Galveston Bay and Coastal Ocean Optical-Geochemical Response to Hurricane Harvey From VIIRS Ocean Color

Dissolved and particulate organic carbon, suspended particulate matter concentrations, and their optical proxies colored dissolved organic matter absorption and backscattering coefficients were studied in Galveston Bay, Texas, following the extreme flooding of Houston and surrounding areas due to Hurricane Harvey (25-29 August 2017) using field and ocean color observations. A three-step empiricalsemianalytic algorithm for determination of colored dissolved organic matter absorption and backscattering coefficients revealed the dynamics of dissolved organic carbon and particle distribution from Visible and Infrared Imaging Radiometric Suite ocean color. Environmental drivers, especially floodwater discharge and winds, strongly influenced the spatiotemporal distribution of dissolved/particulate material in the bay and shelf waters following the hurricane passage. Over 10 days during/following the hurricane, similar to 25.2 x 10(6) kg C of total organic carbon and similar to 314.7 x 10(6) kg of suspended particulate matter were rapidly exported from Galveston Bay (representing similar to 0.65% and 0.27% of respective annual Mississippi River fluxes to the Gulf of Mexico), with potential for ecological impacts to shelf waters. Plain Language Summary Hurricane Harvey (25-29 August 2017), after making landfall on the Texas coast, deposited unprecedented rainfall (> 500 mm) that caused widespread flooding in the highly industrialized Houston Metropolitan and surrounding areas with potential for elevated levels of dissolved and particulate matter in the floodwaters discharging into Galveston Bay. We used a combination of field and satellite ocean color observations to examine the hurricane impact of Hurricane Harvey on the dissolved organic carbon and suspended particulate matter concentrations and their optical proxies in Galveston Bay and surrounding coastal ocean. Results of this study indicate that estimate of fluxes of material exported from Galveston Bay to the coastal waters over a 10-day period during/following Hurricane Harvey was similar to that exported by a large river.