A UN climate summit in New York in September will give world leaders an opportunity to address the "ecological emergency" of global warming after years of inaction, Sweden's Greta Thunberg told a meeting of young climate activists in Lausanne, Switzerland, on Monday.

"I think this is a great opportunity for world leaders to show that they have actually listened to us and to the science ... Now they will have to prove that," said the 16-year-old Thunberg, who inspired the youth climate movement Fridays for Future with her weekly school strikes in her home country.

Read more: Will it soon be too late to save the climate?

Thunberg held weekly Friday protests outside the Swedish Parliament for months

Emissions-free travel plans

Thunberg said that although "lots of things" had happened in the past year, global emissions of greenhouse gases had not gone down, "so we're still back on square one." She called for continued protests, including in Asia, where there have been fewer school strikes.

Her remarks were made to an audience of some 450 activists from 38 European countries.

After the week-long meeting in Lausanne, Thunberg is to travel to the UK, from where she plans to sail across the Atlantic in the emissions-free yacht Malizia II to attend the New York Climate Action Summit on September 23 on the sidelines of the UN's annual General Assembly meeting. The trip, whose starting date depends on the weather, is expected to take about two weeks.

She will also be joining the annual UN climate change conference in Chile in December. Thunberg does not travel by plane owing to the high climate impact of flying.

Read more: July 2019 was world's hottest month ever recorded

The Malizia II generates its own electricity with solar panels, propellers and underwater turbines

Little progress made

Thousands of young protesters worldwide have followed Thunberg's example and skipped school on Fridays to publicly voice their concern about global warming and put pressure on politicians to act on the recommendations of the UN-backed Intergovernmental Panel on Climate Change (IPCC).

On Monday, one of Germany's largest unions, Verdi, called on its members to join the Fridays for Future protests as well, with Verdi head Frank Bsirske telling the Westdeutsche Allgemeine Zeitung newspaper that "we need a much more consistent approach to climate change policy." He said, however, that he was not calling on union members to skip work, but attend the demonstrations at the end of their shifts.

Despite a warning from the IPCC in October that emissions of greenhouse gases will have to be drastically reduced over the next 12 years to stop the Earth warming to dangerous levels, carbon emissions reached a new high last year. Scientists say that human output of such gases from burning fossil fuels since the beginning of the Industrial Revolution has already led to heat waves, droughts and other extreme weather phenomena.

Read more: Psychology behind climate inaction: How to beat the 'doom barrier'

tj/msh (AP, Reuters, dpa)

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