Award: OCE-2054935

This project took advantage of the busy hurricane season in 2020 for the Gulf of Mexico to determine how the passage of hurricanes changes the carbon flux from coastal waters and coastal wetlands. While most research investigate the direct impact of hurricanes, we examined what happens when the hurricane is further away but still generates a wind field of 20-30 mph at some distance away. We found the erosion rates of the coastal wetlands were, on average, 60 times higher from the daily average when a far away storm increased wind wave activity. This is an important consideration because these wetlands are storing lots of carbon in the soils and if far away storms can still cause erosion, then the carbon dioxide is released to the atmosphere. We also observed and modeled how carbon dioxide release increases from coastal waters when a hurricane passes by. There are two processes at work when that happens. The first is the water is stirred up, allowing carbon dioxide at depth to be released to the air or in the case of Hurricane Laura (2020) the phytoplankton growth was weakened, so instead of the carbon dioxide being taken up by these plants, it was released to the atmosphere. This research showed that for the coastal waters, there can be a short term release of carbon dioxide to the atmosphere due to hurricane passage but that for coastal wetlands, up to 800 years of stored soil carbon can be release to the water, with the vast majority released to the atmosphere. Last Modified: 07/05/2023 Submitted by: John R White