There’s a reason it’s so hard to remember which of these is which: we over-focus on the lines themselves rather than what they measure. Even if you look up a mnemonic for latitude versus longitude, you get stuff about the rungs of a ladder or the fact that longitude lines are all “long” (stretching between the poles) whereas latitude lines are of variables length.
This is ludicrous. We don’t try to remember the difference between width and height by thinking of which way the lines on a ruler point. We simply know what width and height are conceptually. Why don’t we do the same for latitude and longitude?
It might be that we find it harder to imagine “objective” axes of measurement on a spherical surface, but after all, Earth is not a featureless sphere just rolling around randomly. Its spin, counterclockwise from north, as well as its orbit around the sun (also counterclockwise from north), give it a consistent and objective basis for orientation. Think of the Earth as a spinning top, such that “up” is along its axis of spin. It doesn’t matter which way along that axis. No matter which hemisphere you live in, or whether you consider north up or down, the point is that we can all agree that the axis of up/down is north/south.
So, think of the north/south axis on the surface of the Earth as up/down, then think of the word we often use to measure up/down: altitude. This is just “latitude” with the first two letters swapped. Longitude is the other one (east/west).
As a bonus, you are now thinking of what latitude and longitude actually measure as coordinates, and not confusing the method of measurement with the subject of measurement.
L A T I T U D E
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