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Direct air capture of carbon dioxide (CO 2) is technically a feasible solution for reducing atmospheric CO 2 concentrations at scale, building on decades of global research. However, powering such systems even partially with CO 2 -intensive fossil fuels results in more CO 2 emissions. This paper presents a novel energy management strategy (EMS) to further explore modular offshore wind energy off Canada's West Coast via power-to-direct air capture and power-to-gas systems. The system architecture includes a 15 MW wind turbine paired with a hydrogen energy storage system, i.e. hydrogen production and storage, and direct air capture (DAC) units. Hydrogen production from wind generation is stored and used to offer two key benefits: to deliver the thermal loads of the DAC system, and to meet hydrogen demand for external consumers. The proposed EMS offers an extra degree of freedom to operate the designed system by setting the priority either to maximize the amount of CO 2 capture or to maximize the amount of H 2 production for external consumers. In particular, the study incorporates dynamic mathematical modeling and constraints formulation for the aforementioned scenarios; DAC priority for CO 2 capture and H 2 for external hydrogen demand satisfaction. The effectiveness of the proposed EMS is shown through extensive simulations with different seasonal conditions. • Detailed mathematical dynamical models for offshore power-to-DAC and power-to-gas systems. • Green hydrogen production for two-fold benefits; H 2 for meeting DAC thermal loads, and H 2 as fuel for external consumers. • Scenario 1 prioritize the CO 2 capture rate, while scenario 2 maximizes the H 2 production for external consumers. • Design of EMS shows the correct unit commitment of the CO 2 capture rate and H 2 tracking. [ABSTRACT FROM AUTHOR]

• 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]

While climate scientists have developed high resolution data sets on the distribution of climate risks, we still lack comparable data on the local distribution of public climate change opinions. This paper provides the first effort to estimate local climate and energy opinion variability outside the United States. Using a multi-level regression and post-stratification (MRP) approach, we estimate opinion in federal electoral districts and provinces. We demonstrate that a majority of the Canadian public consistently believes that climate change is happening. Belief in climate change’s causes varies geographically, with more people attributing it to human activity in urban as opposed to rural areas. Most prominently, we find majority support for carbon cap and trade policy in every province and district. By contrast, support for carbon taxation is more heterogeneous. Compared to the distribution of US climate opinions, Canadians believe climate change is happening at higher levels. This new opinion data set will support climate policy analysis and climate policy decision making at national, provincial and local levels. [ABSTRACT FROM AUTHOR]

Accurate estimation of greenhouse gas emissions and detailed monitoring of the carbon cycle are important for mitigation of and adaptation to climate change. On agricultural land, annual herbaceous vegetation is not considered a carbon sink, whereas perennial woody vegetation accumulates biomass over multiple years and does represent a carbon sink. This paper presents a study to estimate aboveground woody carbon stock in 1990 and its annual change from 1990 to 2000 on Canada’s cropland. The cropland was stratified into zones according to soils, climate and cropping systems, within which sample plots were randomly selected and paired aerial photographs corresponding to circa 1990 and 2000 were interpreted to detect changes in perennial woody vegetation such as trees, shrubs, orchards and vineyards. Woody biomass volumes lost as a result of land use change and gained as a result of planting and growth were estimated using species composition and growth rates typical of each zone, as obtained from published literature, forest reports and charts and forestry expert knowledge. Census of agriculture data was used to scale up the sample level results to zone and national levels. Results showed that on Canada’s cropland, the aboveground woody carbon stock in 1990 was 33.7 ± 8.8 Tg. Between 1990 and 2000, the area covered by woody vegetation was affected negatively by removals and positively through planting and natural regeneration, leading to a net reduction in area. There was an annual increase of about 78.3 Gg over all cropland in Canada, with a net decrease in some ecozones. Although this is a comparatively small increase with a large uncertainty, it indicates that changes in woody carbon on cropland in Canada over the 1990–2000 period were relatively insignificant. Further studies may be needed to refine the carbon estimates and reduce uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: Biochar production and mixing in soil are seen as the best options for atmospheric carbon sequestration, providing simultaneous benefits to soil and opportunities for distributed energy generation. The proximity of biomass source and biochar dispersal greatly reduces the energy and emissions footprint of the whole process. The viability of the whole biochar process is examined from two boundary points: is there enough biomass around to have significant impact on the atmospheric CO2 levels and is there enough soil area for biochar dispersal. The answers are soundly positive, both for the world as a whole and for Canada, for which a more detailed analysis was done. However, the massive adoption of biochar solution is critically dependent on proper recognition of its carbon sequestration impact its soil improvement potentials. To that extent the International Biochar Initiative, together with national chapters, including recently formed Canadian Biochar Initiative, are actively promoting biochar related research and policy framework. This paper addresses the questions of availability of sources and sites that would benefit from its dispersal. [Copyright &y& Elsevier]