The average temperature of the earth's surface, both in the atmosphere and in the seas and oceans, will continue to increase and, most likely, will set new records in the next five years due to the continuous increase in the concentration of greenhouse gases (such as carbon dioxide). carbon, CO₂) and the appearance of a new cycle of the El Niño-Southern Oscillation phenomenon (whose start could occur this year), according to the update of predictions for the period 2023-2027 published this Wednesday, May 17, by the Meteorological Organization World (WMO).
This new report from the UN agency in charge of meteorology reaffirms the predictions made last May. It warned that the probable appearance of the El Niño phenomenon could cause a global increase in temperatures in the coming months. In this sense, the new communication may seem redundant or superfluous, but in reality it is an ex officio periodic update report (the Global annual to decadal climate update) in which every May the WMO shows predictions for an entire five years (in this case, 2023-2027).
Two of the highlighted sections of the new report try to answer these questions: will we have a new record for the warmest year in history in the next five years (since records have been kept)? And will the symbolic barrier marked in the Paris Agreement (on climate change) of an increase of 1.5ºC with respect to the temperature prior to the industrial era be overcome?
The answers in the WMO report are given in statistical (probability) values.
To the first question, the summary says verbatim: "There is a 98% probability that at least one of the next five years, and the five-year period as a whole, will be the warmest on record."
The second answer is this: “There is a 66% chance that the annual average global temperature between 2023 and 2027 will mark an increase of more than 1.5°C relative to pre-industrial levels for at least one year.”
The WMO explains that the results of this report do not mean "that we will permanently exceed the 1.5°C level" specified in the Paris Agreement, which refers to long-term warming over many years. However, "WMO is sounding the alarm that we will exceed the 1.5°C level temporarily and with increasing frequency," said WMO Secretary General Petteri Taalas.
“A warming El Niño is expected to develop in the coming months, and this will combine with human-induced climate change to push global temperatures into uncharted territory,” Petteri says. “This will have far-reaching implications for health, food safety, water management and the environment. We need to be prepared”, says the Secretary General in an official note from the WMO, an entity that acts as the authorized spokesperson for the United Nations system on weather, climate and water.
The chance of temporarily exceeding the 1.5°C Paris Agreement barrier has risen steadily since 2015, when it was close to zero. The WMO recalls that in the report issued for the period 2017 to 2021, the probability of exceeding this threshold was only 10%.
The average global temperature in 2022 was about 1.15°C above the 1850-1900 average. The cooling influence of La Niña conditions (the opposite phenomenon of El Niño) over much of the last three years temporarily halted the long-term warming trend. But La Niña ended in March 2023, and El Niño is forecast to develop in the coming months. El Niño typically increases global temperatures in the year after it develops; in this case, it would be 2024, says the WMO report.
The global annual mean near-surface temperature for each year between 2023 and 2027 is projected to be between 1.1°C and 1.8°C higher than the 1850-1900 average. As will be remembered, the estimated data for the period 1850-1900 are used as a reference because it was then when the concentrations of greenhouse gases increased due to human and industrial activities.
Arctic warming is disproportionately high. Compared to the 1991-2020 average, the temperature anomaly is forecast to be more than three times larger than the global mean anomaly when averaged over the next five extended Northern Hemisphere winters.
Predicted precipitation patterns for the 2023-2027 May-September average, compared to the 1991-2020 average, suggest increased precipitation in the Sahel, northern Europe, Alaska, and northern Siberia, and a reduction in rainfall for this season in the Amazon and parts of Australia.
