The rise of the Himalayas, since the Miocene collision of the Indian Subcontinent with Asia is clearly linked with the Monsoon cycle and the onset of ice ages.

Other plate tectonic factors are also involved, such as the almost-closure of the Australia-Sundaland gap and the development of a strong circum-Antarctic current.

But WHAT do we mean by the "rise of the Himalayas"?

The Miocene began 23 million years ago. The Himalayas are now at an average* elevation of 4-5 km

Let's say 4600m in 23 million years. That's 4.6 m in 23 thousand, 2 mm in 1 year.

Now. how much change has occured in the last Century? Millenum?

- about 3/5 of 5/8 of bugger-all - that's how much!

* (there are some VERY interesting issues about the heights of mountain peaks in the Himalayas getting higher since the late Miocene, due to the onset of glaciation, which erodes most strongly BETWEEN mountains, rather than rain which erodes everywhere.)