A day of worldwide protests against climate change is underway that organizers predict will draw more than one million participants, the largest-ever expected demonstration decrying the man-made causes of a warming planet.
Friday's protests began across Asia, where hundreds of thousands of students and others took to the streets calling for action against climate change ahead of a United Nations summit on the issue. The protests later spread to Africa and Europe, with huge crowds filling the streets.
In Australia alone, more than 300,000 children and adults rallied with the backing of some local authorities, schools and businesses. School Strike 4 Climate in Australia said the throngs of protestors represented the largest climate protest in the country's history. Warmer weather patterns have taken a toll on Australia, sparking drought, flooding, more intense brushfires and the whitening of the Great Barrier Reef.
Smaller protests occurred across Asia, from the Philippines to Hong Kong and India.
Rallies are also underway in the United States, where organizers say more than 800 events have been planned, including several high-profile demonstrations in New York. More than 1 million students in some 1,800 New York City public schools have been allowed to skip school in order to participate.
In Africa, protests were held in Nairobi, Kenya and in the South African cities of Johannesburg and Pretoria. Experts say Africa is the most vulnerable continent to climate change and the least equipped to deal with the phenomenon.
Swedish teenage activist Greta Thunberg helped inspire the protests, staging weekly demonstrations for the past year calling on world leaders to bolster efforts to combat climate change. Friday's Global Climate Strike is the third of several worldwide climate rallies organized by students and led by the 16-year-old Thunberg.
Thunberg is scheduled to speak at an emergency U.N. climate change summit on Monday, when Secretary-General Antonio Guterres is expected to urge world leaders to exceed their commitments to the 2015 Paris climate accord.
Guterres has demanded that countries present plans of direct action, including ending construction of coal-fired power plants and reducing fossil fuel subsidies.
Countries that are committed to the Paris agreement have pledged to limit the long-term rise in the Earth's average temperature to two degrees over pre-industrial levels.
A U.N. report to be released next week is expected to conclude that global warming and pollution are devastating oceans and polar regions, raising risks for ecological devastation around the world.
The Trump administration has cast doubt on a broad scientific consensus that the earth is warming and human activity is mostly to blame.