Carbonate chemistry trends in the northwestern gulf of Mexico

Humans over the years have contributed to the changes in sea water chemistry. These changes stem from human caused carbon dioxide (CO2) releasing activities related to burning of fossil fuels, cement production, and land use changes associated with agricultural activities among others. From the beginning of the industrial revolution atmospheric CO2 has increased from 280 ppm to the current 419 ppm. In the same period, global oceans have taken in 30% of the global emissions as dissolved CO2 therefore playing a role in climate change mitigation. Increase in dissolved CO2 causes ocean acidification (OA). In the northwestern Gulf of Mexico (nwGOM), a decadal acidification has been observed in the shelf-slope region. For coastal areas the short term and long-term changes in the carbonate chemistry vary by location and can be influenced by river input, water stratification, ocean currents, and biogeochemical processes (photosynthesis, respiration, carbonate formation and dissolution). Despite its ecological and economic significance, the Gulf of Mexico and its current OA conditions are still misunderstood. This preliminary master’s thesis research will focus on spatial and temporal changes of carbonate chemistry trends of the nwGOM with a goal to understand the regions carbon dioxide sequestration over the past 5-10 years. Open access data from the Gulf of Mexico and East Coast Carbon (GOMECC) cruises-2007, 2012, 2017 and 2021 have been employed to explore this question. These expeditions have supplied comprehensive measurements of all primary inorganic carbon system parameters in these coastal waters. In addition, automated devices such as gliders equipped with sensors also collected additional measurements.