Greta Thunberg is hopeful the student climate strike on Friday can bring about positive change, as young people in more and more countries join the protest movement she started last summer as a lone campaigner outside the Swedish parliament.

Teenage activist takes School Strikes 4 Climate Action to Davos Read more

The 16-year-old welcomed the huge mobilisation planned in the UK, which follows demonstrations by tens of thousands of school and university students in Australia, Belgium, Germany, the United States, Japan and more than a dozen other countries.

“I think it’s great that England is joining the school strike in a major way this week. There has been a number of real heroes on school strike, for instance in Scotland and Ireland, for some time now. Such as Holly Gillibrand and the ones in Cork with the epic sign saying ‘the emperor is naked’,” she told the Guardian.

With an even bigger global mobilisation planned for 15 March, she feels the momentum is now building.

“I think enough people have realised just how absurd the situation is. We are in the middle of the biggest crisis in human history and basically nothing is being done to prevent it. I think what we are seeing is the beginning of great changes and that is very hopeful,” she wrote.

Facebook Twitter Pinterest Greta Thunberg strikes outside the Swedish parliament last summer. Photograph: Michael Campanella/The Guardian

Thunberg has risen rapidly in prominence and influence. In December, she spoke at the United Nations climate conference, berating world leaders for behaving like irresponsible children.

Last month, she had similarly harsh words for the global business elite at Davos. She said: “Some people, some companies, some decision-makers in particular, have known exactly what priceless values they have been sacrificing to continue making unimaginable amounts of money. And I think many of you here today belong to that group of people.”

I'm striking from school to protest inaction on climate change – you should too | Greta Thunberg Read more

The movement she started has morphed and grown around the world , and, at times, linked up with older groups, including Extinction Rebellion, 350.org and Greenpeace.

Next week she will take the train – having decided not to fly due to the high carbon emissions of aviation – to speak at an event alongside Jean-Claude Juncker, the president of the European commission, in Brussels, and then on to Paris to join the school strikes now expanding in France.

Play Video 1:20 Thousands of UK students strike over climate change – video

Veteran climate campaigners are astonished by what has been achieved in such a short time. “The movement that Greta launched is one of the most hopeful things in my 30 years of working on the climate question. It throws the generational challenge of global warming into its sharpest relief, and challenges adults to prove they are, actually, adults. So many thanks to all the young people who are stepping up,” said Bill McKibben, the founder of 350.org.

Around the world, so many student strikes are now taking place or planned that it is becoming hard to keep up. On Twitter, a supporter who posts under the name The Dormouse That Roared, has compiled a Google map that pins all the reported or announced locations, stretching from Abuja and Bugoloobi to Sacramento and Medellín. “This is not perfect by any means. It’s an emergency after all,” the online campaigner told the Guardian.

The most recent version shows thick clusters of activity, particularly in the UK and northern Europe. “#climatestrike. The house is on fire. Just wow!” wrote @dormouseroared, who is also collecting the different terms for “climate strike” in different languages.

In reply, people on Twitter have written, “I’ve been dreaming of this”, “Power to the children”, “beautiful” and simply “hope”.

Australia was one of the first countries to mobilise. Last November, organisers estimate 15,000 students went on strike. Last Friday, students lobbied outside the offices of the opposition party. On 1 March, they will target the federal treasurer’s office. Two weeks later, they will join the global strike.

Facebook Twitter Pinterest Students on strike in Sydney. Photograph: Mike Bowers/The Guardian

They are demanding immediate political action to stop the Adani coalmine in Queensland, and a switch from fossil fuels to 100% renewable energy.

On Thursday, three student activists from Castlemaine in Australia – Callum Bridgefoot, 11; Harriet O’Shea Carre, 14 and Milou Albrechy,14 – spoke with the leader of the opposition in the federal parliament. “It’s a good sign that he is willing to meet,” they said. “The prime minister condemned the strike.”

Academics back UK schools' climate change strikes Read more

The resources minister Matt Canavan was still more hostile, saying students would be better off learning about mining and science. “These are the type of things that excite young children and we should be great at it as a nation,” he told a local radio station. “The best thing you’ll learn about going to a protest is how to join the dole queue.”

In Belgium, there have been strikes by thousands of students for at least four consecutive weeks, with one now-famous placard – addressed to politicians and policymakers – reading: “I’ll do my homework when you do yours.”

More than 3,000 scientists have given their backing to the strikes. The Belgian government is clearly feeling the pressure. The environment minister was forced to resign after falsely claiming the country’s intelligence services held evidence that the striking children were being directed by unnamed powers. The allegation was quickly contradicted by intelligence chiefs.

Switzerland has seen some of the biggest actions. Local activists said 23,000 joined the strike on 18 January, followed by 65,000 on 2 February. They too are preparing for the global demonstration on 15 March. They want the government to immediately declare a climate state of emergency, implement policies to be zero-carbon by 2030 without geo-engineering, and if necessary move away from the current economic system.

Activists said they want to make clear that the problem is systematic rather than a matter of individual lifestyle choices. They have been criticised by right-wing politicians, but local governments have met student delegations to discuss short-term steps, such as a ban on any school trip that involves a flight. One regional authority has declared its support for the student movement. In an election year, state leaders have also expressed guarded support.

“For the moment, the government has reacted in a very paternalistic way. They say that it’s a good sign that the youth is demonstrating for its future but they don’t really do anything about it,” said Thomas Bruchez, a 20-year-old student at the University of Geneva. In two weeks, he said the organisers will prepare for the next nationwide strike, when they will consider how to involve workers and try to define more precise claims, such as free public transport financed by highly progressive taxes.

In Germany, activists told the Guardian there are mobilisations every week. Last Friday, there were 20,000 students striking in 50 cities. On 18 January, there were 30,000. And there will be another strike this Friday in at least 30 cities.

Facebook Twitter Pinterest Students protest for climate action in Magdeburg, Germany. Photograph: Klaus-Dietmar Gabbert/AP

The global strike on 15 March is expected to be the biggest yet with mobilisations in 150 cities. “It is not acceptable that grown-ups are destroying the future right now,” said Jakob Blasel, a high-school student. “Our goal to stop coal power in Germany and fossil energy everywhere.” He said politicians have expressed admiration for their campaign, but this has not translated into action. “This is not acceptable. We won’t stop until they start acting.”

Until now 75% of the participants have been schoolchildren but increasing numbers of university students are joining. Luisa Neubauer, a 22-year-old, was among those invited to talk to senior cabinet officials. She told the German minister of economy that he was part of the problem because he was working for industry, rather than for people or the planet.

“What we need our politicians and our government to understand is that everything they do today comes at a price for future generations,” she said. “We are not doing this for fun, but because we don’t have a choice.”

But she too noted a new direction in the national discussion. “There is a debate now about climate and the environment, which is good. People for the first time in years are not talking about refugees but talking about the environment.”

