UN negotiations on implementing the Paris climate change agreement wrap up Friday after two weeks of talks that were slowed down by the United States defending the use of fossil fuels.

Floods caused by two days of torrential rains have left five people dead in Haiti and more than 10,000 homes inundated, authorities said Thursday.

The toxic smog that has covered parts of Pakistan for weeks has exposed official torpor over rampant pollution that has killed thousands more people than have died in years of militancy.

The echo of Koranic verse from a religious school in Senegal's Saint-Louis is familiar, but just metres down the beach classes have fallen silent in another building abandoned to the ravages of climate change.

In the northern Indian city of Moradabad fumes from burning electronic waste blend with seasonal smog to create an even deadlier mix of pollutants than in Delhi, where filthy air has caused public outcry and made global headlines.

India's smog crisis has centred on the capital but pollution is as bad or worse beyond its borders, with millions in smaller cities like Moradabad barely aware of the harmful effects of the air they breathe.

Climate change imperils one in four natural World Heritage sites, including coral reefs, glaciers, and wetlands -- nearly double the number from just three years ago, a report said Monday.

Air pollution in New Delhi worsened again Sunday and officials warned of little relief in sight from the smog, which has even caused one airline to cancel flights to the world's most polluted capital.

The world must sharply draw down greenhouse gas emissions and suck billions of tonnes of carbon dioxide from the air if today's youth are to be spared climate cataclysm, a top scientist has warned.

As thick smog crept over India's capital this past week and smudged landmarks from view, Nikunj Pandey could feel his eyes and throat burning.

Pandey stopped doing his regular workouts and said he felt tightness in his lungs. He started wearing a triple layer of pollution masks over his mouth. And he became angry that he couldn't safely breathe the air.

The failure of wealthy nations to deliver on short-term climate commitments could hinder the rollout of a landmark treaty, a bloc of 134 developing countries, including India and China, warned at UN negotiations in Bonn.