Geomorphology is a branch of physical geography. It can be defined as the science of landforms with an emphasis on their origin, evolution, form and distribution across the physical landscape. It is the scientific study of the nature and origin of landforms created by processes occurring on the surface of Earth.
Of all natural hazards, the most insidious is drought. However, for some countries such as Australia and United States, droughts have not led to starvation, but to spectacular fires as tinder-dry forests ignite, grasslands burn and eucalyptus bushland erupts in flame. Fire hazard is the most common hazard, which is present in all areas of life. Most combustible materials are stored in a normal atmosphere, which contains oxygen, and so the risk of fire is then due to the possibility of an ignition source. Fire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. Three elements are required to start and sustain fire: (1) oxygen, (2) fuel, and (3) heat. To start a fire, source of ignition such as a spark, flame and high temperature are needed. Diagram for understanding the necessary ingredients for most fires. The fire extinguishes by removing anyone of the elements in the fire triangle