Data Dive 4.2

Is every part of Earth warming?

The planet's average is going up. Does every region agree?

You will need paper and a pencil, and a browser for step 3

4.20 / 6Leave

Step 1 of 5 · Your guess

What do you think?

Earth's average temperature is rising. So a report says: every region is warming.

NASA splits the planet into 8 bands, like stripes from the North Pole to the South Pole, and tracks each one.

Write it down before you lookDo you think every band is warming at the same speed? Write yes or no, and why.
4.2 · Is every part of Earth warming?1 / 6Leave

Step 2 of 5 · Look

Every band of the planet, on one scale

Warming by latitude band, 1975-2025NASA GISTEMP zonal means - every panel on the SAME scaleanomaly, degrees C · shared scale -0.61 to 3.25064N-90N044N-64N024N-44N0EQU-24N024S-EQU044S-24S064S-44S090S-64S

NASA temperature records by band of latitude, 1975 to 2025.

How to read it. Each small chart is one band, from the Arctic at the top of the world to Antarctica at the bottom. Every small chart uses the same scale, so you can compare them.

Find out
  1. Which band is rising fastest?
  2. Is any band nearly flat?
4.2 · Is every part of Earth warming?2 / 6Leave

Step 3 of 5 · Try it

Now you try it, on the same data

This opens the pool, the site's chart tool. The words in bold below are buttons and menus you will see on the screen.

Do these five things

Open the pool on this file: data.sfhsbta.com/thepool?file=multiples_gistemp_zonal.csv&mark=line

  1. Under across, pick year. Under up, pick 64N-90N, the Arctic. Hover the first and last points. How much did it rise?
  2. Under up, pick 64S-44S, the ocean around Antarctica. Hover the ends. How much did it rise?
  3. Under up, pick global. Where does its rise fall between the two?
  4. Try each band. Which ones would you have to leave out to make “every region is warming” clearly true?
  5. Add one word to the claim so that it is true. Write it down.
4.2 · Is every part of Earth warming?3 / 6Leave

Step 4 of 5 · Say it

Your answer, in one sentence

I think the claim <is or is not true> because <what the chart shows> and I checked it by <what you did to the chart>.

The last part matters most. It shows you did not just look at the chart, you tested it.

Here is one exampleI think the claim is true for the planet but not for every band, because the Arctic rose 2.89 degrees while the band around Antarctica rose only 0.41. I checked by putting each band on the side and comparing the ends.
4.2 · Is every part of Earth warming?4 / 6Leave

Step 5 of 5 · What you found

Check your numbers

2.89
how much the Arctic warmed, in degrees C
0.41
how much the band around Antarctica warmed
46x
how much faster the Arctic is warming
The big idea: an average can hide disagreementThe planet's average is made of places that disagree. The Arctic is warming fast. The ocean around Antarctica barely moves, because deep cold water keeps rising to the surface there. A claim about the average is not a claim about every part.
One more thing to think aboutWhat other claim in the news says “every” but is really an average of things that disagree?
4.2 · Is every part of Earth warming?5 / 6Leave

After the dive

The charts you used today

small multiples

The same chart repeated once per group, so you can see whether the pattern holds everywhere.

What it leaves outEach panel is small, so only a large difference survives at that size. If the panels do not share one scale, they cannot be compared.
the line

A line follows one thing over time. Read it left to right and watch which way it leans — that lean is the whole story. A dashed stretch is a guess, not something anyone measured.

What it leaves outThe line implies every point between the dots, and nobody measured those. Where you start and stop it decides what the trend looks like.

library · ladder · dives · the pool · this dive’s worksheet

4.26 / 6Leave