With new evidence that the concentration of greenhouse gases broke yet another record in 2014, the head of the World Meteorological Organization (WMO) warned on Monday that the warming planet is hurtling “into uncharted territory at a frightening speed.”

The United Nations weather agency’s latest Greenhouse Gas Bulletin (pdf) reports that atmospheric concentrations of carbon dioxide (CO2) reached 397.7 parts per million (ppm) in 2014, substantially beyond the 350ppm level deemed “safe” by scientists to avoid global warming.

WMO Secretary-General Michel Jarraud said this means that we will “soon” be living with globally averaged CO2 levels above the dangerous milestone of 400 ppm “as a permanent reality.”

“We can’t see CO2. It is an invisible threat, but a very real one,” Jarraud said. “It means hotter global temperatures, more extreme weather events like heatwaves and floods, melting ice, rising sea levels, and increased acidity of the oceans. This is happening now and we are moving into uncharted territory at a frightening speed.”

The report further shows that concentrations of the most prevalent greenhouse gases reached new highs in 2014 with industrial, agricultural, and domestic activities driving dramatic increases since pre-industrial times. Carbon levels have increased 143 percent, nitrous oxide (N2O) is at 121 percent, and methane (CH4) reached an eye-popping 254 percent increase since 1750.