30 
Temperature difference WGHC Isopycllal - WGHC Isobaric at 500 m depth 
Salinity difference WGHC 
Isopycnal 
- WGHC Isobaric at 500 m depth 
90 
80 
60 
Longitude 
0.06 0.09 8.40 
Fig. 17b: Temperature and salinity differences for the depth 500 m between 
isopycnally and isobarically optimally interpolated data. 
Comparisons of our and the WOA01 climatology in 6-S space are presented in Fig. 15 for 
selected regions of the World Ocean for data below 2000 m (North Atlantic, South Atlantic, 
South Pacific, North Pacific). Along with gridded data the observed data from the high-quality 
dataset are shown. Following differences are worth to note: 
1) The WGHC climatology demonstrates tighter d-S sequences compared with the WOA01 
climatology, in a better agreement with high-quality data. 
2) The WOA01 climatology tends to ’’overestimate” salinity for the same potential 
temperature compared with observed data and the WGHC climatology. Thus, in the 
South Pacific Ocean the WOA01 salinity is about 0.005 higher compared with original 
data.