Twelve years. According to climate scientists, that’s how long until we hit the 1.5C tipping point if we carry on as we are.

Such a shift in our planetary temperature will imperil not only low-lying areas because of the increased risk of floods, but will have consequences for all of us – not least due to the necessary migration of millions of people away from areas that become uninhabitable.

Coral reefs will vanish; many ancient trees will not survive; extreme weather events will become ever more common. The Intergovernmental Panel on Climate Change paints a bleak picture.

10 photographs to show to anyone who doesn't believe in climate change Show all 10 1 /10 10 photographs to show to anyone who doesn't believe in climate change 10 photographs to show to anyone who doesn't believe in climate change A group of emperor penguins face a crack in the sea ice, near McMurdo Station, Antarctica Kira Morris 10 photographs to show to anyone who doesn't believe in climate change Floods destroyed eight bridges and ruined crops such as wheat, maize and peas in the Karimabad valley in northern Pakistan, a mountainous region with many glaciers. In many parts of the world, glaciers have been in retreat, creating dangerously large lakes that can cause devastating flooding when the banks break. Climate change can also increase rainfall in some areas, while bringing drought to others. Hira Ali 10 photographs to show to anyone who doesn't believe in climate change Smoke – filled with the carbon that is driving climate change – drifts across a field in Colombia. Sandra Rondon 10 photographs to show to anyone who doesn't believe in climate change Amid a flood in Islampur, Jamalpur, Bangladesh, a woman on a raft searches for somewhere dry to take shelter. Bangladesh is one of the most vulnerable places in the world to sea level rise, which is expected to make tens of millions of people homeless by 2050. Probal Rashid 10 photographs to show to anyone who doesn't believe in climate change Sindh province in Pakistan has experienced a grim mix of two consequences of climate change. “Because of climate change either we have floods or not enough water to irrigate our crop and feed our animals,” says the photographer. “Picture clearly indicates that the extreme drought makes wide cracks in clay. Crops are very difficult to grow.” Rizwan Dharejo 10 photographs to show to anyone who doesn't believe in climate change Hanna Petursdottir examines a cave inside the Svinafellsjokull glacier in Iceland, which she said had been growing rapidly. Since 2000, the size of glaciers on Iceland has reduced by 12 per cent. Tom Schifanella 10 photographs to show to anyone who doesn't believe in climate change A river once flowed along the depression in the dry earth of this part of Bangladesh, but it has disappeared amid rising temperatures. Abrar Hossain 10 photographs to show to anyone who doesn't believe in climate change A shepherd moves his herd as he looks for green pasture near the village of Sirohi in Rajasthan, northern India. The region has been badly affected by heatwaves and drought, making local people nervous about further predicted increases in temperature. Riddhima Singh Bhati 10 photographs to show to anyone who doesn't believe in climate change A factory in China is shrouded by a haze of air pollution. The World Health Organisation has warned such pollution, much of which is from the fossil fuels that cause climate change, is a “public health emergency”. Leung Ka Wa 10 photographs to show to anyone who doesn't believe in climate change Water levels in reservoirs, like this one in Gers, France, have been getting perilously low in areas across the world affected by drought, forcing authorities to introduce water restrictions. Mahtuf Ikhsan

Yet the scientists are also clear that we can still hold the line on further damaging change – if we’re prepared to act fast and invest a great deal of money. By reducing CO2 emissions by nearly half from their 2010 levels, we could give ourselves a fighting chance; by planting millions of trees and using technology to further capture carbon dioxide too, we might just do it.

But in all honesty it is hard to feel optimistic about the world’s ability to make that happen. The World Wildlife Fund’s lead climate change scientist, Chris Weber, says “the difference between possibility and impossibility is political will”, which in present circumstances is unnerving, to say the least.

For one thing, the world’s most powerful politician is arguably its most famous climate change sceptic. According to Donald Trump, “the concept of global warming was created by and for the Chinese in order to make US manufacturing non-competitive”. Sure enough, he backed up such Twitter trash-talk by pulling America out of the Paris climate agreement soon after taking up residence in the White House.

Meanwhile, in China – the world’s biggest greenhouse gas emitter by a distance – the amount of carbon being thrown into the atmosphere is increasing: emissions rose by 4 per cent in the first three months of 2018. As it goes, the Chinese have invested significantly in renewables, yet the growing prosperity of its vast population continues to increase demand for energy to such an extent that curbing carbon output is challenging, to say the least. India’s CO2 emissions are also soaring – albeit from a much lower base, which means there is a glimmer of hope on the subcontinent for a greener future.

Even at the individual level, though – and even among those who accept that climate change is a real and present danger – is there really the will to change our ways for good? We might be more likely to consider a car’s carbon emissions when we choose a new motor; but are we really much less inclined to drive the short distance to the shops when there’s a bit of rain in the air?

Likewise, we might be shocked when we see a show on TV like last week’s Drowning in Plastic – which revealed the amount of plastic being swallowed by seabirds, among other horrors – but can we maintain the hastily made resolution never again to buy plastic tat for the kids when they’re whining their way round the supermarket?

Those who deny climate change remain peculiarly certain that all will be well. And in light of Trump’s attitude, China’s demographic reality, as well as our own human weakness, there is a temptation to throw up our hands and give it all up to fate.

But of course we mustn’t. After all, even if there was a modest chance that the vast majority of climate scientists and policymakers were right in their conclusions about the way we are changing our planet – and about the likely consequences – then it would seem sensible to act in a way that might reduce the level of harm we are doing to the planet (frankly, it would seem bonkers to do otherwise). That means making myriad small changes to our lives; and it means pressuring politicians to pursue green policies.