Nosebleeds can be caused by being up in a very high altitude. As you climb higher, the amount of oxygen in the air decreases. This makes the air thinner and dryer, which can in turn cause the inside of your nose to crack and bleed.F
Because as we climb higher the amount of oxygen in the air decreases and this makes the air thinner and dryer. And at higher altitudes the blood pressure inside of our body is more than the atmospheric pressure which forces the blood to come out from openings like the nose.
