Carbon emissions reduction potentiality for railroad transportation based on life cycle assessment

This study addresses the comparative carbon emissions of different transportation modes within a unified evaluation framework,focusing on their carbon footprints from inception to disposal.Specifically,the entire life cycle carbon emissions of High-Speed Rail(HSR),battery electric vehicles,conventional internal combustion engine vehicles,battery electric buses,and conventional internal combustion engine buses are analyzed.The life cycle is segmented into vehicle manufacturing,fuel or electricity production,operational,and dismantlingrecycling stages.This analysis is applied to the Beijing-Tianjin intercity transportation system to explore emission reduction strategies.Results indicate that HSR demonstrates significant carbon emission reduction,with an intensity of only 24%-32% compared to private vehicles and 47%-89% compared to buses.Notably,HSR travel for Beijing-Tianjin intercity emits only 24% of private vehicle emissions,demonstrating the emission reduction benefits of transportation structure optimization.Additionally,predictive modeling reveals the potential for carbon emission reduction through energy structure optimization,providing a guideline for the development of effective transportation management systems.

Climate pledges versus commitment: Are policy actions of Middle-East and North African countries consistent with their emissions targets?

Carbon emission is inevitable,and changes with energy consumption and economic development,presents policy options toward sustainable development path.Currently,there is little assurance from policymakers in committing to climate change pledges:taking the Middle-East and North African(MENA)region as a specific case with using 2019 as a cut-off period.We conducted an interim assessment of the Paris Agreement to ascertain whether climate actions are in tandem with emissions reduction targets.Making use of difference-in-difference technique as a quasiexperiment supported by fixed-effects and placebo treatment models,the results point to evidence of less than 1%effective CO_(2) emissions reduction as of 2019 compared to the 2015 level.The current carbon emissions reduction commitment level is far-reaching contrary to the Nationally Determined Contributions(NDCs)pledged(16.43%on average by 2030 compared to the 2015 level).The analysis suggests that achieving NDCs commitments are currently major burden on policymakers since the economic development is highly linked with nonrenewable energy consumption.Furthermore,a more comprehensive framework when accounting for all available renewable and clean energy projects shows reduction levels in the range of 30%-40%from 2020 to 2030.These results suggest that the Paris Agreement in MENA countries may be more effective from 2020,thus underscore the importance of capturing ongoing projects(involving renewable and clean energy technologies)into interim policy assessment.The shared implication is that greater efforts are demanded from the region and at country levels to further decrease emissions through the use of negative emissions technologies particularly in the electricity generation sector.