In the relatively few years, geologically speaking, since the 19th century, carbon dioxide levels in the atmosphere have risen from 280 to 363 parts per million, the highest level seen in 160,000 years, and these levels are continuing to rise.
近代二氧化碳含量則由十九世紀初的二百八十 PPMV，短時間內上升到目前的三百六十三 PPMV，是十六萬年來的最高值，數字仍在快速竄升中。