Khadadka waaweyn ee Dhulka

Muunaddan (model) ayaa kaa caawinaysa inaad baarto khadadka khayaaliga ah ee ku wareegsan Dhulka—sida dhul-barta (equator), kuleylaha (tropics), iyo wareegyada cirifka (polar circles)—oo ku salaysan jiidda meeraha iyo meesha ay ku yaalliin cirifyada.