Exploring the impact of Hurricane Harvey on the Carbon Cycle

Over the past several years, hurricanes and tropical storms have become more frequent and destructive. Hurricane Harvey, characterized as a category four, was one of the most devastating and destructive hurricanes along the Texas coast since Celia in 1970. Hurricanes cause severe impacts on the ecosystem, which substantially impacts the carbon cycle at the local or regional scale. During a hurricane, the loss of many vegetation/trees in the forest and agricultural lands causes more carbon to be released into the atmosphere. Studying the effects of a hurricane on the terrestrial carbon cycle, mainly gross primary product (GPP), net ecosystem exchange (NEE), and their interactions with land-use change, flood, and others are critical to understanding the impact on the terrestrial ecosystem. The main objective of this research was to evaluate the impact of hurricane Harvey on the carbon cycle and study the interactions among the flood events and terrestrial carbon cycling in the state of Texas using satellite measurements. This study analyzed the GPP and NEE distributions in the coastal climate zones in Texas using Soil Moisture Active Passive (SMAP) carbon products. Additionally, SMAP Carbon products (Res=9 km) were compared to the observed CO₂ flux data measured at EC flux site on the Prairie View A&M University Research Farm. Comparing SMAP's GPP and NEE before and after Hurricane Harvey, showed Texas to have a significant increase of carbon release and decrease of GPP during the hurricane. For example, 0.36 megatonne of carbon (MtC) was released on August 27, 2017, which was 30 times more compared to the amount of carbon released on the same day in 2016. Overall, the results showed that hurricanes contribute a net carbon source. This study helps to understand the impact of hurricane Harvey on the carbon cycle through spatial and temporal variations of carbon emission and uptake during the hurricane Harvey.