Barcelona, Cape Town, London and New York are among the few cities that top a list of those taking action on climate change.

Just 7% of 596 cities ranked by CDP, an organisation that helps companies, towns and countries track their environmental impact, scored an 'A' for cutting emissions and setting clear strategy. Some of those, including The Hague, Boston and Sydney, aim to be climate or carbon neutral by 2050, while five have city-wide 100% renewable energy targets – Reykjavik has reached that threshold already.

Image: CDP

“The need for action on climate change has never been more urgent,” said Kyra Appleby, Global Director for Cities, States and Regions at CDP. “We urge cities worldwide to step up their action, set targets in line with what the latest science says is needed to prevent dangerous climate change, and transparently share their progress."

“A” to “D-” grade

More than 625 cities reported information using CDP’s environmental-disclosure platform. Of those, 596 were awarded an “A” to “D-” grade based on how effectively they manage, measure and tackle greenhouse gas emissions and climate-related risks such as water security.

Low-achieving cities aren’t named and shamed, since the scores remain private, and CDP hopes that publicly celebrating those that top the ranks will spur others into action.

To score an “A”, a city should demonstrate strong climate-adaptation strategies and have a clear plan for the future. The 43 top cities have ambitious targets to cut emissions, with 14 aiming to be climate neutral or carbon neutral by 2050. Among these are Melbourne, Reykjavik and The Hague. Melbourne aims to be carbon neutral by 2020, Reykjavik by 2040 and The Hague by 2030, the report said.

London introduced an ultra-low emissions zone this year that will see drivers of older, more polluting cars pay extra to drive in the centre of the city.

Making cities cleaner is vital because of the huge amount of emissions they generate. The World Economic Forum’s Global Future Council on Cities and Urbanization aims to foster smart and sustainable city projects, and these are becoming more important as conurbations grow. The United Nations estimates nearly 70% of the world's population will live in urban areas by 2050, up from around 55% now.

Climate resilience

Calgary has a wide-ranging climate-resilience strategy and is building a new light rail system called the Green Line that aims to cut 30,000 tonnes of carbon dioxide emissions annually. That’s the same as taking more than 23,000 cars off the road a year.

 Calgary has a comprehensive plan to fight climate change.
Calgary has a comprehensive plan to fight climate change.
Image: Calgary Climate Change Program

“Calgary has been a leader on climate action for over a decade now,” said Warren Brooke, Business Strategist at Calgary’s Climate Change Program. “We’ve been at the forefront across the province and the country, piloting strategies to reduce our emissions and increase our resilience.”

The report also singled out The Hague for its new waterfront boulevard that doubles up as protection against coastal flooding, and Taipei for fixing leaks to save thousands of tonnes of water a year.

The latest climate science from the International Panel on Climate Change shows the global economy needs to halve global emissions by 2030 and reach net zero emissions by 2050 to have a good chance of keeping global temperatures within 1.5°C of warming.