Earth just hit a new milestone, and it’s not good
Greenhouse gases rose to a symbolic milestone in 2015, taking climate change into a new phase which could last generations even if governments act to curb man-made global warming, the UN World Meteorological Organisation (WMO) said on Monday.
Globally averaged concentrations of carbon dioxide, the main man-made greenhouse gas, reached 400.0 parts per million (ppm) in the atmosphere for the first time on record and were 44 per cent above levels before the Industrial Revolution, it said.
The rise, continuing in 2016, contrasts with accords by almost 200 governments to start reining in emissions, led by the Paris Agreement last year to phase out fossil fuels in favour of renewable energy in the second half of the century.
“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,” WMO Secretary-General Petteri Taalas said in a statement.
Carbon dioxide levels had reached 400 ppm in some places and some months but “never before on a global average basis for the entire year,” the WMO said in an annual Greenhouse Gas Bulletin.
And the gas is set to keep building up in the atmosphere unless scientists develop new technologies to extract carbon from the atmosphere. Man-made warming is blamed for causing heatwaves, downpours, droughts and rising ocean levels.
“The real elephant in the room is carbon dioxide, which remains in the atmosphere for thousands of years,” Talaas said.
An observatory at Mauna Loa in Hawaii, the main measuring station with records back to 1958, “predicts that carbon dioxide concentrations will stay above 400 ppm for the whole of 2016 and not dip below that level for many generations”, the WMO said.
Worldwide in 2015, average levels carbon dioxide were at 400.0 ppm, up 2.3 ppm from 2014, it said.
A powerful El Nino weather event, which warms the eastern Pacific Ocean, was also probably driving global rises in 2016. The El Nino is linked with more droughts and wildfires in the tropics, meaning less vegetation to absorb carbon dioxide.
The UN panel of climate scientists estimates that concentrations of carbon dioxide, methane and nitrous oxide are at their highest in at least 800,000 years.
Carbon dioxide levels were 144 per cent of pre-industrial levels of 278 ppm, methane levels were 256 per cent of pre-industrial levels at 1,845 parts per billion and nitrous oxide levels were 121 per cent at 328 parts per billion, it said.