Ocean Acidification at a Crossroad– Enhanced Respiration,Upwelling, Increasing Atmospheric CO2, and their interactions in the northwestern Gulf of Mexico”

Xinping Hu, Texas A&M University-Corpus Christi

Among the NOAA designated Large Marine Ecosystems, the Gulf
of Mexico (GOM) remains poorly understood in terms of its current OA conditions, despite its
ecological and economic significance. In the northwestern GOM (nwGOM), decadal
acidification has been observed in the shelf-slope region, with metabolic production of CO2
contributing to a larger fraction of CO2 accumulation than uptake of anthropogenic CO2, and the
observed rate of acidification is significantly greater than that in other tropical and subtropical
areas. Unfortunately, whether the observed OA in this region represents a short-term
phenomenon or a long-term trend is unknown.
It is hypothesized that increasing atmospheric CO2, increasing terrestrial nutrient export
due to an enhanced hydrological cycle, and enhanced upwelling due to climate change will cause
the continental shelf-slope region in the nwGOM to acidify faster than other tropical and

subtropical seas. In order to test this hypothesis wave gliders, in -stiu sensor along withe underway measurements from research vessels will measure carbonated chemistry in in surface and shallow  waters. Modeling will be used tp integrate the chemical signals into the models to hindcast/predict spatia; and temporal variation of the OA signal for the the optimization of monitoring design and implementation.

Tuesday, March 3, 2020