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As disruptions from climate change increase, so will the urgency to find shorter-term approaches to ameliorating its harms. This may include calls to implement solar geoengineering, an approach to cooling the planet by reflecting incoming sunlight back to space. While the exact effects of solar geoengineering are still highly uncertain, physical science to date suggests that it may be effective at reducing many aspects of climate change in the short term. One of the biggest concerns about solar geoengineering is the extent to which it may interfere with crucial emissions reductions policies, i.e. mitigation. There are multiple channels by which geoengineering could alter mitigation pathways, both financial and behavioural. Here we define three such linkages and present the evidence available to constrain their potential magnitudes. Because solar geoengineering is not a substitute for mitigation, policies to develop or implement technologies that could be used to carry it out should be designed to accentuate its complementary nature to mitigation and deter the possibility it is used to delay decarbonizing the economy. [ABSTRACT FROM AUTHOR]

Climate Change 2021: The Physical Science Basis; AR6, WG1, Cambridge University Press: Cambridge, UK. 2021 6 Intergovernmental Panel on Climate Change (IPCC). They conclude that a future powered by RE may be possible but caution that future global population growth [[23]] will make such a future progressively more difficult to attain - or sustain - into the future. The first report of the Intergovernmental Panel on Climate Change (IPCC) was produced in 1990 and warned of the dangers of global climate change. The situation is bad but could worsen if the drivers of climate change (CC), greenhouse gas emissions (GHGs), and land-use changes, including net deforestation, are not rapidly reduced. [Extracted from the article]

While the Intergovernmental Panel on Climate Change (IPCC) physical science reports usually assess a handful of future scenarios, the Working Group III contribution on climate mitigation to the IPCC's Sixth Assessment Report (AR6 WGIII) assesses hundreds to thousands of future emissions scenarios. A key task in WGIII is to assess the global mean temperature outcomes of these scenarios in a consistent manner, given the challenge that the emissions scenarios from different integrated assessment models (IAMs) come with different sectoral and gas-to-gas coverage and cannot all be assessed consistently by complex Earth system models. In this work, we describe the "climate-assessment" workflow and its methods, including infilling of missing emissions and emissions harmonisation as applied to 1202 mitigation scenarios in AR6 WGIII. We evaluate the global mean temperature projections and effective radiative forcing (ERF) characteristics of climate emulators FaIRv1.6.2 and MAGICCv7.5.3 and use the CICERO simple climate model (CICERO-SCM) for sensitivity analysis. We discuss the implied overshoot severity of the mitigation pathways using overshoot degree years and look at emissions and temperature characteristics of scenarios compatible with one possible interpretation of the Paris Agreement. We find that the lowest class of emissions scenarios that limit global warming to "1.5 ∘ C (with a probability of greater than 50 %) with no or limited overshoot" includes 97 scenarios for MAGICCv7.5.3 and 203 for FaIRv1.6.2. For the MAGICCv7.5.3 results, "limited overshoot" typically implies exceedance of median temperature projections of up to about 0.1 ∘ C for up to a few decades before returning to below 1.5 ∘ C by or before the year 2100. For more than half of the scenarios in this category that comply with three criteria for being "Paris-compatible", including net-zero or net-negative greenhouse gas (GHG) emissions, median temperatures decline by about 0.3–0.4 ∘ C after peaking at 1.5–1.6 ∘ C in 2035–2055. We compare the methods applied in AR6 with the methods used for SR1.5 and discuss their implications. This article also introduces a "climate-assessment" Python package which allows for fully reproducing the IPCC AR6 WGIII temperature assessment. This work provides a community tool for assessing the temperature outcomes of emissions pathways and provides a basis for further work such as extending the workflow to include downscaling of climate characteristics to a regional level and calculating impacts. [ABSTRACT FROM AUTHOR]

The increase in simulated flood inundation areas and depths (6%-31% for different GCMs) in the future showed the importance of improving flood management tools for the sustainable development of urban water environments. The paper by Burch et al. (2010) addresses a different aspect of flood risk management in response to climate change and illustrates an advance in best practice for flood risk management and climate change planning. In terms of flood risk management, NBSs include natural flood management measures (NFMs), and these are the subject of the paper in this VSI by Dittrich et al. (2019). [Extracted from the article]

The article presents the discussion on fundamental change in organizing the social provisioning systems. Topics include typically associated with a strong role for public leadership and a simultaneous consideration of ecological and social goals; and demand-side mitigation reducing the dependence on negative emission technologies.

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.

Here, we provide additional context around the claims by Samset et al.[1] of multi-decadal delays of mitigation benefits and express concerns with their conceptual approach towards assessing a discernible warming response under different greenhouse gas concentration pathways. Blue dots indicate the minimal sample size for which a given temperature difference is detected by 66% of the pairs at a 0.05 significance level, the significance threshold chosen by Samset et al.[1] The area right of the blue dots is the area for which temperature differences can be detected. The Representative Concentration Pathways (RCPs) deployed by Samset et al.[1], are distinct greenhouse gas concentration pathways, and consequently, differences in their mean warming response as modelled by the reduced-complexity climate model MAGICC are evident in Fig. [Extracted from the article]

We welcome a broader debate on this aspect of global responses to climate change, attempt to reconcile our views in the following. B replying to b A. Lanson et al. I Nature Communications i https://doi.org/10.1038/s41467-022-31425-x (2022) In response to our recent paper[1] (hereafter SFL20) concerning the relation between natural variability in the climate system and the time to detect a response to emissions mitigation, Lanson et al.[2] (hereafter L22) call for 'a broader debate on how to best assess and communicate emerging effects of climate mitigation in the light of natural variability'. It is still efficient in revealing differences between the rapid climate response to aerosol perturbations, similar to the idealized test performed by L22, and the slower evolution from e.g. CO2 emissions. [Extracted from the article]

However, although historically their emissions have been great, most of the developed economies decoupled their carbon emissions and economic growth with the decarbonizing industry, and peaked their emissions by the first decade of this century [[2]]. Although theoretically these countries emit much less CO SB 2 sb , they appear to be more sensitive and susceptible to climate change, and it is very difficult for academics to conduct thorough studies in order to understand their emission baselines and track their climate change mitigation efforts. Therefore, their work advocates international assistance for these emerging emitters and reveals the important role of historically major emitters in addressing global climate change, not only to provide technical and financial assistance to reduce emissions, but also to prioritize their own emission reduction agenda. [Extracted from the article]