Concentrations of carbon dioxide (CO2) in the Earth’s atmosphere surged to a record high in 2016, according to the World Meteorological Organization (WMO).
Last year’s increase was 50% higher than the average of the past 10 years. Researchers say a combination of human activities and the El Niño weather phenomenon drove CO2 to a level not seen in 800,000 years. Scientists say this risks making global temperature targets largely unattainable.
This year’s greenhouse gas bulletin produced by the WMO is based on measurements taken in 51 countries. Research stations dotted around the globe measure concentrations of warming gases including carbon dioxide, methane and nitrous oxide. The figures published by the WMO are what’s left in the atmosphere after significant amounts are absorbed by the Earth’s “sinks”, which include the oceans and the biosphere.
Over the past 70 years, the increase in CO2 in the atmosphere is nearly 100 times larger than it was at the end of the last ice age. Rapidly increasing atmospheric levels of CO2 and other gases have the potential, according to the study, to “initiate unpredictable changes in the climate system… leading to severe ecological and economic disruptions”. Another concern is the continuing, mysterious rise of methane levels in the atmosphere, which were also larger than the average over the past 10 years.
According to experts, the last time the Earth experienced a comparable concentration of CO2 was three to five million years ago, in the mid-Pliocene Epoch. The climate then was 2-3C warmer, and sea levels were 10-20m higher due to the melting of Greenland and the West Antarctic ice sheets.
(Source: BBC News)