By Hans Lee, Philip Blenkinsop, Fabrizio Bensch and Ilze Filks
SYDNEY/BRUSSELS/BERLIN/STOCKHOLM, Sept 20 (Reuters) - Hundreds of thousands of students and workers left their schools, colleges and offices on Friday and marched along city streets around the globe to demand that world leaders take urgent action to avert an environmental catastrophe.
The global climate strike, inspired by 16-year-old Swedish activist Greta Thunberg, kicked off in the Pacific islands and followed the rising sun across Australia, Japan, Southeast Asia and then on to Europe, Africa, the Middle East and the Americas.
It will culminate in New York when Thunberg, who has been nominated for a Nobel Peace Prize, will spearhead a rally at the United Nations headquarters, where heads of government are due to gather for a climate summit next week.
"This is about my future, not only my future, but the future of my entire generation and all the generations to come after ours," said Tristan Vancleef, 16, among around 15,000 demonstrators who marched through the centre of Brussels.
Banners at the Brussels march included "Cool kids save the hot planet", "I won't go to school until you make it cool" and "The warm earth destroys our cold beer."
Protesters in about 150 countries are calling on governments to take immediate action to limit the harmful effects of manmade climate change.
Social media posts showed scores of demonstrations, ranging from a few dozen primary school children in Abuja, Nigeria, to tens of thousands of people in cities from Hamburg, in Germany, to Melbourne, Australia.
Britain's opposition leader Jeremy Corbyn tweeted that 100,000 people joined the demonstration in London.
"Our future on your shoulders," read one banner stretched across a street by students in Berlin.
"Our oceans are rising, so are we," was a popular slogan on placards in many places, including one carried by a student in school uniform in Melbourne and another by a girl wearing a facemask in Kolkata, in eastern India.
Among the students gathering in New York's Foley Square ahead of a midday march was Alexandria Villasenor, a 14-year-old who has been striking outside the UN every Friday since Dec. 14.
"We're telling adults to step up and back us up with our strikes because we need everyone to tell the leaders at the global climate summit that they need to take climate action," she said.
Global warming caused by heat-trapping greenhouse gases from burning fossil fuels has already led to droughts and heatwaves, melting glaciers, rising sea levels and floods, scientists say.
Carbon emissions climbed to a record high last year, despite a warning from the U.N.-backed Intergovernmental Panel on Climate Change in October that output of the gases must be slashed over the next 12 years to stabilise the climate.
The protest movement is putting increasing pressure on both governments and companies to respond.
Online retail giant Amazon.com Inc pledged on Thursday it would be net carbon neutral by 2040.
Cutting emissions is a challenging goal for Amazon, which delivers 10 billion items a year and has a massive transport and data centre footprint. "We know we can do it and we know we have to do it," Chief Executive Officer Jeff Bezos said.
Environmental advocacy group Greenpeace USA welcomed the commitment, but a spokesman said the company lagged peers Google, Apple and Facebook in transparency around its renewable projects.
Some of the company's workers from the group Amazon Employees for Climate Justice plan to join marches on Friday.
In Europe, German Chancellor Angela Merkel unveiled a major new climate protection package thrashed out by parties in her coalition in all-night talks.
Meanwhile, on the streets of the capital, crowds gathered at the Brandenburg Gate, where three activists stood on blocks of ice beneath a mock gallows.
The U.N. summit next week brings together world leaders to discuss climate change mitigation strategies, such as transitioning to renewable energy sources from fossil fuels.
U.S. President Donald Trump and Brazilian President Jair Bolsonaro, among the world's only national leaders that publicly question climate science, are not due to take part, their representatives said.
The issue of global warming is vital to low-lying Pacific islands, which have repeatedly asked wealthier nations to do more to prevent rising sea levels.
As Friday's day of action got underway across scattered Pacific communities, students holding placards in Kiribati chanted: "We are not sinking, we are fighting".
By mid-afternoon across Europe, the Middle East and Africa, crowds had gathered in many cities, including London, Paris, Brussels, Berlin, Warsaw, Stockholm, Helsinki, Beirut, Nairobi and Cape Town. Protests were also getting started in many American cities, including New York and Washington D.C.
In Stockholm, crowds gathered outside the Swedish parliament, where Thunberg began her "Fridays for Future" school strike protests last year.
"We have to send a message to the politicians that the environment is more important than education," said Mattis Johanssen, 18.
Earlier, Danielle Porepilliasana, a Sydney high school student, had a blunt message for politicians such as Australian Finance Minister Mathias Cormann, who told parliament on Thursday that students should stay in class.
"World leaders from everywhere are telling us that students need to be at school doing work," she said, wearing anti-coal earrings. "I'd like to see them at their parliaments doing their jobs for once."
(Reporting by Hans Lee in Sydney, Philip Blenkinsop in Brussels, Fabrizio Bensch in Berlin and Ilze Filks in Stockholm Hans Lee in Sydney; Additional reporting by Patpicha Tanakasempipat in Bangkok, Byron Kaye in Sydney, Sonali Paul in Melbourne, Katharine Houreld in Nairobi, Gabriella Borter in New York and Reuters Television; Writing by Jonathan Barrett, Stephen Coates and Alex Richardson; Editing by Lincoln Feast, Janet Lawrence and Mike Collett-White)
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