Search

The European Green Deal (EGD) represents the response of the European Union (EU) to the climate crisis and a strategy to mitigate against climate change and the associated environmental degradation. European Climate Law supports the EGD by setting the legally binding target of climate neutrality for the EU on a time horizon of 2050 and mandates that member states develop and implement their own Climate Action Plans (CAP), which are strategic roadmaps outlining steps to reduce greenhouse gas (GHG) emissions and adapt to the impacts of climate change. Within the Irish context, the CAP focuses on six specific sectors, three of which, namely the energy grid, the built environment and transportation are considered in this research. This policy proposes the retrofitting of all residential buildings in the country to a B2 energy performance certificate (EPC), all public transport and 60% of private vehicles electrified and the full decarbonisation of the electrical grid by 2050. This study aims to implement the targets and goals outlined within CAP 2021 in an urban area of Ireland, specifically a historical city centre. The research leverages digital twin technology developed by IES to model the carbon emissions associated with the built environment, while also incorporating GHG emissions associated with transportation and the grid. Furthermore, CAP scenarios are applied systematically and strategically, prioritising building retrofits based on buildings with similar characteristics, typologies and performance. This study has assessed the performance of CAP about two future grid scenarios (1) business as usual and (2) a decarbonised grid. In both scenarios, CAP was not sufficient to achieve the targets set out, resulting in a shortfall of between 25 and 33%. Based on this outcome it may be concluded that any decarbonisation targets specified should be tested and validated before their implementation in policy. Moreover, current state-of-theart digital twin technologies can facilitate the rapid holistic appraisal of complex multi-sectoral policy at the urban scale, which, depending on data availability, could prove useful in future iterations of CAP at both national and international levels. [ABSTRACT FROM AUTHOR]

Planted forests are in the utilisation phase in Japan, contributing to the increased use of timber and the realisation of carbon neutrality. We simulated and compared the carbon emission reduction effects of three forest management scenarios, including a no final cutting scenario at two geographical scales, in the context of a privately owned Cryptomeria japonica planted forest in Tsuruoka City, Yamagata Prefecture, Japan. We adopted two substitution approaches: the status quo approach and the dynamic approach in line with Japan's nationally determined contribution. We used hypothetical stands over three rotation periods of 150 years at the stand level, and a harvest schedule of 120 years at the regional level. The harvesting scenarios based on the status quo substitution approach reduced carbon emissions more than the no final cutting scenario for current wood usage at the study site, although those based on the dynamic substitution approach reduced carbon emissions as much as the no final cutting scenario during the first 30 years. Sustainable timber production from forests may reduce carbon emissions as much as unharvested forests until 2050, indicating that the substitution effects of harvested wood products could have a significant impact on the climate change mitigation effect arising from timber. [ABSTRACT FROM AUTHOR]

Subnational climate actors are expected to play an increasingly important role in climate actions. However, a trade-off between equity and efficiency emerges when nationally determined contributions (NDCs) are distributed into subnational actions. In this study, we propose a two-staged carbon quota allocation method, with an equity-based 1st-stage allocation mechanism wherein provincial carbon reduction efforts are shared equally and an efficiency-based 2nd-stage allocation mechanism to maximize input–output efficiency. Using China as a case study, we convert China's NDC carbon intensity reduction target into a total emissions cap and apply the allocation method to show that the 2nd-stage allocation significantly increases the total provincial carbon emission efficiency without seriously compromising equity. As the allocation method changes from equity-based to efficiency-based, the carbon quotas mainly flow out from provinces with small emissions and high energy intensity to provinces with large emissions and low energy intensity. The two-staged carbon quota allocation method effectively considers the equity and efficiency principles, which can reduce resistance to the implementation of national NDCs. Generally, the approach has promising application potential for countries to break down the NDC into subnational shares. [ABSTRACT FROM AUTHOR]

Climate change mitigation requires simultaneous reduction of carbon emissions and air pollution. This study examines the synergy between pollution reduction and carbon reduction, identifying key variables and strategies to achieve this goal. Using a Geographical Detector model and a Coupling Degree of Coordination model, 108 cities in the Yangtze River Economic Belt (YREB) are investigated. Results show that while controlling PM2.5 has been more successful than managing carbon emissions in the YREB, synergy between pollution reduction and carbon emissions increased by an average of 7.2% from 2006 to 2019. Spatial analysis reveals higher synergy in upstream areas, indicating significant spatial diversity. The impact of pollution and emission reduction synergies is influenced by societal and environmental variables, including industry structure, technological innovation, energy structure, human capital quality, and economic basis. Synergy is amplified when natural limits align with high-quality development drivers such as technical innovation and the digital economy. Recommendations include enhancing city-to-city contact, improving energy and industrial structures, and fostering technological innovation to address regional variations in synergy levels. • Synergy between pollution and carbon reduction increased by 7.2% from 2006 to 2019. • Higher synergy observed in upstream areas of YREB. • Controlling PM2.5 more successful than managing carbon emissions. • Synergy influenced by industry structure, technological innovation, energy structure, and human capital quality. [ABSTRACT FROM AUTHOR]

Mangrove forests play a crucial role in the coastal environment. A plethora of research is focusing on mangroves' role in climate mitigation through sequestering and storing CO 2. This study aims to assess the organic carbon (OC) stocks and carbon sequestration rate (CSR) of the largest stands of mangroves in the Red Sea Coast of Egypt, to evaluate their significance in climate mitigation strategies. Intensive sampling was conducted in mangrove stands of Safaga, Qulaan, and Hamata to investigate OC and sediment properties along depth intervals to 1 m deep. Additionally, OC stored in the above- and below-ground biomass was estimated using Landsat 9 OLI/TIRS satellite images. TOC content (∼0.50%) and stocks in the sediments (54.49 ± 31.71–86.00 ± 29.00 MgC/ha) were very low compared to the global average for mangrove stands, and comparable to the mangrove forest in the Middle East region. This can be attributed to the desert and semi-desert conditions, limited riverine input, and low precipitation rates. Moreover, the above-ground biomass, estimated from Normalized Difference Vegetation Index, exhibited extremely low OC storage. Therefore, the sediment acted as the main pool of organic carbon in these mangrove ecosystems. The research findings revealed that mangrove stands in Egypt exhibit low CSR, ranging from 11.94 to 18.02 g C m−2 year−1. Additionally, the study determined that the stable nature of mangrove stands in Egypt makes their annual CO 2 emissions negligible. Despite local studies suggesting otherwise, it is highly unlikely that mangroves in Egypt contribute to the climate mitigation related to CO 2 sequestration. Therefore, it is important to implement restoration plans to ensure the preservation of other ecological services provided by mangroves along the Red Sea Coast. • Sediments OC stock ranged from 54.49 ± 31.71 to 86 ± 29 Mg C/ha, in 1m-cores in mangroves of Egypt. • Above- and below-ground carbon stock ranged from 0.08 to 0.45 Mg C/ha as estimated by Landsat 9 OLI/TIRS satellite. • CSR ranged from 11.97 to 18.02 g OC/m2/year. • Mangroves of Egypt showed insignificant contribution to climate mitigation related to CO 2 sequestration. [ABSTRACT FROM AUTHOR]

Planning power system (PS) towards renewable energy is crucial for reducing carbon dioxide (CO 2) emission as well as mitigating climate change. However, the inherent uncertainty and hierarchical structure of PS pose intractable challenges to the planning process. This study develops a multi-GCM-based interval bi-level programming (MIBP) method that can balance two-level decision-making conflict between CO 2 -emisison reduction and system cost minimization. MIBP can also deal with uncertainties expressed as interval values in objective functions and constraints. Then, a MIBP-PS model is formulated to plan PS for China (2021–2050), where the upper-level objective is to minimize CO 2 emission and the lower-level objective is to minimize the system cost. The major findings are: (i) the CO 2 emission for PS would reach peak value before 2030 and then reduce by [10.2, 20.4]% in 2050, which is mainly owing to the curtailment of fossil fuel; (ii) compared with the conventional model, CO 2 emission from MIBP-PS model could decrease by [3.1, 4.8]%, which shows the superiority of the developed model; (iii) the fossil-fuel power would be gradually replaced by renewable energy, and the proportion of coal-fired power would decrease by 38.8% by 2050, especially small coal-fired facilities (i.e., below 0.3 GW) should be gradually phased down. [Display omitted] [ABSTRACT FROM AUTHOR]

The environmental impact of battery electric vehicles (BEVs), which are an integral part of climate change mitigation measures, depends on charging strategies, such as uncontrolled charging, controlled charging (V1G), and discharging (V2G). However, the impact is unclear because power system operation involves the cost of carbon dioxide (CO 2) emissions and flexibility requirements for imbalances caused by renewable energies. To clarify the robustness of the environmental impact of BEVs, we assessed the interactions between CO 2 prices and flexibility requirements in Japan in 2030 using a production cost model. The results showed that uncontrolled charging increases CO 2 emissions, whereas V1G or V2G reduces them. Further, the impact of BEVs was non-monotonic with respect to CO 2 prices, implying that policymakers should carefully evaluate CO 2 prices to achieve decarbonization as BEVs do not always reduce CO 2 emissions. This study provides useful insights for policymakers in countries with low-cost, inflexible, and high-emission power plants. [ABSTRACT FROM AUTHOR]

The Chinese government has announced ambitious carbon reduction goals to address climate change, however, there has been limited scientific attention to the achievement of deep decarbonization in regions with insufficient economic development. Moreover, the complex impacts of climate change mitigation on energy system, environment and economic development remain unclear in Northwest China. Here we construct a comprehensive evaluation model system to evaluate the effects of different climate mitigation pathways in Qinghai, Ningxia, Gansu and Xinjiang provinces. Results show that the four provinces need to vigorously increase the share of electricity that consumed in final energy to 53.1–60.0% and 52.9–62.0% for 2 °C and 1.5 °C target, respectively, and reduce total energy demand to 11.6–44.4 Mtoe and 8.2–34.1 Mtoe in 2050. Meanwhile, the CO 2 emissions for their energy systems will reach peak by 2025 at lower values. Moreover, the synergies of CO 2 reduction are most conducive to abating SO 2 pollution and also contributing to decreasing PM 2.5 concentrations. Additionally, the GDP losses in 2050 fluctuate from 5.0 to 21.7 billion USD in the 2 °C scenario to 11.5–52.7 billion USD in the 1.5 °C scenario. Our study provides practical guidance on achieving carbon reductions in less developed regions of China and lays foundations to promote decarbonization of energy systems in other provinces. • Realizing climate goals requires low-carbon energy systems led by electricity. • Energy-related carbon emissions in Northwest China will peak by 2025. • More ambitious climate and clean air policies are needed for air quality improvement. • Economic loss shows an upward trend in the future under climate targets. [ABSTRACT FROM AUTHOR]