How global temperatures have risen since 1884
20 September 2013 Last updated at 18:10 BST
Scientists and government officials are meeting in Stockholm this week to finalise the next report from the Intergovernmental Panel on Climate Change (IPCC).
The Summary for Policymakers that will be published on Friday will give us the clearest view yet on the state of climate science.
The report will detail the historic changes in global average temperatures, as in this video from Nasa, and make predictions for the scale of warming for the rest of this century.