• Energy Research
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Operationalizing a Global Carbon Observing and Analysis System (www.geocarbon.net) would provide a sound basis for monitoring actual carbon fluxes and thus getting quantities right when pricing carbon – be it in a cap-and-trade scheme or under a tax regime. However, such monitoring systems are expensive and—especially in times of economic weakness—budgets for science and environmental policy are under particular scrutiny. In this study, we attempt to demonstrate the magnitude of benefits of improved information about actual carbon fluxes. Such information enables better-informed policy-making and thus paves the way for a more secure investment environment when decarbonizing the energy sector. The numerical results provide a robust indication of a positive social value of improving carbon monitoring systems when compared to their cost, especially for the more ambitious climate policies.

The Paris Agreement introduced an ambitious goal of limiting warming to 1.5 °C above pre-industrial levels. Here we combine a review of modelled pathways and literature on mitigation strategies, and develop a land-sector roadmap of priority measures and regions that can help to achieve the 1.5 °C temperature goal. Transforming the land sector and deploying measures in agriculture, forestry, wetlands and bioenergy could feasibly and sustainably contribute about 30%, or 15 billion tonnes of carbon dioxide equivalent (GtCO2e) per year, of the global mitigation needed in 2050 to deliver on the 1.5 °C target, but it will require substantially more effort than the 2 °C target. Risks and barriers must be addressed and incentives will be necessary to scale up mitigation while maximizing sustainable development, food security and environmental co-benefits.

AbstractForests of the European Union (EU) have been intensively managed for decades, and they have formed a significant sink for carbon dioxide (CO2) from the atmosphere over the past 50 years. The reasons for this behavior are multiple, among them are: forest aging, area expansion, increasing plant productivity due to environmental changes of many kinds, and, most importantly, the growth rates of European forest having been higher than harvest rates. EU countries have agreed to reduce total emissions of GHG by 20% in 2020 compared to 1990, excluding the forest sink.A relevant question for climate policy is: how long will the current sink of EU forests be maintained in the near future? And could it be affected by other mitigation measures such as bioenergy? In this article we assess tradeoffs of bioenergy use and carbon sequestration at large scale and describe results of the comparison of two advanced forest management models that are used to project CO2 emissions and removals from EU forests until 2030. EFISCEN, a detailed statistical matrix model and G4M, a geographically explicit economic forestry model, use scenarios of future harvest rates and forest growth information to estimate the future carbon balance of forest biomass. Two scenarios were assessed: the EU baseline scenario and the EU reference scenario (including additional bioenergy and climate policies).Our projections suggest a significant decline of the sink until 2030 in the baseline scenario of about 25–40% (or 65–125 Mt CO2) compared to the models’ 2010 estimate. Including additional bioenergy targets of EU member states has an effect on the development of this sink, which is not accounted in the EU emission reduction target. A sensitivity analysis was performed on the role of future wood demand and proved the importance of this driver for the future sink development.

Abstract Even though enormous expectations for greenhouse gas mitigation in the land use sector exist at the same time worries about potential implications for sustainable development have been raised as many Sustainable Development Goals (SDGs) are closely tied to developments in the sector. Here we assess the implications of achieving selected key SDG indicators for Zero Hunger, Clean Water and Sanitation, Responsible Consumption and Production, and Life on Land on the land-based climate change mitigation potential. We find that protecting highly biodiverse ecosystems has profound impacts on biomass potentials (−30% at >12 US dollar per gigajoule) while other SDGs mainly affect greenhouse gas abatement potentials. Achieving SDGs delivers synergies with greenhouse gas abatement and may even in the absence of additional mitigation policies allow to realize up to 25% of the expected greenhouse gas abatement from land use required to stay on track with the 1.5 °C target until 2050. Future land use mitigation policies should consider and take advantage of these synergies across SDGs.

To keep global warming possibly below 1.5 °C and mitigate adverse effects of climate change, agriculture, like all other sectors, will have to contribute to efforts in achieving net negative emissions by the end of the century. Cost-efficient distribution of mitigation across regions and economic sectors is typically calculated using a global uniform carbon price in climate stabilization scenarios. However, in reality such a carbon price would substantially affect food availability. Here, we assess the implications of climate change mitigation in the land use sector for agricultural production and food security using an integrated partial equilibrium modelling framework and explore ways of relaxing the competition between mitigation in agriculture and food availability. Using a scenario that limits global warming cost-efficiently across sectors to 1.5 °C, results indicate global food calorie losses ranging from 110–285 kcal per capita per day in 2050 depending on the applied demand elasticities. This could translate into a rise in undernourishment of 80–300 million people in 2050. Less ambitious greenhouse gas (GHG) mitigation in the land use sector reduces the associated food security impact significantly, however the 1.5 °C target would not be achieved without additional reductions outside the land use sector. Efficiency of GHG mitigation will also depend on the level of participation globally. Our results show that if non-Annex-I countries decide not to contribute to mitigation action while other parties pursue their mitigation efforts to reach the global climate target, food security impacts in these non-Annex-I countries will be higher than if they participate in a global agreement, as inefficient mitigation increases agricultural production costs and therefore food prices. Land-rich countries with a high proportion of emissions from land use change, such as Brazil, could reduce emissions with only a marginal effect on food availability. In contrast, agricultural mitigation in high population (density) countries, such as China and India, would lead to substantial food calorie loss without a major contribution to global GHG mitigation. Increasing soil carbon sequestration on agricultural land would allow reducing the implied calorie loss by 65% when sticking to the initially estimated land use mitigation requirements, thereby limiting the impact on undernourishment to 20–75 million people, and storing significant amounts of carbon in soils.