Increasing atmospheric CO2 concentrations lead to an overall increase of CO2 concentrations in surface seawater and, consequently, a pH decrease – a mechanism called Ocean Acidification (OA). OA is well understood and traceable in the open ocean, where large-scale projects and actions supply an enormous amount of observations and experimental data and where the magnitude of OA is to a large extent thermodynamically consistent with the increase in atmospheric pCO2. In the coastal and shelf seas, OA is still a significantly understudied phenomenon despite their high socio-economic importance and potentially great vulnerability to acidification due to often lower salinity and corresponding lower buffer capacity of waters as compared to the open ocean. In the present study, we underline the importance of total alkalinity (TA) changes as the key factor shaping the OA dynamics, pH fields, and the variability in the aragonite saturation state in the coastal and shelf seas. The research extends from the brackish Baltic Sea to the Spitsbergen fjords affected by the high inflow of meltwaters. It revealed high variability in the marine CO2 system structure and significantly different effects of freshwater input to the investigated regions, from dilution to alkalinization. The observed overall spatial and temporal variability in TA extended in the broad range between <350 and 4,320 μmol kg-1. This makes TA a fundamental variable for studying the large-scale pH and pCO2 changes and forecasting the development of OA in the coastal zone in the future high-CO2 world.
Primary Presenter: Karol Kulinski, Institute of Oceanology PAS (kroll@iopan.gda.pl)
Authors:
Karol Kulinski, Institute of Oceanology PAS (kroll@iopan.gda.pl)
Fernando Aguado Gonzalo, Institute of Oceanology PAS ()
Laura Bromboszcz, Institute of Oceanology PAS ()
Magdalena Diak, Institute of Oceanology PAS ()
Katarzyna Koziorowska-Makuch, Institute of Oceanology PAS ()
Przemyslaw Makuch, Institute of Oceanology PAS ()
Izabela Palka, Institute of Oceanology PAS ()
Piotr Prusinski, Institute of Oceanology PAS ()
Seyed Reza Saghravani, Institute of Oceanology PAS ()
Alkalinity-driven changes of Ocean Acidification in the coastal zone
Category
Scientific Sessions > SS050 Disentangling Complex Long-Term pH and O2 Trends in Coastal and Estuarine Systems From Global and Regional Drivers
Description
Time: 06:30 PM
Date: 7/6/2023
Room: Mezzanine