Thousands of students across Indonesia have staged days of demonstrations protesting the government's response to toxic haze that has blanketed multiple cities and spread to other nations in Southeast Asia in recent weeks.

On Friday, more than 500 protesters gathered in front of the Central Kalimantan Governor's Office in the provincial capital of Palangkaraya, demanding more action to address the haze. Protests earlier this week spread to more than half a dozen Indonesian cities, including on the island of Borneo, where many of the fires are actively burning.

High winds knocked out power to thousands of people in southwest England on Friday morning as the first of two major storms expected to hit the U.K. this weekend swept in from the Atlantic.

The U.K. Met Office issued an amber warning — the second highest — for wind gusts up to 80 mph (130 kph) in Cornwall and Devon as the storm named Austen by the agency moved into the area early Friday.

While Brazil's presidential candidates have not made policy of the Amazon a major campaign topic, climate scientists and environmentalists say the winner of Sunday's race could determine whether, and how soon, the world's largest rainforest could reach a "tipping point."

The key threshold, heavily debated among scientists, in simple terms would be when the dense, humid, moisture-generating forest shifts to a drier ecosystem. That would come with irreversible consequences for biodiversity and the climate, as the forest absorbs massive amounts of carbon dioxide, a greenhouse gas that drives global temperature to rise. Brazil contains about 60% of the Amazon, which is spread across several countries in South America.

Taiwan shut down schools and offices and grounded hundreds of flights as Typhoon Champi brushed by the island Friday, packing strong winds and torrential rains.

Champi peaked at 298 kph (185 mph) maximum sustained winds earlier this week but has weakened to 155 kph (96 mph) winds as it approached Taiwan from the southwest. Its center is forecast to remain offshore as it sweeps by the island's northeastern tip before turning north toward Japan's southwestern islands.

The world's coral reef ecosystems almost all face a high risk of collapse in the next 50 years mostly due to warming oceans and heat waves, according to a global assessment released Thursday.

The International Union for Conservation of Nature's assessment, announced on the sidelines of a U.N. biodiversity conference in Albania, found that 96% of shallow-water reef systems are already critically endangered and could disappear by 2075.

Trees fell onto homes and utility poles were knocked down by a possible tornado in a central Arizona community during a series of violent storms that moved through the state overnight into Thursday.

Storms capable of causing hail and wind damage were traveling through central Arizona early Thursday, with some flood watches and the possibility of tornadoes, the National Weather Service said.

Losing more ground in the fight against climate change, humanity is heading for a hotter world than experts projected last year — and the United States is a big reason for that, a new United Nations report says.

If all the countries do what they promise to reduce heat-trapping emissions, Earth will likely still warm another 2.2 degrees Fahrenheit (1.2 degrees Celsius) above current temperatures, according to Wednesday's update of climate calculations by the United Nations Environment Programme. That's about two-tenths of a degree Fahrenheit (0.1 degrees Celsius) more than last year's projections by the same science team.

The El Nino weather phenomenon gripping the planet could be off the charts, the United Nations warned Wednesday, saying countries should take urgent action to prepare for the worst.

Indonesians protested in several cities on Tuesday, raging against wildfires and a toxic haze that has made thousands unwell for weeks on end in a crisis that has engulfed Southeast Asia.

Demonstrations were called by students to display dissatisfaction with the government of President Prabowo Subianto, which marked its second year on Tuesday.

Britain's Met Office says this year's El Nino is "unprecedented." Japan's weather agency has called it the strongest ever observed. U.S. forecasters say it still trails the biggest events in its record books.