We can't get complacent about the threat of climate change, but it's also important to celebrate progress when we can: like the news that more than 6,000 cities are currently ahead of the 20 percent minimum cut in carbon emissions being targeted by the global community.
Those cities – which include London, Paris, and Berlin, along with thousands of others – are part of the Covenant of Mayors (CoM). The CoM is a voluntary group of regional leaders committed to a 27 percent emission reduction by 2020 compared to levels from 1990 – an extra 7 percent reduction above the global 20 percent agreement.
And the group's latest report shows they're on target to hit it, with a 23 percent reduction so far overall. The building sector has seen the biggest drop, already cutting emissions by 27 percent with more than three years to spare.
Considering half of the world's population lives in cities, and they produce around 75 percent of global CO2 emissions, that's encouraging news – but there's still a lot of work to do, with a 40 percent reduction target pencilled in for 2030.
"When we look at the impact of city climate action around the world, we can only draw one conclusion: cities are crucial partners in the world's fight against climate change," explains the Vice President of the European Commission, Maroš Šefčovič.
As well as working towards its carbon emission targets, CoM members are also dedicated to adapting cities to cope with climate change, and finding alternative energy sources that are "secure, sustainable and affordable".
Other policies mentioned by the report include raising awareness of climate change issues, getting new buildings to meet agreed environmental standards, and offering rewards for eco-friendly living (like priority parking for low-emission vehicles).
To date, the cities that have signed up to the CoM account for nearly 223 million people, or about 3 percent of the world's population, which isn't a bad start – and they've all committed to regular monitoring and assessments to stay accountable.
Plus, if each CoM city can achieve its goals, that will account for 31 percent of the total greenhouse gas emission reductions that the European Union needs to hit its 2020 targets.
"While the steps we take in local communities around the world are vital to the future of our cities, they are also vital to the future of our planet," says the President of United Cities and Local Governments Mpho Parks Tau.
"Cities are stronger when we work together... we call on the international community to support our efforts and recognised them as official contributions to reaching the Paris Agreement."
Next year the mainly European Covenant of Mayors (which now boasts 7,120 signatory cities) is joining forces with the global Compact of Mayors – a group representing fewer cities but focused on larger metropolises.
The ultimate aim is form a climate change supergroup, to concentrate the environmental efforts of cities and local governments.
Let's hope there's a lot more positive news to come.