The concentration of carbon dioxide (CO2) in the atmosphere averaged a record 400 parts per million in 2015, an ominous milestone for the planet's health, the U.N. said Monday. 

Hollywood star Mark Ruffalo accused US President Barack Obama on Sunday of hypocrisy for allowing fracking and other fossil fuel extraction while presenting himself as a green president.

The Oscar-nominated "Spotlight" and "Avengers" actor spoke out at a rally in Los Angeles protesting against man-made climate change and, in particular, the controversial Dakota Access Pipeline, the site of escalating protests in recent weeks.

Hungry Philippine typhoon survivors huddled in makeshift shelters and waited for aid on Friday, after losing nearly everything from one of the most powerful storms to hit the Southeast Asian archipelago.

Super Typhoon Haima struck on Wednesday night with winds similar to those of catastrophic Haiyan in 2013, which was then the strongest storm to hit the disaster-prone country and claimed more than 7,350 lives.

More than a thousand stray dogs have been poisoned to death by municipal workers in Karachi after a deluge of complaints about animals biting women and children, an official said Wednesday.

The United Nations has urged Bangladesh to halt construction of a huge coal-fired power plant near the Sundarbans, warning of a serious threat to the delicate ecosystem of the world's largest mangrove forest.

Rich countries, which have pledged $100 billion (91 billion euros) every year from 2020 for poor countries to deal with climate change, said Monday they were "confident" of meeting the target.

Three Indonesian men have been arrested for allegedly trading in protected species, with police seizing animal parts including a tiger skin, deer genitalia and pangolin scales, an official said Monday.

A striking bird with monochrome plumage and a formidable "beak", the helmeted hornbill is being hunted to extinction, one of the latest victims of a thriving global trade in exotic wildlife.

The Philippines faces what could be "the most damaging" storm this year as Typhoon Sarika headed for the archipelago's heavily-populated main island, officials said Saturday.

World envoys reached an agreement Saturday on a timetable for the phase-out of potent greenhouse gases used in refrigerators and air conditioners, a major step in curbing global warming.

The amendment to the 1987 Montreal Protocol on protecting the ozone layer was greeted by applause from exhausted envoys who had worked through the night in the Rwandan capital Kigali to put the final touches on the deal to phase out production and consumption of hydrofluorocarbons (HFCs).