Heat on Earth chases the sun, but with a lag and a tilt. Around the June solstice the sun is directly overhead at the Tropic of Cancer (23.5°N), so the band of the planet getting the most direct light all sits in the northern tropics. Average away the day-and-night difference between longitudes and what's left is a clean north–south profile of warmth — and its summit is north of the equator, not on it. The "thermal equator," the hottest line of latitude, migrates north in June and south in December. It almost never rests on 0°.
The starker number is the gap between the poles. Right now the Arctic is in a sun that never sets and the Antarctic in a night that never lifts, so at the same instant the far north can be tens of degrees warmer than the far south. Drag your cursor across the map: the warm flush isn't centred on the equator, it's smeared across the daylit, northern-leaning face of the planet. Brush the colour bar to isolate a temperature — pull the warm end and the great deserts light up; pull the cold and the only thing left glowing is the bottom of the world.