Annual switching off of lights in homes, businesses and landmarks holds extra significance ahead of this year’s climate talks in Paris, says the UN secretary general, Ban Ki-moon
Fall in amount of carbon absored by rainforest means even greater cuts to manmade emissions are needed to combat climate change, warn scientists
A new study estimates the costs of energy sources including their carbon and other air pollutants
A luxury holiday company is offering to use geo-engineering to guarantee ‘fair weather and clear skies’ – for a starting price tag of £100,000
The $43.5bn trust is the largest philanthropic organisation in the world and is committed to the eradication of malaria and polio, and controlling the spread of tuberculosis and HIV
Manmade warming in past decade has likely been offset by cooling from natural cycles in the Pacific and Atlantic – but effect will reverse in coming decades