After two consecutive years (2019 and 2020) ranked among the three hottest on record, Earth continued to warm in 2021. According to an analysis by the National Oceanic and Atmospheric Observation Agency (NOAA), 2021 ranked sixth on the list of hottest years on record since records began in 1880.
This lower ranking is partly due to La Niña, a weather phenomenon that causes average temperatures to cool. NASA scientists estimate that it may have cooled global temperatures by about 0.06 degrees Fahrenheit (0.03 degrees Celsius) below average.
The past eight years are also the warmest on record. The years 2013-2021 all rank among the ten warmest years on record.
“The science leaves no room for doubt: climate change is the existential threat of our time,” NASA Administrator Bill Nelson said in response to new analyzes released Thursday.
Last year, the Earth was about 1.9 degrees Fahrenheit (or about 1.1 degrees Celsius) warmer than the average for the late 19th century, the start of the Industrial Revolution. The goal of the Paris climate agreement is to keep warming well below 2°C, and preferably 1.5°C, above pre-industrial levels.
The European Earth observation service Copernicus, for its part, ranked 2021 in fifth place in the list of the hottest years. It is not uncommon for agencies to show slight differences in their data due to different methodologies. 2016 remains the hottest year on record.
Heat records
The year 2022 has started with record heat in Australia. The country tied its hottest day on record on Thursday after Onslow, a coastal town, reported temperatures of 50.7C (123.26F). Mercury had not reached this figure since January 1960.
Two other towns, Mardie and Roebourne, reported temperatures of over 50C on the same day. Australia experienced an austral summer marked by major forest fires in the west of the country and deadly floods on its east coast.
Science leaves no room for doubt: climate change is the existential threat of our time.
Recent studies show the direct responsibility of climate change in certain heat waves. The heat wave in Canada in June 2021, with temperatures approaching 50°C, would have been “almost impossible” without the warming, according to scientists from the World Weather Attribution.
The village of Lytton, British Columbia, notably broke the record for the highest temperature in Canada during this heat wave. Environment Canada recorded 49.6°C there on June 29.
Western Canada recently recorded a new record rise in mercury to 22.5°C in December. This temperature was recorded in Penticton, a few hundred kilometers from Lytton.
The December 2021 average temperature over global land and ocean surfaces was 0.83°C above the 20th century average. That value tied with 2016 as Earth’s fifth hottest December in 142 years, according to NOAA.
With Agence France-Presse