have benefits that spill over across the entire year rather than being limited to a particular season. Educational campaigns with strategies for making the trip fun and ensuring that the appropriate clothing choices are made are also warranted in complementing built environment modifications. Key words: Climate; weather; school travel; walking; built environment Objectif : Les conditions climatiques pourraient favoriser ou entraver le transport scolaire actif dans de nombreuses villes d'Amerique du Nord, mais ce sujet est en grande partie inexplore dans la recherche existante. Notre etude porte sur l'effet du climat saisonnier (p. ex., automnal ou hivernal) et des conditions atmospheriques hebdomadaires (temperature, precipitations) sur le transport scolaire actif dans differents milieux batis et environnements politiques. Methode : Nous avons examine les trajets de la maison a l'ecole d'enfants de 11 et 12 ans vivant a Toronto a l'aide des donnees du Sondage pour le systeme de transports de demain de 2006. Des regressions logistiques binomiales ont ete estimees pour explorer les correlats du choix d'un mode de transport actif (comme la marche) ou non actif (voiture privee, transports en commun, autobus scolaire) pour se rendre a l'ecole. Resultats : Les variables liees au climat et a la meteo n'etaient pas associees au choix du mode de transport scolaire. Les enfants vivant a l'interieur de la zone de deneigement des trottoirs (c.-a-d. dans les quartiers de la proche banlieue) etaient moins susceptibles de se rendre a l'ecole en marchant que les enfants vivant hors de cette zone (c.-a-d. dans les quartiers du centre-ville). Conclusion : Etant donne que les cycles saisonniers et les conditions atmospheriques de courte duree ne semblent pas limiter le transport scolaire actif en general, les interventions sur le milieu bati concues pour faciliter les deplacements actifs pourraient avoir des repercussions positives toute l'annee plutot que de se limiter a une saison particuliere. On devrait aussi envisager, pour completer des modifications au milieu bati, des campagnes de sensibilisation comportant des strategies pour rendre le trajet amusant et pour aider les enfants a choisir des vetements appropries. Mots cles : climat; temps; transport scolaire; marche; milieu bati, Children who walk or cycle for school transportation tend to be more physically active overall than those who use other travel modes. (1) Policy and program initiatives in North America [...]

We present a new dynamic dominant height growth model based on Cieszewski's generalized algebraic difference approach (GADA) advanced dynamic site equation strengthened by the use of explicit climate and soil variables (i.e., H = f([H.sub.0],[T.sub.0], T site conditions)). The results suggest that the inclusion of climatic variables would improve the applicability of the inter-regional model in regions in which climate and soil type lead to intea-regional variability. The new model reduces the bias present in a previous dynamic model that did not include climatic attributes and improves the model efficiency across the different age classes. Climate has a multiplicative effect on dominant tree growth in the early development stages ( Nous presentons ici un nouveau modele dynamique de croissance en hauteur dominante fonde sur l'equation de la methode de la difference algebrique generalise (GADA) de l'indice de qualite de station de Cieszewski renforcee par l'utilisation des variables explicites du climat et du sol, c.-a-d. H = f([H.sub.0], [T.sub.0], T, tat du site). Les resultats indiquent que l'inclusion des variables climatiques permettrait d'ameliorer l'applicabilite du modele interrgional dans les regions ou le climat et le type de sol sont a l'origine de la variabilite intrargionale. Le nouveau modele permet de rduire le biais present dans un modele dynamique precedent qui n'incluait pas les caracteristiques climatiques et ameliore l'efficacite de ce modele pour l'ensemble des classes d'age. Le climat exerce un effet multiplicateur sur la croissance des arbres dominants durant les premiers stades de developpement ( [Traduit par la Redaction], Introduction Mediterranean maritime pine (MMP; Pinus pinaster Ait.) is widely distributed in the Mediterranean basin, occupying approximately 4 x [10.sup.6] ha (Ribeiro et al. 2001). The species grows in a [...]

Kislev et al.'s (2006a) recent claims of fig cultivation and domestication dated to the second half of the twelfth millennium BP in the Lower Jordan valley are sensational. For some, [...]

ABSTRACT. We recorded an unusually warm period in early April 1979 along the coastline at the end of the Hall Peninsula on southeastern Baffin Island, Nunavut. Maximum temperatures remained at [...]