Barometric Step

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Barometric Step

 

pressure step, the difference in altitude between two points along the same vertical, expressed by the difference in atmospheric pressure, measured in units of 1 millibar (1 millibar = 100 newtons per m2). The barometric step increases with decreasing pressure. Therefore, it increases with increasing altitude. At sea level, at a standard pressure of 1,000 millibars and air temperature of 0° C, the barometric step is close to 8 m for every millibar. At an altitude of 5 km, where the pressure is approximately twice as low as at sea level, the barometric step is approximately 15 m for each millibar. The barometric step increases by 0.4 percent for every degree of temperature rise. The barometric step is used in barometric leveling.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.