In meteorology, precipitation types can include the character or phase of the precipitation which is falling to ground level. There are three distinct ways that precipitation can occur. Convective precipitation is generally more intense, and of shorter duration, than stratiform precipitation. Orographic precipitation occurs when moist air is forced upwards over rising terrain, such as a mountain. Precipitation can also fall in either liquid or solid phases, or transition between them. Liquid forms of precipitation include rain and drizzle.