The global increase in carbon dioxide concentrations in the atmosphere to 400 ppm has ushered in a new climate area, concluded scientists from the UN’s weather agency. As Elke Bunge reports, carbon dioxide remains in the atmosphere for thousands of years, trapping heat and causing the Earth to warm further.
The all clear from Geneva remains elusive. In the latest Greenhouse Gas Bulletin, scientists from the World Meteorological Organization (WMO) confirmed the dire measurements recorded in September by American researchers at the Mauna Loa Observatory on Hawaii and the Global Greenhouse Gas Reference Network: 2016 is the first year in which carbon dioxide concentrations in the atmosphere constantly reached and even exceeded 400 ppm (parts per million).
The experts from the UN weather agency don’t expect the value to dip below pre-2015 levels for generations to come. The last time in the Earth’s history that carbon dioxide concentrations in the atmosphere were consistently above the 400 ppm value was five million years ago.
Human-induced CO2 concentrations
Between 1990 and 2015, WMO meteorologists found a 37 per cent increase in radioactive forcing – or the warming effect on our climate – due to human-induced greenhouse gas emissions from industrial, agricultural and domestic activities. Unless dramatic measures are taken, this trend will continue to rise unabated.
Climate researchers worldwide are already warning that we may soon reach the tipping point when it will no longer be conceivable or feasible to reverse the trajectory of climate change. According to the WMO, the Earth is already one degree Celsius hotter than at the start of the 20th century, putting our planet halfway to the critical two-degree threshold.
Due to the increase in CO2 concentrations, the meteorologists expect a rise in extreme weather conditions: in drought-prone regions, plants and trees will continue to die, preventing them from absorbing even less carbon dioxide (let alone producing less oxygen). Cloud banks will shift further towards the poles. There could be an increase in the intensity of torrential rainfall and floods. The resulting temperature and air pressure fluctuations could lead to devastating storms.
Politics under fire
“The year 2015 ushered in a new era of optimism and climate action with the Paris climate change agreement. But it will also make history as marking a new era of climate change reality with record high greenhouse gas concentrations,” said WMO Secretary-General Petteri Taalas on the release of the report. “The El Niño event has disappeared. Climate change has not.”
Taalas is calling for more consistent action by political leaders. While the recent agreement in Kigali to amend the Montreal Protocol and phase out hydrofluorocarbons is good news, “the real elephant in the room is carbon dioxide,” he said. Declarations of intent and promises will do little to halt climate change in its tracks.
Climate conference in Marrakesh
The WMO sees its latest Greenhouse Gas Bulletin as a scientific base for decision-making at the upcoming UN climate change negotiations in Marrakesh, Morocco, which will begin on 7 November.
If the international community is genuinely committed to limiting temperature rise to less than two degrees Celsius by the end of this century as agreed upon in Paris, it must act now.
Carbon dioxide concentrations in the atmosphere in 1800 were 278 ppm. Human activities such as burning fossil fuels have increased globally averaged CO2 levels to 144 per cent of their pre-industrial levels. The increase of CO2 from 2014 to 2015 was larger than the previous year and the average over the previous 10 years.
WMO experts warn that it will be difficult to return to the starting value.