ΔE 7.6, close: similar, with a visible difference side by side. Desert Brown is more saturated, cooler than Earth.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Desert Brown is more saturated, cooler than Earth.
The same difference applies the other way round: Earth is more muted, warmer.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Earth on the colour wheel See Desert Brown on the colour wheel
All matches: Earth equivalents · Desert Brown equivalents