The day of publication of the fifth climate report by the Intergovernmental Panel on Climate Change (Ipcc) has arrived. The document comes six years after the previous edition and puts all discussion on the subject to rest, setting the seal on the only truth that really matters: global warming is an "unequivocal" phenomenon, as declared by Rajendra Pachauri, head of the Ipcc, at the press conference held in Stockholm on 27 September. It is scientifically proven that the global average temperature is rising and the climate is changing due to the increase in CO2 emitted into the atmosphere by humans.

The data in the fifth report, Fifth Assessment Report (AR5) The report published today is the first of three and is the one that lays the scientific foundations of climate change. It is the most sensitive, as it is scrupulously scrutinised by sceptics who question the group's work. Since 2007, 9,200 scientific publications have been consulted, approximately two thirds of the total. The main data are as follows:

• The global average temperature has risen by 0.85 degrees between 1880 and 2012. The decade 2000–2010 was the warmest since records began. Between 1983 and 2012, the northern hemisphere experienced its thirty warmest years in the past 1,400 years. The slowdown of the past 15 years does not affect the overall long-term picture

• A temperature rise of more than 2 degrees Celsius is very likely by the end of the century

• 2 degrees Celsius is the threshold beyond which scientists argue that climate change will be irreversible. To keep the rise within this threshold, total emissions must be contained within one thousand gigatonnes of CO2, ideally around 800–880 gigatonnes. 54 per cent has already been emitted (equivalent to 531 gigatonnes), meaning we can emit a further 350

• The concentration of CO2 in the atmosphere has not been this high in 800,000 years. In 2013 it reached 400 ppm. A 40 per cent increase since the pre-industrial era, caused above all by fossil fuels. The oceans have so far absorbed 30 per cent of human-produced emissions, and this has led to their progressive acidification

• Sea level rise amounted to 0.19 metres between 1901 and 2010. It will rise further, by an additional 26 to 82 centimetres, by 2100 according to all models analysed

• Over the past two decades, glacier melting has affected Greenland and Antarctica. Snow cover in the Arctic Circle has also diminished and will continue to diminish throughout this century

What is the Ipcc, the Intergovernmental Panel on Climate Change The Ipcc is an intergovernmental panel of experts on climate change created in 1988 by the United Nations to study the phenomenon from a scientific standpoint and provide technical advice to governments on how to curb it. This year 831 scientists took part, while delegates from 195 countries attended the final session, held in Stockholm from 23 September. The Ipcc is made up of three working groups. The first group deals with the physical science; the second deals with the impact of global warming on life on Earth and possible forms of natural adaptation; the third provides advice on how to cut CO2 emissions (mitigation). In the course of its history, the Ipcc has published four other reports in addition to this one: in 1990, 1995, 2001 and 2007.

What changes from now on Climate models have improved compared to the fourth report, as they reproduce global average temperature trends on a continental scale over several decades. The new data are what the new international climate agreement — to be adopted at the Unfccc conference (Cop 21) to be held in Paris in 2015 — must now be built upon. To avoid arriving, as has often happened in recent years, without an agreed draft document and to prevent that conference's proceedings from running on for days beyond the deadline, United Nations Secretary-General Ban Ki-moon has already called for the convening of an extraordinary summit with heads of state and government to define the main points.