Prince William is visiting New York Tuesday during Climate Week, the climate summit that coincides with the United Nations General Assembly, to announce the finalists for the Earthshot Prize, his climate-focused charity. 

In his first trip to New York City in nearly a decade, William made several stops, including to a fire station near the World Trade Center, where he met with first responders to discuss the importance of mental health care. A day earlier, he harvested oysters with school kids in New York Harbor as part of the Billion Oyster Project, an organization dedicated to revitalizing oyster populations in the harbor. William also met with U.N. Secretary-General António Guterres on Monday to discuss climate change ahead of the summit.

He said at Tuesday's summit that he went for a run in Central Park that morning.

"I decided to join the hordes of New Yorkers doing their morning routine," William said.

Who are the finalists for the Earthshot Prize?

The 15 finalists for the 2023 Earthshot Prize include the following groups: 

• Coastal 500, a group of mayors of and local government leaders from eight different countries working to restore ocean habitats and advocating for coastal protection internationally; 
• WildAid Marine Programme, a global nonprofit based in the U.S. that addresses the world's ocean conservation needs; 
• Circ Inc., which created a solution to enable the recycling of polycotton fabrics, which make up half of all textile waste; 
• Aquacycl, which uses microbial technology to make the treatment of industrial wastewater more accessible, more efficient, and less polluting; and 
• Boomitra, which is removing emissions and boosting farmer profits by incentivizing land restoration through a verified carbon-credit marketplace.

Peter Majeranowski, CEO of Circ Inc., told CBS News' Meg Oliver that he was "super excited to represent the U.S.A."

"Textiles are one of the biggest polluters on the planet, and less than 1% is currently recycled back into textiles," he said.

Other finalists come from the United Kingdom, Peru, Brazil, Sierra Leone, Hong Kong, South Africa and Australia. 

The prize categories are: Protecting and Restoring Nature; Cleaning the Air; Reviving the Oceans; Building a Waste-Free World; and Fixing Our Climate.

The winners in the five categories will be announced next month in Singapore. Last year's ceremony was held in Boston. 

What is the Earthshot Prize?

In 2020, Prince William launched what Kensington Palace called "the most prestigious global environment prize in history," known as the Earthshot Prize. William said he was inspired by President John F. Kennedy's "Moonshot" pledge to get Americans on the moon.  

"It came about from a desire to see more change and to highlight wonderful people doing incredible things," he said Tuesday.

"I kept being shown these amazing things that were happening that I just felt the impact from them wasn't being achieved, or the potential wasn't there when it could be," he said. "So, I was thinking, 'How do we elevate?' How do we scale this up? How do we allow more people to see this?'"

William's father, King Charles III, has long championed environmental issues. 

Every year from 2021 until 2030, the Earthshot Prize Council will award a prize to five winners offering "evidence-based solutions" for each of the five broad Earthshot objectives:

• Protect and restore nature
• Clean our air
• Revive our oceans
• Build a waste-free world
• Fix our climate

According to Kensington Palace, each of the five annual winners will receive a reward of about $1.3 million, "that will be used to support agreed environmental and conservation projects as well as large-scale public recognition and significant support to scale their solution."

"Ten years down the line, when we look back, I want to make sure we've found the right solutions, we've found the right people, but we're also maximizing their impact," William said.

Watch the story of one of the 2022 winners, on a mission to replace single-use plastic with seaweed, in the video below:

— Charlie D'Agata contributed to this report. 

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• Prince William Duke of Cambridge
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