President Donald Trump's decision to pull out of the Paris climate accord has triggered a bipartisan push from U.S. mayors to stick to the emissions cuts Washington had pledged to hit, the mayor of Atlanta said Tuesday.

Dozens of city mayors from around the world -- including Washington, Berlin, Paris, Tokyo and Sydney -- on Monday called on G20 leaders to stick to their commitments on tackling climate change.

Hollywood star turned activist Arnold Schwarzenegger joined politicians and legal experts in Paris Saturday to launch a campaign for a global pact to protect the human right to a clean, healthy environment.

Former California governor Arnold Schwarzenegger urged people from both ends of the political spectrum to join a "crusade" to save the planet, after a Friday meeting with French President Emmanuel Macron.

France is to stop granting new licences for oil and gas exploration on the mainland and in overseas territories, Environment Minister Nicolas Hulot said Friday.

Scientists studying global warming recently climbed Bolivia's towering Mount Illimani and extracted samples of glacier ice packed with thousands of years of climate data.

The international ICE Memory project team braved low oxygen and bitter, ice-cold wind that whipped them mercilessly at an altitude of 6,300 meters to drill deep into the glacier and pull out two cylinders of ice.

In the azure waters of the Red Sea, Maoz Fine and his team dive to study what may be the planet's most unique coral: one that can survive global warming, at least for now.

The corals, striking in their red, orange and green colours, grow on tables some eight metres (26 feet) underwater, put there by the Israeli scientists to unlock their secrets to survival.

Coral reef bleaching may be easing after three years of high ocean temperatures, the longest such period since the 1980s, the National Oceanic and Atmospheric Administration said Monday.

The European Union on Monday blasted U.S. President Donald Trump for pulling out of the Paris climate change pact and said Brussels would continue to lead efforts to prevent global warming.

France has made good on its promise to invite foreign climate change experts to the country, pledging 30 million euros to fund the work of up to 50 researchers.