The　COVID-19　pandemic　and　the　International　Maritime　Organization＇s　(IMO)　2020　fuel-switching　policy　have　profoundly　impacted　global　maritime　activities,　leading　to　unprecedented　changes　in　shipping　emissions.　This　study　aimed　to　examine　the　effects　from　different　scales　and　investigate　the　underlying　drivers.　The　big　data　model　Ship　Emission　Inventory　Model　(SEIM)　was　updated　and　applied　to　analyze　the　spatiotemporal　pattern　of　global　ship　emissions　as　well　as　the　main　contributors　in　2019　and　2020.　Overall,　ships　emitted　NOx,　CO,　HC,　CO2,　and　N2O　declined　by　7.4　%–13.8　%,　while　SO2,　PM2.5,　and　BC　declined　by　40.9　%–81.9　%　in　2020　compared　with　2019.　The　decline　in　CO2　emissions　indicated　a　comparable　reduction　across　vessel　tonnages.　Ship　emissions　occurring　at　cruising　status　accounted　for　over　90　%　of　the　ship＇s　CO2　emission　reduction.　Container　ships,　chemical　tankers,　and　Ro-Ro　vessels　were　the　primary　contributors　to　the　emission　reductions,　with　container　ships　alone　responsible　for　39.4　%　of　the　CO2　decrease.　The　ship＇s　CO2　emissions　variations　revealed　the　decline-rebound　patterns　in　response　to　the　pandemic.　Asian-related　routes　saw　emissions　drop　in　February　2020,　followed　by　a　rebound　in　May,　while　European　and　American　routes　experienced　declines　starting　in　May,　with　a　recovery　in　August.　Further　analysis　of　CO2　emission　in　Exclusive　Economic　Zones　(EEZs)　showed　high　temporal　consistency　between　vessel　CO2　emissions,　sailing　speeds,　and　international　trade　volumes　across　continents,　and　exhibited　heterogeneity　in　main　contributing　ship　type　of　emission　reduction　on　continental　scale.　Our　study　reveals　the　short-term　fluctuation　characteristics　of　global　ship　emissions　during　the　pandemic,　particularly　focusing　on　their　spatiotemporal　evolution　and　the　inherent　disparities.　The　results　highlight　the　correlation　between　global　ship　emissions　and　trade,　as　well　as　the　operational　status　of　ships,　and　their　rigidity.　©　2024　Elsevier　B.V.