Estimating the height of the stable atmospheric boundary layer

The observed height of the atmospheric boundary layer (ABL) is compared to the heights of the stable boundary layer calculated using the formulae of Zilitinkevich and Mironov (1996) referred to as ZM96, and Kosovic and Curry (submitted), referred to as KC99.   The height was calculated from aircraft profiles flown during the 11 flights of the Coastal Waves 96 project.  The ABL height was defined as the height of the jet which was found at the top of the ABL.  Using the height of the inversion base gave similar results (not shown).

In the plots below, a perfect fit between the observed and calculated heights would fall on the strait line.
 
Observed heights from all flights compared to height from: Observed heights from selected flights compared to height from:
ZM96 equation 26 ZM96 equation 26
ZM96 equation 30 ZM96 equation 30
KC99 equation 34 KC99 equation 34

Agreement improved when flights with overall stable conditions were used (see maps of zeta below for each flights), or with data outside of flow accelerating around topography. Flights on June 11, 23, 29, and July 1, 1996 were chosen.

The best fit was found using the KC99 formula, which was close to the height from ZM96 equation 26, as this comparison between them shows.  Note that the height calculated from KC99 was found with the Monin-Obukhov formula for L which contained the Von Karman constant k, while the height from ZM96 defined L without k. A remaining question is how to account for the cross-shore slope of the ABL, which is in geostrophic balance across shore with the strong equatorwards flow. Should the cross-shore slope be removed, then compared to the formulae for the ABL depth?
 

How the height varies with zeta

How the height varies with cloud

Maps of zeta for each flight, to select which flights from which to calculate the stable BL height

zeta = z/L was calculated from  2 minute averages of fluxes from 30 m runs.
The columns indicate the survey region (see project map).
 
Point Conception Point Sur Cape Mendocino Cape Blanco
June 19 June 02 June 07 July 01
June 23 June 11 June 12
June 29 June 17 June 26
June 21

Please send comments or questions to me at kate@coast.ucsd.edu