Search results for " Global warming"
showing 10 items of 85 documents
Greenhouse Gas Emissions from Membrane Bioreactors
2017
Nowadays, it is widely accepted that wastewater treatment plants (WWTPs) are significant sources of greenhouse gas (GHG) emission, contributing to the anthropogenic sources. Among the GHG emitted from WWTPs, nitrous oxide (N2O) has been identified of having the major interest/concern, since its high global warming potential (GWP), is 298 times higher than that of CO2 and also to its capability to react with stratospheric ozone causing the layer depletion. Up to now, most of the experimental investigations have been carried out on conventional activated sludge (CAS) processes. The knowledge of N2O emission from advanced technologies such membrane bioreactors (MBRs) is still very limited. The…
Quantifying sensitivity and uncertainty analysis of a new mathematical model for the evaluation of greenhouse gas emissions from membrane bioreactors
2015
Abstract A new mathematical model able to quantify greenhouse gas (GHG) emissions in terms of carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) for a Membrane Bioreactor (MBR) is presented. The proposed mathematical model is of the Activated Sludge Model (ASM) family and takes into account simultaneously both biological and physical processes (e.g., membrane fouling). An analysis of the key factors and sources of uncertainty influencing GHG emissions is also presented. Specifically, the standardized regression coefficient, the Extended-FAST and a Monte Carlo based method are employed for assessing model factors which influence three performance indicators: effluent quality index, operational…
Towards a conceptual mathematical tool linking physical and biological processes for a reduction of ghg emissions from an mb-mbr plant
2016
The current study explores the influence of the air flow rate on greenhouse gas (GHG) emissions (direct and indirect), the operational costs (OCs), the effluent quality index (EQI) and effluent fines (EF). An University Cape Town (UCT) moving bed (MB) membrane bioreactor (MBR) pilot plant has been considered as case study where the influence of the air flow rate on the biological and physical processes has been analyzed. Constitutive relationships between the air flow rate and some performance indicators (i.e., EQI, OCs, direct and indirect GHG emissions) have been identified. Results showed that the EQI increases at low flow rate likely due to the dissolved oxygen (DO) limitation in the bi…
An integrated building energy simulation early—Design tool for future heating and cooling demand assessment
2022
Climate change and its effects are becoming clear on a global scale either from the perspective of global warming and the increase in the rate of occurrence of weather events of extreme magnitude. This has impacts also for sure on the standard building performance analysis approach, since the buildings designed today are supposed to withstand for the following decades climate impacts that may be different than those they were designed for. The paper proposes a simple, easy to use and freely available building simulation utility which performs morphing of existing weather data files and, by connecting to the Energy Plus simulation routine, allows to perform future climate building simulation…
Life Cycle Assessment of solar heating and cooling systems: the tool “ELISA”
2018
Solar heating and cooling (SHC) systems play an important role in the achievement of energy and climate European goals. The benefits of these technologies should be evaluated taking into account their lifecycle energy and environmental impacts, calculated by applying the Life Cycle Assessment (LCA) methodology. The development of a complete LCA can be difficult and time-consuming particularly for no-LCA experts, discouraging them in the inclusion of the lifecycle perspective in their assessments. To overcome this limit, the paper presents “ELISA - Environmental Lifecycle Impacts of Solar Air-conditioning systems”, a user-friendly simplified tool for estimating the lifecycle energy and envir…
Analysis of the effects of climate change on the energy and environmental performance of a building with and without onsite generation from renewable…
2020
Climate Change is a priority, due to the large variety of implications and importance that it may cause in the next decades. In this context, the building sector is a significant contributor to greenhouse gas emissions. For this reason, buildings should be designed in such a way that they are responsible for fewer GHG emissions. In this context, the paper analyses the potential impact of climate change on the energy performances of buildings, with and without onsite generation from renewable energy, using a prototype building located in Messina (Italy) as case study. The analysis is based on Intergovernmental Panel on Climate Change RCP scenarios and the results confirm the already known ov…
Nano- to Global-Scale Uncertainties in Terrestrial Enhanced Weathering.
2022
Enhanced weathering (EW) is one of the most promising negative emissions technologies urgently needed to limit global warming to at least below 2 °C, a goal recently reaffirmed at the UN Global Climate Change conference (i.e., COP26). EW relies on the accelerated dissolution of crushed silicate rocks applied to soils and is considered a sustainable solution requiring limited technology. While EW has a high theoretical potential of sequestering CO2, research is still needed to provide accurate estimates of carbon (C) sequestration when applying different silicate materials across distinct climates and major soil types in combination with a variety of plants. Here we elaborate on fundamental …
A database for the monitoring of thermal anomalies over the Amazon forest and adjacent intertropical oceans
2015
AbstractAdvances in information technologies and accessibility to climate and satellite data in recent years have favored the development of web-based tools with user-friendly interfaces in order to facilitate the dissemination of geo/biophysical products. These products are useful for the analysis of the impact of global warming over different biomes. In particular, the study of the Amazon forest responses to drought have recently received attention by the scientific community due to the occurrence of two extreme droughts and sustained warming over the last decade. Thermal Amazoni@ is a web-based platform for the visualization and download of surface thermal anomalies products over the Ama…
Decreasing Phanerozoic extinction intensity as a consequence of Earth surface oxygenation and metazoan ecophysiology
2021
The decline in background extinction rates of marine animals through geologic time is an established but unexplained feature of the Phanerozoic fossil record. There is also growing consensus that the ocean and atmosphere did not become oxygenated to near-modern levels until the mid-Paleozoic, coinciding with the onset of generally lower extinction rates. Physiological theory provides us with a possible causal link between these two observations-predicting that the synergistic impacts of oxygen and temperature on aerobic respiration would have made marine animals more vulnerable to ocean warming events during periods of limited surface oxygenation. Here, we evaluate the hypothesis that chang…
Using natural analogues to investigate the effects of climate change and ocean acidification on Northern ecosystems
2018
AbstractNorthern oceans are in a state of rapid transition. Still, our knowledge of the likely effects of climate change and ocean acidification on key species in the food web, functionally important habitats and the structure of Arctic and sub-Arctic ecosystems is limited and based mainly on short-term laboratory studies on single species. This review discusses how tropical and temperate natural analogues of carbonate chemistry drivers, such as CO2 vents, have been used to further our knowledge of the sensitivity of biological systems to predicted climate change, and thus assess the capacity of different species to show long-term acclimation and adaptation to elevated levels of pCO2. Natur…