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Scenarios avoiding global warming greater than 1.5 or 2 ∘C, as stipulated in the Paris Agreement, may require the combined mitigation of anthropogenic greenhouse gas emissions alongside enhancing negative emissions through approaches such as afforestation–reforestation (AR) and biomass energy with carbon capture and storage (BECCS). We use the JULES land surface model coupled to an inverted form of the IMOGEN climate emulator to investigate mitigation scenarios that achieve the 1.5 or 2 ∘C warming targets of the Paris Agreement. Specifically, within this IMOGEN-JULES framework, we focus on and characterise the global and regional effectiveness of land-based (BECCS and/or AR) and anthropogenic methane (CH4) emission mitigation, separately and in combination, on the anthropogenic fossil fuel carbon dioxide (CO2) emission budgets (AFFEBs) to 2100. We use consistent data and socio-economic assumptions from the IMAGE integrated assessment model for the second Shared Socioeconomic Pathway (SSP2). The analysis includes the effects of the methane and carbon–climate feedbacks from wetlands and permafrost thaw, which we have shown previously to be significant constraints on the AFFEBs. Globally, mitigation of anthropogenic CH4 emissions has large impacts on the anthropogenic fossil fuel emission budgets, potentially offsetting (i.e. allowing extra) carbon dioxide emissions of 188–212 Gt C. This is because of (a) the reduction in the direct and indirect radiative forcing of methane in response to the lower emissions and hence atmospheric concentration of methane and (b) carbon-cycle changes leading to increased uptake by the land and ocean by CO2-based fertilisation. Methane mitigation is beneficial everywhere, particularly for the major CH4-emitting regions of India, the USA, and China. Land-based mitigation has the potential to offset 51–100 Gt C globally, the large range reflecting assumptions and uncertainties associated with BECCS. The ranges for CH4 reduction and BECCS implementation are valid for both the 1.5 and 2 ∘C warming targets. That is the mitigation potential of the CH4 and of the land-based scenarios is similar for regardless of which of the final stabilised warming levels society aims for. Further, both the effectiveness and the preferred land management strategy (i.e. AR or BECCS) have strong regional dependencies. Additional analysis shows extensive BECCS could adversely affect water security for several regions. Although the primary requirement remains mitigation of fossil fuel emissions, our results highlight the potential for the mitigation of CH4 emissions to make the Paris climate targets more achievable.

Human land use activities have resulted in large changes to the biogeochemical and biophysical properties of the Earth's surface, with consequences for climate and other ecosystem services. In the future, land use activities are likely to expand and/or intensify further to meet growing demands for food, fiber, and energy. As part of the World Climate Research Program Coupled Model Intercomparison Project (CMIP6), the international community has developed the next generation of advanced Earth system models (ESMs) to estimate the combined effects of human activities (e.g., land use and fossil fuel emissions) on the carbon–climate system. A new set of historical data based on the History of the Global Environment database (HYDE), and multiple alternative scenarios of the future (2015–2100) from Integrated Assessment Model (IAM) teams, is required as input for these models. With most ESM simulations for CMIP6 now completed, it is important to document the land use patterns used by those simulations. Here we present results from the Land-Use Harmonization 2 (LUH2) project, which smoothly connects updated historical reconstructions of land use with eight new future projections in the format required for ESMs. The harmonization strategy estimates the fractional land use patterns, underlying land use transitions, key agricultural management information, and resulting secondary lands annually, while minimizing the differences between the end of the historical reconstruction and IAM initial conditions and preserving changes depicted by the IAMs in the future. The new approach builds on a similar effort from CMIP5 and is now provided at higher resolution (0.25∘×0.25∘) over a longer time domain (850–2100, with extensions to 2300) with more detail (including multiple crop and pasture types and associated management practices) using more input datasets (including Landsat remote sensing data) and updated algorithms (wood harvest and shifting cultivation); it is assessed via a new diagnostic package. The new LUH2 products contain > 50 times the information content of the datasets used in CMIP5 and are designed to enable new and improved estimates of the combined effects of land use on the global carbon–climate system.

Background and purpose: Complaints about side-effects of antiepileptic drugs (AEDs) may be overlooked in clinical practice. We assessed the value and risks of an active intervention policy for reported complaints in a randomized controlled pragmatic trial. Methods: This randomized controlled pragmatic trial included 111 adults treated for epilepsy in seven general hospitals. They were considered well-managed by their treating physician, but reported moderate to severe complaints on a questionnaire (SIDAED, assessing SIDe effects in AED treatment). The intervention was adjustment of AED treatment (53 patients), either reduction of dose or switch of AED, versus continuation of treatment unchanged (58 control patients) during 7 months. Primary outcomes were quality of life (Qolie-10) and complaints score. Secondary outcome measures were the occurrence of seizures or adverse events. Results: After 7 months, the relative risk (RR) for improvement in quality of life was 1.80 (1.04-3.12) for the intervention group compared to control and the RR of decrease in complaints was 1.34 (0.88-2.05). In 58% of patients randomized to adjustment, the medication had indeed been changed. Discussion: In conclusion, despite a possible risk of seizure recurrence, adjustment of drug treatment in well-managed patients with epilepsy, who report considerable complaints, improves the quality of life.

Summary Objectives Side-effects of anti-epileptic drugs (AEDs) may be overlooked in patients with epilepsy in everyday clinical practice. The aim of this study was to assess the prevalence and severity of subjective complaints in patients who were considered to be well-controlled and to assess whether these complaints are related to medication, personality traits, or other determinants. Methods We included patients with epilepsy who were considered to be well-controlled in a cross-sectional study in seven hospitals in the Netherlands. Their medication had not been changed for six months and an apparent reason to change the medication was lacking at the time of enrolment. Subjective complaints were assessed with a 46-item questionnaire. Using multivariable linear regression modeling, we assessed whether patient characteristics, epilepsy characteristics, medication, quality of life (Qolie-10), and personality traits (SCL-90) explained the presence and severity of complaints. Results Of 173 included patients, 67% reported moderate to severe subjective complaints on the questionnaire. Cognitive complaints were reported most frequently. Multivariate modeling showed that 61% of the variance in reported complaints could be explained by included determinants. The prevalence and severity of complaints was associated with AED polytherapy and higher scores on psycho neuroticism. Conclusions Patients who were considered to be well-controlled proved to report an unexpectedly high number of subjective complaints. Both medication and aspects of personality contributed to the level of complaints. Our study illustrates that subjective side-effects are easily overlooked in everyday clinical practice, possibly because in practice a generally phrased question is used to detect side-effects.