Hi,

You can calculate pCO2 using any two of DIC, alkalinity and pH using the program CO2sys:  http://cdiac.ornl.gov/oceans/co2rprt.html. There are simpler versions but this program uses the two parameters plus pressure, salinity and nutrient information (if you have it) to calculate the other carbon system parameters.

I always use the MATLAB version and find it simple to use. You can also select which equilibrium constants you want.

Hope that helps!

Hi!

I can also recommend the CO2calc software http://pubs.usgs.gov/of/2010/1280/

It has similar features and is free and user friendly!

Best Regards,

Leon

Gnana, Nicola and Leon are absolutely right these work well. both CO2sys and CO2 calc are good.

The calculators mentioned above will do, but this is the standard reference for the theory:

http://cdiac.ornl.gov/ftp/oceans/Handbook_2007/Guide_all_in_one.pdf

thanks scientists for sharing of scientific information and help 

Seacarb is another great tool for CO2 system computations:

https://www.rdocumentation.org/packages/seacarb/versions/3.2

www.bioacid.de/upload/gattuso_seacarb_v1.pdf

It's a package to be used with the free statistical programming language R:

https://en.wikipedia.org/wiki/R_(programming_language)

wow...i really find this thread very informative, thanks for raising this question