The likelihood of crossing a key global warming threshold has risen significantly, according to a new analysis. According to UK Met Office researchers, there is now a fifty-fifty chance that the world will warm by more than 1.5 degrees Celsius over the next five years.
Although such a rise would be transient, researchers are concerned about the overall trend of temperatures. They predict that the years 2022-2026 will be the warmest on record. Global temperatures have risen in lockstep with rising levels of warming gases in the atmosphere over the last three decades.
In 2015, the global average temperature surpassed 1 degree Celsius above pre-industrial levels, which are generally regarded as temperatures recorded in the middle of the nineteenth century.
That was also the year that political leaders signed the Paris Climate Agreement, which committed the world to keep global temperature rises well below 2 degrees Celsius while pursuing efforts to keep them under 1.5 degrees Celsius.
Governments reaffirmed their commitment to keeping "1.5C alive" at COP26 in Glasgow last November. Global temperatures have remained at or near 1 degree Celsius for the past seven years, with 2016 and 2020 essentially tied as the warmest years on record.
According to scientists, with only 1 degree Celsius of warming, the world is already experiencing significant impacts, such as the unprecedented wildfires seen in North America last year or the severe heatwaves currently affecting India and Pakistan.
According to this World Meteorological Organization (WMO) update, carried out by the UK Met Office, the chances of temporarily exceeding 1.5 degrees Celsius in one of the next five years have never been higher.
According to the study, temperatures between 2022 and 2026 will be 1.1 to 1.7 degrees Celsius higher than pre-industrial levels. The Met Office researchers predict that the likelihood of exceeding 1.5 degrees Celsius in any given year is around 48 percent, or close to 50:50.
"The basic thing that's changing is that carbon dioxide levels in the atmosphere are slowly creeping up," said lead author Dr Leon Hermanson of the Met Office.
"I think people are already concerned about climate change, and it is concerning because it shows that we are continuing to warm the planet and are getting closer to the first threshold set in the Paris agreement - and we need to continue doing everything we can to reduce our reliance on fossil fuels."
According to the researchers, going above 1.5 degrees Celsius for one year is not the same as a sustained rise in which temperatures do not fall below this level. If it is exceeded in the next five years, it will most likely fall below 1.5 degrees Celsius again. However, there is no longer any room for complacency.
"Temperatures will continue to rise as long as we continue to emit greenhouse gases," said WMO Prof Petteri Taalas. "Along with that, our oceans will continue to warm and acidify, sea ice and glaciers will melt, sea level will rise, and our weather will become more extreme," he said.
According to the study, the Arctic region will likely be hit harder by warming than the rest of the world over the next five years. According to the researchers, the temperature difference from the long-term average will be three times as large in these areas.
The researchers also believe that one of the coming years will likely break the record for the warmest years set in 2016 and 2020. That will occur, most likely during an El Nio year. This is a natural, meteorological phenomenon caused by an unusual warming of the surface waters of the eastern Pacific Ocean, which has the potential to affect weather all over the world.
"The year we do temporarily exceed 1.5 degrees will almost certainly be an El Nio year," said Dr Hermanson of the Met Office. "It's on top of climate change, like the wiggles on top of the trend, if you will, and the next record year will almost certainly be an El Nio year, as 2016 was."
