Electrified　autonomous　mobility-on-demand　(E-AMoD)　systems　will　play　a　crucial　role　in　future　cities,　which　couple　the　carbon　emissions　generated　by　the　transportation　system　and　the　power　system.　This　paper　proposes　a　joint　dispatching　framework　to　facilitate　city　decarbonization　by　coordinating　the　fleet　operator　and　power　system　operator.　Given　the　substantial　differences　in　spatial　and　temporal　dispatching　scales　between　the　two　systems,　this　framework　effectively　integrates　micro　vehicle-level　service　dispatching　with　macro　fleet-level　charging　scheduling.　Firstly,　a　novel　bipartite　matching　model　efficiently　solves　the　short-term　passenger　serving　and　rebalancing　dispatching　at　the　vehicle　level.　The　service　dispatching　results　are　then　aggregated　as　spatial-temporal　transition　flows　across　different　areas　and　time　intervals.　Incorporating　these　mobility　constraints,　the　long-term　charging-discharging　scheduling　at　the　fleet　level　is　captured　as　an　expanded　network　flow　model　and　integrated　with　the　power　system　dispatching　model,　which　aims　at　renewable　energy　utilization　and　carbon　emission　mitigation.　Finally,　the　fleet-level　scheduling　results　are　disaggregated　to　the　servingrebalancing-charging　sequences　of　each　vehicle,　for　practical　implementation.　To　validate　the　proposed　framework,　numerical　experiments　are　conducted　on　a　large-scale　real-world　case.　Multiple　charging　schedule　scenarios,　including　heuristic　charging,　smart　charging,　and　smart　charging-discharging,　are　investigated　under　both　centralized　and　distributed　supplied　power　systems.　(1)　The　framework　proves　to　be　an　effective　solution　for　addressing　the　differences　in　dispatching　spatiotemporal　scales,　calculation　efficiencies,　and　privacy　concerns　between　power　and　traffic　systems.　(2)　Through　power-traffic　coordination,　the　E-AMoD　fleet　demonstrates　its　ability　to　alleviate　8%　of　average　renewable　energy　curtailment　and　reduce　nearly　15%　of　the　total　emissions　in　a　power　system　installed　with　renewable　distributed　generators.　(3)　Furthermore,　the　extent　of　emission　mitigation　effects　is　influenced　by　critical　factors　such　as　fleet　size,　renewable　energy　profile,　and　power　system　capacity.　Overall,　the　E-AMoD　system　show　great　potential　as　mobile　storage　devices　to　provide　spatial-temporal　flexibility　to　the　power　system　and　contribute　to　city　decarbonization.