Projected climate change impacts upon dew yield in the Mediterranean basin

Water scarcity is increasingly raising the need for non-conventional water resources, particularly in arid and semi-arid regions. In this context, atmospheric moisture can potentially be harvested in the form of dew, which is commonly disregarded from the water budget, although its impact may be significant when compared to rainfall during the dry season. In this study, a dew atlas for the Mediterranean region is presented illustrating dew yields using the yield data collected for the 2013 dry season. The results indicate that cumulative monthly dew yield in the region can exceed 2.8mm at the end of the dry season and 1.5mm during the driest months, compared to <1mm of rainfall during the same period in some areas. Dew yields were compared with potential evapotranspiration (PET) and actual evapotranspiration (ET) during summer months thus highlighting the role of dew to many native plants in the region. Furthermore, forecasted trends in temperature and relative humidity were used to estimate dew yields under future climatic scenarios. The results showed a 27% decline in dew yield during the critical summer months at the end of the century (2080).

Operational and environmental determinants of in-vehicle CO and PM2.5 exposure

This study presents a modeling framework to quantify the complex roles that traffic, seasonality, vehicle characteristics, ventilation, meteorology, and ambient air quality play in dictating in-vehicle commuter exposure to CO and PM2.5. For this purpose, a comprehensive one-year monitoring program of 25 different variables was coupled with a multivariate regression analysis to develop models to predict in-vehicle CO and PM2.5 exposure using a database of 119 mobile tests and 120 fume leakage tests. The study aims to improve the understanding of in-cabin exposure, as well as interior-exterior pollutant exchange. Model results highlighted the strong correlation between out-vehicle and in-vehicle concentrations, with the effect of ventilation type only discerned for PM2.5 levels. Car type, road conditions, as well as meteorological conditions all played a significant role in modulating in-vehicle exposure. The CO and PM2.5 exposure models were able to explain 72 and 92% of the variability in measured concentrations, respectively. Both models exhibited robustness and no-evidence of over-fitting.