Horse latitudes are where the tropics meet the mid-latitudes. The intertropical convergence zone is the one at the equator.
The difference is that the ITZ is often rainy because of the rising warm moist air, while the horse latitudes are often sunny because of the falling cool dry air. You’ll get becalmed and have to eat your horses in both places, though.
The calm belt might be based on real life horse latitudes where the wind barely blows: https://en.m.wikipedia.org/wiki/Horse_latitudes
Horse latitudes are where the tropics meet the mid-latitudes. The intertropical convergence zone is the one at the equator.
The difference is that the ITZ is often rainy because of the rising warm moist air, while the horse latitudes are often sunny because of the falling cool dry air. You’ll get becalmed and have to eat your horses in both places, though.