New study predicts consistent annual increases in global temperature

New World Meteorological Organization climate predictions assess global temperatures for the next five years

View of Earth from the International Space Station. (Pixabay)

The annual mean global temperature is likely to be at least 1.8° Fahrenheit above pre-industrial levels (1850-1900) in each of the coming five years (2020-2024) and there is a 20% chance that it will exceed 2.7°F in at least one year, according to new climate predictions issued by the World Meteorological Organization (WMO) -- a specialized agency within the United Nations.

The Global Annual to Decadal Climate Update, led by the United Kingdom’s Meteorological Office, provides a climate outlook for the next five years and is updated annually. The update harnesses the expertise of internationally acclaimed climate scientists and the best computer models from leading climate centers around the world to produce actionable information for decision makers.

The earth’s average temperature is already over 1.8° F above the pre-industrial period. The last five-year period has been the warmest five years on record.

“This study shows -- with a high level of scientific skill -- the enormous challenge ahead in meeting the Paris Agreement on Climate Change target of keeping a global temperature rise this century well below 2 degrees Celsius (3.6° F) above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius (2.7° F),” said WMO Secretary-General Petteri Taalas.

The predictions take into account natural variations as well as human influences on climate to provide the best possible forecasts of temperature, rainfall, wind patterns and other variables for the coming five years. The forecast models do not take into consideration changes in emissions of greenhouse gases and aerosols as a result of the coronavirus (COVID-19) lockdown.

“WMO has repeatedly stressed that the industrial and economic slowdown from COVID-19 is not a substitute for sustained and coordinated climate action,” Taalas said. “Due to the very long lifetime of CO2 in the atmosphere, the impact of the drop in emissions this year is not expected to lead to a reduction of CO2 atmospheric concentrations which are driving global temperature increases.”

Professor Adam Scaife, head of long-range prediction at the UK Meteorology Office Hadley Centre, says the annual report will be especially helpful even outside of the scientific community.

“This is an exciting new scientific capability,” Scaife said. “As human-induced climate change grows, it is becoming even more important for governments and decision makers to understand the current climate risks on an annually-updated basis.”

Predictions illustrated by the World Meteorological Organization. Ensemble mean forecast for 2020-202 expressed as anomalies with respect to the 1981-2010 climatology: top: temperature (left column) and probability of above average (right column), sea-level pressure (middle) and precipitation (bottom). As this is a two-category forecast, the probability for below average is one minus the value in the right column. (WMO)

WMO listed the following key takeaways from their report:

  • Annual global temperature is likely to be at least 1.8°F warmer than preindustrial levels (defined as the 1850-1900 average) in each of the coming five years.
  • There is a ~70% chance that one or more months during the next five years will be at least 2.7°F warmer than preindustrial levels.
  • There is a ~20% chance that one of the next five years will be at least 2.7°F warmer than preindustrial levels, but the chance is increasing with time.
  • It is extremely unlikely (~3%) that the entire five-year mean temperature for 2020-2024 will be 2.7°F warmer than preindustrial levels.
  • Over 2020-2024, almost all regions, except parts of the southern oceans, are likely to be warmer than the recent past.
  • In 2020, large land areas in the Northern Hemisphere are likely to be over 1.4°F warmer than the recent past (defined as the 1981-2010 average).
  • In 2020, the Arctic is likely to have warmed by more than twice as much as the global mean.
  • The smallest temperature change is expected in the tropics and in the mid-latitudes of the Southern Hemisphere.
  • In 2020, many parts of South America, southern Africa and Australia are likely to be dryer than the recent past.

The development of near-term prediction capability was driven by the WMO co-sponsored World Climate Research Programme. With the UK’s Meteorology Office acting as lead center, climate prediction groups from Spain, Germany, Canada, China, the U.S., Japan, Australia, Sweden and Denmark contributed new predictions this year. Combining forecasts from climate prediction centers worldwide enables a higher quality product than what can be obtained from any single source.

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