Global warming and climate change both refer to the observed century-scale rise in the average temperature of the Earth's climate system and its related effects. More than 90% of the additional energy stored in the climate system since 1970 has gone into ocean warming; the remainder has melted ice, and warmed the continents and atmosphere.The observed increases in global average surface temperature and atmospheric carbon dioxide have been much faster in recent decades than the natural changes of previous millennia, and levels are now higher than at any time for hundreds of thousands of years prior.