This photo taken on March 25, 2023 shows the Petronas Twin Towers before the Earth Hour event in Kuala Lumpur, Malaysia. Earth Hour is a worldwide movement organized by the World Wildlife Fund. The event is held annually, encouraging individuals, communities, and businesses to turn off non-essential electric lights, for one hour, from 8:30 p.m. to 9:30 p.m. on the Saturday of March, as a symbol of commitment to the planet. (Photo by Chong Voon Chung/Xinhua)

The Petronas Twin Towers go dark during the Earth Hour event in Kuala Lumpur, Malaysia, March 25, 2023. Earth Hour is a worldwide movement organized by the World Wildlife Fund. The event is held annually, encouraging individuals, communities, and businesses to turn off non-essential electric lights, for one hour, from 8:30 p.m. to 9:30 p.m. on the Saturday of March, as a symbol of commitment to the planet. (Photo by Chong Voon Chung/Xinhua)

The Quezon Memorial Shrine goes dark during the Earth Hour event in Quezon City, the Philippines, March 25, 2023. Earth Hour is a worldwide movement organized by the World Wildlife Fund. The event is held annually, encouraging individuals, communities, and businesses to turn off non-essential electric lights, for one hour, from 8:30 p.m. to 9:30 p.m. on the Saturday of March, as a symbol of commitment to the planet. (Xinhua/Rouelle Umali)

The Sydney Opera House goes dark during the Earth Hour event in Sydney, Australia, March 25, 2023. Photo:Xinhua