Since satellites technically measure neither temperature nor the surface (where people live), it’s safe to say that ground thermometers are more accurate than satellite measurements.

Here’s why:

  1. Satellites measure the brightness of Earth’s atmosphere and then scientists work hard to convert that information to temperatures using computer models, which are simulations that help us better understand our planet’s complexities, like a laboratory in a computer.
  2. Scientists take brightness data from 16 different satellites. Imagine getting a box of puzzle pieces but with no reference picture to show you what the completed puzzle will look like. Experts deal with a similar challenge by taking information from all of those satellites that were launched in different decades since 1978 and figuring out how the pieces best fit together.
  3. Satellites measure the brightness of Earth’s atmosphere at different altitudes. For example, the layer of air measured closest to where people live is at the altitude where birds and airplanes fly. Scientists take and blend various measurements up to a height of nearly 23,000 feet (about 7,000 meters).