OSTEREXP.TXT    Ocean STERic EXPansion    2003/07/10

Changes in ocean surface height due to steric expansion between any
ocean states or monthly averages is calculated as the changes in ocean
surface height minus the ocean mass change divided by a constant
density of 1000 kg/m³.  This calculation of steric expansion is
consistent with Kirk Bryan's [1996, Eq. 3] "dynamic topography anomaly"
when integrated over the same vertical extent.

"Steric expansion" means a combination of thermal and haline expansion.
Because salt is nearly conserved globally, the global effect of haline
expansion is negligible.

Reference:  Russell GL, Gornitz V, Miller JR (2000) Regional sea level
changes projected by the NASA/GISS Atmosphere-Ocean Model.  Climate
Dynamics, 16: 789-797.

Model diagnostics available at:  http://aom.giss.nasa.gov/data.html
MOSI: Vertically integrated ocean mass plus sea ice (10³ kg/m²)
ZOS:  Ocean surface height (cm)

Calculation of ocean steric expansion:
ZOSTE (mm)  =  10 * ZOS - 1000 * MOSI

ZOSTE is a large negative number and should be used as a rate of change:
dZOSTE/dYEAR (mm/year)  =  [ZOSTE(2050) - ZOSTE(2000)] / 50
or as an accumulated change:
dZOSTE (mm)  =  ZOSTE(2050) - ZOSTE(2000)