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Related to altitude: altitude sickness
Etymology: L, altitudo, height
the level of elevation of any location on earth with reference to a fixed surface point, which is usually sea level. Several types of health effects are associated with altitude extremes, including a greater intensity of ultraviolet radiation that results from a thinner atmosphere. Barometric pressure decreases as altitude increases, so there are fewer molecules of oxygen. Thus breathing becomes faster & deeper, although demands of physical effort and cellular respiration are the same as at a lower altitude. High-altitude cardiac intolerance is usually worse in people with blood or pulmonary disorders. See also altitude sickness.
altitudethe height above sea level. As atmospheric (barometric) pressure decreases progressively with increasing altitude, from the standard 1 atmosphere at sea level, the partial pressure of oxygen (PO2) decreases proportionately; the air still contains the same ∼21% of oxygen but there are fewer molecules of oxygen per unit volume. There is also a drop in temperature and humidity, but the essential problem for human life and activity is shortage of oxygen (hypoxia).
n pertaining to any location on earth with reference to a fixed surface point, which is usually sea level. The higher the altitude, the lower the oxygen concentration and the greater the ultraviolet radiation, both of which can cause health problems.