YOU could hear them before you could see them. The chanting of an estimated 10,000 children, young people, parents, grandparents and adults of all walks of life­ – all calling for climate justice – echoed through Glasgow’s city streets on Friday.

Climate strikers, both young and old – teenagers in school uniform with a banner that read: “We’re bunking school to educate adults”, parents pushing tiny children in brightly decorated buggies, and groups of workers – wound their way from Kelvingrove Park, though Charing Cross and emerged onto Sauchiehall Street in the sunshine.

Most held aloft a homemade placard. “The seas are rising and so are we”, read several and the slogan seemed to capture the mood. This Glasgow protest, organised by the Scottish Youth Climate Strike, was one drop in an oceanic worldwide rallying call that saw millions spill onto the streets to demand urgent action to lower carbon emissions and halt dangerous level of global warming.

Organisers, who also held an even bigger march of about 15,000 in Edinburgh, included the young guest editors of last week’s special edition of the Sunday National. Scotland’s Children and Young People’s Commissioner wrote to local authorities asking the to respect young people missing school, while businesses, doctors and academics came out in support.

The protests aimed to send a crystal-clear message to those attending the Climate Action Summit in New York tomorrow about the need for countries across the world to take concrete steps.

I was there with my own two primary school-aged children – grappling with the simultaneous roles of parent, striker and journalist, and like many, squeezing in time for the march in with other commitments.

Me and mine pushed our bikes up the hill as the protest reached Glasgow School of Art, where hundreds of students had walked out in support. Drummers from SheBoom paused, and dropped the volume of a drum roll, building back-up to a crescendo that had crowds whopping in delight.

And then we were back on the move, winding our way through the city centre, attracting workers out to watch on their lunch breaks. One later said it would have been impossible to work through the noise even it they’d wanted to.

To my children, who had attended several much less well-attended climate strikes previously, these numbers were impressive – a wall of people and noise that stretched right up the street. It took about 30 minutes to pass a single spot.

For the adults attending there were professional and personal interests at stake here. Doctors told me about their duty to raise concerns about the global health disaster approaching, teachers about our need to educate, while I was all too aware of the need for journalists to report the truth on global warming.

Like many parents my reasons for supporting are also about fears for the future my children and the rest of their generation. What ecological difficulties will they be forced to grapple with if unless we can start seriously reducing our fossil fuel use and investing in restoring our natural habitats?

Countries around the world have already start to experience the effects – which impact the world’s most marginalised disproportionately – with droughts and flooding, and millions displaced.

Greenland’s ice sheet is disappearing far faster than scientists predicted and the IPPC warned last year that the world must keep temperatures from rising more than 1.5C to avoid ecological melt down.

Facing such stark predictions, the carnival atmosphere of Friday’s march, which finally reached a packed George Square full of music and colour, could seem incongruous.

And the doubters might point out that marches don’t really achieve very much. But some told me that it was important it was fun – if you love the world and the people in it you’re more likely to work to save it.

Others said it simply felt necessary to protest together alongside others. Kate Langhorn, 29, who has just completed a masters at Glasgow University came with her mother because she wanted to get more involved. “It might be too late to meet the targets so it doesn’t feel empowering any more to be on social media, liking and sharing,” she said.

“I’m still discovering what ‘activist me’ might be but it’s something I’m now seriously thinking about.”

For Teresa McNally, 75, who got the train from Alloa to support, it was about turning the feeling of fear into hope that it’s not too late to implement change. “I’ve never got involved with these strikes before and it’s an amazing turn-out,” she added.

“We’re just standing here watching all these young people from different schools going past and it’s great to see. We’ve got to be hopeful that change is possible. That’s what this is for me.”

In the square Glasgow University psychology students Genevieve Warrender, 22, Mathilde Sijtsma, 21, and Leonie Schorrlett, 22 explained this helped to energise their commitment to environmental issues.

“It’s so positive to see tiny children with their parents, and all sorts of people, not just students – to see that everybody feels the same about it,” explained Sijtsma. “It feels like there is a real sense of unity.

“Seeing how many people out here inspires you to be more active. And if you are active, that gets amplified by the march.

Warrender raised an eyebrow: “I think a lot of people here are already quite active. But the point is to inspire the government, right? “Yes, but I think it’s also about inspiring you to be a bit louder about everything,” said Schorrlett. “If you can be loud in this crowd, you can be loud when you go back home too.”

Making a noise might never have been so important before. The hope is these young people are not only being seen and heard – but heeded as well.