Help find solutions to some of the world’s toughest climate challenges

Climate change affects every city on every continent. It's increasingly disrupting economies and affecting human health.Here are some of the toughest challenges cities face today.


Until now, the transport industry has been the most resistant to emissions progress. At the same time, cities are key in tackling this challenge as they are faced with the mobility trilemma of clean air, carbon, and congestion whilst facing ever increasing demands to move people and goods around.


Buildings play a crucial role in mitigating climate change and are directly linked to the resilience of future neighbourhoods, districts, and cities. There is an urgent need for cities to bring about a significant increase in current retrofit rates to realise the "well below two degrees" Paris goal.

Circular economy

Traditional linear economy supports short-sighted design, conspicuous consumption, and inefficient waste handling. Cities are prime candidates for pioneering a new, long-term vision: The circular economy—which integrates sustainable production across supply chains as well as better consumption.


World food production needs to double by 2050 to cater to population growth, while also dealing with the impacts of climate change. The need to develop integrated and sustainable urban food systems, including value chains and consumer behaviour, is an urgent call to action for cities.

Climate finance

In cities, the funding gap for sustainable infrastructure is $93 trillion globally over the next 15 years. Focusing on promising investment vehicles as well as project preparation and capacity building will allow investors to be matched to bankable green assets in cities.

Human behaviour

Citizen behaviour is largely responsible for current trends in global climate change. Hence, changing unsustainable consumption and production patterns unlocks a crucial climate impact potential.

Water management

Cities face increasing water challenges due to climate change. Water utilities, such as drinking water infrastructure, wastewater and drainage can be damaged by storms, sea level rise, and unsustainable policies. Climate change also causes water shortage, affecting over 150 million people globally.


Cities consume 78% of the world’s energy and produce 60% of its emissions. As urban population increases worldwide, cities are crucial to emission reduction efforts.

Extreme weather

In the last decades, extreme climate events, such as heat waves, cold waves, intense storms. and droughts have become more frequent and intense. Further increases are expected to occur at unprecedented levels therefore resilience development is an urgent need for all cities.

Waste management

As cities face pressure to improve resource management efficiency, confront rising energy prices, and are running out of landfill space, reducing or avoiding waste generation becomes increasingly important. Waste management could improve the emissions of all sectors of the economy.

Air pollution

More than 80% of people living in urban areas are exposed to poor air quality. Reducing air pollution should be a priority to all cities, not just for decreasing the negative effects of climate change, but for citizens’ health as well.


For topics that do not fit in any of the other categories

Do you want to organise a Climathon?

We support throughout the Climathon process

We provide you with handbooks, commuication toolkits, branding guidelines, advisory forum and various inspirational content during the Climathon event.

Convince your city!

Show your city you are interested in participating. Either show your interest or send them your proposal directly.

Climathon Stories

Read our Climathon stories to get inspired.


Success Stories

Washington DC, USA

Reducing waste generated when people move from or to residences with a focus on colleges and universities.


Success Stories

Zürich, Switzerland

An app for neighbours to reduce food-waste in Zurich


Success Stories

London, United Kingdom

Internet-of-things (IoT) enabled mobile air pollution sensor, to be mounted on moving agents around the city

This site uses cookies. Read more here. By accepting cookies you can optimise your browsing experience.