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As the effects of global climate change become more apparent, animal species will become increasingly affected by extreme climate and its effect on the environment. There is a pressing need to understand animal physiological and behavioural responses to climatic stressors. We used the reactive scope model as a framework to investigate the influence of drought conditions on vervet monkey ( Chlorocebus pygerythrus ) behaviour, physiological stress and survival across 2.5 years in South Africa. Data were collected on climatic, environmental and behavioural variables and physiological stress via faecal glucocorticoid metabolites (fGCMs). There was a meaningful interaction between water availability and resource abundance: when food availability was high but standing water was unavailable, fGCM concentrations were higher compared to when food was abundant and water was available. Vervet monkeys adapted their behaviour during a drought period by spending a greater proportion of time resting at the expense of feeding, moving and social behaviour. As food availability decreased, vervet mortality increased. Peak mortality occurred when food availability was at its lowest and there was no standing water. A survival analysis revealed that higher fGCM concentrations were associated with an increased probability of mortality. Our results suggest that with continued climate change, the increasing prevalence of drought will negatively affect vervet abundance and distribution in our population. Our study contributes to knowledge of the limits and scope of behavioural and physiological plasticity among vervet monkeys in the face of rapid environmental change.

Post-processing has received much attention during the last couple of years within the hydrological community, and many different methods have been developed and tested, especially in the field of flood forecasting. Apart from the different meanings of the phrase “post-processing” in meteorology and hydrology, in this paper, it is regarded as a method to correct model outputs (predictions) based on meteorological (1) observed input data, (2) deterministic forecasts (single time series) and (3) ensemble forecasts (multiple time series) and to derive predictive uncertainties. So far, the majority of the research has been related to floods, how to remove bias and improve the forecast accuracy and how to minimize dispersion errors. Given that global changes are driving climatic forces, there is an urgent need to improve the quality of low-flow predictions, as well, even in regions that are normally less prone to drought. For several catchments in Switzerland, different post-processing methods were tested with respect to low stream flow and flooding conditions. The complexity of the applied procedures ranged from simple AR processes to more complex methodologies combining wavelet transformations and Quantile Regression Neural Networks (QRNN) and included the derivation of predictive uncertainties. Furthermore, various verification methods were tested in order to quantify the possible improvements that could be gained by applying these post-processing procedures based on different stream flow conditions. Preliminary results indicate that there is no single best method, but with an increase of complexity, a significant improvement of the quality of the predictions can be achieved.

An aerosol reactor was tested for the thermal reduction of ceria as part of a solar thermochemical redox cycle for producing H2 and CO from H2O and CO2. The design is based on the downward aerosol flow of ceria particles, counter to an argon sweep gas, which are rapidly heated and thermally reduced within residence times of less than 1 s. When operating in the temperature range of 1723–1873 K and at oxygen partial pressures between 5 × 10–5 and 1.2 × 10–4 atm, reduction extents of small particles (Dv50 = 12 μm) approached those predicted by thermodynamics. However, heat- and mass-transfer effects were found to limit their conversion when the ceria mass flow rate was increased above 100 mg s–1. This reactor concept inherently results in separation of the reduced ceria and evolved O2(g), operates isothermally throughout the day, and decouples the reduction and oxidation steps in both space and time for potential 24-h syngas generation.

Optimization models can support decision-makers in the synthesis and operation of multi-sector energy systems. To identify the optimal design and operation of a low-carbon system, we need to consider high temporal and spatial variability in the electricity supply, sector coupling, and environmental impacts over the whole life cycle. Incorporating such aspects in optimization models is demanding. To avoid redundant research efforts and enhance transparency, the developed models and used data sets should be shared openly. In this work, we present the SecMOD framework for multi-sector energy system optimization incorporating life-cycle assessment (LCA). The framework allows optimizing multiple sectors jointly, ranging from industrial production and their linked energy supply systems to sector-coupled national energy systems. The framework incorporates LCA to account for environmental impacts. We hence provide the first open-source framework to consistently include a holistic life-cycle perspective in multi-sector optimization by a full integration of LCA. We apply the framework to a case-study of the German sector-coupled energy system. Starting with few base technologies, we demonstrate the modular capabilities of SecMOD by the stepwise addition of technologies, sectors and existing infrastructure. Our modular open-source framework SecMOD aims to accelerate research for sustainable energy systems by combining multi-sector energy system optimization and life-cycle assessment.

This paper discusses the influence of time horizon on dynamic optimization of small-size wastewater treatment plants alternating aerobic and anoxic processes. The optimization problem consists in determining the aeration policy (air-on and air-off periods) that minimizes the energy dissipated by the aeration system subject to both effluent and operating constraints. Optimization over short time horizons is first considered and reductions of the energy consumption up to 30% are obtained with respect to the usual operating mode of the process. But the application of such aeration strategies eventually results in a biomass wash-out when applied over long time periods. Here, it is shown that long time horizon optimized policies guarantee a durable functioning of the treatment plant. The resulting energy consumption savings are however lower (up to 15%), but are still important.

Carbon capture and storage (CCS) may play a significant role in reducing greenhouse gas emissions. Noble gases are potential tracers to monitor subsurface CO2 storage sites and verify their containment. Naturally occurring noble gases have been used successfully to refute alleged CO2 leakage in the past. We present results from several sampling campaigns at two Norwegian CO2 capture facilities, the demonstration plant Technology Centre Mongstad (TCM) and the natural gas processing plant with CO2 capture and storage on Melkøya. The gas streams in the capture plants were monitored with a combination of on-site mass spectrometry and subsequently analysed discrete samples. This allows us to define the factors controlling noble gas concentrations in captured CO2, to monitor temporal variation of noble gas concentrations and finally evaluate the potential to use noble gases as inherent environmental tracers for labelling CO2 in storage reservoirs. At both sites, CO2 is captured using amine gas treatment. Noble gas concentrations in the gas streams were observed to decrease by several orders of magnitude during the processing. Isotopic ratios are air-like for CO2 captured after natural gas combustion at TCM and natural gas-like for CO2 captured from natural gas processing on Melkøya. Further, we detected a solubility trend caused by the amine solvent at TCM with higher solubility for heavier noble gases. We find that the relative concentrations of noble gases in the captured CO2 are defined by the gas from which the CO2 is captured and the design of the amine gas treatment process. Both factors were observed to cause temporal variation in the captured CO2. Using mixing and noble gas partitioning calculations we show that the significant depletion in noble gas concentrations, together with degassing of noble gas enriched formation water, means that the injected CO2 will inherit the noble gas signature of the storage formation, even following the injection of significant CO2 volumes. Any CO2 leaked from the storage formation is thus likely to have a crustal noble gas signature, characteristic of the storage site, which can be targeted for monitoring. © 2020 The Author(s) International Journal of Greenhouse Gas Control, 106 ISSN:1750-5836 ISSN:1878-0148

Abstract The buildings and construction sector is responsible for nearly 40% of the total greenhouse emissions (GHG). Considering 50% of the building stock that will exist in 2050 is yet to be built and most of it will be devoted to housing; the sector is a determinant and transformative force to strengthen sustainability, reducing CO2 emissions and environmental degradation worldwide. Most of the increase in construction and housing is set to occur in developing countries and mainly in cities in Asia and Africa. This global picture places new housing programs in the rapidly urbanising regions as potential agents of sustainable transformation, with positive outcomes for both communities and the environment. Investing in sustainable housing has significant and real value in reducing emissions, confronting climate change, and generating better planned, inclusive, and sustainable cities. The holistic benefit achieved with the implementation of carbon neutral and carbon negative technologies is often scattered, and an integrated view of it would be a key tool to support the development of sustainable housing programmes. Considering that technologies to decarbonize and render the construction sector more sustainable have already been developed, there is a need to contrast their applicability to different countries and contexts in order to verify their functionality and identify gaps for improvement. The recent decade has witnessed a significant improvement at the global level with regards to the application of the concept of sustainability to the built environment, this being demonstrated by the multiple sustainability ratings and frameworks being developed to certify building performance. Their adoption has been critically important in most regions in the so-called Global North, where countries have started enforcing them at a normative level. While these tools’ accuracy and comprehensiveness could be disputed, their importance in promoting a systematic standardisation of the adoption of sustainability measures in the built environment is endorsed. Nevertheless, the diffusion of such tools and frameworks across rapidly urbanising middle and low-income countries has been so far extremely limited. There are myriad reasons why this is the case: tools based for high-income country contexts, their complexity, the need for accurate data and specific capacity for their adoption and diffusion, the lack of contextual relevance with regards to the specific market, culture and behavioural dynamics, and more. The following paper aims at demonstrating the value of shifting toward sustainable building practices by a comparative analysis of existing global tools and certifications and their applicability to low and middle-income countries undergoing a rapid urbanisation process. It proposes a three-phased multi-stakeholders methodology. The outcome of these three phases is combined, providing a more appropriate definition of effective and operative guidelines and tools for sustainable housing in rapidly urbanising middle and lowincome regions.