The effects of Hurricane Harvey on Texas coastal-zone chemistry

Hurricane Harvey deposited over 90x109 m3 of rainwater over central Texas, USA, during late August/early September 2017. During four cruises (June, August, September and November 2017) we observed changes in hydrography and nutrient and oxygen concentrations in Texas coastal waters. Despite intense terrestrial runoff, nutrient supply to the coastal ocean was transient, with little phytoplankton growth observed and no hypoxia. Observations suggest this was probably related to the retention of nutrients in the coastal bays and rapid uptake by phytoplankton of nutrients washed out of the bays, as well as dilution by the sheer volume of rainwater and the lack of significant carbon reserves in the sediments, despite the imposition of a strong pycnocline. By the November cruise conditions had apparently returned to normal, and no long-term effects were observed.

Automated summary

Hurricane Harvey brought a huge amount of rainwater to central Texas in late August and early September 2017. Although there was intense terrestrial runoff, supply of nutrients to the coastal ocean was temporary and there was little phytoplankton growth and no hypoxia. The observations suggest that the nutrients were retained in the coastal bays and quickly taken up by phytoplankton, as well as diluted by the large volume of rainwater and lack of significant carbon reserves in the sediments despite the presence of a strong pycnocline. By November, conditions had returned to normal with no long-term effects observed.