Rome is limiting auto circulation, and other Italian cities are offering free bus rides to encourage public transport use as the country battles seasonal air pollution that has been worsened this year by long spells of no rain and little wind.

As it has done several times this fall, Rome this week limited the number of cars and motorcycles on its roads using a system based on license plates. Vehicles with plates ending in an odd number were banned Monday and vehicles with plates ending in an even number were prohibited Tuesday.

In northern Turin, public transport was free for two days this month to try to entice commuters away from cars. Milan recently put some limits on older cars.

Little relief is in sight, with more rainless days predicted.