TY - JOUR TI - Has Reducing Ship Emissions Brought Forward Global Warming? AU - Gettelman, A AU - Christensen, M AU - Diamond, M AU - Gryspeerdt, E AU - Manshausen, P AU - Stier, P AU - Watson-Parris, D AU - Yang, M AU - Yoshioka, M AU - Yuan, T T2 - Geophysical Research Letters AB - Ships brighten low marine clouds from emissions of sulfur and aerosols, resulting in visible “ship tracks”. In 2020, new shipping regulations mandated an ∼80% reduction in the allowed fuel sulfur content. Recent observations indicate that visible ship tracks have decreased. Model simulations indicate that since 2020 shipping regulations have induced a net radiative forcing of +0.12 Wm −2 . Analysis of recent temperature anomalies indicates Northern Hemisphere surface temperature anomalies in 2022–2023 are correlated with observed cloud radiative forcing and the cloud radiative forcing is spatially correlated with the simulated radiative forcing from the 2020 shipping emission changes. Shipping emissions changes could be accelerating global warming. To better constrain these estimates, better access to ship position data and understanding of ship aerosol emissions are needed. Understanding the risks and benefits of emissions reductions and the difficultly in robust attribution highlights the large uncertainty in attributing proposed deliberate climate intervention. DA - 2024/08// PY - 2024 PB - American Geophysical Union (AGU) VL - 51.0 IS - 15 SP - e2024GL109077 UR - https://www.sciencedirect.com/science/article/pii/S2589004224001238?via%3Dihub DO - 10.1029/2024gl109077 LA - English KW - Unspecified Feedstock KW - Heavy Fuel Oil (HFO) KW - Unspecified Pathway KW - Lifecycle Assessment (LCA) and Air Emissions KW - Ocean-going Vessels ER -