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The article focuses on the importance of establishing a regionally focused and coordinated carbon dioxide removal (CDR) science-policy platform in southern Africa. The topics include the significance of CDR in steering the planet towards a safe climate, the challenges and opportunities associated with CDR interventions, and the need for governance mechanisms, technologies, and scientific capabilities to support CDR development.

The article focuses on the Intergovernmental Panel on Climate Change (IPCC) Assessment Report Six (AR6) Working Group I (WG1) report focus on the assessment of the global climate-carbon system with implications for adaptation and mitigation action in southern Africa. It mentions climate change attribution science is capable of quantifying the role of human influence in the occurrence of individual weather events.

This study was undertaken to characterise the seasonal cycle of air-sea fluxes of carbon dioxide (CO2) in the southern Benguela upwelling system off the South African west coast. Samples were collected from six monthly cross-shelf cruises in the St. Helena Bay region during 2010. CO2 fluxes were calculated from pCO2 derived from total alkalinity and dissolved inorganic carbon and scatterometer-based winds. Notwithstanding that it is one of the most biologically productive eastern boundary upwelling systems in the global ocean, the southern Benguela was found to be a very small net annual CO2 sink of -1.4 ± 0.6 mol C/m2 per year (1.7 Mt C/year). Regional primary productivity was offset by nearly equal rates of sediment and sub-thermocline remineralisation flux of CO2, which is recirculated to surface waters by upwelling. The juxtaposition of the strong, narrow near-shore out-gassing region and the larger, weaker offshore sink resulted in the shelf area being a weak CO2 sink in all seasons but autumn (-5.8, 1.4 and -3.4 mmol C/m2 per day for summer, autumn and winter, respectively). [ABSTRACT FROM AUTHOR]

Carbon dioxide plays a central role in earth's atmospheric, ocean and terrestrial systems.1,2 About 40% of the total anthropogenic emissions since 1750 have remained in the atmosphere, with the balance being removed by the ocean and vegetation sinks.3 Increasing atmospheric CO2 concentrations have been well documented,3 as have widespread impacts on human and natural systems, such as warmer surface temperatures, ocean warming and decreasing pH, loss of ice mass over the cryosphere, increasing global mean sea level, and alterations in the global hydrological cycle.3,4 The impact of increased atmospheric concentrations of CO2 on the biosphere includes shifting species extent, seasonal activities, migration patterns and abundances, as well as changes in species interactions. Monitoring of atmospheric CO2 and other greenhouse gases (GHGs) has been identified as a priority by international agencies, such as the United Nations Framework Convention on Climate Change and government departments that are interested in mitigating the effects of climate change. South Africa has made a commitment to a low carbon future as part of its role in global climate policy instruments through a national low carbon development strategy.5,6 At the Conference of the Parties in November 2015 (COP21), high level of agreement by developed and developing countries encouraged stakeholders to urgent action to address climate change. The agreement emphasises the urgent mitigation pledges with respect to GHG emissions by 2020. As South Africa implements its White Paper on Climate Change, to stimulate a shift towards a low carbon economy, it faces a monitoring and evaluation challenge. Currently, the South African GHG emission inventory is based on fossil fuel emissions, as part of the National Atmospheric Emissions Inventory System, under the National Air Quality Act, 2004 (Act No. 39 of 2004). Briefly, emissions are rarely measured directly, but rather based on proxy estimates of activity, extrapolated by an emission factor for the specific activity. There is therefore a need to independently assess the effectiveness of emissions reductions within the context of natural CO2 fluxes. Understanding the changing driving forces of climate change and evaluation of the carbon emission reduction activities requires long-term and high-precision measurements of CO2 gas emissions and sinks as well as their evolution. Land can act as both a source and a sink for GHGs.7 Currently the baseline GHG emissions from land and agriculture are thought to amount to 3.03x1010 kg CO2 eq per year in South Africa. The land sector is responsible for an uptake of 2.1x1010 kg CO2 eq per year while agriculture is responsible for a release of 5.06x1010 kg CO2 eq per year.7 The GHG emissions for South African industry amounted to ~5.45x1011 kg CO2 eq in 20108,9, with approximately 79% from the energy sector -- an order of magnitude larger than the emissions from agriculture7. Under the proposed White Paper policy, South Africa's GHG peak, plateau and decline trajectory anticipates emissions to peak at 6.1x1011 kg CO2 eq between 2020 and 2025, plateau at this range for about 10 years and decline to ~4.3x1011 kg CO2 eq by 2050.6 Determining these fluxes accurately will facilitate assessment of the proposed commitments to mitigation and adaptation strategies adopted by South Africa. At present there is infrastructure deployed in South Africa for the measurement of the concentrations and fluxes of CO2, which include observations in the atmosphere, on land and in the ocean. [ABSTRACT FROM AUTHOR]