I AM in Paris for the COP21 climate change summit. Paris feels subdued in the wake of the Daesh shootings. There are burly French police everywhere, ostentatiously exuding a “get tough” policy. My train from London was uncharacteristically quiet, with plenty of empty seats. Fortunately, attendance at the climate summit does not seem to have been affected, though the jittery French authorities have put a number of local green activists under house arrest and banned demonstrations at COP21 – a classic over-reaction.

Taking the RER train through the sprawling suburbs of north Paris to the conference venue at Le Bourget is a good education in why a lot of the immigrant Muslim community in France feel disaffected. One passes through miles of soulless high-rise blocks, burned-out shells of cars, festering mounds of household and industrial refuse, and wall-to-wall graffiti. These are the banlieue housing estates where immigrants from France’s former colonies congregate, and where youth unemployment is massive. This is land that the self-satisfied French political system has forgotten.

Mind you, the French are good at orchestrating big international jamborees like COP21, the latest in a line of UN summits which have sought to broker global agreement to reduce greenhouse gas emissions. Sadly, if predictably, these summits have produced meagre results. At the time of the first UN climate change conference back in 1995, the atmospheric concentration of carbon dioxide was 361 parts per million. Today it is pushing 400 parts per million. Climate change deniers can huff and puff, but the wayward energy thus trapped is on course to wreck our biosphere, disrupt the economy and initiate mass migration.

Not that I’m against trying to create an international framework to reduce greenhouse emissions and mitigate their social and physical impact. That’s why I’m here at COP21, along with 195 world leaders and a good 40,000 participants from NGOs, banks, big corporations, churches, community groups, animal rights organisations, local authorities and human rights bodies, not to mention a bevy of ‘concerned’ rock stars. At stake is the possibility of reaching a legally binding agreement aimed at holding the rise in global warming to 2°C above the pre-industrial level. Beyond the 2°C benchmark, life as we know it comes under serious threat.

If COP21 achieves nothing more, it marks a clear acceptance by the bulk of the international community that global warming is a reality. What ambiguities in the scientific analysis existed, say, 15 years ago have long been dispelled. A seeming hiatus in the global temperature rise between 1998 and 2012 gave deniers such as former UK chancellor of the Exchequer Nigel Lawson a chance to pontificate. But we now have a better understanding of the various feedback loops involved in the propagation of the energy flows from the trapped greenhouse gases. What seems to be missing there is popping up over here. A lot of the trapped heat energy has been absorbed (temporarily) in the oceans from where it is about to escape with a global vengeance – taking us beyond the 2°C red line perhaps as early as 2050.

The change in perceptions – if not action – is clear at COP21. I attended a session organised by a group of young Chinese students, mostly female. Their English was flawless, their charm engaging, and their passion for tackling climate change manifest. And not an official “minder” in sight. They came from universities across China, where they had set up their own campaign to force their campus authorities to do something practical about reducing energy consumption. For instance, turning off most of the campus lights during the night – something I might recommend to Scottish universities.

The point here is that contemporary Chinese young folk – that nation’s future managers, engineers, lawyers, bankers and party activists – have embraced the need to tackle climate change. Their biggest passion seemed to be the need to invest more in solar energy forms. China is, of course, currently the world’s biggest polluter. No global deal to cut emissions can work without Chinese consent. But a corner has clearly be turned as China’s educated and aspirational middle class decides it wants to breathe cleaner air. A third of the money now invested internationally in renewables is being spent in China. The dirtiest of China’s coal-fired power stations are being shut down. True, there is a heavy commitment to nuclear, and we will be getting Chinese atomic power stations in the UK if George Osborne has his way. But it is no longer the case that China can be used as an excuse for the West – particularly the UK and US – reneging on its commitment to curb its own emissions.

YET renege is precisely what the UK Tory government is doing. Amber Rudd, Britain’s Climate Change Secretary, is due in Paris this week. She is in for a frosty reception as word of the UK’s retreat on combatting climate change spreads through the summit. I confess to having done my bit to let foreign NGOs and delegations know about Chancellor Osborne’s scrapping of the £1 billion Peterhead Carbon Capture and Storage project, barely weeks before it was due to get the go-ahead. And the Treasury’s plan to sell off the Green Investment Bank. And the slashing of the feed-in tariff that encourages investment in renewables, especially solar power. American attendees at COP21 are especially mystified by the UK Government’s negative attitude to solar power.

Contrast this with the positive reception attendees from Scotland have been receiving at COP21. Quite a number of international representatives volunteered to me how impressed they were that the key Scottish speakers – the First Minister and the Holyrood climate change minister, Aileen McLeod – were both women. Of the 150 heads of state and government attending COP21, the overwhelming majority were men in suits. Aileen McLeod exuded a passion and knowledge regarding climate action that was in marked contrast to the tired, formulaic stuff I heard from other visiting politicians.

What is driving the Tories to dump policies designed to promote renewables and switch emphasis towards fracking for gas? At Westminster, their daily refrain is that we now have “enough” renewables and so can end subsidies as a way of reducing costs to business and the consumer. These claims are self-serving nonsense. Osborne did not cut the carbon levy on burning fossil fuels – he has actually imposed it on the renewables industry, as a fundraising measure in pursuit of his daft notion of running a permanent budget surplus. The drive towards fracking is yet another Treasury tax-harvesting scheme.

Will COP21 make a manifest difference? My worry is that there are too many people here in Paris who are already convinced of the need for action; it’s the converted speaking to each other. And while the world’s leaders are turning up to be photographed, there is unlikely to be the concerted action needed to meet the 2°C target.

Worse, there are new problems to be factored in: we are likely to see 200 million climate change refugees heading from the south to the north of the planet by 2050. Still, COP21 seems to have re-energised grassroots climate change activists and put world leaders on the spot. As ever, change is coming from the bottom up.

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