The green light is dancing up and down the giant steel construction, turning the monument of Paris into a virtual forest. I have come to see the illumination of the Eiffel Tower after another long day at COP21, and it feels almost as refreshing as a nature trip.
The installation of artist Naziha Mestaoui is part of the City's program for the climate conference. It's a green exclamation mark, 324 metres high, telling that the nations of the world have come to Paris to protect nature and to fight climate change.
Out at the conference centre in Le Bourget, where the nations of the world sit in small meeting rooms and discuss how, exactly, we're going to make it, there is also an Eiffel Tower. This is probably here for those delegates who never make it into town. The biggest difference between our tower and the real one, apart from the size, is the colour: The COP21 version is illuminated red.
While the intent of this remains open (warning? Global heating? Stop light?), colours definitely have a meaning at the climate conference. At the convention centre there is the green zone, an exhibition space everyone can attend. But the negotiations are happening in the blue zone, behind the airport-like security controls, and only registered participants are allowed to enter.
I have the privilege to pass. Inside, my yellow badge gives me access to most of the rooms, but only the purple badges of the delegates open all doors. As a member of the "civil society", as we are called here, I am often stopped at the entrance of a negotiation room.
But the civil society representatives find other ways to make their statements, especially the young ones. Many of them have painted a circle around one eye: a call for zero emissions until 2050. "It is also a signal for the delegates in the negotiations", Annabelle Acton-Bond says: "Our eyes are on them."
Annabelle is 24 and from the UK Youth Climate Coalition. She has come to the COP meeting to promote a more ambitious long-term target: to limit global warming to 1.5 degrees instead of the current target of 2 degrees.
Talking with Annabelle is even more refreshing than the quasi-nature trip to the Eiffel Tower. I am impressed and inspired by her commitment and engagement.
And there is more youth power to meet. I am invited to a talk of Swedish organisations with the negotiation delegation of Sweden. It's mostly young people packed in the small room in the Nordic pavillon. Anna Lindstedt, chief negotiator for Sweden, asks for input. And the youngsters provide her with clear and concrete expectations.
A representative of the Sami people has carefully read the draft version of the planned Paris agreement and is unsatisfied with the formulations about human rights of people. She wants to ensure that minorities like the Sami are heard. Anna Lindstedt promises to take the question to the negotiations.
Will it ever be possible to come to an agreement next week, with all individual interests that should be addressed? One Swedish delegate was also at the COP15 conference in Copenhagen 2009 when the expectations were high but no agreement was achieved. For Paris, he is more optimistic. "The preparation has been much better this time", he says.
And also the weather helps, with temperatures around 14 degrees in November-Paris. "At the Copenhagen meeting it was snow storming all the time", the delegate says. "Now we have the warmest year ever - the effects of climate change become clearer."
Vattenfall’s coverage of the COP21 climate change talks in Paris
Vattenfall's Head of Communications Ivo Banek is attending the climate conference COP21 in Paris as an observer. Here, he writes about his personal impressions.
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