
The recent streak of record-breaking hot years is set to continue throughout the next decade. It is likely that every year from 2019 to 2028 will be one of the 10 warmest on record.
“After the last five years, we’ve really separated ourselves from the past,” says Anthony Arguez at NOAA’s National Centers for Environmental Information in Asheville, North Carolina. “It looks pretty likely that we’re going to have a whole lot of top 10 years.”
Many recent years have been among the warmest we have seen, as the global climate heats up due to our greenhouse gas emissions. For instance, 2019 was the second warmest, according to NOAA and NASA. The hottest year on record was 2016.
Advertisement
This is in stark contrast to the early 2000s, when the warming slowed – although reports it had halted were false. Such slowdowns happen because of natural variations in global temperature, caused by weather phenomena like El Niño, which overlay the steady warming trend.
To find out what is likely to happen over the next 10 years, Arguez and his colleagues examined the temperature record from 1975 to 2018. They looked at how much the temperature fluctuated from year to year, with and without the warming trend, and used that to estimate how big the fluctuations will be from now until 2028.
Their calculations suggest there is a 75 per cent chance that every year from 2019 to 2028 will be in the all-time top 10, and a 99 per cent chance that the majority will be. Even if we have a run of relatively cool years, these natural fluctuations are unlikely to be enough to offset the warming trend.
“We should really expect to have top 10 years for most of the next decade,” says Arguez, “unless there’s something truly remarkable.” A volcanic eruption that pumps aerosols into the stratosphere would have a cooling effect, but Arguez says it would need to be a very big one to prevent record-breaking warm years.
Bulletin of the American Meteorological Society