Rio de Janeiro, a city of about 6.7 million is also one of more than 70 cities worldwide that are aiming to become “carbon neutral” by 2050, meaning they will produce no more climate-changing emissions than they can offset by other means, such as planting carbon-absorbing trees.
From planting trees to promoting renewable energy and cleaner methods of transport, such as electric cars and buses, each city is going about achieving its carbon neutral goals in different ways, and with varying degrees of success.