GCAN Webinar Series Presents: Dr. Xinping Hu & Dr. Leticia Barbero
Date: August 21st @ 1:00pm EST
Description: A five-year (2013-2018) time-series of the carbonate chemistry data (pCO2, pH, and carbonate saturation state) collected in surface waters at the Flower Garden Banks National Marine Sanctuary in the northwestern Gulf of Mexico (nwGOM) revealed variable temporal trends. pC O2 and pH showed significant positive (dpC O 2/dt = 5.0±1.1 μatm yr-1) and negative trends (dpH/dt = – 0.0040±0.0010 yr-1), respectively. Both trends were significantly greater than those observed in the open ocean. However, carbonate saturation states with respect to aragonite (Ωarag) did not exhibit statistically significant changes. The difference between these trends (or the lack of) may be partially due to the increase in sea surface temperature (0.25±0.09˚C yr-1), in addition to CO2 induced ocean acidification. In contrast,
significant decadal acidification (ΔpH ~ -0.1) in the subsurface waters (~50-250 m) w as observed in the broader nwGOM based on three separate cruises (2007, 2016, and 2017). Substantial accumulation of respirational CO2 along with atmospheric CO2 uptake may have both contributed to this acidification, but with many unknowns. We will discuss an upcoming project funded by the NOAA’s Ocean Acidification Program (OAP) that targets the ocean acidification problem in the nwGOM.
