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This paper aims to present a computationally efficient finite element model for the simulation of isothermal immiscible two-phase flow in a rigid porous media with a particular application to CO₂ sequestration in underground formations. Focus is placed on developing a numerical procedure, which is effectively mesh-independent and suitable to problems at regional scales.

The averaging theory is utilized to describe the governing equations of the involved unsaturated multiphase flow. The level-set (LS) method and the extended finite element method (XFEM) are utilized to simulate flow of the CO₂ plume. The LS is employed to trace the plume front. A streamline upwind Petrov-Galerkin method is adopted to stabilize possible occurrence of spurious oscillations due to advection. The XFEM is utilized to model the high gradient in the saturation field front, where the LS function is used for enhancing the weighting and the shape functions.

The capability of the proposed model and its features are evaluated by numerical examples, demonstrating its accuracy, stability and convergence, as well as its advantages over standard and upwind techniques. The study showed that a good combination between a mathematical model and a numerical model enables the simulation of complicated processes occurring in complicated and large geometry using minimal computational efforts.

A new computational model for two-phase flow in porous media is introduced with basic requirements for accuracy, stability, and convergence, which are met using relatively coarse meshes.

The authors aim to investigate the ability of a New Zealand university to rely on the CO₂ sequestered in the trees on campus to mitigate the CO₂ emissions caused by operations.

The authors count and measure the trees on the university's 68 hectare main campus, ignoring smaller trees that sequester very little CO₂.

The authors estimate that the 4,139 trees the authors count contain 5,809 tonnes of CO₂. The authors further estimate the additional CO₂ sequestration over the next ten years to be 253 tonnes per year. The university's annual CO₂ emissions were 4,086 tonnes in 2011. More than 70 per cent of this amount relates to overseas travel. Therefore, CO₂ sequestration in trees promises to mitigate only about 6 per cent of total emissions over the next ten years.

This suggests that other initiatives will be needed if the university is serious about reducing its greenhouse gas emissions impact. An obvious avenue appears to be to reduce overseas travel, e.g. by finding different ways for academic staff to network and obtain feedback on their research. Other universities and other organisations starting to investigate their environmental impact are likely to similarly find that CO₂ sequestration in trees can only provide limited mitigation opportunities.

The authors contribute to the ongoing debate around carbon emissions, exploring avenues to mitigate CO₂ emissions.

This paper aims to explore three operations and supply chain management (OSCM) approaches for meeting the 2 °C targets to counteract climate change: adaptation (adjusting to climatic impacts); mitigation (innovating towards low-carbon practices); and carbon-removing negative emissions technologies (NETs). We suggest that adaptation nor mitigation may be enough to meet the current climate targets, thus calling for NETs, resulting in the following question: How can operations and supply chains be reconceptualized for NETs?

We draw on the sustainable supply chain and transitions discourses along with interview data involving 125 experts gathered from a broad research project focused on geoengineering and NETs. We analyze three case studies of emerging NETs (biochar, direct air carbon capture and storage and ocean alkalinity enhancement), leading to propositions on the link between OSCM and NETs.

Although some NETs are promising, there remains considerable variance and uncertainty over supply chain configurations, efficacy, social acceptability and potential risks of unintended detrimental consequences. We introduce the concept of transformative OSCM, which encompasses policy interventions to foster the emergence of new technologies in industry sectors driven by social mandates but lack clear commercial incentives.

To the best of the authors’ knowledge, this paper is among the first that studies NETs from an OSCM perspective. It suggests a pathway toward new industry structures and policy support to effectively tackle climate change through carbon removal.

Sustainable atmospheric management today involves a complex set of issues arising from the deliberate or inadvertent use of the atmosphere as a repository for waste products arising from human activities. Urban pollution affects human health, building materials and vegetation. Acidic emissions and excess nutrients produce both acid rain and dry deposition that affect terrestrial, freshwater and ocean chemistry and ecosystems. The production and effects of atmospheric pollution can transcend national boundaries and thus mitigation will require cooperation on regional and global levels, as well as local action. Global pollution includes greenhouse gases and atmospheric particles which are changing the global climate and affecting human health. While technological solutions will play an important part, the large reductions in emissions necessary to achieve sustainability will involve adopting lifestyles that conserve energy and minimise pollution. These concerns were foreshadowed in the writings of Fritz Schumacher.

Emission reduction methodologies alone are not sufficient to mitigate the climatic catastrophes caused due to ongoing carbon emissions. Rather, a bidirectional approach is required to decarbonize the excess carbon in the atmosphere through carbon sequestration along with carbon reduction. Since the manufacturing sector contributes heavily to the ongoing carbon emissions, the purpose of this paper is to propose a framework for carbon emission reduction and carbon sequestration in the context of the manufacturing industry.

In this paper, life cycle assessment (LCA) is employed to track the carbon emission at each stage of the product development life cycle. The pre-requisite for this is the accurate evaluation of the carbon emissions. Therefore, IoT technologies have been employed for collecting real-time data with high credibility to perceive environmental impact caused during the entire life cycle of the product. The total carbon emission calculation is based on the bill of material (BOM)-based LCA of the product to realize the multi-structure (from parts and components to product) as well as multi-stage (from cradle to gate) carbon emission evaluation. Carbon sequestration due to plantation is evaluated using root-shoot ratio and total biomass.

A five interwoven layered structure is proposed in the paper to facilitate the real-time data collection and carbon emission evaluation using BOM-based LCA of products. Further, a carbon neutral coefficient (CNC) is proposed to indicate the state of a firm’s carbon sink and carbon emissions. CNC=1 indicates that the firm is carbon neutral. CNC >1 implies that the firm’s carbon sequestration is more than carbon emissions. CNC <1 indicates that the firm’s carbon emission is more than the carbon sink.

The paper provides a novel framework which integrates the real-time data collection and evaluation of carbon emissions with the carbon sequestration.

This paper aims to assess factors that affect carbon sequestration on green roofs.

The most current academic literature related to carbon sequestration and green roofs carbon sequestration performance was reviewed.

Factors affecting carbon sequestration were discussed and classified into the following factors: plants, physical and maintenance factors. The authors’ findings are significant because they can be used to optimize green roofs performance for carbon sequestration.

Factors affecting carbon sequestration will optimize intensive green roofs performance.

In this work, it is presented a locally conservative multiscale algorithm accounting the mineralization process during the supercritical carbon dioxide injection into a deep saline aquifer. The purpose of this study is to address numerically the geological storage of CO₂ in a highly heterogeneous reservoir, leading with interactions among several phenomena in multiple scales.

This algorithm have features that distinguish it from the presently available solvers which are: (i) an appropriate combination of a coupled transport system solver using a high-order non-oscillatory central-scheme finite volume method and, elliptic numerical approach applying a locally conservative finite element method for Darcy’s law and, (ii) the capability of leading with interactions among several phenomena in multiple scales.

As a result, this approach was able to quantify the precipitation of the carbonate crystals at the solid interface.

The University of Michigan (U-M) is planning its course toward carbon neutrality. A key component in U-M carbon accounting is the calculation of carbon sinks via estimation of carbon storage and biosequestration on U-M landholdings. Here, this paper aims to compare multiple remote sensing methods across U-M natural lands and urban campuses to determine the accurate and efficient protocol for land assessment and ecosystem service valuation that other institutions may scale as relevant.

This paper tested three remote sensing methods to determine land use and land cover (LULC), namely, unsupervised classification, supervised classification and supervised classification incorporating delineated wetlands. Using confusion matrices, this paper tested remote sensing approaches to ground-truthed data, the paper obtained via field-based vegetation surveys across a subset of U-M landholdings.

In natural areas, supervised classification incorporating delineated wetlands was the most accurate and efficient approach. In urban settings, maps incorporating institutional knowledge and campus tree surveys better estimated LULC. Using LULC and literature-based carbon data, this paper estimated that U-M lands store 1.37–3.68 million metric tons of carbon and sequester 45,000–86,000 Mt CO₂e/yr, valued at $2.2m–$4.3m annually ($50/metric ton, social cost of carbon).

This paper compared methods to identify an efficient and accurate remote sensing methodology to identify LULC and estimate carbon storage, biosequestration rates and economic values of ecosystem services provided.

The purpose of this paper is to provide a linguistic perspective for corporate brochures. Corporate brochures are published to introduce an organization and to provide information about it but the brochures have been claimed to include promotional elements. By conducting a genre analysis the paper aims to confirm that genre-based writing is not formulaic but instead demonstrates versatility and creativity.

Corporate brochures from a specific industry, oil and gas were sourced from the websites and a total of 16 were available. The method of analysis was genre analysis to establish the generic structure of the brochures by examining the rhetorical moves and strategies, and to identify the textual features of the texts to explain why they are written the way they are.

The oil and gas brochures display a five-move generic structure with a number of strategies. The moves show high occurrence proving the industry as a specialized one. Although the moves are the same, the contents are varied. Versatility is also seen in the presentation style in terms of form, content and language.

Findings on generic structure and textual features of brochures can be used as a guide for corporate writers, as well as trainees and students of corporate communication.

The data for this research represent one industry which has not been explored before thus contributing to the body of knowledge in the field of genre analysis. Although generic in form, genre-based writing has proven to be versatile. The textual features show how companies project their corporate image via brochures.

The aim of this study is to numerically simulate the density-driven convection in heterogeneous porous media associated with anisotropic permeability field, which is important to the safe and stable long term CO₂ storage in laminar saline aquifers.

The study uses compact finite difference and the pseudospectral method to solve Darcy’s law.

The presence of heterogeneous anisotropy may result in non-monotonic trend of the breakthrough time and quantity of CO₂ dissolved in the porous medium, which are important to the CO₂ underground storage.

The manuscript numerically study the convective phenomena of mixture contained CO₂ and brine. The phenomena are important to the process of CO₂ enhanced oil recovery. Interesting qualitative patterns and quantitative trends are revealed in the manuscript.