Wind and ocean currents allow temperature in Earth to not be too extreme. Think of the Earth as a giant salad bowl and the currents as giant mixing spoons that you use to spread the salad dressing as evenly as possible. If not for wind and ocean currents, temperatures here on Earth will be too extreme (very hot in the tropics and very cold in the poles). Ocean currents from the equator deliver warm waters from the tropics and bring them to the poles. It also goes the other way: cold waters from the poles get circulated and gets warmer as they get near the equator. Of course, wind currents do the same thing. So you can see that currents are very important in regulating Earth's temperature.