Queen Elizabeth II, an advocate for climate action, dies at 96

The Royal Family announced that Queen Elizabeth II, 96, passed away peacefully at Balmoral Castle in Scotland on Thursday afternoon.

The queen, who had been frail in recent weeks, reigned for 70 years, Britain's longest reigning monarch, surpassing Queen Victoria's time on the throne of 63 years and seven months. She died with many royal family members at her side, media outlets reported.

In 2021, the queen made headlines as she urged for bold climate action in a video message at the United Nations Climate Change Conference in Glasgow (COP26).

The monarch had originally been scheduled to attend the UN conference, but after medical checks, she was instead advised to rest.

In place of attending the conference, she pre-recorded her address in the week ahead at Windsor Castle, urging world leaders to "achieve true statesmanship." She reiterated the dire need to create a "safer, stabler future" for the planet and "for our children and our children's children."

"The time for words has now moved to the time for action," she said.

A picture and quotation taken from Britain's Queen Elizabeth II's address to COP26 delegates as she appears as a domination on the Piccadilly Lights, at Piccadilly Circus in London, Wednesday, Nov. 3, 2021. (AP Photo/Kirsty Wigglesworth)

Ahead of the conference, a video of a conversation between the queen; her daughter-in-law Camilla, the Duchess of Cornwall; and Welsh official Elin Jones at the opening of the Senedd recorded the queen appearing to express frustration around climate policy and inaction from world leaders.

The conversation had been picked up by the event's live stream cameras but hadn't been meant for the public, according to the Daily Mail. "I've been hearing all about COP ... I still don't know who's coming," she appeared to be saying.

In another clip, she was reported to say, "We only know about people who are not coming ... It's really irritating when they talk, but they don't do."

China's Xi Jinping, Russia's Vladimir Putin, Brazil's Jair Bolsonaro and Turkey's Recep Tayyip Erdogan did not attend the summit.

The COP26 conference is seen as a crucial gathering to discuss and review how countries manage climate change.

The queen paid tribute in her speech to young climate activists, saying she had "drawn great comfort and inspiration from the relentless enthusiasm of people of all ages - especially the young - in calling for everyone to play their part." At the time, climate activists led by Greta Thunberg had been demonstrating in Glasgow during the conference.

She added how the environment was a subject close to the heart of her late husband, Prince Philip, and she couldn't be more proud that it was an area of interest picked up by her son Charles and grandson William.

The Queen's Green Canopy (QGC) was created in 2022 to mark the queen's Platinum Jubilee, which celebrated her 70 years on the throne. The QGC invited people across the United Kingdom to "plant a tree for the Jubilee," with a focus on planting sustainably, and pledged to dedicate a network of 70 Ancient Woodlands across the U.K. and identify 70 Ancient Trees.

"The death of my beloved Mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family," Prince Charles said in a statement Thursday.

Charles, who will now be known as King Charles III, will succeed the queen.

As hundreds of mourners gathered outside of Buckingham Palace in London Thursday, a sparkling double rainbow appeared in the sky.

A man looks on holding a Union flag umbrella as a double rainbow is seen outside of Buckingham Palace on Sept. 8, 2022, in London, England. (Photo by Samir Hussein/WireImage)