Anabatic winds are mainly created by ultraviolet solar radiation heating up the lower regions of an orographic area (i.e. valley walls). Due to its limited heat capacity, the surface heats the air immediately above it by conduction. As the air warms, its volume increases, and hence density and pressure decreases.

What causes an Anabatic wind?

During the day, the Sun heats such a slope (and the air over it) faster than it does the adjacent atmosphere over a valley or a plain at the same altitude. ... This warming decreases the density of the air, causing it to rise. More air rises from below to replace it, producing a wind.

What is Anabatic in geography?

From Wikipedia, the free encyclopedia. An anabatic wind, from the Greek anabatos, verbal of anabainein meaning moving upward, is a warm wind which blows up a steep slope or mountain side, driven by heating of the slope through insolation. It is also known as an upslope flow.