This uneven heating produces global circulation patterns. As the abundance of energy reaching the equator produces hot humid air that rises high into the atmosphere. A low pressure area forms at the surface and a region of clouds forms at altitude. Like local winds, global winds are caused by unequal heating of the atmosphere. Earth is hottest at the Equator and gets cooler toward the poles. The differences in heating create huge convection currents in the troposphere. At the Equator, for example, warm air rises up to the tropopause.