Climate Matters•January 14, 2021
2020 in Review: Global Temperature Rankings
KEY CONCEPTS
The global temperature analyses are in, with NASA ranking 2020 as the warmest year on record (tied with 2016), and NOAA ranking it as the second warmest (see methodology below). Combining their data, 2020 was 2.25°F (1.25°C) over the 1881-1910 baseline normal.
The top 10 warmest years on record have all occurred since 2000—this outsized frequency of record high global temperatures is another symptom of climate change.
Despite La Niña conditions emerging in the second half of the year, 2020 was still able to secure a spot as one of the two warmest years on record because we continue to emit greenhouse gases that warm our planet.
With annual global temperature numbers in, Ed Hawkins added a 2020 stripe to his famous warming stripes.
Climate Central combined data from both NOAA and NASA to reveal the global temperature rankings compared to an early industrial baseline. Averaging the datasets shows that 2020 was 2.25°F (or 1.25°C) over the 1881-1910 baseline average.
Long term global temperature trends indicate that the Earth is warming and at an unprecedented rate. The six warmest years have occurred since 2015 and the top 10 warmest years have all happened since 2000. In general, a stable climate is characterized by a balance of warm and cold years. However, the frequency at which we are setting new annual warm records, combined with the longer warming trend of global temperatures over the past decades, adds to the multiple lines of evidence of human-induced climate change.
Furthermore, 2020’s ranking is significant because it occurred during a developing La Niña. La Niña and its opposite, El Niño, correspond to variations in water temperatures in the Pacific Ocean. These usually result in a boost (El Niño) or a dip (La Niña) in extra heat added to the atmosphere. According to NOAA, when comparing 2020 with similar La Niña years of the recent past (1970, 1995, 2007, and 2010), 2020 was about about 0.5°F warmer than the next warmest year (2010). This means that more recent La Niña years (and El Niño years) are much warmer than they were in the past 70 years. Climate change is the main culprit for this, as greenhouse gases accumulated in the atmosphere and warmed up the planet over the decades.
The warming of our planet will continue as long as we emit greenhouse gases. While emissions briefly dipped in the spring during global shutdowns, they quickly resumed their upward course in much of the world. More record-breaking warm years are expected in the future, and in order to achieve a stable climate, we must reduce and keep our global carbon emissions low—permanently.
ED HAWKINS STRIPES
With the release of new global temperature data, Ed Hawkins has added a new 2020 stripe to his famous warming stripes pattern. With a temperature anomaly of +2°F, the new stripe will be a dark red, following the warming trend of the past decade.
New CO2 Charting Shows Speed of Recent Increase
Speed kills. The graph showing how much carbon dioxide levels have climbed since humans began burning fossil fuels may be the most iconic in climate science. But it doesn't tell half the story. With the help of neural networks, Climate Central scientists updated the classic analysis to show how fast CO2 levels have changed over the past 800,000 years. The result is a jaw-dropping skyscraper of a chart that shows how dramatic human influence has been. Visit the Capital Weather Gang/The Washington Post to see it and read more: https://www.washingtonpost.com/weather/2021/01/12/carbon-skyscraper-rapid-climate-change/
POTENTIAL LOCAL STORY ANGLES
How does the 2020 global rankings compare to the U.S. and other regions around the world?
2020 rankings for the U.S. can be found in our last Climate Matters post here. Information and rankings of other countries and regions are recorded in the NOAA 2020 Global Climate Report. The website also allows you to select specific months within 2020, and look at significant events that occurred around the world. You can access a 2020 map of temperature anomalies here.
What are the signs and impacts of climate change in your local area?
2020 was a year of record-breaking heat across the globe (especially in the Arctic), an unprecedented hurricane season, and raging fire season. For a quick overview on climate change and its signs and impacts, scroll through our climate change presentation, Our Changing Climate. Through our media library, you can also check out potential local warming trends with our decades of warming, 30-year temperature averages, and records set by decade graphics. You can explore impacts of climate change by reading through our latest seasonal packages (fall, winter, spring, and summer) or in our extreme weather toolkit.
LOCAL EXPERTS
The SciLine service, 500 Women Scientists or the press offices of local universities may be able to connect you with local scientists who have expertise on climate-related disasters in your area. The American Association of State Climatologists is a professional scientific organization composed of all 50 state climatologists.
NATIONAL EXPERTS
NASA and NOAA Scientists Available on January 15
A number of NASA and NOAA scientists will be available January 15th for one-on-one, 15-minute interviews from 6:00AM - 1:00PM EST. You can fill out this form to schedule a time slot: https://forms.gle/LMHA7o75adexoDkR6
*Spanish interviews availableGavin A. Schmidt, Ph.D.
Climate Scientist, NASA Goddard Institute for Space Studies
gavin.a.schmidt@nasa.govRussell S. Vose, Ph.D.
Chief, Climatic Analysis and Synthesis Branch
Climatic Science and Services Division, NOAA's National Centers for Environmental Information (NCEI)
russell.vose@noaa.govMaría José Viñas
Spanish Communications Lead, NASA Headquarters
Email to schedule Spanish-speaking interview: maria-jose.vinasgarcia@nasa.gov
METHODOLOGY
Calculations of average annual global temperature are performed independently at NASA and NOAA. Small differences in their calculations arise as NASA’s calculations are extrapolated to account for polar locations with poor station coverage, while NOAA relies more heavily on the polar station data. Climate Central compares temperatures to an earlier 1880-1910 baseline to assess warming during the industrial era. Calculations of 2016 and 2020 showed a virtual tie (2016: 1.263°C, 2020: 1.254°C). The “warming stripes” was conceived and calculated by Ed Hawkins, as described here.