The World Meteorological Organization warns that greenhouse gas concentrations hit a record high last year, increasing at a faster rate than the annual average for the past decade.
In a report released by the agency Monday, the WMO said the results come despite a temporary reduction in emissions during COVID-19-induced lockdowns.
It explained that concentrations of carbon dioxide in the atmosphere reached a new high of 413.2 parts per million in 2020.
This, the report said, was 149 percent higher than levels recorded before industrialization.
It added that methane and nitrous oxide levels were also at record highs, at 262 and 123 percent, respectively, of levels seen in 1750, before the industrial revolution.
The Geneva-based agency says the world needs to act now.
"And we have to start dealing with the emissions already during this decade. We cannot wait. Otherwise we will lose the Paris targets and we would suffer for the coming hundreds or even thousands of years because of high level of carbon dioxide, which is the most important part of that."
The organization also pointed to a new cause for concern.
It said parts of the Amazon rainforest have gone from being so-called "carbon sinks" that suck the gas from the air to a source of CO2, mainly because of deforestation and reduced human populations in the region.
Kim Hyo-sun, Arirang News.