By Laurie Goering
NEW YORK, Sept 20 (Thomson Reuters Foundation) - Ben Davis' father spent his career working at a petroleum company. But on Friday, Davis - a chemical engineer, like his dad - did something he'd never done before.
He joined Swedish teenage activist Greta Thunberg in a protest to demand action on climate threats.
"We've run out of time for gradual change," said the 38-year-old university teacher, who took the day off work to answer a call by student climate protesters for adults to join them for the first time Friday in a global strike.
"I understand the magnitude of the problem. For me the science is not confusing or ambiguous. We need drastic change," he said. "That I'm out here should trouble a lot of people."
Friday's marches, in cities from New York to London and Johannesburg to New Delhi, had been expected to be the largest climate change protests yet, spurred partly by adding adults to the past year's mainly youth-led mobilizations.
Global climate campaign group 350.org said late Friday afternoon that organizers estimated more than 4 million people had taken to the streets. About 3,000 companies closed their doors in support of the climate strikes, it said.
The protests, in advance of a U.N. summit Monday aimed at accelerating action to tackle global warming, kicked off a week in which more than 5,800 climate change-related strikes and other events are set to take place in 163 countries, 350.org said in a statement.
New York City officials estimated that 60,000 people marched there. Steel workers, nurses and other unionized employees joined the Manhattan protest, already swelled after city authorities let children miss school without penalty Friday.
Many of the adults on the streets of New York said it was the first time they had picked up a protest sign over climate threats.
Justin Flood, 37, a graphic designer, said the global advertising agency he works for had shut its doors entirely Friday to let its staff join the rally.
"I feel like protest is the only way to have an outlet for the anxiety around this issue," said Flood, who carried a sign reading, "Sorry we're closed due to climate crisis".
With the planet's climate showing signs of reaching dangerous tipping points, but politicians failing to act on them, "what else are we going to do?" he asked.
Around him, marchers - the majority of them students - chanted and waved banners with messages ranging from "Don't Be a Fossil Fool" to "Act Now or Swim Later".
Richard Evans, 61, joined the New York rally after traveling three and a half hours from his home in rural Pennsylvania with his wife, a teacher.
They hefted a homemade banner made from an old sheet: "Face reality now, for our children".
Evans, an ecologist who works for the U.S. national park service, said he'd helped switch the park he works at entirely to wind power.
He had once had faith a transition to clean energy - a crucial part of limiting climate change - was well underway in the United States.
"I tried to be patient, but when things started going backward, I lost my patience," he said, referring to moves by President Donald Trump's administration to promote fossil fuels.
"I can understand slow progress, but not going backward and disrespecting science," he said.
Evans said he had never protested before and hated crowds, adding it was "contrary to my whole personality to be out here".
But writing to politicians had not worked, he said.
"People say these protests don't do anything. But they are a red flag that if nothing happens this (movement) is going to get bigger," he said.
Alethea Shapiro, 40, had another reason for joining the protests with her four children: She'd seen the destruction of Hurricane Sandy in 2012 firsthand, when a huge tree fell on part of their house in Long Island.
"In the last year the natural disasters have really picked up, from fires to hurricanes," she said. But "there's still a disconnect. People should be paying attention but they're not."
Kacy Wiggins, 50, who skipped work as a math lecturer to attend the rally with his 12-year-old daughter, said he feared the protests would have little immediate effect.
"Real change won't come until these students are old enough to vote," he predicted. But the protests "are an omen" of political change coming, he said.
Sukhman Dhami, 41, a human rights lawyer and another first-time climate protester, however, saw the strikes as a crucial step in spurring the measures needed to reduce climate risks.
"Scientists establish the facts but it's up to communities and people to demand everyone act on this," he said, predicting the protest movement "absolutely" would begin to shift policy over time.
"Greta Thunberg has inspired millions of Gretas - young and old," he said.
(Reporting by Laurie Goering @lauriegoering; editing by Megan Rowling. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, climate change, resilience, women's rights, trafficking and property rights. Visit http://news.trust.org/climate)
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