The global agreement reached in Paris last December showed ambition to deal with the threat of climate change, but didn’t lock in the specific actions which need to be taken. It can be hard to judge sometimes whether a weak deal is better than no deal at all – the downside is that might start thinking the problem’s been dealt with already.

That seems to be a risk here in Scotland. Monday saw yet another report on the scale of the challenge facing us, with a huge growth in greenhouse gasses in the atmosphere in the last year. After years of weak global deals, we’re still making climate worse at a faster rate than ever.

Yet the SNP chose the day of that report’s publication to launch one of their worst policies for climate change. Like all those global deals, the SNP had the right intentions when they put “world-leading” climate change targets into law. But after four years in a row of missing those targets, it’s clear that the actions have fallen well short of the intentions.

In the wake of those missed targets, scrapping Air Passenger Duty is the last thing we should do.

It’s an imperfect tax, and I would agree that it could be improved. If there is any willingness within the SNP to replace it with something that works better, we could start with the principle that APD should be calculated to ensure that it’s always cheaper to go by train than by plane within mainland UK (or within range of the Eurostar) so that people no longer feel that they simply can’t afford to do the right thing.

The case that APD has “held back growth” is absurd. For a start, it isn’t true. Aviation continues to grow year after year, and APD has not prevented that from happening. But as well as being untrue it misses the point. If we’re remotely serious about cutting our contribution to climate change, we have to face one simple fact – we can’t afford to keep growing aviation like that.

Another launch took place on Monday too – the ‘BusFair’ campaign by the sustainable transport organisation Transform Scotland, making the case for more investment in bus services in Scotland. It might be a less attractive issue for some politicians, who’re more keen on a photo-op at an airport than a bus station. But high quality, affordable and reliable public transport for all of Scotland is surely more important than tax breaks to benefit profitable airlines and wealthy ‘frequent fliers’.

If we want transport policies which benefit the public while protecting the climate, we need a Parliament that’s willing to challenge Government policies which take us in the wrong direction.