by Ian Angus
There is a 40% chance that the annual average global temperature in at least one of the next five years will temporarily reach 1.5°C above pre-industrial levels, and a 90% likelihood that at least one year in the five-year period will be the warmest on record, passing the previous record set in 2016.
This does not mean that the world will have definitively passed the Paris Agreement’s 1.5°C limit, but as the Secretary General of the World Meteorological Organization says, “we are getting measurably and inexorably closer.”
The latest Global Annual to Decadal Climate Update, prepared by the UK Met Office and issued on May 27 by the World Meteorological Organization, includes these projections for 2021-2025:
- Annual mean global (land and sea) mean near-surface temperature is likely to be at least 1°C warmer than pre-industrial levels (defined as the average over the years 1850-1900) in each of the coming 5 years and is very likely to be within the range 0.9 – 1.8°C.
- It is about as likely as not (40% chance) that at least one of the next 5 years will be 1.5°C warmer than pre-industrial levels and the chance is increasing with time.
- It is very unlikely (10% chance) that the five-year mean global near-surface temperature for 2021-2025 will be 1.5°C warmer than pre-industrial levels.
- The chance of at least one year exceeding the current warmest year, 2016, in the next five years is 90%.
- Over 2021-2025, almost all regions, except parts of the southern oceans and the North Atlantic are likely to be warmer than the recent past (defined as the 1981-2010 average).
- Over 2021-2025, high latitude regions and the Sahel are likely to be wetter than the recent past.
- Over 2021-2025 there is an increased chance of more tropical cyclones in the Atlantic compared to the recent past.
- In 2021, large land areas in the Northern Hemisphere are likely to be over 0.8°C warmer than the recent past.
- In 2021, the Arctic (north of 60°N) is likely to have warmed by more than twice as much as the global mean compared to the recent past.
- In 2021, southwestern North America is likely to be drier whereas the Sahel region and Australia are likely to be wetter than the recent past.
In 2020 – one of the three warmest years on record – the global average temperature was 1.2 °C above the pre-industrial baseline, according to the WMO’s State of the Global Climate 2020, released last month. It highlighted the acceleration in climate change indicators like rising sea levels, melting sea ice, and extreme weather, as well as worsening impacts on socio-economic development.
The Global Annual to Decadal Climate Update confirms that trend. In the coming five years, the annual mean global temperature is likely to be between 0.9°C and 1.8°C above pre-industrial levels.