There are two main geographical processes that are responsible for causing droughts. These are the atmospheric and hydrological pressures, and the El Nino effect.
The first geographical process that is responsible for droughts in Australia is the geography of the continent itself, and the atmospheric and hydrological pressures that are a result of this. These atmospheric and hydrological pressures mean that Australia has changeable rainfall patterns due to the high pressure systems that we often experience.
The dominance of high pressure systems along with a lack of moisture in the air, is one of the major reasons Australia is prone to drought.
The second and perhaps the most influential geographical process is the Southern Oscillation, a major air pressure shift between the Asian and East Pacific regions. This process is known as the El Nino effect. This major air pressure shift affects weather patterns in countries bordering the Pacific oceans. The El Nino Effect can cause severe drought conditions in Australia, such as the droughts in 1982-83, 1997 and in 2002-2007.
