The concentration of greenhouse gases in the atmosphere has reached a record high last year prompting the World Meteorological Organisation (WMO) to call for an immediate intervention to keep warming manageable.
Levels of carbon dioxide, the most significant greenhouse gas, averaged 397.7 parts per million (ppm) in 2014, a 43 per cent increase on pre-industrial levels of around 278 ppm, according to WMO.
In the northern hemisphere, concentrations of carbon dioxide broke through the symbolic 400 ppm threshold in Spring of 2014, when the gas is most abundant, and again this spring when concentration reached the 400 ppm level worldwide.
"Every year we report a new record in greenhouse gas concentrations. Every year we say that time is running out,” said WMO secretary-general Michel Jarraud.
"We have to act now to slash greenhouse gas emissions if we are to have a chance to keep the increase in temperatures to manageable levels."
The warming impact on the climate of long-lived gases such as carbon dioxide, methane and nitrous oxide, released from burning fossil fuels and other activities such as farming as well as natural processes, increased by more than a third (36 per cent) between 1990 and 2014.
Higher levels of carbon dioxide (CO2) are also increasing the amount of water vapour in the atmosphere, as warmer air holds more moisture, which in turn causes further warming as water vapour is a short-lived but major greenhouse gas, the WMO said.
"It means hotter global temperatures, more extreme weather events like heatwaves and floods, melting ice, rising sea levels and increased acidity of the oceans,” Jarraud said.
“This is happening now and we are moving into uncharted territory at a frightening speed."
Today, the UK Met Office also announced that 2015 has been the first year in history when average global temperatures have reached 1°C above pre-industrial levels.
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