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Hi gang. I am all new to GWB, and so these may be dumb questions. But here you go: Ocean chemistry is largely a function of carbonate chemistry. I am really struggling to get GWB to give me numbers that look like those I hand calculate for carbonate chemistry. Technically, one should only need two numbers from the following variable to calculate the carbonate system: alkalinity, pH, Total inorganic Carbon (TotC), pCO2 (or other spps. of carbonate). I am struggling to figure out how to set any two of these in GWB. I have tried setting HCO3- as a basis (so one variable is established...to 2 mmol/kg for example), and pH (to 8.1 for example). But the resultant alkalinity is nonsensical. And GWB also alters the [HCO3-]... which it should, considering it is using the HCO3- variable as TotC (I think...?) Also - is there any way to hardwire the SpecE8 output files to give alkalinity (or carboante alkalinity) in other units (mole equivalents, for example)? Someone else asked about this, but I was baffled by the answer. Thanks for any help to get going. I'm sure once I figure out the logic, I will have fewer problems! - Brian

I'm stuck on how to use Bicarbonate in GSS and making a Piper plot. My lab data comes in the typical form of: Bicarbonate (as CaCO3) mg/L Carbonate (as CaCO3) mg/L But there are no instructions on how to use the lab data in GSS. Firstly, there is no analyte called "Bicarbonate" so I assume I add it as a User define analyte, choosing mg/L as CaCO3 in the units column? Does this mean GSS/Gtplot will automatically calculate it as HCO3 (eg. divide by 50.04 (mg/meq))? Carbonate is more straight forward as it populates as Carbonate Alkalinity mg/L as CaCO3. Easy copy/paste from lab data into GSS. But does it also undergo a conversion to CO3? It would be really handy to see a GSS screenshot of the analytes/parameters list needed for a Piper plot. The video tutorial is not helpful in this regard as the complete list is not shown Thanks, Marie