My name is Greta Thunberg, I am 16 years old and I’m from Sweden. I am grateful for being with you here in the USA. A nation that, to many people, is the country of dreams.

I also have a dream: that governments, political parties and corporations grasp the urgency of the climate and ecological crisis and come together despite their differences – as you would in an emergency – and take the measures required to safeguard the conditions for a dignified life for everybody on earth.

Because then – we millions of school striking youth – could go back to school.

I have a dream that the people in power, as well as the media, start treating this crisis like the existential emergency it is. So that I could go home to my sister and my dogs. Because I miss them.

In fact I have many dreams. But this is the year 2019. This is not the time and place for dreams. This is the time to wake up. This is the moment in history when we need to be wide awake.

And yes, we need dreams, we can not live without dreams. But there’s a time and place for everything. And dreams can not stand in the way of telling it like it is.

Greta Thunberg inspires climate activists everywhere: In pictures Show all 12 1 /12 Greta Thunberg inspires climate activists everywhere: In pictures Greta Thunberg inspires climate activists everywhere: In pictures In the protest that started a movement, Greta skips school to sit outside of the Swedish parliament in Stockholm in order to raise awareness of climate change on 28 August 2018 Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta speaks at the World Economic Forum in Davos on 25 January AFP/Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta stages a protest at the World Economic Forum in Davos on 25 January Reuters Greta Thunberg inspires climate activists everywhere: In pictures Greta speaks at the House of Commons in London on 23 April PA Greta Thunberg inspires climate activists everywhere: In pictures Greta addresses to the occupation at Marble Arch in London on 21 April AFP/Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta meets the pope on a visit to Rome Reuters Greta Thunberg inspires climate activists everywhere: In pictures Greta speaks at the senate in Rome on 18 April Reuters Greta Thunberg inspires climate activists everywhere: In pictures Greta addresses a debate of the EU Environment, Public Health and Food Safety committee at the European Parliament in Strasbourg on 16 April AFP/Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta receives the Special Climate Protection Award at the German Film and Television awards in Berlin on 30 March AFP/Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta attends a children's climate protest in Berlin on 29 March AFP/Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta addresses a children's climate protest on 1 March in Hamburg Getty Greta Thunberg inspires climate activists everywhere: In pictures Greta attends a meeting for the Civil Society For rEUnaissance at the EU Charlemagne Building in Brussels on 21 February AFP/Getty

And yet, wherever I go I seem to be surrounded by fairytales. Business leaders, elected officials all across the political spectrum spending their time making up and telling bedtime stories that soothe us, that make us go back to sleep.

These are “feel-good” stories about how we are going to fix everything. How wonderful everything is going to be when we have “solved” everything. But the problem we are facing is not that we lack the ability to dream, or to imagine a better world. The problem now is that we need to wake up. It’s time to face the reality, the facts, the science.

And the science doesn’t mainly speak of “great opportunities to create the society we always wanted”. It tells of unspoken human sufferings, which will get worse and worse the longer we delay action – unless we start to act now. And yes, of course a sustainable transformed world will include lots of new benefits. But you have to understand. This is not primarily an opportunity to create new green jobs, new businesses or green economic growth. This is above all an emergency, and not just any emergency. This is the biggest crisis humanity has ever faced.

And we need to treat it accordingly so that people can understand and grasp the urgency. Because you can not solve a crisis without treating it as one. Stop telling people that everything will be fine when in fact, as it looks now, it won’t be very fine. This is not something you can package and sell or ”like” on social media.

Stop pretending that you, your business idea, your political party or plan will solve everything. We must realise that we don’t have all the solutions yet. Far from it. Unless those solutions mean that we simply stop doing certain things.

Changing one disastrous energy source for a slightly less disastrous one is not progress. Exporting our emissions overseas is not reducing our emission. Creative accounting will not help us. In fact, it’s the very heart of the problem.

Some of you may have heard that we have 12 years as from 1 January 2018 to cut our emissions of carbon dioxide in half. But I guess that hardly any of you have heard that there is a 50 per cent chance of staying below a 1.5 degree Celsius of global temperature rise above pre-industrial levels. Fifty per cent chance.

And these current, best available scientific calculations do not include non linear tipping points as well as most unforeseen feedback loops like the extremely powerful methane gas escaping from rapidly thawing arctic permafrost. Or already locked in warming hidden by toxic air pollution. Or the aspect of equity; climate justice.

So a 50 per cent chance – a statistical flip of a coin – will most definitely not be enough. That would be impossible to morally defend. Would anyone of you step onto a plane if you knew it had more than a 50 per cent chance of crashing? More to the point: would you put your children on that flight?

And why is it so important to stay below the 1.5 degree limit? Because that is what the united science calls for, to avoid destabilising the climate, so that we stay clear of setting off an irreversible chain reaction beyond human control. Even at 1 degree of warming we are seeing an unacceptable loss of life and livelihoods.

So where do we begin? Well I would suggest that we start looking at chapter 2, on page 108 in the IPCC report that came out last year. Right there it says that if we are to have a 67 per cent chance of limiting the global temperature rise to below 1.5 degrees Celsius, we had, on 1 January 2018, about 420 Gtonnes of CO2 left to emit in that carbon dioxide budget. And of course that number is much lower today. As we emit about 42 Gtonnes of CO2 every year, if you include land use.

With today’s emissions levels, that remaining budget is gone within less than 8 and a half years. These numbers are not my opinions. They aren’t anyone’s opinions or political views. This is the current best available science. Though a great number of scientists suggest even these figures are too moderate, these are the ones that have been accepted by all nations through the IPCC.

And please note that these figures are global and therefore do not say anything about the aspect of equity, clearly stated throughout the Paris Agreement, which is absolutely necessary to make it work on a global scale. That means that richer countries need to do their fair share and get down to zero emissions much faster, so that people in poorer countries can heighten their standard of living, by building some of the infrastructure that we have already built. Such as roads, hospitals, schools, clean drinking water and electricity.

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The USA is the biggest carbon polluter in history. It is also the world’s number one producer of oil. And yet, you are also the only nation in the world that has signalled your strong intention to leave the Paris Agreement. Because quote “it was a bad deal for the USA”.

Four-hundred and twenty Gt of CO2 left to emit on 1 January 2018 to have a 67 per cent chance of staying below a 1.5 degrees of global temperature rise. Now that figure is already down to less than 360 Gt.

These numbers are very uncomfortable. But people have the right to know. And the vast majority of us have no idea these numbers even exist. In fact not even the journalists that I meet seem to know that they even exist. Not to mention the politicians. And yet they all seem so certain that their political plan will solve the entire crisis.

But how can we solve a problem that we don’t even fully understand? How can we leave out the full picture and the current best available science?

I believe there is a huge danger in doing so. And no matter how political the background to this crisis may be, we must not allow this to continue to be a partisan political question. The climate and ecological crisis is beyond party politics. And our main enemy right now is not our political opponents. Our main enemy now is physics. And we can not make “deals” with physics.

Everybody says that making sacrifices for the survival of the biosphere – and to secure the living conditions for future and present generations – is an impossible thing to do.

Americans have indeed made great sacrifices to overcome terrible odds before.

Think of the brave soldiers that rushed ashore in that first wave on Omaha Beach on D Day. Think of Martin Luther King and the 600 other civil rights leaders who risked everything to march from Selma to Montgomery. Think of President John F. Kennedy announcing in 1962 that America would “choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard…”

Perhaps it is impossible. But looking at those numbers – looking at the current best available science signed by every nation – then I think that is precisely what we are up against.

But you must not spend all of your time dreaming, or see this as some political fight to win.

And you must not gamble your children’s future on the flip of a coin.

Instead, you must unite behind the science.

You must take action.

You must do the impossible.