From activists in angel wings to armed police and carefully sorted refuse, the much-awaited Paris climate talks opened Monday with a touch of spectacle, hefty security and lofty rhetoric.
Helicopters hovered overhead while a kaleidoscope of people from nearly every nation hustled between scores of meetings and events scattered across a sprawling 18-hectare (40-acre) site just north of the French capital.
Le Bourget, for now, is a microcosm of the world—a temporary city of 40,000 people, from suave negotiators in business suits to indigenous activists in traditional clothing and harried journalists.
As world leaders delivered speeches in plenary halls, some delegates, exhausted from long flights and eyeing the gruelling road ahead, took the opportunity of a snooze on sofas in rest areas.
"It's busy, you know. You need just the first few days to get your head around it," said Kim Shore, 30, an Australian man who leads a youth organisation. "It's a marathon, not a sprint."
Some 195 nations will spend the next 11 days negotiating what is being touted as a landmark post-2020 deal to roll back global warming, preserving the planet's climate system for future generations.
Some of that effort has a trade show quality, with brochures and business cards being handed out by an array of national delegations and campaign groups.
But the gathering remains very much focused on weighty issues, with language to match.
"Our government is inexcusable to continue its coal mining policy. It pollutes not just Australia, but the whole world," said Deborah Hart of ClimActs, a theatre troupe of Australian climate campaigners.
Clad in white, with gauzy angel wings on their backs, the activists greeted visitors in front of the summit, waving signs that said "Coal kills" and "Climate justice, no excuses".
Before making it into the venue visitors must pass through tight security. Heavily-armed soldiers and police stand guard at the perimeter of the grounds.
Armed United Nations guards, wearing shirts in the organisation's signature shade of blue, patrol the halls.
Security is on high alert just weeks after terror attacks in Paris killed 130 people, most of them young people out for the night at bars, restaurants and a concert in a trendy neighbourhood.
Just like at the airport, visitors to the conference have to go through metal detectors, shedding their belts and emptying their pockets into plastic trays. Laptops are sent through the X-ray machine along with bags.
Guards shepherded the 150 world leaders—who kicked off the event with hours' worth of speeches on Monday—between restricted areas. Some 2,800 police have been deployed to keep the summit safe.
Being a climate conference, Le Bourget is also awash with go-green messages.
Organisers handed out thousands of reusable plastic water bottles to cut down on waste, while attendants stood near trash cans advising visitors on how not to mix up their recyclables and what is headed for the dump.
Still, the event is expected to produce 21,000 tonnes of greenhouse gases—equal to the annual carbon dioxide emissions of 4,420 cars.
The pollution will be compensated by CO2-curbing projects in the southern hemisphere, the French government says.
Organisers also set up some ways for those emissions to never reach the atmosphere. People pumped their legs at a pedal-powered electronic device charging station on Monday.
"I'm trying to get in a little fitness too," said Sebastian Cardenas, 32, of Ecuador, who was observing the talks.
As he pedalled he noted the battery life on his computer had already gone up a few bars.
"Not bad for a few minutes' work," he said.
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