Greenhouse gases were at an all-time high in the atmosphere in 2013, according to a new report by the World Meteorological Organization.
Carbon dioxide (CO2) and methane are the two most common greenhouse gases emitted by human activities, with CO2 at 396.0 parts per million (ppm) in 2013, 2.9 ppm higher than in 2012, while methane reached 1,824 parts per billion (ppb). CO2 experienced the highest increase in one year since reliable records began in 1984.
The BBC reports:
Atmospheric CO2 is now at 142% of the levels in 1750, before the start of the industrial revolution.
However, global average temperatures have not risen in concert with the sustained growth in CO2, leading to many voices claiming that global warming has paused.
"The climate system is not linear, it is not straightforward. It is not necessarily reflected in the temperature in the atmosphere, but if you look at the temperature profile in the ocean, the heat is going in the oceans," said Oksana Tarasova, chief of the atmospheric research division at the WMO.
The bulletin suggests that in 2013, the increase in CO2 was due not only to increased emissions but also to a reduced carbon uptake by the Earth's biosphere.
The scientists at the WMO are puzzled by this development. That last time there was a reduction in the biosphere's ability to absorb carbon was 1998, when there was extensive burning of biomass worldwide, coupled with El Nino conditions.
"In 2013 there are no obvious impacts on the biosphere so it is more worrying," said Oksana Tarasova.
World leaders will meet at the United Nations Climate Summit in New York City on Sept. 23. This new information clearly should be on the agenda.
"We know without any doubt that our climate is changing and our weather is becoming more extreme due to human activities such as the burning of fossil fuels. Time is not on our side, for sure," said the organization's Secretary-General Michel Jarraud in a statement. "Past, present and future CO2 emissions will have a cumulative impact on both global warming and ocean acidification. The laws of physics are non-negotiable. We're running out of time."
"Pleading ignorance can no longer be an excuse for not acting," Jarraud said.