UN: Gas emissions reach new high
Levels of the three main heat-trapping gases emitted into the atmosphere — carbon dioxide (CO2), methane, and nitrous oxide — have reached yet another high, the UN meteorological agency World Meteorological Organization (WMO) said.
In an appeal to governments to do more to reverse countries’ reliance on producing energy from fossil fuels in line with the 2015 Paris Agreement on Climate Change, WMO Secretary-General Petteri Taalas, warned that “the future welfare of mankind” was at stake.
“We have again broken records in carbon dioxide concentrations and we have already exceeded 400ppm level which was regarded as a critical level,” he said, in reference to the 407.8 parts per million reading for 2018.
“That happened already two years ago and this carbon dioxide concentration continues and continues, and last year’s increase was about the same as we have been observing in the past 10 years, as an average.” According to the World Meteorological Organization’s Greenhouse Gas Bulletin, since 1990, so-called “long-lived” greenhouse gases have caused a 43 percent increase in total radiative forcing — the warming effect on the climate.
Of these gases, CO2 accounts for about 80 percent, according to the United States’ National Oceanic and Atmospheric Administration (NOAA), whose data is quoted in the WMO Bulletin.
CO2 is particularly harmful in a global warming context because it remains in the atmosphere for centuries and in the oceans for even longer, the agency explained.
Professor Taalas noted too that when the Earth last had similar concentrations of CO2, the temperature “was 2-3 degrees Celsius warmer (and) sea level was 10-20 meters higher than now.”
Turning to methane, which is responsible for 17 percent of radiative forcing, Professor Taalas noted that “we have also been breaking records”, since last year’s increase “was the second-highest in the last 10 years.”
According to the WMO bulletin, global readings indicate that atmospheric methane (CH4) reached a new high of 1,869 parts per billion in 2018, more than two and a half times the pre-industrial level.