>>The World Meteorological Organization (WMO) has released a new report, the Greenhouse Gas Bulletin, and as you might expect the news isn’t great. In 2018, the globally-averaged concentration of carbon dioxide (CO2) in the atmosphere was 407.8 parts per million (ppm), a new record high that hasn’t been seen in millions of years. The report concludes that the window of opportunity to mitigate the effects of climate change is closing fast.
“It is worth recalling that the last time the Earth experienced a comparable concentration of CO2 was 3 to 5 million years ago,” says Petteri Taalas, Secretary-General of WMO. “Back then, the temperature was 2° to 3° C (3.6° to 5.4° F) warmer, sea level was 10 to 20 m (33 to 66 ft) higher than now.”
Sadly, it seems we’re full steam ahead to hit further milestones. The threshold of 400 ppm was first crossed as a global average concentration in 2015, and early data suggests that 2019 could be the year this figure crosses 410 ppm. Already, weather stations have reported individual readings of over 415 ppm.
Carbon dioxide isn’t alone up there, either. The Greenhouse Gas Bulletin also shows that emissions of both methane and nitrous oxide are on the rise, too. In 2018, methane reached a new record of 1,869 parts per billion (ppb) – more than 2.5 times higher than pre-industrial levels. The increase from 2017 to 2018 was higher than that of 2016 to 2017, as well as being above average for the decade.
It’s a similar story for nitrous oxide. This ozone-depleting gas hit new highs of 331.1 ppb in 2018, again with a larger increase than the previous year and the decade average.<<
https://newatlas.com/environment/united-nations-greenhouse-gas-bulletin-2018-record/