Levels of atmospheric greenhouse gases have reached another record high, “with no sign of a slowdown, let alone a decline”, the World Meteorological Organisation (WMO) has warned.

Despite pledges made under the Paris Agreement to combat climate change, concentrations of carbon dioxide, methane and nitrous oxide all surged by higher amounts in 2018 than average for the past decade.

Levels of CO2 – the main gas driving global warming – reached new highs of 407.8 parts per million (ppm) in 2018, up from 405.5ppm the previous year, a report by the UN body shows.

This concentration is now 47 per cent higher than before the Industrial Revolution began in 1760, when CO2 levels were around 280ppm.

“We need to translate the commitments into action and increase the level of ambition for the sake of the future welfare of mankind,” said WMO secretary general Petteri Taalas.

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The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: In this aerial view ice floats jammed into the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: An iceberg looms behind a boat carrying tourists at the mouth of the Ilulissat Icefjord on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Visitors look out onto free-floating ice jammed into the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. 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(Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: A boat carrying tourists motors past an iceberg at the mouth of the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Free-floating ice floats jammed into the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: Humpback whales spout water as they swim next to an iceberg in the Ilulissat Icefjord on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: Icebergs and ice float in the Ilulissat Icefjord on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 31: Tourists on an excursion boat photograph an iceberg during unseasonably warm weather on July 31, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Inuit fishermen prepare a net as free-floating ice floats behind at the mouth of the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Water drips from ice in the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: An iceberg floats in Disko Bay behind houses during unseasonably warm weather on July 30, 2019 in Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. 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(Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: In this view from an airplane rivers of meltwater carve into the Greenland ice sheet near Sermeq Avangnardleq glacier on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Visitors walk among free-floating ice jammed into the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. 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(Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: In this view from an airplane icebergs float in Disko Bay at sunset on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - JULY 30: Flowers stand on a hillside at the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe is arriving in Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 03: A massive iceberg floating in the Ilulissat Icefjord peeks through a bank of fog during a week of unseasonably warm weather on August 3, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) ***BESTPIX*** Sean Gallup Getty Images Climate change: Greenland ice cap accelerated retreating ILULISSAT, GREENLAND - AUGUST 04: In this view from an airplane humpback whales swim next to an iceberg at the mouth of the Ilulissat Icefjord on August 04, 2019 near Ilulissat, Greenland. The Sahara heat wave that recently sent temperatures to record levels in parts of Europe has also reached Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated. (Photo by Sean Gallup/Getty Images) Sean Gallup Getty Images

The last time Earth experienced comparable concentrations of carbon dioxide in the atmosphere was three to five million years ago, when temperatures were 2C to 3C warmer and sea levels were 10-20 metres higher than today, Mr Taalas said.

Human activity is increasing greenhouse gas emissions, which are driving up these gases’ concentration in the atmosphere, where they have a warming effect on the Earth’s climate.

Since 1990, there has been a 43 per cent increase in this warming effect by long-lived greenhouse gases, the report said.

According to the report, CO2 contributes towards 66 per cent of this warming effect, with methane at 17 per cent, and nitrous oxide at six per cent.

The report focuses on concentration levels – which represent what remains in the atmosphere after a complex system of interactions between the atmosphere, land, trees and oceans.

Trees and oceans each absorb roughly a quarter of the total emissions, but this effect is already slowing down in the latter as they grow increasingly warmer.

In addition, global greenhouse gas emissions rose again in 2018 at the fastest rate in seven years, according to a preliminary report by the Global Carbon Project.

The resultant heating of the planet is driving impacts such as melting glaciers and sea level rise, more extreme droughts, heatwaves and storms, also posing a threat to food security, water supplies and wildlife.

If our current emissions trends continue unchecked, many researchers predict mass displacement on an unprecedented scale.

Large swathes of North Africa and the Middle East would likely become uninhabitable due to scorching heat and drought, with sea level rises affecting many of the world’s most populous cities.

The WMO warned that despite agreements made under the Paris Agreement, global emissions are not estimated to peak by 2030, let alone by the 2020 date that scientists have said is necessary to curb dangerous climate change.

“The findings ... point us in a clear direction – in this critical period, the world must deliver concrete, stepped-up action on emissions,” said the UN Environment Programme’s executive director Inger Andersen.

“We face a stark choice: set in motion the radical transformations we need now, or face the consequences of a planet radically altered by climate change.”