Atmospheric carbon dioxide concentrations surged to a record-breaking level in 2016, according to the World Meteorological Organisation’s Greenhouse Gas Bulletin, their highest in 800,000 years
Atmospheric carbon dioxide concentrations surged to a record-breaking level in 2016, according to the World Meteorological Organisation’s Greenhouse Gas Bulletin, their highest in 800,000 years.
The levels suggest that global efforts to reach the Sustainable Development Goals, upheld by countries around the world including all within the Commonwealth, are failing.
Global average concentrations of CO2 reached 403.3. parts per million (ppm) in 2016, an abrupt increase from 400ppm in 2015.
WMO’s Greenhouse Gas Bulletin is based on observations from the WMO Global Atmosphere Watch Programme, which coordinates systematic observations and analysis of greenhouse gases from data contributed by 51 countries.
This helps to track changes in greenhouse gas levels and acts as an early warning system on key atmospheric drivers of climate change.
Around a quarter of total global emissions are taken up by the oceans and another quarter by the biosphere, reducing the concentration of CO2 left in the atmosphere, which WMO records and analyses.
UN Environment released a separate Emissions Gap Report on October 31, 2017 that tracks and analyses how policy commitments made by countries to reduce emissions will affect reductions through to 2030.
WMO, UN Environment and other partners are working on an Integrated Global Greenhouse Gas Information System, which will provide information to nations to help them track the progress of their national emission pledges, improve emission reporting and inform further mitigation actions.
WMO is also working to improve weather and climate services for the renewable energy sector, supporting the Green Economy and sustainable development.
Key findings of the WMO Greenhouse Gas Bulletin include that CO2 concentrations are now 145% of pre-industrial levels.
CO2 is the most important anthropogenic long-lived greenhouse gas and its rate of increase in atmospheric concentrations over the last 70 years is almost 100 times larger than at the end of the last ice age.
Methane is the second most important and contributes about 17% of radiative forcing, also known as global warming.
Atmospheric concentrations reached 1,853ppb in 2016, 257% pre-industrial level, with approximately 40% emitted by natural sources like wetlands and termites and 60% emitted from human activities like cattle breeding, fossil fuel exploitation, biomass burning and landfills.
Nitrous oxide emission concentrations reached 328.9ppb in 2016, 122% of pre-industrial levels, with 40% contributed to by biomass burning, fertilizer use, industrial processes etcetera and 60% by oceans, soil etcetera.
Nitrous oxide also contributes to the destruction of the stratospheric ozone layer which offers protection from the sun’s harmful ultraviolet rays.
Such unprecedented changes in the atmosphere are down to a combination of human activities and a strong El Niño event.
El Niño refers to a set of complex weather patterns resulting from variations in ocean temperatures, which can trigger droughts in tropical regions and reduce the ability of sinks like oceans, forests and vegetation to absorb CO2.
Population growth, intensified land use, agricultural practices, deforestation, industrialization and the use of fossil fuels for energy have all contributed to the increase in greenhouse gas concentrations in the atmosphere since the industrial era, which began in 1750.
Since 1990, there has been a 40% increase in the warming effect on our climate and a 2.5% increase from 2015 to 2016 alone, according to figures from the US National Oceanic and Atmospheric Administration included in the report.
Rapid increases in atmospheric levels of greenhouse gases could initiate unprecedented changes in the global climate, causing extreme economic and ecological disruption, said the report.
WMO Secretary-General Petteri Taalas has said that unless CO2, which remains in the atmosphere and oceans for hundreds of years, and other greenhouse gas emissions are rapidly and severely cut by the end of the century, dangerous increases in temperature and a more inhospitable planet will follow for future generations.
Earth did experience a comparable concentration of CO2 3-5 million years ago: sea levels were 10-20 metres higher than their current level and temperatures averaged 2-3°C warmer.
Erik Solheim, Head of UN Environment, said: “The numbers don't lie. We are still emitting far too much and this needs to be reversed.
“The last few years have seen enormous uptake of renewable energy, but we must now redouble our efforts to ensure these new low-carbon technologies are able to thrive.
“We have many of the solutions already to address this challenge.
“What we need now is global political will and a new sense of urgency.”