Try to pinpoint a moment when the climate crisis finally pierced the public consciousness and you will struggle.
Was it Swedish teen Greta Thunberg refusing to go to school because she felt she had no future? Or Environment Secretary Michael Gove agreeing to meet activist group Extinction Rebellion after their civil disobedience brought cities to a standstill?
Perhaps it was the heartbreaking scenes of an albatross regurgitating plastic to feed its young in Sir David Attenborough’s Blue Planet.
Whatever the answer, when the floodgates finally opened on the issue of climate change, the Green Party was ready to take full advantage at the ballot box.
The Greens gained almost 200 seats in Thursday’s local election. Although the headlines were taken up by the Lib Dems gaining 600 seats and the Conservatives losing more than 1,000, the result was the Greens’ best-ever.
And the feat stretched far beyond its strongholds in the areas of Bristol and Brighton, with victories in Brexit-backing traditionally-Labour areas of the North East, such as South Tyneside and Washington, and progress in areas they already have a base, like the Wirral and Peterborough.
But if the issues of bin collections, greenbelt housing plans and library closures featured highly in the town hall polls, Brexit was also in the back of many voters’ minds.
Theresa May’s seemingly-endless battle to pull the UK out of Europe and Jeremy Corbyn’s refusal to give his full-throated backing to a second referendum too played a part in the Green surge.
Ahead of the impending European parliament elections on May 23, HuffPost UK talked to new Green voters up and down the UK about why they switched.
‘The Greens are more progressive’
Life-long Labour supporter Susan Bax, a 56-year-old radiographer, backed her local Green candidate in Cheshire West after being turned off by Corbyn’s socialism.
She said: “I do think that the Greens are more progressive and are looking for modern solutions to complex problems rather than, for example, reopening coal mines.
“I have two children at uni who are cross about the old, stale parties and how their future is being screwed so wanted to do something to support them.
“My background is very northern working class traditional Labour, but we can’t go back to 1970s Britain – that’s where Labour have lost it for me.”
‘Jeremy Corbyn has completely fudged Brexit’
Civil servant Dan Parker, 21, voted Green in the Tory heartland of Hartley, Sevenoaks, Kent.
“I voted Green for their anti-Brexit stance and on environmental issues,” she said. “I did completely vote on Westminster issues. Jeremy Corbyn has completely fudged Brexit.
“This area is so strongly Conservative and our MP is very pro-Leave. There aren’t many alternatives if you are anti-Brexit and there was no Lib Dem candidate so my choice was made for me.”
‘I found it very, very difficult to tick the Labour box this time’
Jack Hodgkinson, a 22-year-old university student, switched from voting Labour to Green in Worcestershire’s Redditch.
“I found it very, very difficult to tick the Labour box this time,” he said. “I cannot deal with their constant prevarication on Brexit, they need to back a second referendum in my opinion, but won’t.
“But it isn’t purely on Brexit that I voted. I want to replace our first-past-the-post voting system and I think the Greens will bring us closer to doing that.
“I think a lot of people my age also feel like the Lib Dems are tarnished by the Coalition. I feel like they are just a little bit to the right of the Labour Party and not radical enough to give us change.”
Tim Leach, 34, a novelist and assistant professor, was among those who boosted the number of Green councillors in Sheffield.
He said the pull toward the party, which is led by Sian Berry and Jonathan Bartley, has a more profound driver.
“My vote should be won,” he said, adding that he despaired of Labour’s anti-Semitism crisis and the number of allegations of Islamophobia emanating from the Tories’ rank and file.
“I just want to vote for a party that isn’t involved in a major racism crisis - that shouldn’t be a high bar to clear but apparently it is,” he said.
Adding he saw Caroline Lucas, the Greens’ sole MP as a “sensible voice in parliament”, he said the issue of climate change was paramount.
“It does feel like in the last year or so the environment and green issue are more a priority for people,” he said. “I know among the people I talk to there is a lot of frustration at the lack of political will to engage with the issues seriously.
“A lot of people my age are feeling very anxious about the environment. They are having dreams and it is actively waking them up in a cold sweat in the middle of the night frightened for the future.
“Friends of mine are seriously weighing up whether to have kids because of the anxiety they feel over the environment.
“It used to be a small subject on the fringes but now it is part of regular dialogue.”
‘They think that voters don’t have anywhere else to go, but we do now’
Helen Furnivall is a 46-year-old mum-of-three who owns a PR agency in Manchester. She voted Green in Brexit-backing Stockport.
“There has not been a single election where I have not voted Labour but this time I could not bring myself to do it and I’m not sure I will vote Labour ever again,” she said.
“They think that voters don’t have anywhere else to go but we do now.
“The Greens are a party of remain and I have been hugely impressed with Extinction Rebellion. That was young people showing politicians that they have a voice. But these young people are not being heard by the political parties.
“Brexit and climate change are such huge issues and if the main parties do not get to grips with them then young people just are not going to vote for them.”
Furnivall will vote Green again in the European elections on May 23.
“Me and my husband both vote Green. It is more about the next generation and the world they are going to be growing up in.”
Britain’s Brexit malaise?
Time will tell whether the latest rush in support for the Greens, and other small parties such as UKIP, are a symptom of Britain’s Brexit malaise or whether they are a permanent fixture of the political landscape.
But, despite the Greens soon having to compete with Nigel Farage’s new Brexit Party and new kid on the block Change UK, Green Party deputy leader Amelia Womack is optimistic for the Euro elections.
In London, where local elections did not take place on Thursday, a YouGov poll earlier this month put the Greens on almost level pegging with the Conservatives, suggesting the party stands to make further gains.
Womack told HuffPost UK the Green surge in membership from the 2015 general election leaders’ debates has buoyed the party.
“We have seats in places we have never had them before,” she said. “This is an historic election for the Green Party and I am personally thrilled about our result. We have been growing year upon year upon year and we are building on strong foundations.
“Where we already have Green councillors, we have got more and that’s because we work hard.
“We are not just a flash in the pan.”