The concentration of carbon dioxide in the atmosphere increased last year at the fastest rate for nearly 30 years, according to the World Meteorological Organization (WMO).
In its annual greenhouse-gas bulletin, the WMO says CO2 levels increased more between 2012 and 2013 than during any other year since 1984.
Preliminary data indicated that this was possibly related to reduced uptake of carbon by the earth’s biosphere in addition to steadily rising CO2 emissions.
The bulletin tracks levels of atmospheric concentrations of greenhouse gases, rather than emissions. Emissions represent what goes into the atmosphere, while concentrations represent what remains in the atmosphere after interactions between the atmosphere, biosphere and the oceans.
The WMO found that the concentration of CO2 in the atmosphere in 2013 was 142% that of the pre-industrial era (1750), while the concentration of methane and nitrous oxide was 253% and 121% respectively.
About a quarter of total GHG emissions are taken up by the biosphere, and another quarter is absorbed by the oceans. The study found that the current rate of ocean acidification appears to be unprecedented at least over the past 300 million years.
“Carbon dioxide remains in the atmosphere for many hundreds of years and in the ocean for even longer,” said WMO secretary-general Michel Jarraud.
“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.”
Wendy Watson-Wright, executive secretary at the Intergovernmental Oceanographic Commission of UNESCO, commented: “It is high time the ocean, as the primary driver of the planet’s climate and attenuator of climate change, becomes a central part of climate change discussions.
If global warming is not a strong enough reason to cut CO2 emissions, ocean acidification should be, since its effects are already being felt and will increase for many decades to come.”
Energy and climate secretary Ed Davey is today launching the government’s strategy for next year’s international climate summit in Paris.
In a statement to parliament, he said: “Paris will not be the end of the road in terms of tackling climate change, but an ambitious agreement would be a huge step forward which we can then build on in the future.”
