The Potential of Carbon Storage in the Ocean as Bicarbonate

Bicarbonate (HCO3-) and carbonate (CO32-) ions in the ocean are a fundamental component of the global carbon cycle. The oceans contain approximately 38,000 billion tonnes of C as HCO3- and CO32- (40x that in the atmosphere) with fluxes between different parts of this reservoir on the order of \u3c1 GtC per year (Figure 1). Eventually, most of anthropogenic CO2 emitted to the atmosphere will be incorporated into this sink as a consequence of mineral weathering. Intentionally storing additional CO2 as HCO3- in the ocean has been suggested since the mid-90s (e.g., ocean liming, accelerated weathering of limestone, enhanced weathering), but estimates on storage potential, environmental impact, and technical feasibility remain poorly constrained. Our recent work has used the output of recent modelling studies in an attempt to estimate the carbon storage potential of this reservoir, and it is apparent that trillions of tonnes of CO2 can be stored with marginal changes in ocean chemistry when the impact is distributed globally. The changes are more acute around the points of addition, and vary with each technology. All proposals for ocean bicarbonate storage require the extraction, comminution, transport, and dissolution of silicate or carbonate rocks. While the global decadal scale-up of such an operation to impact the climate is not unprecedented, it raises questions regarding environmental and social acceptability. Please click Additional Files below to see the full abstract

Rethinking the impact of regeneration on poverty: a (partial) defence of a 'failed' policy

For decades regeneration programmes in England targeted areas where spatial concentrations of poverty exist. These 'area-based initiatives' (ABIs) came under sustained attack, however, from the previous coalition government for being expensive and ineffective. This paper assesses this claim by re-evaluating past evidence on the impact of regeneration on poverty. It finds regeneration did relatively little to transform households' material circumstances but significantly ameliorated negative experiences of living in poverty in relation to housing, community safety and the physical environment. This partially undermines the rationale for the policy shift away from neighbourhood renewal interventions toward the current focus on 'local growth' as the sole remedy for spatial inequalities. It also suggests a need for more nuance in wider critical accounts of regeneration as a deepening form of neoliberalism

The potential environmental response to increasing ocean alkalinity for negative emissions

The negative emissions technology, artificial ocean alkalinization (AOA), aims to store atmospheric carbon dioxide (CO2) in the ocean by increasing total alkalinity (TA). Calcium carbonate saturation state (ΩCaCO3) and pH would also increase meaning that AOA could alleviate sensitive regions and ecosystems from ocean acidification. However, AOA could raise pH and ΩCaCO3 well above modern-day levels, and very little is known about the environmental and biological impact of this. After treating a red calcifying algae (Corallina spp.) to elevated TA seawater, carbonate production increased by 60% over a control. This has implication for carbon cycling in the past, but also constrains the environmental impact and efficiency of AOA. Carbonate production could reduce the efficiency of CO2 removal. Increasing TA, however, did not significantly influence Corallina spp. primary productivity, respiration, or photophysiology. These results show that AOA may not be intrinsically detrimental for Corallina spp. and that AOA has the potential to lessen the impacts of ocean acidification. However, the experiment tested a single species within a controlled environment to constrain a specific unknown, the rate change of calcification, and additional work is required to understand the impact of AOA on other organisms, whole ecosystems, and the global carbon cycle

Assessing ocean alkalinity for carbon storage

Proposals to remove CO2 from the atmosphere are becoming increasingly important in climate change policy. However, considerable uncertainty remains regarding the cost, scalability, and socioenvironmental consequences. One proposal for removing CO2 from the atmosphere involves increasing total alkalinity (TA) in the ocean. This is known as ocean alkalinity enhancement (OAE) and involves the oceanic uptake of CO2 from the atmosphere and its’ conversion to carbonate (CO3 2- ) or bicarbonate (HCO3 - ) ions. Increasing ocean TA, pH, and calcium carbonate saturation state (ΩCaCO3) could potentially alleviate sensitive ecosystems from ocean acidification. However, OAE could raise pH and ΩCaCO3 well above modern day levels and there is little data on the environmental impact of this. These potential perturbations could substantially influence marine biology, particularly those taxa found in coastal environments as these regions are a favourable site for TA addition. This thesis sets out to determine how elevated TA influences the physiology of two important coastal taxa, a benthic calcifying macroalgae found on rocky shores of the continental shelf (Corallina spp.) and Synechococcus 8806, a calcifying pico-sized phytoplankton found in the surface of deeper continental shelf waters. How elevated TA affects the growth rates, calcification rates, productivity rates and photophysiology of these two physiologically different species was investigated as part of four separate ex-situ experiments. The results from this thesis provide the first insights to the practical use of OAE as a carbon dioxide removal approach in terms of the response of the marine environment. Results show that increasing seawater TA significantly increases Corallina spp. calcification rates and productivity rates and so could potentially lessen the impacts of ocean acidification. Furthermore, these results suggest that elevated TA increases Synechococcus 8806 growth and under elevated TA higher rates of CaCO3 precipitation rates occurred. However, the results from this thesis do not show whether this was due to Synechococcus 8806 growth. The results show that OAE would not be intrinsically detrimental for Corallina spp. and Synechococcus 8806 in terms of direct effects to physiology. However, further research is needed to determine what the indirect effects of elevated TA are and how this could impact Corallina spp. and Synechococcus 8806

Residential school placements for children and young people with intellectual disabilities: their use and implications for adult social care

Out of area residential placements are associated with a range of poor outcomes for adults with intellectual disabilities and behaviours that challenge. In recent years there has been an increased drive to reduce such placements at as early a stage as possible. In this context the current review collates research and policy regarding use of residential schools for children and young people with intellectual disabilities and transition from these settings to adult services. The review highlights that relatively little is known about both use of, and transition from, residential schooling for children and young people with intellectual disabilities in the UK. Thirteen articles are identified: 7 examining the child or families’ experiences before placement, 4 examining outcomes during the placement, and 4 examining the process of transitioning from the placement and longer term outcomes. The methodological quality of articles was often limited. A lack of control groups, independent samples, or adequate sample sizes was particularly notable. Results are discussed in relation to factors that lead to a child’s placement in a residential school, children and families’ experiences of the placement, and outcomes following placement, including the transition process. A number of research priorities are highlighted based on gaps in the literature. Examples of alternative forms of support from clinical practice are provided, with recognition that a multi-element model is likely to be needed to provide high quality support to this group of young people