The troposphere contains 75 percent of atmosphere's mass-on an average day the weight of the molecules in the air is14.7 lb..(sq. in.)- and most of the atmosphere's water vapor.ater vapor plays a major role in regulating air temperature because it absorbs solar energy and thermal radiation from the planet's surface. The troposphere contains 99% of the water vapor in the atmosphere. Water vapor concentrations vary with latitudinal position(north to south).
Proper is different from typical or average. Average mantel height is about 54 above the hearth extension. Proper depends on the fireplace size, required clearances and the aesthetic desired, which can vary widely. These are both proper mantel heights: This one's about 48 high.
Fireplace Andirons. Your fireplace, properly accented, is the visual focal point of the room as well as the center of your homeâs family and social life. Fireplace andirons, placed inside the firebox, are an important accent for a well-appointed fireplace. Decorative or Functional? When shopping for fireplace andirons itâs important to note the length of the shankâor âdogââthat the logs rest upon. At right, see an example of decorative andirons with short shanks. Andirons with 4-5 inch long shanks are purely decorative. They are made to go in front of a fireplace grate.