T _e [S III]–T _e [O III] trends measured in z ∼ 0 extragalactic H II regions (gray diamonds; see Section 3) and dwarf galaxies (blue squares; see Section 3) and in D40 (green circle) at z ∼ 3. The Garnett (1992) photoionization model T _e [S III]–T _e [O III] relation is shown as the solid red line; the empirical scaling relation of Rogers et al. (2021) is provided as the solid blue line. The dotted line represents equal T _e [S III] and T _e [O III]. The T _e measured in D40 agree with the T _e trends of local ionized regions and the empirical T _e –T _e scaling relation.