Black carbon emissions in Jordan: national inventory, climate and health implications (2022-2050)

Black carbon (BC), a short-lived climate pollutant with a global warming potential hundreds of times greater than CO₂, remains largely excluded from international climate frameworks and is absent from Jordan's national emission inventories. This study develops the first nationally validated BC inventory for Jordan, projects emissions to 2050, and evaluates associated health and climate impacts alongside mitigation potential using the Low Emissions Analysis Platform-Integrated Benefits Calculator (LEAP-IBC). Emission factors were locally validated through literature review and consultation with more than 40 national experts, replacing generic global defaults. The results estimate Jordan's 2022 BC emissions at 6,977 tonnes (95% CI: 2,582-7,460 tonnes), with the transport sector contributing 59% ± 8% and the energy sector accounting for the remainder, both dominated by diesel combustion. Comparison with global datasets shows systematic underestimation of national emissions by factors of 2.8-4.5, consistent with findings for other countries. BC climate impacts are found to vary substantially with the choice of GWP metric: 2022 emissions are estimated at 2,480-23,004 GgCO₂-eq, with GWP₍₂₀₎ assumptions (1,200-3,200) producing higher estimates than GWP₍₁₀₀₎ assumptions (345-900).. By 2050, BC climate impacts are projected at 6,034-55,970 GgCO₂-eq, with GWP₍₁₀₀₎ yielding lower values (6,034-15,742 GgCO₂-eq) than GWP₍₂₀₎ as its impact is diluted when averaged over 100 years. Model projections suggest that BC's share of PM_2.5 exposure will nearly double from 1.7% to 3.3% by 2050, with more than 90% of the associated health burden linked to cardiovascular diseases in an aging population. Coordinated mitigation across the transport and energy sectors could reduce BC emissions by up to 53% relative to baseline scenario, with priority strategies including Euro VI vehicle standards, public transport electrification, industrial efficiency improvements, and accelerated renewable energy deployment.