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Following the Paris Agreement, virtually all countries worldwide have committed themselves to undertaking efforts to limit global warming to 1.5 °C. Within the European Union (EU), the recent ‘Fit for 55’ policy package proposes ambitious greenhouse gas (GHG) mitigation policies for all sectors as part of the EU's contribution to limiting global warming. Yet, it is unclear whether the proposed policies are sufficient for the EU to limit global warming to 1.5 °C and it remains an open policy problem how to translate global temperature targets into sector-specific emission budgets and further into sector-specific policies. Here, we derive GHG budgets for transport in EU27 and obtain GHG mitigation pathways for Europe consistent with 1.5 °C global warming. We do not provide a comprehensive assessment of the ‘Fit for 55’ transport package but we discuss the main policies for road transport in light of the GHG emission budgets, their level of ambition, and suggest amendments to these policies as well as improvements to the ‘Fit for 55’ package. Our results suggest that parts of the ‘Fit for 55’ for transport are still not ambitious enough to align with a 1.5 °C scenario. Key policy insightsA Paris-compatible residual carbon budget for EU transport is 10–12 Gt CO2.The budget implies net zero emissions for EU transport by 2044–2048 latest.We find the current ‘Fit for 55’ proposal for transport is not ambitious enough.A faster phase-out of cars and trucks with combustion engines is required and there is a need for ambitious standards for fast charging e-vehicles.CO2 pricing of transport is not a substitute but a complement to fleet targets. A Paris-compatible residual carbon budget for EU transport is 10–12 Gt CO2. The budget implies net zero emissions for EU transport by 2044–2048 latest. We find the current ‘Fit for 55’ proposal for transport is not ambitious enough. A faster phase-out of cars and trucks with combustion engines is required and there is a need for ambitious standards for fast charging e-vehicles. CO2 pricing of transport is not a substitute but a complement to fleet targets.

Drought and heat stress affect global wheat production and food security. Since these climate hazards are expected to increase in frequency and intensity due to anthropogenic climate change, there is a growing need for effective planning and adaptive actions at all timescales relevant to the stakeholders and users in this sector. This work aims at assessing the forecast quality in predicting the evolution of drought and heat stress by using user-relevant agro-climatic indices such as Standardized Precipitation Evapotranspiration Index (SPEI) and Heat Magnitude Day Index (HMDI) on a multi-annual timescale, as this time horizon coincides with the long-term strategic planning of stakeholders in the wheat sector. We present the probabilistic skill and reliability of initialized decadal forecast to predict these indices for the months preceding the wheat harvest on a global spatial scale. The results reveal the usefulness of the study in a climate services context while showing that decadal climate forecasts are skillful and reliable over several wheat harvesting regions. We would like to acknowledge financial support from the European Union’s Horizon 2020 Research and Innovation programme (MED-GOLD; Grant No. 776467, EUCP; Grant No. 776613 and FOCUS-Africa; Grant No. 869575) and from the Ministerio de Economía y Competitividad (MINECO) as part of the project CLINSA (Grant No. CGL2017-85791-R). This study has also received support from C3S_34c (contract number: ECMWF/COPERNICUS/2019/C3S_34c_DWD) of the Copernicus Climate Change Service (C3S) operated by ECMWF. B.S.M. acknowledges additional financial support from the Marie Sklodowska-Curie fellowship (Grant No. 713673) and from a fellowship of ’la Caixa’ Foundation (ID 100010434). The fellowship code is LCF/BQ/IN17/11620038.

There are multiple ways in which society can theoretically transition from its current carbon-intensive state to a zero-carbon future, ideally fast enough to limit global warming to 1.5oC above pre-industrial levels. Although the carbon budget associated with this temperature is close to being consumed (IPCC 2021), it still remains achievable - just. Furthermore, we know what needs to be done to achieve it, because we know what contributes to CO2 emissions. We need energy sources, whose carbon content results in emissions. Reducing both our demand for energy and its carbon intensity (by increasing the share of zero-carbon fuels in our energy mix) is thus of paramount importance. Some industrial manufacturing processes, particularly in cement production, produce CO2 as a chemical by-product. Capturing that CO2, finding alternative ways to produce cement, or reducing cement demand, is therefore necessary. Our agriculture, forestry and other land use (AFOLU) can be a net source or sink of CO2, so making it a large net sink by enhancing carbon dioxide removals (CDR), for example through afforestation, would help. And we hope to have available a range of human-made CDR technologies and measures, such as bioenergy with carbon capture and storage (BECCS), Direct Air Capture (DAC) and enhanced weathering (EW). Scaling these in an environmentally sustainable way would enhance our chances of keeping within the carbon budget. Finally, rapid progress in reducing short-lived greenhouse gases, particularly methane, would further help our chances of achieving 1.5oC.

Bioenergy development improves energy security and mitigates climate change. Because the stable supply of agricultural resources provides a solid basis for efficient bioenergy production, the climate-induced impacts such as changes in temperature and precipitation that potentially alter the farming decisions and cropping patterns should be taken into account. This study designs two-stage stochastic programming with recourse model to investigate the net bioenergy production and emission reduction, as well as the bioenergy producers’ strategies under various market operations and climate scenarios. The results show that the net production of biopower and biofuel are relatively stable because the supply of bioenergy feedstocks could remain at a constant level, but the farming decisions, cropping pattern, and resource utilization are likely to be altered by climate-induced impacts. The results also indicate that for efficient bioenergy production, approximately 41.5 billion TWD (9.65 billion CNY) and 33.6 billion TWD (7.81 billion CNY) of bond principal should be invested in crop-based and residual-based technology, respectively. In the face of strict environmental regulations and emission management, biopower technology becomes more competitive, and under such a circumstance, more than 98.3% of the low-cost bond should be invested in biopower development to achieve development efficiency.

Industrial clusters are considered more resource- and greenhouse gas-efficient than stand-alone industrial plants, but clustering may also act as a barrier to radical changes required for deep greenhouse gas emission reductions. Here we explore how clustering in an energy-intensive chemical industry cluster may influence attainability of the deep emission reduction targets. Chemelot, located in the southeast of the Netherlands, was willing to collaborate and we adopt a qualitative system dynamics approach based on expert interviews and group model building sessions. We found that clustering may hinder reaching deep emission reductions by three reinforcing feedback mechanisms, or ���traps���, related to: incremental changes; short-term focus; and companies acting alone. The system dynamics analysis also identified potential mechanisms to escape from these traps, notably: (1) increasing cluster autonomy; (2) activating public support; (3) promoting changes in the supply chain; and (4) attracting long-term investors. The findings can inform policymakers on how to steer industrial clusters towards deep emission reductions, and support industrial cluster decision-makers on both internal and external strategies. Key policy insightsIndustrial clustering may offer opportunities to accelerate deep greenhouse gas emission reductions, but it could also cause carbon lock-in because of increased physical and organizational interdependency, which favours incremental changes, short-term focus, and solitary actions rather than collective actions, at the cost of deep greenhouse gas emission reductions.To fully exploit the potential benefits of industrial clustering for greenhouse gas emission reductions, policies need to take into account the causal relations that operate in a self-reinforcing way to lock the cluster into high greenhouse gas emissions, and that can help escape them.A coordinating authority operating across the cluster is necessary to ensure effective collaboration within a chemical cluster so as to escape carbon lock-in.Policies addressing emissions along the full value chain (i.e. to include scope 3) might be mutually beneficial with the circularity and low-emission ambitions of the chemical industry. Industrial clustering may offer opportunities to accelerate deep greenhouse gas emission reductions, but it could also cause carbon lock-in because of increased physical and organizational interdependency, which favours incremental changes, short-term focus, and solitary actions rather than collective actions, at the cost of deep greenhouse gas emission reductions. To fully exploit the potential benefits of industrial clustering for greenhouse gas emission reductions, policies need to take into account the causal relations that operate in a self-reinforcing way to lock the cluster into high greenhouse gas emissions, and that can help escape them. A coordinating authority operating across the cluster is necessary to ensure effective collaboration within a chemical cluster so as to escape carbon lock-in. Policies addressing emissions along the full value chain (i.e. to include scope 3) might be mutually beneficial with the circularity and low-emission ambitions of the chemical industry.

The integration of solar energy into Germany's energy mix has multiplied over the last two decades. Therefore, it becomes increasingly important to quantify the spatiotemporal variations of solar energy to efficiently promote photovoltaic systems’ spatial spreading and strengthen the stability of power grids. Only comprehensive information on surface incoming solar radiation's long-term small-scale variability can provide the desired decision support. Clouds, and to some extent aerosols, are essentially responsible for the observed changes in solar energy penetrating the atmosphere. Germany was used as an example in this work, where solar energy currently accounts for around 8 % of annual electricity generation. The daily values of a 25 year dataset (1991–2015) available from satellite measurements were analyzed, depicting the long-term, large-scale evolution of the surface incoming solar radiation and cloud dynamics on a small spatial scale (0.05° × 0.05°). The most significant long-term increase in solar radiation was observed in spring, mainly influenced by the seasonal changes in cloud cover. The pronounced annual cycle of solar input reinforces the need for storage systems to transfer the harvested solar energy to periods with minor solar input. Moreover, there is hardly any solar-solar complementarity in different regions because their inter-regime dynamics are similar and do not show any significant differences. The proposed methods for assessing complementarity show explicitly the areas where the solar potential is not yet fully exploited, and additional PV capacities should be built. From these results, it can be concluded that there is further potential for the complementary use of solar energy in Germany on the national level.

Management of Earth's surface albedo is increasingly viewed as an important climate change mitigation strategy both on (Seneviratne et al., 2018) and off (Field et al., 2018; Kravitz et al., 2018) the land. Assessing the impact of a surface albedo change involves employing a measure like radiative forcing (RF) which can be challenging to digest for decision-makers who deal in the currency of CO2-equivalent emissions. As a result, many researchers express albedo change (Δα) RFs in terms of their CO2-equivalent effects, despite the lack of a standard method for doing so, such as there is for emissions of well-mixed greenhouse gases (WMGHGs; e.g., IPCC AR5, Myhre et al. (2013)). A major challenge for converting Δα RFs into their CO2-equivalant effects in a manner consistent with current IPCC emission metric approaches stems from the lack of a universal time-dependency following the perturbation (perturbation lifetime). Here, we review existing methodologies based on the RF concept with the goal of highlighting the context(s) in which the resulting CO2-equivalent metrics may or may not have merit. To our knowledge this is the first review dedicated entirely to the topic since the first CO2-eq. metric for Δα surfaced 20 years ago. We find that, although there are some methods that sufficiently address the time-dependency issue, none address or sufficiently account for the spatial disparity between the climate response to CO2 emissions and Δα – a major critique of Δα metrics based on the RF concept (Jones et al., 2013). We conclude that considerable research efforts are needed to build consensus surrounding the RF efficacy of various surface forcing types associated with Δα (e.g., crop change, forest harvest, etc.), and the degree to which these are sensitive to the spatial pattern, extent, and magnitude of the underlying surface forcings.

Private actors are important for urban climate action, because the public sector can control the carbon footprint of a city only partly. Public-private partnerships have been created through different voluntary approaches, such as city-level voluntary networks for companies with the aim to engage private actors in climate change mitigation and to support learning processes by bringing different actors together. If these processes are to happen, network members should connect with each other through voluntary networking activities. These connections can be studied using methods from network science. As a case example, we study the event-participationbased structures of the Climate Partners network of the City of Helsinki between 2011 and 2018, and develop an index to measure whether active event participation by a company is associated with taking more ambitious mitigation measures. The results show that the network manages to bring together companies from different fields but has difficulties with engaging them and encouraging ambitious climate goals. Our results can help to further develop networking activities. The tools we develop and share allow the replication of the analysis for other data sets, offering a basis for a comparative analysis of different networks. This opens new horizons for studying public-private networking and its effects. Funding Agencies|Tiina and Antti Herlin foundation [20170005]; Kone Foundation [201710272]; Academy of Finland [332916]

Nigeria is committed to achieving a 20% unconditional and 45% conditional reduction of GHGs emissions by 2030 through a strong focus on awareness and preparedness for climate change impacts via the mobilization of local communities for climate change mitigation actions. As land use and forestry contribute 38% and agriculture contributes 13% of the country’s GHGs, farmers are among the stakeholders to be aware and prepare for climate change mitigations and adaptations. This study assessed the knowledge of agriculturally related practices associated with climate change and its relation to their climate change perception. 1,080 smallholder farmers were interviewed across six agroecological zones of Nigeria using a semi-structured questionnaire. Results of regression models revealed that most farmers know that deforestation and land clearance by bush burning contributes to climate change. However, many farmers did not know that methane emissions from livestock (enteric fermentation) can cause climate change. Our results further show that the farmers’ perception of climate change is associated with climate change knowledge. Factors affecting the climate change knowledge of farmers include information received from government extension services and environmental NGOs, radio, as well as experiencing extreme weather events. Farmers of dry AEZs were more aware and knowledgeable of the agricultural practices contributing to the changing environment. Increased exposure to climate change events thus appears to elevate the knowledge on the topic. Using extension and environmental NGOs and radio to disseminate climate change information will help further in guiding and shaping farmers’ perceptions towards scientific findings for appropriate actions.

The Convention on Biological Diversity and the United Nations Framework Convention on Climate Change are the two most important environmental conventions for biodiversity conservation and climate change mitigation. Both conventions have carried out a variety of work and established a joint working group to promote synergy. This study reviews the cooperation process between both conventions, and identifies the gaps in the synergistic mechanism by analyzing the status of implementation in China. The following problems in China were found to be associated with convention implementation: 1) shortage of coordination among implementing organization; 2) the existing strategic plans lack planning for synergistic implementation; 3) the monitoring system lacks coordination management, thus making the sharing of monitoring results among each unit challenging; and 4) information sharing from partner ministries is inadequate. Combining the status of China’s implementation and the experience of other contracting parties, the following strategies are proposed: 1) a synergistic implementation mechanism should be established at the national level; 2) a national strategic plan should be developed for synergistic implementation; 3) a monitoring system and management mechanism should be developed that comprehensively consider the monitoring indicators of each convention; and 4) an implementation information-sharing platform should be built.

Scope 3 emissions from the UK higher education sector are globally significant, and long-distance air travel and catering are particularly emissions-intensive aspects of workplace routine. They each present complex problems, as transition to low-carbon alternatives requires the reconfiguration of professional practices. This paper examines the sustainability policies of 66 UK universities to establish the extent to which planning and action in these areas are commensurate with climate emergency declarations. The findings indicate that universities recognize their role in creating demand for long-distance travel and sustaining high-carbon diets. However, few have specific emissions reduction targets or action plans that would rapidly and substantially reduce emissions in these areas. Discussion focuses on two core points; first, how greater cohesion in reporting and target-setting can be achieved across the sector to raise the ambition of targets and intervention; and second to identify opportunities for institutions to disrupt and reshape professional practices to reduce emissions in these areas. Key Policy InsightsReducing emissions in the higher education sector requires organizations to foster low-carbon academic practices by engaging with the systemic cultural and material conditions that support high-carbon academic practices.The establishment of robust targets, action plans and monitoring processes would further support sector-wide decarbonization, and require consensus across HE institutions and governing bodies.Sector-wide agreement on the level and pace of emissions reduction will help to accelerate ambition regarding Scope 3 emissions reduction and determining the appropriate contribution of different institutions will help identify where action is most urgently required.Findings suggest a need for absolute targets for emissions reduction associated with long-distance travel, and that food policies focus on achieving a volumetric reduction in the weight of meat served so that absolute levels of greenhouse gas emissions are reduced.Travel and food provision are complex aspects of university emissions, but a climate emergency framing requires all organizations to use their full range of influence to rapidly and substantially reduce emissions. Reducing emissions in the higher education sector requires organizations to foster low-carbon academic practices by engaging with the systemic cultural and material conditions that support high-carbon academic practices. The establishment of robust targets, action plans and monitoring processes would further support sector-wide decarbonization, and require consensus across HE institutions and governing bodies. Sector-wide agreement on the level and pace of emissions reduction will help to accelerate ambition regarding Scope 3 emissions reduction and determining the appropriate contribution of different institutions will help identify where action is most urgently required. Findings suggest a need for absolute targets for emissions reduction associated with long-distance travel, and that food policies focus on achieving a volumetric reduction in the weight of meat served so that absolute levels of greenhouse gas emissions are reduced. Travel and food provision are complex aspects of university emissions, but a climate emergency framing requires all organizations to use their full range of influence to rapidly and substantially reduce emissions.

The objective of the Paris Agreement is to constrain the global temperature increase to well below 2°C and to pursue efforts to limit it to 1.5°C above pre-industrial levels. It is undisputed that ...

Climate change can cause property damage and deaths in cities. City-scale climate projections are essential for making informed decisions towards climate change mitigation and adaptation at city levels. This study aims at developing ensemble projections of temperature extremes at the city-level and quantifying the contributions of various factors to the resulting uncertainty of the ensemble projections. The city of Toronto will be used here as an example to demonstrate the effectiveness of the proposed research framework. In particular, the stepwise cluster analysis (SCA) model will be used to perform climate downscaling to three GCM datasets (GFDL, IPSL, and MPI) under three emission scenarios (RCP2.6, RCP4.5, and RCP8.5) in order to generate city-level climate projections for the city of Toronto. The SCA model is demonstrated to be capable of capturing the inter- and intra-annual variations of the daily maximum, mean, and minimum temperatures in the studied city. The results suggest that mean temperatures in Toronto are projected to increase at the rate of 0.15 and 0.5 °C/decade under RCP4.5 and RCP8.5, respectively, while no significant warming trend is detected for RCP2.6. In terms of temperature extremes, extreme warm events are projected to increase while extreme cold events decrease under all emission scenarios. The decrease in the heating demand is two to four times larger than the increase in the cooling demand, indicating a decrease in the city’s total energy use. The projected warming might be beneficial for the urban growers because of the significant increases in the growing season length and growing degree days; however, the residents of the city of Toronto are likely to experience simultaneous increases in the intensity, duration, and frequency of heatwave events in future summers. Because of the warming, coldwave events in winters are likely to become less frequent and be shorter in duration, but their intensity is expected to increase significantly. Through decomposition of the resulting uncertainty of the ensemble projections, emission scenario is found to be the dominant factor for the uncertainty associated with urban climate projection.

This study aims to propose a framework for assessing climate change in Mediterranean data-sparse contexts. For that purpose, the 309-km2 Lebanese Nahr Ibrahim watershed, extending over 3% of Lebanon’s surface, was chosen as a representative of the targeted settings. Generally, holistic climate change assessments encompass both climate trend analysis and future forecasting. According to the World Meteorological Organization, a continuous, homogenous, and uninterrupted climatic record for at least 30 years is needed to fulfill these tasks. Often, some Mediterranean watersheds lack such data and are hence characterized by climatic data scarcity. Such is the case of Lebanon where 30 years of wars have considerably disrupted the country’s climatic record. In an effort to overcome this state of data scarcity, remote sensing–derived drought indicators were used to determine the climate’s evolution during the last 28 years. For that purpose, several remote sensing indices were extracted from LANDSAT imageries for the period 1990–2018 at a 3-year interval, and were coupled to meteorological indicators. Forecasting was then performed using autoregressive integrated moving average (ARIMA) models. Meteorological indices showed increased variability of precipitations and aridity periods, while remote sensing indicators collectively revealed slight shifts towards increasing droughts. Projections using ARIMA models forecasted increases of 0.9 °C, 0.7 °C, and 0.8 °C for average, maximal, minimal temperatures, and an average 6 mm decrease of precipitations at the 95% confidence level for the year 2030. The presented approach can serve as a tool for proactive climate change mitigation or adaptation plans.

Heatwaves have become more frequent and intense due to anthropogenic global warming and have serious and potentially life-threatening impacts on human health, particularly for people over 65 years old. While a range of studies examine heatwave exposures, few cover the whole globe and very few cover key areas in Africa, South America, and East Asia. By using global gridded climate reanalysis, population, and demographic data, this work analyses trends in change in exposure of vulnerable populations to heatwaves, providing global and per-country aggregate statistics. The difference between the global mean of heatwave indexes and the mean weighted by vulnerable population found that these populations are experiencing up to five times the number of heatwave days relative to the global average. The total exposures, measured in person-days of heatwave, highlight the combined effect of increased heatwaves and aging populations. In China and India, heatwave exposure increased by an average of 508 million person-days per year in the last decade. Mapping of changes per country highlighted significant exposure increases, particularly in the Middle East and in South East Asia. Major disparities were found between the heatwave exposures, country income group, and country health system capacity, thus highlighting the significant inequalities in global warming impacts and response capacities with respect to health across countries. It is therefore of prime importance that health development and response are coordinated with climate change mitigation and adaptation work.

The detection of methane emissions from industrial activities can help enable effective climate change mitigation strategies. These industrial emissions, such as from oil and gas (O&G) extraction and coal mining, typically occur as large plumes of highly concentrated gas. Different satellite missions have recently shown the potential to map such methane plumes from space. In this work, we report on the promising potential of the WorldView-3 (WV-3) satellite mission for methane mapping. This relies on its unique very high spatial resolution (up to 3.7 m) data in the shortwave infrared part of the spectrum, which is complemented by a good spectral sampling of the methane absorption feature at 2300 nm and a high signal to noise ratio. The proposed retrieval methodology is based on the calculation of methane concentration enhancements from pixel-wise estimates of methane transmittance at WV-3 SWIR band 7 (2235–2285 nm), which is positioned at a highly-sensitive methane absorption region. A sensitivity analysis based on end-to-end simulations has helped to understand retrieval errors and detection limits. The results have shown the good performance of WV-3 for methane mapping, especially over bright and homogeneous areas. The potential of WV-3 for methane mapping has been further tested with real data, which has led to the detection of 26 independent point emissions over different methane hotspot regions, such as O&G extraction fields in Algeria and Turkmenistan, and the Shanxi coal mining region in China. In particular, the detection of very small leaks (< 100 kg h−1) from oil pipelines in Turkmenistan shows the unique capability of WV-3 for mapping industrial methane emissions from space. The mission includes pointing capabilities that allow for a daily revisit over these oil pipelines or other critical infrastructure.

The contribution of litterfall (dead leaves, twigs, etc., fallen to the ground) and forest floor (organic residues such as leaves, twigs, etc., in various stages of decomposition, on the top of the mineral soil) is fundamental in both forest ecosystem sustainability and soil greenhouse gases (GHG) exchange system with the atmosphere. The effect of different thinning treatments (control-no thinning, traditional-low thinning, selective-intense thinning) on litterfall and forest floor nutrients, in relation to soil GHG fluxes, is analyzed. After one year of operations, thinning had a significant seasonal effect on both litterfall and forest floor, and on their nutrient concentrations. The intense (selective) thinning significantly affected the total litterfall production and conifer fractions, reducing them by 46% and 48%, respectively, compared with the control (no thinning) sites. In the forest floor, thinning was able to significantly increase the Fe concentration intraditional thinning by 59%, and Zn concentration in the intense thinning by 55% (compared with control). Overall, litterfall acted as a bio-filter of the gasses emitting from the forest floor, acting as a GHG regulator.

The number and coverage of climate change mitigation policies have increased in the past twenty years, but important policy adoption gaps remain. To analyse sectoral climate policy in the G20 over time (2000–2019), we compiled a dataset of climate change mitigation-relevant policies and identified 50 key policy options that constitute a comprehensive sectoral climate policy package. Approximately half of these policy options are not widely adopted. Adoption is particularly low for policies that aim to: phase out coal and oil and mandate energy reductions in electricity and heat supply; reduce industrial process emissions and incentivise fuel switch in industry; design urban planning strategies for retrofits; and support the use of renewable energy for cooking and heating/cooling purposes in buildings. Policies to remove fossil fuel subsidies and support carbon dioxide removal also need substantial improvement. However, many policy adoption gaps exist as the coverage of at least one policy option could be improved in each sector. Policy adoption gaps leave at least one-tenth of the G20’s emissions completely uncovered. Filling these gaps is fundamental to realize the full mitigation potential of existing policy options and to advance the transition towards global net zero greenhouse gas emissions. Key policy insights: Mitigation-related policy options can be presented as a matrix by sector to shed light on what constitutes a comprehensive climate policy package; looking across sectoral climate policies helps to unpack and clarify the status of adoption. Policy adoption gaps exist in all sectors. Increasing the sectoral coverage of climate policies will help to ensure that all relevant sectoral emissions and mitigation areas are considered in national mitigation efforts. Even if an increase in policy coverage alone does not ensure emission reductions, the absence of policy coverage indicates that emissions can still be further reduced and that a portion of global emissions remain uncovered by policies. Despite the observed increase in the number and coverage of climate policies, slow progress towards reducing global emissions and meeting the collective Paris climate goals calls for more comprehensive climate change mitigation policies. Filling policy adoption gaps presents a concrete strategy to improve sectoral, national and global climate policy.

The potential costs of road traffic accidents (RTAs) to society are immense. Yet, no study has attempted to examine the impact of climate change on RTAs in Saudi Arabia, though RTA-leading deaths are very high, and the occurrence of climatic events is very frequent. Therefore, this study aims to assess the impact of climate change on RTAs in Saudi Arabia and to recommend some climate change mitigation and adaptation policies to make roads safe for all. This study employed annual data from 13 regions of Saudi Arabia, from 2003 to 2013. The data were analyzed on the basis of panel regression models&mdash, fixed effect, random effect, and the pooled ordinary least square. The findings show that temperature, rainfall, sandstorms, and number of vehicles were statistically and significantly responsible for RTAs in Saudi Arabia in the study period. This study also found that RTAs both inside and outside cities significantly caused injuries, but only RTAs inside cities significantly caused death. Furthermore, the death from RTAs injuries was found to be statistically significant only for motor vehicle accidents. The findings will assist policymakers in taking the right courses of action to mitigate the negative impacts of climate change through understanding climate influence on RTAs.

Low- and middle-income countries (LMICs) often lack the necessary tools, guidance, and capacity for compiling an emission inventory (EI) for air pollutants. A reliable EI is an important prerequisite for the identification of key emissions sources, as an input to modelling atmospheric transport and impacts of air pollutants, and the identification of appropriate mitigation policies. The publicly-available Global Atmospheric Pollution Forum Emission Inventory (GAPF-EI) tool meets the need of LMICs for a user-friendly tool allowing in-country practitioners to compile their own EIs. The species covered are SO2, NOX, CO, NMVOC, CH4, NH3, PM10, PM 2.5, black carbon, organic carbon and CO2. Output from the tool can therefore support the development of integrated air quality and climate change mitigation strategies. This tool incorporates default emission factors and inventory methods conforming with internationally recognised approaches. The GAPF-EI tool enables emissions to be estimated for technologies or practices that are often of little or no relevance to developed countries, but may represent key sources in LMICs. This paper describes the GAPF-EI tool and its application to Cote d’Ivoire where emissions from traditional biomass cookstoves, vegetation fires, traditional charcoal manufacture, road transport (including dust from unpaved roads) and open burning of municipal solid waste were found to be particularly important components of the inventory. The application of the GAPF-EI approach to Cote d’Ivoire has demonstrated its utility in addressing sources of particular relevance to LMICs in addition to providing a user-friendly, transparent and flexible EI preparation tool.

The present study attempted to investigate the trends of mean annual temperature, precipitation, and streamflow changes to determine their relationships in the upper Huai river basin. The Mann–Kendall (MK), Sen’s slope test estimator, and innovative trend detection (ф) (ITA) methods were used to detect the trends. According to the findings, average annual precipitation shows a descending trend (ф = −0.17) in most stations. An increasing trend was found only in Fuyang station (ф = 1.02). In all stations, the trends of mean annual temperature (ф = 0.36) were abruptly increased. During the past 57 years, the mean air temperature has considerably increased by 12°C/10a. The river streamflow showed a dramatic declining trend in all stations for the duration of the study period (1960–2016) (ф = −4.29). The climate variability in the study region affects the quantity of the streamflow. The river streamflow exhibits decreasing trends from 1965 onwards. The main possible reason for the declining stream flow in the study area is the declining amount of precipitation on some specific months due to the occurrence of climate change. The outcomes of this study could create awareness for the policymakers and members of the scientific community, informing them about the hydroclimatic evolutions across the study basin, and become an inordinate resource for advanced scientific research.

Despite the ocean’s role in regulating the climate and providing ecosystem services, the importance of the ocean has only recently gained appropriate attention in the context of international climate change policies. This concerns the impacts of climate change on ocean ecosystems and the role of the ocean in climate change mitigation. Since impacts can be cumulative, future climate risks for the ocean and dependent human communities emphasize the need to reduce greenhouse gas emissions. Here, we make the case that assessing these impacts and their consequences for human welfare would provide not only an ethical but also an economic justification for strengthening policy responses to a substantial degree.

In the historic year of 2015, 196 Parties came together under the Paris Agreement in a commitment that may well transform their development trajectories, including to limit warming to ‘well below’ ...

Most climate change mitigation policies, including those of higher education institutions, do not include food system greenhouse gas emissions (GHGE). Yet the food system contributes ∼30% of anthro...

A major step towards achieving the goals of the Paris agreement would be a measurable change in the evolution of global warming in response to mitigation of anthropogenic emissions. The inertia and internal variability of the climate system, however, will delay the emergence of a discernible response even to strong, sustained mitigation. Here, we investigate when we could expect a significant change in the evolution of global mean surface temperature after strong mitigation of individual climate forcers. Anthropogenic CO2 has the highest potential for a rapidly measurable influence, combined with long term benefits, but the required mitigation is very strong. Black Carbon (BC) mitigation could be rapidly discernible, but has a low net gain in the longer term. Methane mitigation combines rapid effects on surface temperature with long term effects. For other gases or aerosols, even fully removing anthropogenic emissions is unlikely to have a discernible impact before mid-century., Strong mitigation of anthropogenic emissions is necessary, but it is not clear how fast these efforts would lead to temperature changes. Here, the authors find that there is a substantial delay between reductions of emissions and a detectable change in surface temperature for a number of climate forcers.

From a complexity thinking perspective, the world is understood as complex, systemic, and only partially knowable. The particular perspective we inhabit is determinant of what we can know. Perspect...

Impacts from climate change will significantly affect local governance, and efforts to develop adaptation and mitigation policies will require widespread public support. However, public engagement, and discussions of climate change, remains limited. A new approach to public engagement titled, deliberative framing, can help bridge political divides and provide opportunities to discover innovative policy options. This paper reviews deliberative democracy and framing where they have been applied to examine public engagement on climate change. Integrating insights from these fields can help develop a practice of deliberative framing for managing climate change mitigation and adaptation actions at local scales, to complement national and international efforts. This could assist with community-based agenda setting toward greater justice and the public good. Challenges include building capacity for reflexivity, communication, and public engagement among government actors, recognizing there are different ways to frame climate change and designing deliberative forums that are more inclusive of disparate groups and often underrepresented minorities.

Little has been documented about the benefits and impacts of the recent growth in climate services, despite a growing call to justify their value and stimulate investment. Regional Climate Outlook Forums (RCOFs), an integral part of the public and private enterprise of climate services, have been implemented over the last 20 years with the objectives of producing and disseminating seasonal climate forecasts to inform improved climate risk management and adaptation. In proposing guidance on how to measure the success of RCOFs, we offer three broad evaluative categories that are based on the primary stated goals of the RCOFs: 1) quality of the climate information used and developed at RCOFs; 2) legitimacy of RCOF processes focused on consensus forecasts, broad user engagement, and capacity building; and 3) usability of the climate information produced at RCOFs. Evaluating the quality of information relies largely on quantitative measures and statistical techniques that are standardized and transferrable, but assessing the RCOF processes and perceived usability of RCOF products will necessitate a combination of quantitative and qualitative social science methods that are sensitive to highly variable regional contexts. As RCOFs have taken up different formats and procedures to adapt to diverse institutional and political settings and varied technical and scientific capacities, objective evaluation methods adopted should align with the goals and intent of the evaluation and be performed in a participatory, coproduction manner where producers and users of climate services together design the evaluation metrics and processes. To fully capture the potential benefits of the RCOFs, it may be necessary to adjust or recalibrate the goals of these forums to better fit the evolving landscape of climate services development, needs, and provision.

With the shift of climate debate from understanding to actions, the use of integrated assessment models (IAMs) is gradually expanding. Since IAMs produce least-cost pathways, technoeconomic parameters constitute one of the basic parameters. Traditionally, IAMs dealt with technologies with slowly-changing, relatively homogeneous manner. Since technologies are rapidly evolving, and the pattern of technological development is regionally heterogeneous, the IAM community must embrace a new strategy to treat their underlying technoeconomic parameters. Here we illustrate such challenges by reviewing the treatment and performance of IAMs with respect to some of the rapidly changing technologies (e.g., solar, wind, and batteries). Our review shows that IAMs have difficulty in updating the cost of the rapidly changing technologies. We then articulate a new strategy, drawing upon the lesson from the current model intercomparison projects and climate sciences. We argue that a loose network of modeling groups across the globe should create a database of technological parameters in a standardized format and standard evaluation tool, perhaps to be facilitated by the IAM Consortium. Such a framework would contribute to the review of the progress toward the Paris Agreement goals.

Inquiry into the climate response to external forcing perturbations has been the central interest of climate dynamics. But the understanding of two important aspects of climate change response—nonlinearity and regionality—is still lacking. Here a Green’s function approach is developed to estimate the linear response functions (LRFs) for both the linear and quadratic nonlinear response to ocean thermal forcing in a climate model, whereby the most excitable temperature modes, aka the neutral modes, can be identified for the current Earth climate. The resultant leading mode of the nonlinear response is characterized by a polar-amplified global cooling pattern, unveiling an intrinsic inclination of the modern climate towards cooling. Moreover, optimal forcing patterns are identified to most efficiently excite the corresponding neutral mode patterns. The forcing-response framework developed herein can be utilized to determine the optimal forcing patterns to inform solar geoengineering experiments and to interpret regional climate response and feedback in general.

International climate finance is a sub-set of green finance and refers to investments specifically in climate change mitigation and adaptation activities, which primarily involve public finance and the leveraging of private finance in developing countries. In addition to continued international support for scaling low carbon solutions and facilitating replicability in developing countries, there remains an important need to increase the amount of climate finance provided to innovation, particularly demonstration (for technology innovation) and pilot implementation (for policy innovation), and to channel a greater proportion of Official Development Assistance (ODA) to ‘hard-to-abate’ areas, such as industrial decarbonisation, international transport and cross-sectoral issues like cooling and behavioural insights, to accelerate the commercialisation and implementation of technological, financial and policy solutions to contribute to meeting the Paris Agreement's goal of limiting global warming to ‘well-below’ 2 °C in these countries. Linking research, development and demonstration (RD&D) support with technical assistance is important in providing the route to obtain wider donor finance (concessional finance) and private finance to enable deployment through scalability and replicability.

Purpose of Review South Asia is highly vulnerable to the impacts of climate change, owing to the high dependency on climate-sensitive livelihoods and recurrent extreme events. Consequently, an increasing number of households are adopting labour migration as a livelihood strategy to diversify incomes, spread risks, and meet aspirations. Under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA) initiative, four research consortia have investigated migration patterns and their inherent linkages to adaptation to climate change in climate hotspots. This article synthesizes key findings in regional context of South Asia. Recent Findings The synthesis suggests that in climate-sensitive hotspots, migration is an important livelihood diversification strategy and a response to various risks, including climate change. Typically, one or more household members, often young men, migrated internally or internationally to work in predominantly informal sectors. Remittances helped spatially diversify household income, spread risks, and insure against external stressors. The outcomes of migration are often influenced by who moves, where to, and what capacities they possess. Summary Migration was found to help improve household adaptive capacity, albeit in a limited capacity. Migration was mainly used as a response to risk and uncertainty, but with potential to have positive adaptation co-benefits.

Concern over mitigation costs impedes the adoption of the climate policies needed to achieve agreed global warming targets. While costs are important to consider, so are benefits. However, the evid...

Reconciling climate and socioeconomic goals is a significant challenge in the developing world. Improving living standards is imperative. However, if emerging middle-classes in developing countries mirror current western consumption patterns, the chances of stabilizing greenhouse gas (GHG) emissions at safe atmospheric concentration levels will undoubtedly be reduced. In this sense, the mitigation potential of changing consumption patterns has been increasingly acknowledged. A growing body of literature explores what new consumption patterns might look like, along with their potential contribution to reducing emissions. This paper simulates shifts in household behaviour using a macroeconomic framework. We apply a hybrid computable general equilibrium model with six representative household groups to simulate exploratory scenarios for the Brazilian economy up to 2050. In the reference scenario, household demand is defined by current trends and standards. Consumption patterns converge among income groups, leading to major increases in demand for energy, transportation, consumer goods and services, especially for poorer households. This scenario is contrasted with an alternative pathway in which households seek a less carbon-intensive lifestyle. Our results indicate that a major gap in consumption levels and associated emissions between the poorest and richest households persists in the long run. We also show that sustainable practices contribute to significantly reducing energy-related GHG emissions with minor variations in GDP, employment and income distribution. Key policy insightsThere is a comprehensive portfolio of consumer strategies that can contribute to lowering the GHG emissions intensity of consumption at the household level in Brazil.Through a dematerialized consumption profile, households can contribute to mitigating up to 17% of energy-related GHG emissions compared to a reference projection in 2050.Emissions reduction can be achieved with minor economic losses. Impacts on employment are less than on GDP, since there is a structural shift towards labour-intensive sectors, namely services. However, this comes at the expense of a rise in price levels, given that higher wages lead to an increase in production costs.Per capita emissions from energy use are significantly higher for wealthier households, compared to poorer ones. Therefore, the greatest opportunities for decarbonizing consumption reside in policy interventions that target upper income groups. There is a comprehensive portfolio of consumer strategies that can contribute to lowering the GHG emissions intensity of consumption at the household level in Brazil. Through a dematerialized consumption profile, households can contribute to mitigating up to 17% of energy-related GHG emissions compared to a reference projection in 2050. Emissions reduction can be achieved with minor economic losses. Impacts on employment are less than on GDP, since there is a structural shift towards labour-intensive sectors, namely services. However, this comes at the expense of a rise in price levels, given that higher wages lead to an increase in production costs. Per capita emissions from energy use are significantly higher for wealthier households, compared to poorer ones. Therefore, the greatest opportunities for decarbonizing consumption reside in policy interventions that target upper income groups.

There is growing awareness among governments, businesses, and the general public of risks arising from changes to our climate on time scales from months through to decades. Some climatic changes could be unprecedented in their harmful socioeconomic impacts, while others with adequate forewarning and planning could offer benefits. There is therefore a pressing need for decision-makers, including policy-makers, to have access to and to use high-quality, accessible, relevant, and credible climate information about the past, present, and future to help make better-informed decisions and policies. We refer to the provision and use of such information as climate services. Established programs of research and operational activities are improving observations and climate monitoring, our understanding of climate processes, climate variability and change, and predictions and projections of the future climate. Delivering climate information (including data and knowledge) in a way that is usable and useful for decision-makers has had less attention, and society has yet to optimally benefit from the available information. While weather services routinely help weather-sensitive decision-making, similar services for decisions on longer time scales are less well established. Many organizations are now actively developing climate services, and a growing number of decision-makers are keen to benefit from such services. This article describes progress made over the past decade developing, delivering, and using climate services, in particular from the worldwide effort galvanizing around the Global Framework for Climate Services under the coordination of UN agencies. The article highlights challenges in making further progress and proposes potential new directions to address such challenges.

Carbon capture and storage (CCS) has a fundamental role in achieving the goals of the Paris Agreement to limit anthropogenic warming to 1.5–2 °C. Most ongoing CCS projects inject CO2 into sedimentary basins and require an impermeable cap rock to prevent the CO2 from migrating to the surface. Alternatively, captured carbon can be stored through injection into reactive rocks (such as mafic or ultramafic lithologies), provoking CO2 mineralization and, thereby, permanently fixing carbon with negligible risk of return to the atmosphere. Although in situ mineralization offers a large potential volume for carbon storage in formations such as basalts and peridotites (both onshore and offshore), its large-scale implementation remains little explored beyond laboratory-based and field-based experiments. In this Review, we discuss the potential of mineral carbonation to address the global CCS challenge and contribute to long-term reductions in atmospheric CO2. Emphasis is placed on the advances in making this technology more cost-effective and in exploring the limits and global applicability of CO2 mineralization. Carbon capture and storage has a fundamental role in limiting anthropogenic warming to 1.5–2 °C. This Review discusses the basis, potential and limitations of in situ mineral carbonation as a carbon capture and storage strategy.