Something wonderful is uniting cities across the globe: Bristol, London, Vancouver, Oakland and Berkeley in California, as well as a plucky Yorkshire local authority, Kirklees, to name but a few. All have recently declared a climate emergency or are actively planning to.

It’s a movement aiming to make the world a safer place. As so often in human affairs some people get there before others. But it’s not too late for York to join the party.

So what does it mean to declare a climate emergency? First off, it involves whole communities no longer sticking their collective head in the sand when it comes to the scary reality of climate change.

Take the news from Greenland only last week: just one example from hundreds of similar stories. Greenland’s ice is melting far faster than scientists previously thought, with the pace of ice loss increasing fourfold since 2003, new research from Ohio State University has found.

As global temperatures rise, enormous glaciers are depositing ever larger chunks of ice into the Atlantic, where it melts causing gushing rivers of meltwater to flow into the ocean and push up sea levels. Michael Bevis, lead author of the paper and a professor of geodynamics, said: “We’re going to see faster and faster sea level rise for the foreseeable future. Once you hit that tipping point, the only question is: how severe does it get?”

The study points out vulnerable coastal areas as far apart as as Miami, Shanghai, Bangladesh and various Pacific islands are in danger of catastrophic flooding over coming decades. The political, ecological and humanitarian effect would be incalculable: famine, refugee crises, economic dislocation, species extinction, you name it. This stuff matters.

Thank goodness some local politicians across the world have the vision and courage to remember that a stitch in time saves nine.

So what does a city declaring a climate emergency involve? First off, publicising the decision to every citizen, explaining the gravity of the crisis we face. That’s the easy bit. Then comes the slow, patient work of commissioning a comprehensive audit of the council’s carbon footprint, identifying hotspots and working toward being carbon neutral in line with targets set and agreed by the United Nations Intergovernmental Panel on Climate Change. This work must result in practical measures to reduce emissions and a council’s carbon footprint, not just reports.

After that, local politicians have to get passionate and serious on the issue in the community, actively implementing changes that are potentially unpopular with some voters and local businesses concerned with the bottom line. A good example might be whether York should drop plans to dual the ring road. After all, most pieces of serious research on road building since the 1920s confirm bigger roads just create bigger pollution and ultimately increased car use. Instead, politicians have to create affordable, reliable and frequent public transport, preferably co-ordinating rail, bus and even new tram services.

Another change might include really tackling the issue of recycling in York. At present, far too few types of plastic are recycled compared to other local authorities. And what about organic waste, something other councils manage to recycle? A council that has declared a climate emergency will deal with those issues as a priority.

It would also encourage action in the wider community, businesses and other key organisations, such as the NHS and local educational institutions. Likewise, collaborating with other local and regional authorities on emission reduction projects is crucial, as well as urging the government to develop national policies that reflect the seriousness of the current emergency. Lastly, they would lobby central government to release funds to local authorities to tackle this issue.

Ordinary people need to tell our politicians from all parties we are out of time to act. Locally and as a nation we are either part of the problem or part of the solution. Changing our priorities in order to live more sustainably is, I believe, both basic self-interest and a moral imperative. Surely it is time for York to join other cities across the globe by declaring a climate emergency.