2020 closes warmest decade on record

MANILA, Philippines — As 2020 draws to an end, it closes the warmest decade on record and becomes one of the three hottest years ever measured, the United Nations weather agency reported.

Despite the cooling La Niña event, the World Meteorological Organization (WMO) said 2020 has been a year of exceptional heat that is now mature and impacting weather patterns in many parts of the world.

Citing most models, the WMO said La Niña is expected to peak in intensity in either December or January and continue through the early part of 2021.

“Record warm years have usually coincided with a strong El Niño event, as was the case in 2016,” said WMO chief Petteri Taalas.

However, he noted, “we are now experiencing a La Niña, which has a cooling effect on global temperatures, but has not been sufficient to put a brake on this year’s heat.”

“Despite the current La Niña conditions, this year has already shown near record heat comparable to the previous record of 2016,” Taalas said.

WMO has also documented the last six years as being the warmest.

Next month, the UN agency will issue consolidated temperature figures for 2020, based on five global temperature datasets.

This will be incorporated into a final report on the State of the Climate in 2020, which will be issued in March and will include information on selected climate impacts.

To date, all five datasets for the first 10 months of 2020 have placed this year as the second warmest for the year to date, following 2016 and ahead of 2019.

Based on monthly reports from the European Union’s Copernicus Climate Change Service, the United States National Oceanic and Atmospheric Administration and NASA’s Goddard Institute for Space Studies and the Japan Meteorological Agency, November has been classified as either the warmest or second warmest on record.

The difference between the warmest three years, the WMO said, is small and exact rankings for each data set could change once data for the entire year are available.

The UN weather agency explained that ranking temperatures for individual years is less important than long-term trends.

Since the 1980s each decade has been warmer than the previous one. And because of record levels of heat-trapping greenhouse gases in the atmosphere, the trend is expected to persist.

In particular, carbon dioxide is driving the planet to future warming because it remains in the atmosphere for many decades.

The average global temperature in 2020 is set to be about 1.2 °C above the pre-industrial (1850-1900) level.

According to?WMO’s Global Annual to Decadal Climate Update, led by the United Kingdom’s Met Office, there is a one-in-five chance that the average global temperature will temporarily exceed 1.5 °C by 2024.

The Met Office annual global temperature forecast for 2021 suggests that next year will once again enter the series of the Earth’s hottest years, despite being influenced by the temporary cooling of La Niña, the effects of which are typically strongest in the second year of the event.