"Join us! JOIN US!" cried a teenage boy as he led a procession of schoolchildren towards the Houses of Parliament from the statue of Nelson Mandela in Westminster Square. Behind him, I was speaking to a girl holding an "Unfuck the Planet" sign – one of the thousands of attendees at the UK's first "School Strike for Climate" march in February.

"They care about missed school days," she said of the politicians and commentators criticising the kids who had skipped school to attend the protest. "I don't even know what they're educating us for if they don't do something about the actual fucking Earth."

Scenes like these would play out again and again in the following months, as thousands of children inspired by the 16-year-old Swedish climate campaigner Greta Thunberg missed school one Friday every month to protest government inaction on the climate crisis.

Since then, the indifference referenced by the young woman I spoke to has seemingly turned into at least surface level concern. Britain's government has declared a climate emergency, as has Ireland's. Those gestures are fairly meaningless until politicians start to work on concrete policy changes, but they do at least signal that public anxiety around environmental collapse is starting to be heard by those in the houses of power. Which is reassuring, because that anxiety is on the up.

Protesters at the first UK school strike. Photo: Chris Bethell

According to a number of therapists I spoke to for this article, the climate crisis is becoming a primary trigger for anxiety and depression among patients, while a 2017 report from the American Psychological Association detailed the rise of "eco-anxiety". This increase in environment-related mental health issues undoubtedly has something to do with the fact the environment is so much more a part of the cultural conversation than it was even three years ago.

"Deep Adaptation" – Professor Jem Bendell's controversial apocalyptic climate change paper, which VICE covered recently – is now a topic of dinner party chat. In France, where the Gilets Jaunes movement kicked off because of a supposedly environmentally-friendly measure, the term la collapsologie (the collapse of industrial civilisation) has been used not only by activists, but also by Emmanuel Macron's government. Groups in the US and UK hold mourning sessions for the planet. And as the school strikes have shown, children across the world are keenly aware of the bleak future that awaits them if drastic action is not taken soon.

Michael Lynas is the CEO of NCS, a personal development programme for teenagers. "We don't tell them to do this or that – they find things to care about," he explains of the programme. "And the two biggest issues are mental health and the environment."

Nikita Rokotyan was part of a team that was awarded the World Data Visualisation Prize 2019 for its work on climate change modelling, using machine learning to establish the patterns of the ongoing collapse. "Our world is becoming more unpredictable," Nikita told me. "You cannot look at this material and not be influenced. And by only looking at the big picture, we are missing the small things that are already happening everywhere."

By way of example, Rokotyan uses a story from his home country, Russia: "I was talking with this guy who owns a big factory in Siberia that produces cedar nuts. If there's an extreme event – if it becomes too cold for just one day in May – then you have [no nuts]. They used to be able to predict how much production they could expect, [but now they can't]. It's too unpredictable. And that is what affects people: this constant change, not knowing what will happen tomorrow."

Sholeh Johnston works as a life-coach in London. She has witnessed firsthand the psychological toll of the uncertainty caused by better awareness of the climate crisis. "There is a sense of loneliness [among clients], of feeling like they don't have a community with whom they are working through the difficult emotions that are coming up," she tells me. "There's a real sense of grief and loss of seeing what's happening. Loss of biodiversity. Loss of land. Loss of the ability to see in the long-term that they can have relationships with loved ones who live abroad […] Emotions like fear."

Johnston's experience also proves this obviously isn't an issue restricted to the white middle-class, as some critical of recent climate activism have argued. "Having worked with and mentored particularly people of colour or people from more marginalised backgrounds," she says, "I've seen this really deep and unresolved sense of trauma about the roots of why we're in the mess we're in with climate change, the effects of colonialism and being connected to parts of the world that are directly suffering – on the front line of climate change already and for a while now."

In his best-seller The Uninhabitable Earth, David Wallace-Wells says, "Between a quarter and a half of all those exposed to extreme weather events will experience them as an ongoing negative shock to their mental health. In England, flooding was found to quadruple levels of psychological distress, even among those in an inundated community but not personally affected by the flooding." Citing a study published in The Lancet, he adds: "Rising temperature and humidity are married, in the data, to emergency-room visits for mental health issues."

"I see younger people more able to express a sense of deep anxiety and emergency because they’re in a moment in their lives where they're thinking: 'Okay, so how do I put my life together,'" says Sholeh Johnston. "And when they look out and see the reality of where we're headed in terms of climate change – and the economy – it becomes really difficult to think: 'Well, what am I going to do with my life?' And the sources of support for actually thinking practically about that are not widespread and they're not very accessible."

A counter-protester and a protester at Extinction Rebellion's London demonstration. Photo: Chris Bethell

The question of how we talk about and come to terms with these issues led me to a workshop in north London organised by the Climate Psychology Alliance, where Jem Bendell and the psychotherapist and veteran climate campaigner Ro Randall were the main speakers. Several members of the protest group Extinction Rebellion were in attendance, their logo visible on pins, badges and stickers.

"People," said Randall during her talk, "they clock every news development and torture themselves with it." This tendency, she said, fills people with dread: "In order to expunge some of this, you start punishing others." She described anger and lashing out at each other as a last ditch attempt to re-assert control over our lives when everything around us is changing.

Bendell agreed: "In the last month I've been getting angry responses, whereas before I wasn't."

Later on in the day, we moved into a more intimate discussion.

Eleanor*, a young single mum and activist, talked about the ferocious energy she sees in the other mothers she meets at climate marches. She said she's in awe of them, but also terrified, as these are the women she might have to physically fight over the last loaf of bread after the inevitable collapse of society. I confessed that similar thoughts come to mind every time I see some new story about us inching closer towards a total environmental catastrophe. Someone else said that, in the 1980s, she bought a bottle of pills – enough to kill herself and her daughters. Back then, it was nuclear war she feared. The bottle is still there, but it's environmental collapse that worries her now.

When we think about the climate crisis, attendees agreed, we have three primary reactions: fear, grief and the feeling of a loss of control. Ro Randall dubbed these "infantile experiences" – not in a patronising way, but to describe the fact we're confronting the realities of our world for the very first time.

After the workshop, conversations about the future led to tears, but not necessarily tears of sadness or defeat. There was a tangible sense of catharsis in the air; the idea that no one is alone in their fears, and that – with the right approach – those concerns can act as fuel for activism.

Later, I walked with Bendell from the venue to his hotel. "It's difficult for people to realise what's going on through their everyday lives," he said. "Look around. Especially for those of us living in the big cities, we see normality. If we stand over there, at that stop, the bus will arrive in five minutes. The trash will be picked up. Supermarkets are stocked with food. But this can't be so for long. We are expecting a breadbasket crisis that will affect most of the world's food supply in the next decade. And none of us are getting ready for this."

I remarked that, in London and many other major cities across the world, young people are marching and protesting. "Okay," he replied. "Marching up and down and shouting and having some placards and calling on the government to act may help them a bit. But it's not the end of the story. We have to support them. To enable them to help themselves."

Bendell sees regaining a sense of community as pivotal to this process. "Maybe schools will become the centrepiece of our communities," he said. "The church has fallen away from most people’s lives, youth centres are being shut down, trade unions don't have the same power… maybe this movement could be the rallying point for a new sense of community. I think schools, being the place where parents still come together, could play a big role in whatever is ahead. And I'd like to see our education system being more honest about what's coming, and teaching children stuff that will be most definitely useful in the scenarios we are anticipating."

Among my cohort – millennials in their thirties – there's a tendency to take a nihilistic view of the climate crisis. To end a conversation about environmental collapse with, "Yeah, we're all fucked." Because it very much feels like we are, because politicians are still refusing to enact the structural changes needed to slow down the heating of the planet. But perhaps we can hold out some hope – look to the millions of teenage climate protesters around the world, see that they have already prompted a couple of governments to declare a climate emergency and keep our fingers crossed that others first follow suit, and then actually do something about it.

"The reason I'm optimistic," said Michael Lynas of NCS, "is because I think young people are not just lying down and taking it – they're active. Even ten years ago, the meme was that young people were apathetic and didn't care. If that was true at all, it's not true at all now."