Erosivity is a measure of the forces actually applied to the soil by the erosive agents of raindrop impact, waterdrops falling from plant canopy, and surface runoff.
	Erosivity has two parts.  The inherent erosivity determined by the rainfall at a location and the infiltration of the soil based on inherent soil properties.  The other part of erosivity is the part that management can change such as changes in infiltration that affects rate and amount of runoff and the present of material that reduces the forces applied to the soil.
	Erodibility is a measure of the susceptibility(inverse of resistance) of the soil to erosion.  Erodibility has two parts, the inherent erodibility of the soil and the part of the erodibility that can be influenced by management.
	Notice that most RUSLE2 factors contain both an erosivity effect and an erodibility effect.
	Erosivity is a function of climate and management.