In the classic Gill-type response of the tropical atmosphere to localized equatorial heating, the forced response consists of an eastward-propagating Kelvin wave and westward-propagating Rossby waves: the Kelvin wave propagates directly along the equator to the east of the heat source at a considerably faster phase speed than the Rossby waves, which propagate to the west of the heat source (typically manifesting as a pair of off-equatorial cyclonic gyres); because Kelvin waves propagate eastward, they are located to the east (not the west) of the heating source, while Rossby waves, propagating westward, are located to the west (left, in a standard west-to-east oriented view) of the heating source.