The Copernicus Climate Change Service (C3S), an EU scientific information agency, said in its annual report Monday that average temperatures in 2021 were among the highest ever recorded in Europe , adding that the year was the latest in a string of seven of the hottest on record and the fifth-warmest overall globally.

Scientists at C3S said temperatures from 2015 until today have been the hottest globally "by a clear margin."  

"2021 was yet another year of extreme temperatures, with the hottest summer in Europe, heat waves in the Mediterranean, not to mention the unprecedented high temperatures in North America," C3S director Carlo Buontempo said.

"These events are a stark reminder of the need to change our ways, take decisive and effective steps toward a sustainable society, and work towards reducing net carbon emissions," he added. 

According to C3S, in 2021 the annual average temperature was 1.1-1.2 degree Celsius (2-2.16 F) above preindustrial levels measured from 1850 and 1900 — when scientists first began accurately recording temperatures.

Greenhouse gas increases drive warming

C3S also tracks carbon dioxide (CO2) and methane (CH4) levels in the Earth's atmosphere and warned of deadly emissions increases in its report, noting that methane levels had increased "very substantially."

Scientists say there are no indications that the trend will stop.

They recorded carbon dioxide increases of 2.4 parts per billion (ppb) in 2021, and methane emissions increases of 14.6 ppb in 2020 and 16.3 ppb in 2021. The scientists say the methane emissions increased at twice the average rate recorded over the previous 17 years.

After CO2, methane is one of the biggest drivers of atmospheric warming, and scientists at C3S say reducing methane emissions is crucial to avoid "climate catastrophe."

Nearly 100 countries — China not among them — pledged to reduce methane emissions by at least 30% within the decade when they met for the COP26 climate summit in November.

Scientists at C3S say it is unclear where the increase in emissions comes from exactly, as methane is emitted in fossil fuel production, as well as occurring naturally, in wetlands, for instance.

Methane emissions reductions represent the most direct path to reducing the "emissions gap" between the temperature cap set in the 2015 Paris climate agreement of 1.5 C above preindustrial levels and the predicted 2.7-degree increase the world faces.

What do emissions and temperature have to do with the climate?

Scientists see a direct link between the atmospheric changes recorded by C3S and extreme weather around the world. In 2021, these included wildfires in Australia and Siberia, a once in a millennium heatwave in the US and Canada, and flooding in Africa, Asia, Europe and the US.

Such extreme weather situations have decimated crops in countries such as France and Hungary; stoked heat waves that sparked intense wildfires in Turkey, Greece and elsewhere; and caused flooding that killed more than 200 people in Germany, Belgium and the Netherlands.

Flooding also killed more than 300 people in China's Henan province last summer, at the same time the US state of California experienced a record-crushing heatwave directly followed by the second-largest wildfire in state history.

js/wmr (AFP, dpa, Reuters)