Added on: May 13, 2011
All pilots are properly taught that the standard environmental lapse rate is 2 degrees C per 1,000 feet. That is, the temperature aloft decreases by two degrees Celsius for every one thousand feet gain in altitude on average. However, it is a common practice by some pilots to erroneously use the standard lapse rate to estimate the freezing level based on the latest surface temperature. While this rule of thumb may work well in some instances, the actual lapse rate in the lower atmosphere on any given day will more often than not vary from the standard giving rise to the wrong freezing level. In this workshop, you’ll learn a much more accurate approach to estimate the current freezing level.