Aerosols and their impacts on future Arctic climate change under different emission projections in the GISS-E2.1 Earth system model

<p>In order to study the future aerosol burdens and their radiative and climate impacts over the Arctic (>60 °N), future (2015-2050) simulations have been carried out using the GISS-E2.1 Earth system model. Different future anthrpogenic emission projections have been used from the Eclipse V6b and the Coupled Model Intercomparison Project Phase 6 (CMIP6) databases. Results showed that Arctic BC, OC and SO<sub>4</sub><sup>2-</sup> burdens decrease significantly in all simulations following the emission projections, with the CMIP6 ensemble showing larger reductions in Arctic aerosol burdens compared to the Eclipse ensemble. For the 2030-2050 period, both the Eclipse Current Legislation (CLE) and the Maximum Feasible Reduction (MFR) ensembles simulated an aerosol top of the atmosphere (TOA) forcing of -0.39±0.01 W m<sup>-2</sup>, of which -0.24±0.01 W m<sup>-2</sup> were attributed to the anthropogenic aerosols. The CMIP6 SSP3-7.0 scenario simulated a TOA aerosol forcing of -0.35 W m<sup>-2</sup> for the same period, while SSP1-2.6 and SSP2-4.5 scenarios simulated a slightly more negative TOA forcing (-0.40 W m<sup>-2</sup>), of which the anthropogenic aerosols accounted for -0.26 W m<sup>-2</sup>. The 2030-2050 mean surface air temperatures are projected to increase by 2.1 °C and 2.4 °C compared to the 1990-2010 mean temperature according to the Eclipse CLE and MFR ensembles, respectively, while the CMIP6 simulation calculated an increase of 1.9 °C (SSP1-2.6) to 2.2 °C (SSP3-7.0). Overall, results show that even the scenarios with largest emission reductions lead to similar impact on the future Arctic surface air temperatures compared to scenarios with smaller emission reductions, while scenarios with no or little mitigation leads to much larger sea-ice loss, implying that even though the magnitude of aerosol reductions lead to similar responses in surface air temperatures, high mitigation of aerosols are still necessary to limit sea-ice loss. </p>

The Impact of Demographic Changes on CO2 Emission Profiles: Cases of East Asian Countries

The demographic changes of East Asian countries have accelerated in recent years. With consideration of the linkage between human behavior and carbon emissions, it is necessary to consider demographic characteristics for the CO2 emission projections of these countries. This study examines how changes in the demographic structure affect the emission projections of three East Asian countries (South Korea, China, and Japan) by comparing two different vintages of population projections. The study constructed a dynamic computable general equilibrium (CGE) model and applied the most up-to-date dataset of population prospects, GTAP 10, and the labor force participation rate. By comparing UN2010 and UN2019 projections, the study examined the impact of demographic changes on CO2 emission profiles of the three East Asian countries. The simulation result showed that GDP, which represents economic activity along with the population, is the direct channel of CO2 emission projections. Moreover, the scenario analysis suggested the population factor as one of the main drivers of the CO2 emission projection and a clear positive relationship between GDP and CO2 emissions, though CO2 emissions are generally inelastic in response to a GDP decrease in the three East Asian countries. The finding indirectly implies that not only the size of the population but also demographic composition should be considered to project CO2 emissions, as the labor participation rate is an important factor to determine the production function.

Investigation the effect of sox emission reduction on transit ships emissions as of January 1, 2020

The Istanbul Strait is one of the choke points in the international maritime trade. 44868 ships have passed through the Istanbul Strait in the last two years. These merchant ships are emitting exhaust gas emissions such as CO2, NOx, SOx inten?sively. These pollutants also affect human health and the environment. There is a consensus among scientists that ambient concentrations of particulate matter and SOx have negative health impacts, including asthma, heart attacks, hospital admissions, and premature mortality. In this study, the exhaust gas emissions from ships are estimated based on real ship movements, and analyses are made accord?ing to the reduction from 3.5-0.5% of the allowed sulphur content of the fuel was implemented on January 1, 2020. Firstly, Annex four which is containing the reg?ulations imposed by the International Maritime Organization was examined, and also SOx emission which is caused by ships passing through the Istanbul Strait was investigated. Also, a new approach to Trozzi and Vaccaro methodology was built. After, emission projections for 2030 and 2040 were made and the rate of SOx and particulate matter were analysed.

Investigation the effect of sox emission reduction on transit ships emissions as of January 1, 2020

The Istanbul Strait is one of the choke points in the international maritime trade. 44868 ships have passed through the Istanbul Strait in the last two years. These merchant ships are emitting exhaust gas emissions such as CO2, NOx, SOx inten?sively. These pollutants also affect human health and the environment. There is a consensus among scientists that ambient concentrations of particulate matter and SOx have negative health impacts, including asthma, heart attacks, hospital admissions, and premature mortality. In this study, the exhaust gas emissions from ships are estimated based on real ship movements, and analyses are made accord?ing to the reduction from 3.5-0.5% of the allowed sulphur content of the fuel was implemented on January 1, 2020. Firstly, Annex four which is containing the reg?ulations imposed by the International Maritime Organization was examined, and also SOx emission which is caused by ships passing through the Istanbul Strait was investigated. Also, a new approach to Trozzi and Vaccaro methodology was built. After, emission projections for 2030 and 2040 were made and the rate of SOx and particulate matter were analysed.

Towards the development of a GHG emissions baseline for the Agriculture, Forestry and Other Land Use (AFOLU) sector, South Africa

South Africa is a signatory to the United Nations Framework Convention on Climate Change (UNFCCC) and as such is required to report on Greenhouse gas (GHG) emissions from the Energy, Transport, Waste and the Agriculture, Forestry and Other Land Use (AFOLU) sectors every two years in national inventories. The AFOLU sector is unique in that it comprises both sources and sinks for GHGs. Emissions from the AFOLU sector are estimated to contribute a quarter of the total global greenhouse gas emissions. GHG emissions sources from agriculture include enteric fermentation; manure management; manure deposits on pastures, and soil fertilization. Emissions sources from Forestry and Other Land Use (FOLU) include anthropogenic land use activities such as: management of croplands, forests and grasslands and changes in land use cover (the conversion of one land use to another). South Africa has improved the quantification of AFOLU emissions and the understanding of the dynamic relationship between sinks and sources over the past decade through projects such as the 2010 GHG Inventory, the Mitigation Potential Analysis (MPA), and the National Terrestrial Carbon Sinks Assessment (NTCSA). These projects highlight key mitigation opportunities in South Africa and discuss their potentials. The problem remains that South Africa does not have an emissions baseline for the AFOLU sector against which the mitigation potentials can be measured. The AFOLU sector as a result is often excluded from future emission projections, giving an incomplete picture of South Africa’s mitigation potential. The purpose of this project was to develop a robust GHG emissions baseline for the AFOLU sector which will enable South Africa to project emissions into the future and demonstrate its contribution towards the global goal of reducing emissions.