A boy with Asperger's will wear a green jumper on his first day at secondary school on Wednesday - even though his new uniform is blue.

Archie Hopkinson, aged 11, will protest to the government that they need to take urgent action to tackle the climate emergency when he starts at The Roseland Academy.

The Year 7 pupil said: "I want other children to know the climate crisis is getting out of control. If we all join in and all wear green, we might be able to persuade the government to act upon this crisis."

Over the summer holidays he has been anxious about his protest: he knew he might get detentions or be bullied. But he was determined to ‘be brave’. He added: "I want to do what is right. Not what is popular.

"If we carry on emitting carbon dioxide by burning coal and petrol the climate will get steadily warmer and melt the polar ice caps increasing water levels by one metre.

"This increase in sea levels would flood many low-lying countries. The people would have to be evacuated and their livelihoods would be severely damaged, and the wildlife would be completely wiped out."

Living in Cornwall means Archie is particularly conscious of the impact climate change is having on marine habitats. "The majority of species of coral, including those on the Great Barrier Reef, can only survive in a certain range of temperatures and the climate is predicted to rise by the end of the century by two more degrees. This is too hot for most of those corals and they eject algae that produces their food.

"This causes them to bleach. If they carry on bleaching, they will die. The coral reefs are a bit like underwater rainforests because they are very biodiverse like a big underwater city for wildlife. Scientists predict that by the end of the century there will be no more coral reefs on the planet. Imagine what we are robbing our descendants of seeing."

Aaron Kiely, climate campaigner at Friends of the Earth, said: "Archie is a hero; hugely courageous in bringing attention to the worsening climate crisis. His activism is sending a clear message to those adults who are supposed to provide proper leadership and leave the planet in a healthy state for the next generation.

"It’s time for businesses and politicians to listen to the voices of people everywhere, who are demanding proper action to stop the climate crisis getting any worse. We’re delighted to have Archie onboard as an activist, and look forward to launching our Planet Protectors club this September to help even more young people join the fight for our planet."

Through wearing green, Archie hopes to send a clear message to the government that time is running out to tackle the climate crisis.

He added: "There is no plan B. We can't all get into a spaceship and just leave planet earth to its unnecessary fate."