Temperature Record 101: How We Know What We Know

  • Released Thursday, January 13, 2022

2021 was tied for the sixth warmest year on NASA’s record, stretching more than a century.

But, what is a temperature record?

GISTEMP, NASA’s global temperature analysis, takes in millions of observations from instruments on weather stations, ships and ocean buoys, and Antarctic research stations, to determine how much warmer or cooler Earth is on average from year to year.
Stretching back to 1880, NASA’s record shows a clear warming trend. However, individual weather events and La Niña — a pattern of cooler waters in the Pacific that was responsible for slightly cooling 2021’s average temperature — can affect individual years.

Because the record is global, not every place on Earth experienced the sixth warmest year on record. Some places had record-high temperatures, and we saw record droughts, floods and fires around the globe.

Universal Production Music: Knock and Wait (Instrumental) by Brice Davoli [SACEM], Well That’s Difference (Instrumental) by Jeff Cardoni [ASCAP], Wanna Be Hipster (Instrumental) by Jeff Cardoni [ASCAP], Curiosity Killed Kitty (Instrumental) by Robert Leslie Bennett [ASCAP], Eco Issues (Instrumental) by Max van Thun [GEMA]

Additional Footage: Pond5.com, CSPAN

Complete transcript available.

Vertical Version

This vertical version of the video is for IGTV or Snapchat. The IGTV episode can be pulled into Instagram Stories and the regular Instagram feed.


Please give credit for this item to:
NASA's Goddard Space Flight Center

Release date

This page was originally published on Thursday, January 13, 2022.
This page was last updated on Wednesday, September 13, 2023 at 9:06 PM EDT.


This visualization can be found in the following series: