HOW do you even begin to visualise what 700,000 young people might look like? It’s a huge number, greater than the entire population of Edinburgh or Glasgow, and enough to fill the national stadium at Hampden a dozen times over.

Yet that’s how many young people have signed up for free bus travel in Scotland. Between them, they have taken more than 100 million free journeys – a major milestone that covers the length and breadth of our country.

I’ve been a member of the Scottish Parliament for 20 years, and this is one of the single biggest and most important changes in that time.

When we originally introduced the scheme two years ago, we were met by naysayers asking if it would be popular or successful, but 100m free journeys is the perfect response to that.

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It is why I was delighted to spend yesterday morning in the company of a group of school students in Wester Hailes in Edinburgh, along with the Transport Minister Fiona Hyslop, as they told us about the impact that free bus travel is having for them.

For some, it means they have more opportunity to explore their city. For others, it means they are able to see friends and family who they otherwise could not afford to see. I’ve spoken to young people around the country who have told me how free bus travel has allowed them to take jobs or college courses that they otherwise couldn’t.

It’s the sort of change that can be transformational both for young people themselves and our society.

Accounting for more than a quarter of all our emissions, decarbonising transport is one of the most important steps we can take if we are to reach our climate targets. Public transport has to be at the heart of that change.

I believe Scotland can build on this success and have high-quality affordable public transport for all. I want us to be a country where nobody feels that they are forced to drive because it is their only option.

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Yet, knowing what it’s like to wait in the cold and wet for the next bus, I understand that free buses requires buses for people to catch. It’s no secret that some parts of our country have far better bus links than others.

One of our biggest challenges has to be to harness the technology that is now available to make buses a viable choice in all parts of Scotland. That has to be backed up with funding, with a community bus fund that is supporting councils to make the changes.

It’s a key step towards an integrated and low-carbon transport system. But it is only one part of the jigsaw, alongside greener railways and investment in walking, wheeling and cycling infrastructure.

By improving transport, we can rebuild our communities as cleaner and happier places that everyone can freely and easily navigate. It means safer, less congested streets and less pollution.

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It’s reflective of the response that all governments must be taking to the climate crisis. Bold, clear and inclusive action that boosts public transport, helps people to make positive choices and doesn’t cost the earth.

It is hugely disappointing that, despite the success we have seen in Scotland, no other part of the UK has followed in our footsteps.

It is the sort of creative, cost-saving and emission-reducing solution that will offer help and support to families, particularly in a cost crisis, while changing habits and leaving a positive legacy.

Changes like this are more necessary than ever. The sustainability of our climate is being held together by the thinnest of threads, with each news story on climate trends being more daunting than the one before.

Scotland doesn’t exist in a vacuum, and there are countries around the world that are feeling far greater impacts. Getting our house in order isn’t just about protecting ourselves, it is also a basic act of solidarity with them.

The National: Energy minister Graham Stuart said the Cop28 deal is ‘not perfect’ but is a ‘turning point’ (Andrew Milligan/PA)

It’s a sign of how desperate things have become when one of the main successes of the COP28 climate summit was that our leaders finally acknowledged the need to transition away from fossil fuels.

It was an agreement that was made through gritted teeth and was a backward step from the language of a “phase out” that’s urgently needed, but it at least gives a clear direction of travel.

There were other welcome steps, but, on the whole, it will go down as another missed opportunity. We can’t keep getting leaders and the best climate scientists in the room together to negotiate packages that would have felt unambitious 10 years ago let alone right now.

We need to go further and faster if we are to secure a national, global and genuine transition that leaves no worker or community behind.

Scotland has a particularly important role to play. As an oil and gas rich nation, we must come to terms with leaving the stuff in the ground. We are also blessed with natural resources that can fuel our transition and help us to break away from decades of fossil fuel reliance.

The biggest changes have to come from governments and corporations, no question of it. But we all have a part to play.

Every time we choose to get on a bus or a train or cycle rather than driving, we are helping to build that better future. In Wester Hailes yesterday, it was refreshing to hear how eager so many are to join us on that journey.