Ambitious deep energy retrofits of buildings to accelerate the 1.5°C energy transition in Canada

Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits.     

Limits to climate action - Narratives of bioenergy with carbon capture and storage

In recent years, bio-energy with carbon capture and storage (BECCS) has been awarded a key role in climate mitigation scenarios explored by integrated assessment models and referenced in reports by the Intergovernmental Panel on Climate Change. Because a majority of scenarios limiting global warming to 2 °C or 1,5 °C include vast deployment of BECCS, a critical discussion has emerged among experts about the moral implications of thus introducing an unproven technology into the policy realm.In this paper, we analyse this discussion as it has played out between 2013 and 2019, with a focus on how expert narratives are constructed in the mass media about the possibilities for decarbonisation within the current political-economic order. We find there are almost no narratives that support massive deployment of BECCS, and that all narratives presuppose limits to decarbonisation imposed by the current political-economic system. The perception of such limits lead some to argue, through deterministic and apolitical narratives, for the necessity of negative emissions technologies, while others argue instead that “degrowth” is the only solution. Thus, there is a distinct lack of positive narratives about how capitalism can bring about decarbonisation.     

Beauty,Bath and Beyond: Framing Bathsheba as a Royal Fantasy in 2 Sam 11,1-5

This paper investigates the function of beauty in David and Bathsheba’s encounter in 2 Sam 11,1-5. It argues that the female bather’s pleasant appearance, rather than simply kindling king David’s desire, focalizes the woman as sexually available (and vulnerable) and wraps the whole episode in a royal fantasy of shared intimacy. The focus on Bathsheba’s beautiful body—her wash, her motion towards the king, her self-sanctification and her pregnancy—frames the episode in a very erotic way, suggesting adultery. It conceals the sexual violence committed by the king who sends, takes and sleeps with the woman. David’s violent entitlement to Bathsheba reveals the beauty politics at play in his royal House.     

Breadfruit Fermentation in Pohnpei,Micronesia: Site Formation,Archaeological Visibility,and Interpretive Strategies

Fermentation is a common method of processing and preserving breadfruit throughout the Pacific Islands. While these pits are often reported in the archaeological record, they can pose some interpretive challenges. This paper presents an analysis of probable archaeological breadfruit (Artocarpus altilis (Parkinson) Fosberg) fermentation pits on Temwen Island, Pohnpei, Micronesia. Using the existing ethnographic record as a guide, I present archaeological and paleoethnobotanical criteria for identifying fermentation features. Architectural and stratigraphic analyses from four excavated pits match ethnographic expectations. Phytolith analysis shows some concurrence in terms of taxonomic data, but is more useful for indicating disturbance specific to building activities. Based on the distribution and size of pits present in the survey area, I suggest that breadfruit fermentation took place as primarily a household level (rather than community level) activity during the late prehistoric and early historic period in Pohnpei.     

Experimental investigation of carbon dioxide trapping due to capillary retention in saline aquifers

Capillary trapping is a physical mechanism by which carbon dioxide (CO₂) is naturally immobilized in the pore spaces of aquifer rocks during geologic carbon sequestration operations, and thus a key aspect of estimating geologic storage potential. Here, we studied capillary trapping of supercritical carbon dioxide (scCO₂), and the effect of initial scCO₂ saturation and flow rate on the storage/trapping potential of Berea sandstone. We performed two‐phase, scCO₂‐brine displacements in two samples, each subject to four sequential drainage–imbibition core‐flooding cycles to quantify end‐point saturations of scCO₂ with the aid of micro‐ and macro‐computed tomography imaging. From these experiments, we found that between 51% and 75% of the initial CO₂ injected can be left behind after the brine injection. We also observed that the initial scCO₂ saturation influenced the residual scCO₂ saturation to a greater extent than the rate of brine injection under the experimental conditions examined. In spite of differences in the experimental conditions tested, as well as those reported in the literature, initial and residual saturations were found to follow a consistent relationship.     

The Neolithic refrigerator on a Friday night: How many people are coming to dinner and just what should I do with the slimy veggies in the back of the fridge?

Abstract

The prehistoric development of food storage represents a major evolutionary transition, one potentially more important than the initial domestication of plants. Researchers, however, have yet to really deal with some of the critical practical questions related to the materiality of food storage and decision-making. Drawing upon experimental research this paper seeks to identify and model some of the critical interconnections between anticipated food loss due to spoilage, storage decision-making and the need for people to store food for multiple years. Building on this foundation, and echoing ethnographic, ethnoarchaeological and archaeological research, this study argues that the concept of storage and surplus is underdeveloped and that in many cases the storage practices of prehistoric sedentary people do not reflect a food surplus so much as normal storage. Turning to a case study of changing Near Eastern Neolithic grain storage practices, this research argues that from the Natufian through Neolithic periods people increasingly relied upon cultivated domesticated plants and food storage. This required people to expand their use of pre-existing technology, such as plaster for lining storage features, to store sufficient amounts of food to overcome seasonal shortages, potential crop failures and minimise food spoilage due to a range of biological agents. Tracking shifts through time, the results of this study suggest that it is only with increased scale of food storage in the later stages of the Neolithic that we may see a materialization of a food surplus.     

Low‐temperature catalytic CO2 hydrogenation with geological quantities of ruthenium: a possible abiotic CH4 source in chromitite‐rich serpentinized rocks

Metal‐catalysed CO₂ hydrogenation is considered a source of methane in serpentinized (hydrated) igneous rocks and a fundamental abiotic process germane to the origin of life. Iron, nickel, chromium and cobalt are the catalysts typically employed in hydrothermal simulation experiments to obtain methane at temperatures >200°C. However, land‐based present‐day serpentinization and abiotic gas apparently develop below 100°C, down to approximately 40–50°C. Here, we document considerable methane production in thirteen CO₂ hydrogenation experiments performed in a closed dry system, from 20 to 90°C and atmospheric pressure, over 0.9–122 days, using concentrations of non‐pretreated ruthenium equivalent to those occurring in chromitites in ophiolites or igneous complexes (from 0.4 to 76 mg of Ru, equivalent to the amount occurring approximately in 0.4–760 kg of chromitite). Methane production increased with time and temperature, reaching approximately 87 mg CH₄ per gram of Ru after 30 days (2.9 mgCH₄/g_ru/day) at 90°C. At room temperature, CH₄ production rate was approximately three orders of magnitude lower (0.003 mgCH₄/g_ru/day). We report the first stable carbon and hydrogen isotope ratios of abiotic CH₄ generated below 100°C. Using initial δ¹³C_CO2 of ‐40‰, we obtained room temperature δ¹³C_CH4 values as ¹³C depleted as ?142‰. With time and temperature, the C‐isotope separation between CO₂ and CH₄ decreased significantly and the final δ¹³C_CH4 values approached that of initial δ¹³C_CO2. The presence of minor amounts of C₂‐C₆ hydrocarbons is consistent with observations in natural settings. Comparative experiments at the same temperatures with iron and nichel catalysts did not generate CH₄. Ru‐enriched chromitites could potentially generate methane at low temperatures on Earth and on other planets.     

Surface controls on the characteristics of natural CO2 seeps: implications for engineered CO2 stores

CO₂ injected into rock formations for deep geological storage must not leak to surface, since this would be economically and environmentally unfavourable, and could present a human health hazard. In Italy natural CO₂ degassing to the surface via seeps is widespread, providing an insight into the various styles of subsurface ‘plumbing’ as well as surface expression of CO₂ fluids. Here we investigate surface controls on the distribution of CO₂ seep characteristics (type, flux and temperature) using a large geographical and historical data set. When the locations of documented seeps are compared to a synthetic statistically random data set, we find that the nature of the CO₂ seeps is most strongly governed by the flow properties of the outcropping rocks, and local topography. Where low‐permeability rocks outcrop, numerous dry seeps occur and have a range of fluxes. Aqueous fluid flow will be limited in these low‐permeability rocks, and so relative permeability effects may enable preferential CO₂ flow. CO₂ vents typically occur along faults in rocks that are located above the water table or are low permeability. Diffuse seeps develop where CO₂ (laterally supplied by these faults) emerges from the vadose zone and where CO₂ degassing from groundwater follows a different flow path due to flow differences for water and CO₂ gas. Bubbling water seeps (characterized by water bubbling with CO₂) arise where CO₂ supply enters the phreatic zone or an aquifer. CO₂‐rich springs often emerge where valleys erode into CO₂ aquifers, and these are typically high flux seeps. Seep type is known to influence human health risk at CO₂ seeps in Italy, as well as the topography surrounding the seep which affects the rate of gas dispersion by wind. Identifying the physical controls on potential seep locations and seep type above engineered CO₂ storage operations is therefore crucial to targeted site monitoring strategy and risk assessment. The surface geology and topography above a CO₂ store must therefore be characterized in order to design the most effective monitoring strategy.     

Food for all: An agent-based model to explore the emergence and implications of cooperation for food storage

Abstract

A consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution.     

Salafī‐Ashʻarī Polemics of the 3rd & 4th Islamic Centuries

While Sunnism is the largest sect of Islam, Sunnism itself is divided into many strands. The two main strands of Sunnism for the last few centuries are the Atharī (or Salafī) strand, and the Ash?arī strand. This papers seeks to examine the earliest recorded controversies that signal this intra‐Sunnī divide. While each of these two groups has historically attempted to claim true Sunnī ‘orthodoxy’ by denying the legitimacy, and at times even the early existence, of the other, it will be shown that the genesis of this intra‐Sunnī divide dates back to the first century of Sunnism itself, viz., the 3^rd AH/8^th CE centuries, and that there are specific historic incidents that indicate theological tensions within the nascent Sunnī movement that would later be manifested in the two streams of Ash?arism and Salafism. Hence, it can be argued that Sunnism was never truly unified to begin with, and that these incidents demonstrate theological tensions that existed from its very origins.