This is the warning launched today Michel Jarraud, WMO Secretary-General, in presenting the final report of that entity on the concentration of greenhouse gases in the atmosphere.
"It is a reality in today move into uncharted territory at a rate unprecedented and terrifying consequences," he said Jarraud told a news conference.
"It's uncharted territory because the concentrations of greenhouse gases today reached levels that have not existed on Earth for over 800,000 years ago and maybe even for more than a million years," he said.
"It is a situation that the human race has not experienced," he said.
The study reveals that, in 2014, the atmospheric concentration of CO2 -the main greenhouse gas long-term unemployment reached 397.7 parts per million (ppm).
In the same year, in the northern hemisphere, CO2 concentrations exceeded the symbolic value of 400 ppm in the spring, when the CO2 is the most abundant.
In the spring of 2015, the global average atmospheric concentration of CO2 also crossed the barrier of 400 ppm.
In fact, between 1990 and 2014 the greenhouse gases have caused 36 percent more heat energy in the atmosphere, contributing to global warming.
"The pace is packed, the curve is not linear but has accelerated, it is exponential. This is scary because the consequences and see, "said the scientist.
"The increased presence of greenhouse gases not only causes an increase in temperature, but also water changes, increased heat waves, floods in some parts of the planet and other extreme events," he said.
He argued that some of the extreme events that occurred in the recent past and can be attributed to climate change and recalled the case of Typhoon Haiyan, which caused more than 6,300 deaths and thousands missing in the Philippines in 2013.
"There can be attributed to climate change typhoon. But it was much higher in the Philippines because sea level has risen 35 centimeters longer and that contributed to the devastating effects of typhoon "he said.
Human activities such as burning fossil fuels, have altered the natural balance and by 2014 the global average concentration of CO2 reached 143% of the average in the preindustrial era.
The study warns that "it is likely that the global annual average exceeds 400 ppm in 2016".
The other greenhouse gases such as methane (CH4), and nitrous oxide (N20), also reached record levels in 2014.
Currently, atmospheric methane equivalent to 254% of its pre-industrial level and nitrous oxide to 121% of pre-industrial levels.
"Carbon dioxide remains in the atmosphere for hundreds of years in the ocean and much more. Past, present and future emissions will have a cumulative effect on both the warming and acidification of the oceans, "says the text.
Jarraud recalled that, three weeks before the summit begins in Paris on Climate Change (cop21), an event in which the international community aims to achieve an ambitious binding global pact to reduce emissions, the awareness of political actors is essential .
In fact, the Bureau of Meteorology said today the United Kingdom in 2015, for the first time, the surface temperature of the Earth will rise 1 degree Celsius compared to pre-industrial times.
In cop21 it is expected to agree to limit temperature increase to a maximum of 2 degrees in 2100.
"You have to limit climate change to a level that we can adapt, we can not avoid completely, but we can limit it, we can adapt to the most important consequences and avoid other, because we already have irreversible phenomena such as increasing the level of the sea, acidification and extreme events, "he said Jarraud.