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• Sheltered natural carbonation can be similar between different climates. • Huge impact of curing on natural carbonation for very early age (i.e. 1 day) • Impact of curing is negligible for advanced curing age, regardless of cement type. • Strong impact of precipitation on natural carbonation. • The higher the number of rainy days, the lower the carbonation speed. This paper describes a unique international inter-laboratory study on the carbonation resistance of concrete prepared with different supplementary cementing materials. Concrete specimens – from 45 different concrete mixtures – prepared centrally in Lafarge Centre de Recherche (France) were shipped in a sealed condition to 4 other academia research laboratories (located in USA, Canada, India and China). The specimens were exposed to the ambient environments and atmospheric CO2 concentrations in the five locations, including Lafarge Centre de Recherche in France, in both sheltered and unsheltered condition for a period of 5 years. Measurements of carbonation depth were performed at periodic intervals, and the data was analyzed to assess the influence of climatic conditions on the resistance to carbonation. The results indicate that the general trend of carbonation is not much different irrespective of the macroclimate. Further, the number of rainy days seems to have a more significant influence on the progress of carbonation than the total rainfall in the region. [ABSTRACT FROM AUTHOR]

This paper contributes to the literature on Indigenous health, human dimensions of climate change, and place-based dimensions of health by examining the role of environment for Inuit health in the context of a changing climate. We investigated the relationship between one key element of the environment – sea ice – and diverse aspects of health in an Inuit community in northern Canada, drawing on population health and health geography approaches. We used a case study design and participatory and collaborative approach with the community of Nain in northern Labrador, Canada. Focus groups (n = 2), interviews (n = 22), and participant observation were conducted in 2010–11. We found that an appreciation of place was critical for understanding the full range of health influences of sea ice use for Inuit. Negative physical health impacts were reported on less frequently than positive health benefits of sea ice use, which were predominantly related to mental/emotional, spiritual, social, and cultural health. We found that sea ice means freedom for sea ice users, which we suggest influences individual and collective health through relationships between sea ice use, culture, knowledge, and autonomy. While sea ice users reported increases in negative physical health impacts such as injuries and stress related to changing environmental conditions, we suggest that less tangible climate change impacts related to losses of health benefits and disruptions to place meanings and place attachment may be even more significant. Our findings indicate that climate change is resulting in and compounding existing environmental dispossession for Inuit. They also demonstrate the necessity of considering place meanings, culture, and socio-historical context to assess the complexity of climate change impacts on Indigenous environmental health. [ABSTRACT FROM AUTHOR]

Abstract: Grass reference evapotranspiration (ETo) is an important agrometeorological parameter for climatological and hydrological studies, as well as for irrigation planning and management. There are several methods to estimate ETo, but their performance in different environments is diverse, since all of them have some empirical background. The FAO Penman–Monteith (FAO PM) method has been considered as a universal standard to estimate ETo for more than a decade. This method considers many parameters related to the evapotranspiration process; net radiation (Rn), air temperature (T), vapor pressure deficit (Δe), and wind speed (U); and has presented very good results when compared to data from lysimeters populated with short grass or alfalfa. In some conditions, the use of the FAO PM method is restricted by the lack of input variables. In these cases, when data are missing, the option is to calculate ETo by the FAO PM method using estimated input variables, as recommended by FAO Irrigation and Drainage Paper 56. Based on that, the objective of this study was to evaluate the performance of the FAO PM method to estimate ETo when Rn, Δe, and U data are missing, in Southern Ontario, Canada. Other alternative methods were also tested for the region: Priestley–Taylor, Hargreaves, and Thornthwaite. Data from 12 locations across Southern Ontario, Canada, were used to compare ETo estimated by the FAO PM method with a complete data set and with missing data. The alternative ETo equations were also tested and calibrated for each location. When relative humidity (RH) and U data were missing, the FAO PM method was still a very good option for estimating ETo for Southern Ontario, with RMSE smaller than 0.53mmday−1. For these cases, U data were replaced by the normal values for the region and Δe was estimated from temperature data. The Priestley–Taylor method was also a good option for estimating ETo when U and Δe data were missing, mainly when calibrated locally (RMSE =0.40mmday−1). When Rn was missing, the FAO PM method was not good enough for estimating ETo, with RMSE increasing to 0.79mmday−1. When only T data were available, adjusted Hargreaves and modified Thornthwaite methods were better options to estimate ETo than the FAO PM method, since RMSEs from these methods, respectively 0.79 and 0.83mmday−1, were significantly smaller than that obtained by FAO PM (RMSE =1.12mmday−1). [Copyright &y& Elsevier]

Abstract: When planning the acquisition of new palaeo proxy data for reconstructing past climates, many factors influence the decision of where the proxies are to be collected. One such influence is the likelihood of recording a significant climate change relative to the modern. Another consideration, which is less often considered, is the desire to target regions in which there is significant uncertainty in numerical model predictions of past climate change. New proxy data in these regions enables a more rigorous test of model simulations, and results in better constraints on the various boundary conditions used to force the models. In this paper we present a methodology for targeting new palaeo proxy data, based on model simulations. We use the terrestrial late Miocene (11.6 to 5.3 Ma) as a case study. The late Miocene climate provides insights into future climate behavior, as it is believed to have been considerably warmer than the modern. We carry out a suite of late Miocene atmosphere-only General Circulation Model simulations, which we initially evaluate relative to an example dataset of terrestrial temperature and precipitation. In terms of targeting future data acquisition, we locate those regions in the model which exhibit the largest change in temperature and/or precipitation relative to the pre-industrial. We also locate those regions which display the largest variability between the model simulations, because new data in these regions are most likely to provide a strict test of the reliability of the model results. Among other regions, the Amazon basin, the Chad basin, central Canada, and northern India are identified as potentially useful areas to collect data. [Copyright &y& Elsevier]