Climate change campaigners gathered in New York's Times Square on Earth Day to urge action on global warming and cuts in plastics use while volunteers worldwide planted trees and cleared trash to mark the 54th annual celebration of the environment.

Earth Day this year, officially April 22, followed weeks of extreme weather with temperatures soaring to record highs in Thailand and a punishing heat wave in India, where at least 13 people died of heatstroke at a ceremony last weekend.

Average global temperatures could hit all-time highs in 2023 or 2024, climate scientists have warned.