Yes, in a very localized way.
ALL erosion by definition is the reduction of structure to smaller pieces. Thus, it will always result in a reduction of any structural altitude on the affected body. However, it is but one of many interacting forces in the environment.
While erosion rates may be affected by changing climatic conditions, the rate of altitude decrease by erosion does not have an impact on climatic conditions.
Altitude is a very local measurement. It is not homogeneous across the planet. Compared to the height of the atmosphere and depth of the oceans, ground altitudes are relatively insignificant.