Prince William launched the Earthshot Prize so he could look his “children in the eye” and say he “did [his] bit” in the fight against climate change, a close aide has said.

Ahead of the 15 finalists for the environmental prize being announced later today, the Duke of Cambridge has revealed why he felt he needed to make a personal contribution to “the most pressing challenge of our time”.

In the introduction to a book about the Earthshot Prize the prince describes how a “wave of global pessimism” meant he felt he had to act.

He explains how in 2018 he witnessed incredible conservation work in Namibia but as he returned home was struck by the constant negative headlines around the climate debate.

“The rich wildlife that I saw thriving on that visit struck a real chord,” he writes.

“But when I returned to the UK, just as the world was gathering again for the next round of climate change negotiations in Poland, I was hit by a wave of global pessimism.

“The headlines were dominated by a sense that world leaders were not moving fast enough.

“There was widespread finger-pointing and political and geographical division.”

He writes that the global conversation surrounding the issue “felt too complex, too negative, too overwhelming”, adding that he realised there was a “real risk that people would switch off”.

Since 2018, William has worked with his closest advisors on a concept that would inject enthusiasm and optimism into the discussion.

The Earthshot Prize was designed to mirror the “Moonshot” challenge launched by former President J F Kennedy and inspire a new generation to come up with innovative and creative solutions to address the challenges facing the planet today.

Speaking about the duke’s commitment to the project Jason Knauf, CEO of The Royal Foundation, said: “The challenge the duke set himself was ‘what is the maximum positive personal contribution I can make in the next ten years in the fight against climate change?

“‘What am I going to do in the next decade that means I can look my children in the eye and say I did my bit?’ Every aspect of the prize bears the stamp of his contribution.”

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The first Earthshot Prize ceremony will be held in London on the 17 October, when the five winners will be revealed.

Some 750 nominations were submitted from 86 countries “exceeding the expectations” of those involved in the prize.

The winners receive £1m each, but all the finalists will get the backing of the Earthshot Prize Global Alliance Members – businesses and organisations that will help to support, promote and scale up their ideas.

The prize will run every year until the end of the decade, with a total £50m prize fund.

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