 
Summary: The MM5 vertical coordinate system
by Cristina Lozej Archer
Department of Civil and Environmental Engineering
Stanford University
California, USA
lozej@stanford.edu
30 April 2003
The MM5 vertical coordinate system is based on the definition of a
reference state, hydrostatic and constant with time. The reference state is
determined by a constant temperature profile defined as follows:
T0(z) = TSFC0 + A ln
p0(z)
p00
(1)
where three constants need to be defined. Sealevel pressure p00 is set
to 105 Pa. The constant reference temperature at pressure p00 (i.e., TSFC0)
is frequently set to 270, 280, 290, 300 K in polar, midlatitude winter, mid
latitude summer, and tropical conditions, respectively. The temperature
difference between p00 and p00/e (i.e., A) is usually taken as 50 K, but
should be extracted from typical domain soundings. Reference pressure
