This year the Earth's climate scored the global warming trifecta: it passed the milestone of 1°C of warming since pre-industrial times; it is set to be the hottest year on record; and it will be the first year in which the concentration of carbon dioxide in the atmosphere is over 400 parts per million (ppm) on average due to the continued burning of fossil fuels.
This is uncharted territory for the Earth. It came as world leaders met in Paris for Climate talks on how to keep warming below 2°C.