1. Global warming and greenhouse gas emissions

The first volume on the physical elements of climate, of the IPCC's 5th report, was published in September 2013. In this report, the involvement of human activities on the CO ₂ content of the atmosphere and recent climate evolution is confirmed. This is in addition to two other factors, namely climate response to natural factors (solar activity, volcanic activity) and internal climate variability (ocean-atmosphere interactions). However, it is mentioned that it is extremely likely that human influence is the dominant cause of observed climate change.