Greenhouse gas concentrations in the atmosphere reached record levels last year, the United Nations warned ahead of the COP26 summit about worsening global warming.
The UN's World Meteorological Organization said on Monday that continued rising greenhouse gas emissions would result in more extreme weather and wide-ranging impacts on the environment, the economy and humanity.
"The Greenhouse Gas Bulletin contains a stark, scientific message for climate change negotiators at COP26," said WMO chief Petteri Taalas.
The economic slowdown caused by the Covid-19 pandemic triggered a temporary decline in new emissions, but had no discernible impact on the atmospheric levels of greenhouse gases and their growth rates.
The WMO’s Greenhouse Gas Bulletin said the annual rate of increase last year was above the yearly average between 2011 and 2020 — and the trend continued in 2021.
As long as emissions continue, global temperatures will continue to rise.
'We will see a temperature increase'
Given the long life of carbon dioxide (CO2), the temperature level already observed will persist for several decades even if emissions are rapidly reduced to net zero.
"At the current rate of increase in greenhouse gas concentrations, we will see a temperature increase by the end of this century far in excess of the Paris Agreement targets of 1.5 to two degrees Celsius above pre-industrial levels,” said Taalas.
According to Taalas, if the world kept using fossil fuels in an unlimited way, the planet could be about 4C warmer by 2100 — but limiting warming to 1.5 C was still possible through mitigation efforts.
The WMO said that with continued rising greenhouse gas emissions, alongside rising temperatures, the planet could also expect more extreme weather.
That includes intense heat and rainfall, ice melt, sea-level rise and ocean acidification — all of which will have far-reaching impacts on people across the world.
The UN Climate Change Conference COP26 is being held in the Scottish city Glasgow from October 31 to November 12.