Retrospective and Prospective Evaluations of Droughts and Floods among Residents along the U.S. Gulf Coast

The United States’ fourth National Climate Assessment sends a clear and urgent message to the nation that climate extremes will intensify and become more frequent. The U.S. Gulf coast region, with the concentration of population and energy-related infrastructure, is susceptible to the impacts of climate extremes. Severe coastal flooding is projected to become more frequent and widespread. This region has recently experienced large amounts of economic damages caused by high impact events including Hurricane Katrina (2005), Louisiana flood (2016), Hurricane Harvey (2017), Hurricane Irma (2017), and Hurricane Michael (2018). Meanwhile, drought has been usually ignored in this region but could pose serious risks once it occurs. By using a 2019 Gulf Coast survey combined with PRISM data, we examine the retrospective and prospective evaluations of drought and flood trends among coastal residents in this region. Drawing upon psychology and political science literature, we are particularly interested in how the objective conditions of past floods and droughts influence individual perceptions of these hazards and how their retrospective evaluation affects their prospective evaluation of future trends of these hazards. We find that coastal residents’ retrospective evaluations of past droughts and floods are significantly influenced by historic objective conditions. Specifically, individuals’ perceptions of the past trend on drought number are positively related to drought frequencies. Whereas, their perceptions of the past trend on flood number are negatively correlated with flood frequencies. Furthermore, the intensity rather than duration of the objective conditions affects one’s judgement on the past trend of drought duration and flood amount, respectively. Their retrospective evaluations highly significantly affect their prospective evaluation of future trends of these hazards. Moreover, those who rely on a longer time span in reference to the future are more likely to perceive increasing trends of drought and flood in the future.By deepening our understanding of how the objective hydrological conditions shape perceptions of drought and flood, this study can contribute to a growing field of the integrated social-hydro system.