Question

why do mountaineers usually suffer from nose bleeding at higher altitude

Answer 1

they suffer from nose bleeding because they are adjusted to high pressure and on mountains there is less pressure than plain so their internal pressure goes high which results in the bursting of veins and bleeding occurs

Answer 2

Mountaineers usually suffer from nose bleeding because at high altitudes less oxygen is available ..This makes the air dry and this makes our blood vessels exposed to the dryness as a result bleeding occurs....

hope this helps....