The Cause of Warm, Dry Conditions On The Lee Side
The condition exists because warm moist air rises through "orographic lifting" up and over the top of a mountain range or large mountain. Because of decreasing atmospheric pressure with increasing altitude, the air expanded and adiabatically cooled at the dry adiabatic lapse rate to the point that the air reaches its adiabatic dew point (which is not the same as its constant pressure dew point commonly reported in weather forecasts). Upon reaching the adiabatic dew point, water vapor in the air begins to condense, with the release of latent heat from condensation slowing the overall rate of adiabatic cooling of the air to the saturated adiabatic lapse rate as the air continues to rise. Condensation is also commonly followed by precipitation on the top and windward sides of the mountain. As the air descends on the leeward side, it is warmed by adiabatic compression at the dry adiabatic lapse rate. Because the air has lost much of its original water vapor content, the descending air creates an arid region on the leeward side of the mountain.
Read more about this topic: Foehn Wind
Famous quotes containing the words dry, conditions, lee and/or side:
“Then I had only prisoners’ thoughts. I awaited the daily walk which I took in the yard, or my lawyer’s visit. I managed the remainder of my time very well. I have often thought that if I was made to live in a dry tree trunk, without any other occupation but to watch the flower of the sky above my head, I would have gradually gotten used to it.”
—Albert Camus (1913–1960)
“The Settlement ... is an experimental effort to aid in the solution of the social and industrial problems which are engendered by the modern conditions of life in a great city. It insists that these problems are not confined to any one portion of the city. It is an attempt to relieve, at the same time, the overaccumulation at one end of society and the destitution at the other ...”
—Jane Addams (1860–1935)
“Surely tis by faith we are upheld thro such trials—justice will be meted in time to those who fill soft places and malign men who perform heroic duties—”
—Elizabeth Blair Lee (1818–?)
“... the hey-day of a woman’s life is on the shady side of fifty, when the vital forces heretofore expended in other ways are garnered in the brain, when their thoughts and sentiments flow out in broader channels, when philanthropy takes the place of family selfishness, and when from the depths of poverty and suffering the wail of humanity grows as pathetic to their ears as once was the cry of their own children.”
—Elizabeth Cady Stanton (1815–1902)