cars stuck in gridlock emit smoky exhaust fumes amidst urban pollution concerns

traffic congestion bumpertobumper urban environment exhaust emissions air pollution concerns fossil fuel dependence vehicle fumes transportation infrastructure mitigation strategies city gridlock environmental impact greenhouse gas sustainable solutions clean initiatives reduced quality smoggy conditions automotive sprawl airborne pollutants flow optimization public transit alternatives walkability improvements carpooling incentives idling roadway capacity emission standards climate change ecofriendly options transitoriented development planning