Analysis of global surface ocean alkalinity to determine controlling processes

摘要: The export of calcium carbonate (CaCO3) from the surface ocean is poorly constrained. A better understanding magnitude and spatial distribution this flux would improve our knowledge carbon cycle marine biogeochemistry. Here, we investigate controls over total alkalinity in global produce a tracer for CaCO3 cycling. We took bottle data databases (GLODAP, CARINA, PACIFICA) subtracted effects several processes: evaporation precipitation, river discharge, nutrient uptake remineralization. remaining variation exhibits robust coherent pattern including features large amplitude extent. Most notably, residual more or less constant across low latitudes but shows strong poleward increase. There are differences ~110μmolkg-1 ~85μmolkg-1 between Southern Ocean subarctic North Pacific, respectively, but, contrast, little increase high-latitude Atlantic. This most likely due to production physical resupply deep waters. use corrections highlights errors that produced, particularly Bay Bengal Atlantic, if normalization assumes all salinities be caused by rainfall. can used as indicate where world's layer takes place, future changes calcification, instance acidification.