We trained an empirical model to predict carbon system parameters from measured temperature, oxygen, salinity, pressure, and nitrate using data from P16S 2014 and S04P 2011 between 0 and 2100 m south of 45°S. We have applied these algorithms to floats in the Pacific Sector and evaluated the measured vs. the algorithm-predicted pH.

Graph of Float 9095 Measured pH
Float 9095 carbon data
Float 9095 surface pH scatter plot
Float 9095 measured pH data chart

For example:

pHN = β0 + β1*S + β2*T + β3*P + β4*N

pHOx = β0 + β1*S + β2*T + β3*P + β4*O2

Target Variable Predictor Variables R2 rmse
pHN
(pH units)		 Salinity
Temperature
Pressure
Nitrate		 0.981 0.010
pHOk
(pH units)		 Salinity
Temperature
Pressure
Oxygen		 0.964 0.008
DIC
(µmol/kg)		 Salinity
Temperature
Oxygen		 0.998 2.55
TA
(µmol/kg)		 Salinity
Temperature
Oxygen
Sigma Theta		 0.987 3.5
ΩAr
(no units)

Salinity
Temperature
Pressure
Oxygen
Sigma Theta

 0.993 0.024