When considering the processes and the factors influencing the development of landforms two scales must be considered. First is the regional scale of gross landform development (see below) relating to such aspects as overall relief, mountain elevation, plateau topography, overall drainage patterns and valley configuration. The processes involved are tectonics-driven internal processes and their interaction with climate-driven external processes. Both sets of processes operate at regional scales particularly the period from about 5 million to about 2 million years ago. The second scale is the local scale of detailed landform development (see further below) through the processes of weathering, erosion, transport and deposition. These processes are largely climatically controlled, operating within a context provided by the gross landforms. These processes operating especially over the last 2 million years to produce the landforms of today.