Seasonal variability of carbonate chemistry and its controls in a subtropical estuary

Seasonal Controls of Seawater CO2 Systems in Subtropical Coral Reefs: A Case Study from the Eastern Coast of Shenzhen, China

“…As can be seen in Figure 5, unlike for the surface pH T and bottom Ω A , temperature showed a significant linear relationship with pH T , pCO 2 , and Ω A , with all data considered (n = 192), confirming the dominant role of seasonal changes in temperature on these CO 2 parameters (especially the pH T and pCO 2 ). Similar results have been found in other survey sites, such as the Patos Lagoon [61], Gulf of Mexico [62], Aransas Ship Channel [63], East China Sea [64], Northern South China Sea [65], and Pearl River Estuary [66]. Furthermore, based on the above linear relationship (i.e., temperature vs. CO 2 parameters), the seasonal variation in temperature, i.e., 17.9-34.5 • C, can be estimated to explain 11.6% (43.4%), 17.9% (44.4%), and 55.6% (3.3%) of the changes in pH T , pCO 2 , and Ω A of the surface (bottom) waters.…”

“…The water-mixing process can alter the concentration of TA and DIC in seawater, in turn, affecting the geochemical behavior of the CO 2 system [61,68,69]. Since salinity changes can effectively indicate the mixing process of different waters, the effect of water mixing on the carbonate system can be quantitatively (semi-quantitatively) revealed by fitting the relationship between the salinity and CO 2 parameters.…”