Ice Trend

The announcement is based on six leading international data sets consolidated by the World Meteorological Organization (WMO).

Global average temperature for 2021

The HadCRUT5 dataset is compiled by the Met Office and the University of East Anglia, with support from the National Center for Atmospheric Research. HadCRUT5 is the most recent dataset to report its global findings for 2021. It shows that the year was 0.76 ± 0.04 °C above the 1961-1990 average, placing it sixth warmest (along with 2018).

Compared to the pre-industrial global reference period, the year was 1.1 ± 0.1 °C above the 1850-1900 average. This aligns extremely well with figures already published by other international centers.

Authorized evaluation

The WMO uses six international data sets to provide an authoritative assessment of global temperature change. They reported that 2021 was about 1.11 ± 0.13 °C warmer than the 1850-1900 average. based on an average of the six data sets. 2021 is the seventh consecutive year (2015-2021) in which global temperature has been more than 1.0°C above pre-industrial levels, based on all data sets used by the WMO.

The ranking of individual years often depends on small or marginal differences between years and may vary slightly between data sets. However, long-term warming is clear.

Since the 1980s, each decade has been warmer than the last and this is expected to continue..

The seven warmest years have all been since 2015, with 2016, 2019 and 2020 in the top three. An exceptionally strong El Niño event occurred in late 2015 and continued into early 2016.

Dr Colin Morice of the Met Office said: “2021 is one of the warmest years on record and continues a series of measurements of a world that is warming under the effects of greenhouse gas emissions. This extends a streak of remarkably warm years from 2015 to 2021, the seven warmest years in more than 170 years of measurements.”.

Professor Tim Osborn, from the University of East Anglia, said: “Each year tends to be a little below or a little above long-term underlying global warming. Global temperature data analyzed by the Met Office and the UEA Climate Research Unit shows that 2021 was slightly below, while 2020 was slightly above, the underlying warming trend. Every year, including 2021, is consistent with past predictions of warming due to human activities”.

“Back-to-back La Niña events mean that 2021’s warming was relatively less pronounced compared to recent years. Even so, it remained warmer than previous years influenced by La Niña. The overall long-term warming as a result of greenhouse gases is now much greater than the year-to-year variability caused by natural climatic factors.”, said WMO Secretary-General Prof. Petteri Taalas.

Global warming and other long-term climate change trends are expected to continue as a result of record levels of greenhouse gases that trap heat in the atmosphere.

January 19, 2022

Grahame Madge

Met Office