Nahlah Ayed reports from Le Bourget, France
Among the flimsy particleboard walls and too-bright walkways at one of the climate-change exhibitions here in Le Bourget, an old hand like Al Gore seems right at home.
The former vice-president of the U.S. and longtime environmentalist seems equally unbothered by the many admirers crowding him in pursuit of handshakes and selfies, which he gives out freely.
Being in the fray at the largest ever single-day gathering of world leaders surely must make him feel optimistic, I asked.
"Yes, I am," he said with a smile, before being ensnared in yet another selfie.
For veterans of these kinds of gatherings, this optimism at COP21, the international climate change conference just outside Paris, couldn't be less familiar.
It is even starker for the Canadian environmentalists here who have long awaited a bigger role for Canada in trying to hammer out a global deal.
That's not to say the familiar hand-wringing over the prospects of an emissions reduction deal on which more than 190 countries can agree is absent.
The reminders of the damage being done by global warming are constant. The latest ominous headline, just today: "Nine of the hottest 10 years on record have happened since 2000."
And the hints at possible disagreement also started shortly after a record 147 world leaders were ushered together under one roof.
The summit isn't "a turning point" but "a starting point," Chinese President Xi Jinping said, correcting U.S. President Barack Obama's early enthusiasm.
India's Narendra Modi also insisted that developing countries like his cannot stop using conventional, greenhouse gas-producing energy sources cold, without suffering economic consequences.
'It's a rush'
Still, as the hard negotiating at this 12-day conference gears up, the optimism is hard to miss — especially when it comes from some of the world's most hardened environmental groups.
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"I wouldn't want to give you a suggestion that there are no major challenges here, because there are some really big hurdles to overcome in the next couple of weeks," says Ruth Davis, of Greenpeace U.K.
And yet, "I feel cautiously optimistic that we're going to get a better result than we did" back in 2009 at Copenhagen, the last serious shot at a global deal.
The summit at Copenhagen was a benchmark low that many of those who've been around the climate change block often use for comparison.
Vancouver Mayor Gregor Robertson has attended both summits and says the difference in mood this time is obvious.
"There is still real concern out there. There needs to be. This stuff can slide backwards fast," he says.
But "all of a sudden it feels like in this last year we've had a breakthrough and we hit the tipping point, and now there's so many people coming to the table.
"It's a rush to feel this kind of momentum to it now."
Sense world is watching
Part of the excitement is the mere presence of all those world leaders right at the start of the summit, saying (almost) all the right things.
It is clear, from everything these leaders have said so far that they know many in the world are watching.
Another part is the number of initiatives — and dollars — being devoted here to the development of clean and renewable energy.
"I actually think we're going to do it. I actually think we're going to solve this thing," said an upbeat Obama.
"If you had said to people as recently as two year ago that we would have 180 countries showing up in Paris with pretty ambitious targets for carbon reduction most people would have said you're crazy. That's a pipe dream.
"And yet here we are."
The tone set by the leaders was applauded by the Climate Action Network, an international group of more than 900 organizations working on climate change.
Few things are as familiar at these talks — aside perhaps from the fear of failure and the immense security — as the daily Fossil Awards handed out by that Climate Action Network.
It's been done at every summit since 1999 to recognize countries that appear to be lagging in their commitments.
Canada was once a recipient of not one, but two special editions: the Lifetime Underachievement Award, and the Colossal Fossil Award.
This year so far, while Belgium and New Zealand have been singled out, Canada has yet to be mentioned.
That doesn't mean it won't happen. But Canada's absence may also signal a shift in how the country is currently being perceived, at least in this early going.
The change in tone on climate change, and Prime Minister Justin Trudeau's positive words Monday have been noted by environmentalists and other delegates.
So have the provincial initiatives to cut carbon emissions, and Canada's $2.65-billion contribution to help developing countries design their own national plans to cut emissions.
"That's an early sign that it's a change of attitude and tone. But it's going be really important that Canada shows its colours in its negotiating stance in the course of the next two weeks," said Greenpeace's Davis.
"Lots of countries and lots of civil society will be looking to Canada to lead a march toward a 100 per cent renewable energy future and away from fossil fuels completely," she says.