Congratulations, you've lived to see a planet transformed back to the Pliocene Epoch, at least in terms of greenhouse gas levels. "The window of opportunity for action is almost closed," says the UN's World Meteorological Organization after its annual assessment found concentrations of carbon dioxide in the atmosphere climbed 0.5% last year to record levels; those levels of carbon dioxide, and other greenhouse gases, are 41% higher than in 1990, per Bloomberg. That's a level last seen 3 million to 5 million years ago, when the global temperature was several degrees warmer and sea levels were up to 66 feet higher than today. "Without rapid cuts in CO2 and other greenhouse gases, climate change will have increasingly destructive and irreversible impacts on life on Earth," WMO Secretary-General Petteri Taalas says.
Contributing to violent weather events and the melting of ice caps, CO2 concentrations rose from an average of 403.3 parts per million in 2016 to 405.5 parts per million in 2017, reports New Scientist. Levels of methane, at 2.5 times the pre-industrial mark, and nitrous oxide, over 20% higher than the pre-industrial mark, also rose, per the Guardian, while WMO reported a resurgence of trichlorofluoromethane, a banned chemical tied to ozone depletion. "I am very concerned," a climate researcher tells the Guardian. "It seems the urgency and extent of the actions needed to address climate change have not sunk in." Per Bloomberg, the report will "add to pressure" on representatives from almost 200 countries who will meet to discuss climate change responses in Poland next month. (US policies could be making things worse.)