It was still dark when Victoria and five other young women emerged from a customized truck to climb the Shard, Europe's biggest skyscraper. She was carrying a backpack weighing about 30 pounds -- about as heavy as a suitcase for a two week vacation. At best she'd slept for three hours the night before, laid out on a camping mattress at Greenpeace UK's London office.

By 4:30 a.m. she was secured by ropes to the glass structure, ready to attempt the first ever 'free climb' of a very 21st century landmark. Without permission, but with months of training and years of climbing experience, the adrenaline levels were hard to manage. Every movement must be deliberately slow, fighting the urge to rush, to evade police, to burn the energy pulsing through her heart.

As the sun rose over the Thames the world's media began to shift their attention to the climbers. By midday reports of the women's attempt had reached Singapore and India,images of six tiny figures against a colossal glass edifice catching the eye of editors across the world. Hundreds of thousands discussed the climb on social media, all asking questions. Why are they doing this? Who are these women? Will they make it to the top?

In terms of human achievement alone this was something special. Their courage is quite staggering when you consider the height of the building and the 14 hours of intense effort it took to get to the top. When thousands of office workers picked up their smartphones to tweet their support, or share pictures of the climb on Instagram, there was a sense of something new being born. Young people are supposed to be apathetic and indifferent, not interested in politics or world events. These women had something to say and they were literally shouting from the rooftops to get it heard. So what gives?

The melting Arctic is a story that will define our place in history. We've lost so much of the sea ice up there that within a few years there will be nothing left in the summer months. This has happened over the course of a single human lifetime, and it's up to the same generation to decide what we do about it. Companies like Shell want to exploit the melting ice to drill for more oil, ignoring science and justice to squeeze a couple more decades of profit while the world warms. Victoria is just one of over three million people who have risen up to stop them, a new movement made up of young and old, North, South, East and West. Young people especially understand this with a simple clarity that should embarrass today's meek political elite.

As the late summer sun painted London in glorious gold, our six young heroes reached the top of a huge pyramid. When messages flooded in from Argentina and Colombia, Australia and Kenya, they knew that they were supported and loved by all these people, a movement that is growing every day. The oil companies may have all the money in the world, but we have truth, creativity and youth on our side. Big moments like Thursday won't happen every day, but they will happen again. And in the meantime millions of individual acts of bravery will strengthen the movement. From beautiful posters to local gatherings, these small moments of defiance are building an unstoppable global wave. We can't all climb into the clouds, but each of us can help in our own different way. Oil companies like Shell rely on secrecy, on apathy, and the collective belief that some things are impossible to achieve. Yesterday's climb was terrifying for those of us watching at home, but it scared them most of all.


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