The transport industry is still among the most expanding contributors of greenhouse gases in the world with about 23 percent of the total anthropogenic carbon dioxide being emitted by the transport sector with close to 8Gt of CO 2 being emitted each year. The paper will give an extensive discussion of carbon emissions due to transport, modal contribution, and methodology of estimating the emission as well as mitigation methods. As it can be seen, road transport is the leading source of emission, and heavy-duty vehicles make the greatest contribution, despite comprising a small share of the world fleet. More recent innovations in methodology, such as machine learning applications and spatial econometric models have increased the accuracy of emissions estimation and made it possible to implement more specific policy interventions. The paper compares strategies of technological improvement and structural avoid and shift and concludes that the existing complex decarbonisation efforts need to entail vehicle electrification, mode shifting, and demand management as sequential efforts. Results suggest that although electrification has a high potential in emissions reductions, to reach the net-zero transport systems by the middle of the century, combined methods involving technological development and systemic organisational shifts are required.

Increasing temperatures may accelerate crop growth, reduce grain filling, and make crops sterile at sensitive growth phases, threatening crop yields, although higher CO2 has the potential to enhance photosynthesis and water-use efficiency, especially in C3 crops such as rice. Rice (Oryza sativa L.) is a staple grain crop that has a high contribution to food security in the whole world, but also a major contributor of greenhouse gases (GHG), especially methane (CH4) and nitrous oxide (N2O). Factors of climate change, like high carbon dioxide (CO2) levels in the atmosphere and temperature increases, have significant impacts on the physiological activity of rice, the activity of soil microbes, and the cycling of nutrients that, in turn, affect the GHG emission of paddy fields. This review summarizes existing findings on the effect of high CO2 and temperature on CH4 and N2O flux in rice ecosystems individually and in a combined manner. It has been observed that high CO2 increases biomass production, root exudation, and soil microbial activities, thus affecting the generation of methane, but temperature rises promote decomposition of organic matter and conversion of nitrogen to methane and nitrous oxide. The different experimental and field-based studies and simulation models, including Denitrification-Decomposition (DNDC), Daily time-step version of the CENTURY ecosystem model (DAYCENT), and Agricultural Production Systems Simulator (APSIM), that have been employed to forecast the future trends of emissions and the effectiveness of mitigation strategies are also discussed. The results indicate that climate variables and soil processes are highly interconnected, and integrated management practices are necessary to ensure productivity and sustainability of the environment. The review wraps up by determining research gaps, such as the necessity of long-term field tests, further parameterization of the model, and site-specific methods of mitigation that include water and nutrient management. There should be increased long-term monitoring and modeling activities to learn more about the dynamics of emissions, as well as develop policies that will help mitigate the role that agriculture contributes to global warming. Further interdisciplinary studies and mechanisms that involve farmers will be very important in balancing productivity and mitigating the climate.

Rising global electricity demand and the expansion of distribution networks require a critical assessment of component-level greenhouse gas contributions. Distribution transformers, although indispensable, have significant life-cycle carbon impacts due to the use of materials, manufacturing, and in-service losses. This study conducts a life-cycle assessment of a single-phase, 75 kVA oil-immersed distribution transformer manufactured in Newfoundland, one of the provinces with the cleanest, hydro-dominated grids in Canada, and evaluates it over a 40-year lifespan. Using a cradle-to-use boundary, the analysis quantifies embodied emissions from raw material extraction, manufacturing, and transportation, alongside operational emissions derived from empirically measured no-load and load losses. All the data are collected directly during the manufacturing process, ensuring high analytical fidelity. The energy efficiency of the transformer is analyzed in MATLAB version R2023b using measured no-load and load losses to generate efficiency, load characteristics under various operating conditions. Under varying load factor scenarios and based on Newfoundland’s 2025 grid intensity of 18 g CO2e/kWh, the lifetime operational emissions are estimated to range from 0.19 t CO2e under no-load operation to 4.4 t CO2e under full-load conditions. A linear regression-based decarbonization model using Microsoft Excel projects grid intensity to reach net-zero around 2037, two years beyond the provincial target, indicating that post-2037 transformer losses will remain energetically relevant but carbon-neutral. Sensitivity analysis reveals that temporary overloading can substantially elevate lifetime emissions, emphasizing the value of smart-grid-enabled load management and optimal transformer sizing. Comparative assessment with fossil fuel-intensive provinces across Canada demonstrates the dominant influence of grid generation mix on life-cycle emissions. Additionally, refurbishment scenarios indicate up to 50% reduction in cradle-to-gate emissions through material reuse and oil reclamation. The findings establish a scalable framework for integrating grid decarbonization trajectories, life-cycle carbon modelling, and circular-economy strategies into sustainable distribution network planning and transformer asset management.

Greenhouse gas emissions from permafrost peatland of the Daxing'an Mountains under the effects of dry-rewetting conditions.

Abstract The evolution of spectrally resolved outgoing longwave radiation measured at the top of the atmosphere (TOA) reflects the fingerprints of key geophysical variables, serving as a powerful tool for studying climate change. In this work, trends in TOA brightness temperature (BT) in the midinfrared spectral range observed by the Infrared Atmospheric Sounding Interferometer (IASI) are compared with trends in synthetic BTs generated from a set of atmosphere-only simulations with the EC-Earth3 climate model (v3.3.3), over the period 2008–19. Despite the presence of spectral biases, the model simulations effectively reproduce the IASI trends in the thermal infrared. A spectral kernel analysis is then applied to the synthetic radiances to quantify the contributions of temperature, surface temperature, water vapor, clouds, and greenhouse gases to these trends. The negative trend found in the core of the CO 2 band is attributed to the stratospheric cooling, which is overestimated in the climate model simulations. In the wing of the CO 2 band, the negative trend in radiance results from the combined effect of a positive contribution from the increasing tropospheric temperature and a negative contribution driven by rising atmospheric CO 2 concentration. In the atmospheric windows, clouds have a negative impact on the radiance trend and also significantly affect the interannual variability of the model’s radiance. Last, the near-zero trend in the water vapor band reflects a balance between the positive trend driven by temperature increases and the negative trend associated with water vapor changes. This work highlights the utility of spectrally resolved radiances to disentangle forcing and feedback processes, improving climate model evaluation.

The impact of rising CH4 concentrations has become a key global focus in air pollution and climate change, as its photoconversion generates highly reactive methyl radicals with translational potential. However, the overlooked role of •CH3 radicals on HONO formation has led to the underestimated contribution of greenhouse gases on atmospheric oxidative capacity. Here, we propose a CH4-promoted nitrate photolysis route where the nitrate-to-HONO is significantly promoted, varying from 46.98% to 95.75% as the relative humidity increased. In situ spectroscopic and theoretical analyses reveal that the •CH3 radicals activate the NO3- molecule to facilitate N-O bond cleavage and promote H2O dissociation to supply hydrogen atoms for HONO formation, with pivotal •OH radicals from H2O further enhancing this effect under high RH conditions. We also roughly estimated the enhancement of the atmospheric •OH radical budget by CH4 and confirmed its environmental significance through demonstrations on the surfaces of atmospheric fine particulate matter and industrial photoactive materials. This work underscores the interactive relationship between CH4 and atmospheric oxidative capacity and provides direct evidence for the observed enhancement of atmospheric oxidative capacity contributed by greenhouse gases.

Purpose: To quantify the environmental impact of pars plana vitrectomy (PPV), pneumatic retinopexy, and scleral buckle procedures used in rhegmatogenous retinal detachment (RRD) repair. Methods: We conducted a life cycle assessment of PPV, pneumatic retinopexy, and scleral buckle procedures. The primary outcome measure was the greenhouse gas emissions associated with each procedure measured in carbon dioxide equivalents. Results: The total greenhouse gas emissions produced were 51.10 kg carbon dioxide equivalents for PPV, 2.09 kg carbon dioxide equivalents for pneumatic retinopexy, and 12.57 kg carbon dioxide equivalents for scleral buckle. Emissions related to equipment use (30.07 kg carbon dioxide equivalents) followed by equipment manufacturing (21.00 kg carbon dioxide equivalents) were the main contributors of greenhouse gases in PPV. Emissions related to equipment manufacturing (1.60 kg and 8.51 kg of carbon dioxide equivalents for pneumatic retinopexy and scleral buckle, respectively), followed by equipment use (0.49 kg and 4.05 kg of carbon dioxide equivalents for pneumatic retinopexy and scleral buckle, respectively), were the greatest contributors of greenhouse gases in pneumatic retinopexy and scleral buckle. Conclusions: There is a substantial difference in greenhouse gas emissions among PPV, pneumatic retinopexy, and scleral buckle. Quantifying and understanding these differences can inform surgical decision-making.

This study aimed to estimate methane gas emissions from two major solid waste disposal sites in Jalingo, Taraba State, Nigeria, and to assess their potential for energy generation. The research involved determining key parameters of the Landfill Gas Emission Model (LandGEM), specifically the methane generation potential (Lo) and the methane generation rate (k). The methodology encompassed a comprehensive characterization of municipal solid waste (MSW) through compositional and proximate analyses at the Mile-six and Pantinapu dumpsites. The LandGEM software was then applied to project methane emissions, followed by a comparative analysis of greenhouse gas (GHG) contributions from current open dumping practices versus potential energy recovery scenarios, including MSW incineration and methane combustion for electricity generation. The findings indicate that Jalingo's MSW is predominantly composed of plastics (29.67%-34.67%) and agricultural/garden waste (28.00%-29.00%), with food waste constituting a smaller but impactful fraction (5.66%-6.00%). Proximate analysis revealed average moisture contents of 25.40% for Mile-six and 28.98% for Pantinapu, with volatile matter at 38.84% and 37.45%, respectively. The LandGEM model projected peak methane emissions several years into the future, with Mile-six peaking at 7.933×10⁵ m³/year in 2040 and Pantinapu at 5.981×10⁵ m³/year in 2047. The unmitigated release of methane from both sites is estimated to result in a significant total CO2 equivalent emission of 15,577.499 tonnes/year. Significantly, the combustion of generated methane for electricity could achieve an 88.18% reduction in CO2 equivalent emissions compared to current open dumping practices. While MSW incineration yields CO2 emissions of 0.367 kg/kWh, methane combustion for energy generation demonstrates higher carbon efficiency at 0.00291 kg/kWh. This study concludes that energy recovery from solid waste, particularly through methane combustion, offers a viable and highly effective strategy for climate change mitigation and sustainable waste management in Jalingo, thereby contributing to Nigeria's national GHG inventory and fulfilling international climate requirements.

For years, livestock production has been accused of having a supposed impact on global warming. This message permeated broad sectors of public opinion. Recently, questions have arisen about the metrics used to determine the potential contribution of different greenhouse gases. The differences between the atmospheric decays of short- and long-lived climate forcers (SLCFs and LLCFs) and the inadequacy of single-pulse metrics, such as the global warming potential (GWP), to describe sustained emission sources over time, prompted the development of new estimators to compare the warming potential of gases other than CO2. Alternatives such as GWP* show a considerable reduction in the contribution of SLCFs compared to GWP100. This article assesses the differential warming contribution of enteric methane emissions from Uruguayan cattle from 1900 to 2023 using GWP and GWP* and their potential usefulness in negotiating future emission reduction commitments. Data on livestock population and feed were used to calculate annual feed intake and methane emissions. The total cumulative emissions, as calculated using the GWP* method, represented 56% of the CO2-equivalent value estimated using the traditional metric (1,139 versus 2,027 Mt CO2e). Furthermore, the downward trend in annual CO2 warming-equivalent emissions over the past three decades (-60.6%) has been accompanied by a significant reduction in emissions intensity (-13.0%). Considering GWP* as an additional metric can contribute to Uruguay's positioning for future commitments and provide evidence of its compliance.

Linking CO2 and CH4 emissions to the microbial community and land cover in tropical headwater streams of Madagascar.

Abstract This study investigates the impacts of greenhouse gases (GHG) and anthropogenic aerosols (AER) on changes of temperature extremes in Australia during the historical period (1950-2014). Using five large ensembles (LEs) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6), we first analyze long-term changes. As expected, GHG dominate warming but with the signal partially offset by a more subtle AER-induced cooling. However, the AER cooling effect is not evident for cold extremes compared to hot extremes. Based on 40-year running trends, we find that recent decades show faster warming of hot extremes, likely due to a more rapid increase under GHG combined with a decrease under AER. The AER influence is notable for trends centered in the mid-1980s in southern regions. In contrast, the role of GHG in extreme cold remains uncertain due to limited ensemble sizes. A notable AER cooling appears around 1988 in northern regions. In particular, aerosol optical depth, a proxy for AER strength, shows a decline beginning between 2006-2012, which is later than the global trend. Next, an event attribution assessment indicates that the contributions of the two forcings to the risk assessment (as assessed by risk ratio and magnitude shift) are similar to the trends across Australian regions. However, there can be large model differences in risk ratios. Overall, conclusions, particularly regarding AER and the impacts of internal variability, are sometimes less robust due to large inter-model differences and limited ensemble sizes, for which the associated findings should be interpreted with caution.

Abstract Understanding the contributions of anthropogenic climate forcings to heatwave intensification is essential for evaluating mitigation strategies. While greenhouse gas influences on temperature extremes are well established, the impacts of other anthropogenic forcings, particularly aerosols, remain inadequately characterized. Here, we quantify the distinct contributions of greenhouse gases, anthropogenic aerosols, and natural forcings to extreme heatwave metrics from the pre‐industrial period. Globally, changes in the duration of heatwave events and cumulative heat are +2.77 ± 0.85 days and +1.76 ± 0.31°C 2 attributed to greenhouse gases, and −1.10 ± 0.34 days and −0.85 ± 0.14°C 2 due to anthropogenic aerosols, respectively, over the past 3 decades relative to pre‐industrial levels. This indicates that aerosols substantially masked greenhouse gas effects until the 1990s. Under current mitigation policies, declining aerosol emissions have exacerbated heatwave intensification at rates of +1.07 ± 0.32 days decade −1 and +0.47 ± 0.09°C 2 decade −1 for duration and cumulative heat respectively, exceeding the intensification attributable to greenhouse gases alone. Heatwave intensification has been driven primarily by reduced cloud cover and increased shortwave radiation resulting from weakening aerosol forcing, especially in Central North America and Europe. However, the regional climate changes driven by greenhouse gases and aerosols exhibit spatial heterogeneity, highlighting the necessity for geographically targeted mitigation strategies.

Global warming comes from many human activities, such as the burning of fossil fuels and the use of energy can produce Greenhouse Gases. The energy sector itself is the largest contributor of greenhouse gases in the world. This study aims to determine the greenhouse gas emissions produced in the energy sector on Gili Iyang Island. To be able to determine the greenhouse gas emissions produced in the energy sector on Gili Iyang Island, the IPCC 2006 calculation method was used. In this method, primary data is needed in the form of data on energy and fuel consumption activities of residents and secondary data in the form of the number of families on Gili Iyang Island. In the stationary source itself, CO2 gas emissions are produced at 1,438,259.9 Kg/Year, CH4 gas at 324.164 Kg/Year, and N2O gas at 12.486 Kg/Year. Meanwhile, moving sources produce CO2 gas emissions of 510,339.1052 Kg/Year, CH4 gas of 191.363 Kg/Year, and N2O gas of 20.969 Kg/Year. As for mitigation actions that can be taken based on its topography and climate, Gili Iyang Island has the potential to use solar panels and biogas as alternative energy and fuel sources to meet daily needs.

Quantitative estimates of the contributions of anthropogenic impacts (characterized by changes in the radiative forcing of greenhouse gases in the atmosphere) and variations in solar activity to the trends of global surface temperature (GST) on secular temporal horizons are obtained from simulations with climate models of the CMIP6 ensemble in comparison with corresponding estimates based on the analysis of long-term observational data since the 19th century using autoregressive models. The results for simulations with climate models characterized by low, medium, and high temperature sensitivity to changes in CO2 content in the atmosphere are compared. It is found, in particular, that empirical estimates revealing the determinative contribution of the content of greenhouse gases in the atmosphere to the GST trends on half-century and century-long time intervals are most consistent with the estimates from simulations with the INM-CM4-8 climate model of the Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), with the lowest sensitivity of GST to doubling the CO2 content in the atmosphere.

The construction sector is one of the largest greenhouse gas contributors in the world. The use of raw materials as building materials is the main cause of carbon emissions in the construction industry. The use of steel materials has become very popular because it can be associated with a number of qualities, including its extraordinary durability, resistance to pressure, and flexibility. This is the main cause of steel materials being used massively in construction projects. If this continues for a long time, it will result in increasingly severe global warming. Therefore, a very detailed analysis and calculation are needed regarding the relationship between steel weight, carbon content, and structural strength so that, in addition to being structurally strong, it can be efficient in weight and very minimal in the carbon value released during the work process and the life of the building. Tekla Structures software is one of the software programs that can be used for the above analysis needs, the ultimate goal of which is to reduce carbon emissions. Three (3) different cross-section sizes have been examined using structural analysis, and calculations have been made on the carbon content that can be optimized for the material: H 400.400.13.2, 350.350.10.16, and 300.300.10.15. This study has successfully determined that the column with the size H 300.300.10.15 produces a carbon mass of 629,288.00 kg. (kg CO2e). With the smallest carbon content value and the carbon presentation in the material of 66.23%, the column cross-section with the size H 300.300.10.15 is recommended for use as a column structure cross-section

Anthropogenic aerosols are a critical contributor to climate change and their net cooling effects can partially counter the warming effects of greenhouse gases, but they are rarely considered in health impact attribution studies of climate change. The aim of this study was to attribute heat-related deaths in Great Britain to anthropogenic climate change and individual forcings of greenhouse gases and aerosols. Using a special suite of climate simulations, past and future heat-related deaths in Great Britain attributable to the relative contributions of anthropogenic greenhouse gas and aerosol forcings were estimated under the Shared Socioeconomic Pathway SSP2-4.5. Empirical confidence intervals were quantified combining uncertainties from climate models and health risk functions. Emergence of heat-related mortality associated with anthropogenic climate change was partially counteracted by the cooling effects of aerosols, with the time of emergence being approximately four decades later compared with the greenhouse gas-only simulation. We estimate that around 700 annual heat-related deaths during 1961-1980 were masked by the cooling effects of aerosols. There was a sharp increase in heat-deaths between 1980 and 2020 due to the combined effects of greenhouse gas increases and large aerosol reductions. By the end of the 21st century, a 2-6-fold increase in heat-related deaths due to greenhouse gases is projected, with a negligible counteracting contribution of aerosols. In addition to greenhouse gases, the potential contributions of aerosols should be considered when assessing climate change risks and mitigation pathways. This is crucial due to their opposing temperature effects, diverging future emission trajectories, and varying geographical scales. Separate attribution of climate change impacts to the global effects of greenhouse gases and local effects of aerosols can enhance transparency and equity, and can inform loss and damage funding models. Such impact attribution assessments can help to optimise health co-benefits and prevent unintended negative consequences of environmental policies on heat-related and air pollution-related health outcomes. Health Protection Research Unit in Environmental Change and Health, National Institute for Health and Care Research.

The basis for attribution assessments of current extreme weather and climatic events such as droughts and floods is that the record of such events is of sufficient length to be able to compare the occurrence and severity of recent events with those in the past. If this assumption holds, then the magnitude and frequency of extreme hydrological events in the current anthropogenically forced climate can be compared with those in the past under an unforced climate. Attempts to attribute recent floods to anthropogenically-forced climate change have been made, but we argue that such assessments have failed to correctly analyse the true frequency and magnitude of past floods, when anthropogenic Greenhouse Gas (GHG) forcing was low. In this paper we use well-dated, multi-millennial and multi-centennial length records of large floods from multiple sites across Western and Southwestern Europe that demonstrate past floods were occasionally of much higher magnitudes than those of the present-day, and that attribution studies are presently unable to claim that human-created greenhouse gas emissions have increased flood magnitude. We show that flood magnitude was significantly higher before the 20th century, despite there being a negligible greenhouse gas contribution from humans, which means that natural variability might be significantly higher than assumed by climate modellers. This has profound implications for flood planning and climate adaptation policy, as many recent floods cannot be viewed as unprecedented, even in the historical record.

Anthropogenic contributions of greenhouse gases in Earth’s atmosphere have been observed to cause cooling and contraction in the thermosphere, which is projected to continue for many decades. This contraction results in a secular reduction in atmospheric mass density where most satellites operate in low Earth orbit. Decreasing density reduces drag on debris objects and extends their lifetime in orbit, posing a persistent collision hazard to other satellites and risking the cascading generation of more debris. This work uses projected CO2 emissions from the shared socio-economic pathways to investigate the impact of greenhouse gas emissions on the satellite carrying capacity of low Earth orbit. The instantaneous Kessler capacity is introduced to compute the maximum number and optimal distribution of characteristic satellites that keep debris populations in stable equilibrium. Modelled CO2 emissions scenarios from years 2000–2100 indicate a potential 50–66% reduction in satellite carrying capacity between the altitudes of 200 and 1,000 km. Considering the recent, rapid expansion in the number of satellites in low Earth orbit, understanding environmental variability and its impact on sustainable operations is necessary to prevent over-exploitation of the region.

Abstract The attribution of global and regional climate change to anthropogenic greenhouse gases (GHGs) is well appreciated. Existing estimates based on radiative forcing studies suggest carbon dioxide (CO2) has dominated global warming since 1850 with methane (CH4) the second largest contribution. However, radiative forcing studies involve several assumptions and the attribution of GHGs contributions for other climate change indicators is unknown. Here we quantify the impact of individual GHGs on climate change indicators, including regional climate change, in the satellite era using an attribution approach of counterfactual single-forcing CO2, CH4, and other GHGs coupled climate model simulations. CO2 dominates global warming, Arctic Sea ice loss, extreme temperatures and regional warming over North America in the satellite era with CH4 and other GHGs contributing merely around 20% and 30% of the CO2 contribution, respectively. The results demonstrate that, on multi-decadal or longer time scales, CO2 dominates and the contribution of CH4 and other GHGs is small and not distinguishable from noise, especially for regional climate changes. Thus, CH4 mitigation may not be as effective as previously thought, particularly for regional scale impacts.

Greenhouse gas contributions to climate change have driven intense interest in the separation of CO2 from wet flue gas streams. Deep eutectic solvents (DESs) are an emerging class of highly selective CO2 absorbents. A prototypical DES, reline, is a mixture of choline chloride and urea. Reline is a thermally stable, nontoxic, and biodegradable solvent with negligible volatility and is inexpensive. We demonstrate a scalable and energy-efficient hollow fiber membrane contactor (HFMC)-based process using a green solvent for CO2 capture. This process uses reline in HFMC to provide close interfacial interactions and contact between DES and CO2. This approach overcomes the disadvantages associated with direct absorption in DES and could potentially be applied to a variety of solvent-based CO2 capture methods. Commercial, low-cost polymer hollow fiber membranes were evaluated for the capture of CO2 with reline. From a mixed gas containing N2 and CO2, the DES-based HFMC separated CO2 with a purity of 97 mol %. The effect of the viscosity of reline on the CO2 capture performance was investigated by adding water to the reline. The addition of water to reline significantly reduced its viscosity, which led to a permeate flux of 170 mmol/(m2·h) at 35 °C, 4 bar, and 60 wt % water in solvent, which was approximately 8 times higher than that of the pure reline in the membrane contactor system. In situ Fourier transform infrared spectroscopy and nuclear magnetic resonance (NMR) revealed that reline absorbs CO2 by physical absorption without forming new chemical compounds and that CO2 separation by reline occurs via the pressure swing mechanism. This research provides fundamental insights about green physical solvent-based separation processes and a pathway toward industrial deployment.