Dominguez-Giron, Tony2023-09-272023-09-272023-06http://hdl.handle.net/1773/50942The Western Pacific is a relatively unstudied area that is important for the climate because it is influenced not only by natural processes such as El Niño Southern Oscillation (ENSO) and seasonal variability but also the anthropogenic forces. The ocean's Dissolved Inorganic Carbon system (DIC), or carbonate system, is essential for how the ocean functions because of the complex air-sea interactions at the equator. The DIC system consists of the total carbon in the ocean that keeps the ocean's chemical balance in equilibrium. The changes in DIC were determined using measurements from three cruises from 2023, 2007, and 1993 with a similar transect along the Western Equatorial Pacific. Between 1993 and 2023, the ΔDIC in the 30 years was the highest near the equator (northward). This ΔDIC concentration was limited to mostly the upper 100 meters with a 200 𝜇mol/kg increase between 1993 and 2023. The most significant DIC increase was seen above the thermocline during each cruise. A quasi-linear relationship exists between the DIC concentration during each cruise and the respective atmospheric carbon dioxide measurement from Mauna Loa Observatory. This study concludes that despite the Western Equatorial Pacific being a region of air-sea flux of CO2 from the ocean to the atmosphere, the DIC values have continue to increase. DIC is also influenced by changes in air-sea gas exchanges that result from ENSO and seasonal variability during each cruise.Western Equatorial PacificDissolved Inorganic Carbon Systemcarbonate system