loading page

Assessing Coastal Change Forecasts on the Louisiana Coast During the 2020 Hurricane Season
  • +1
  • Kara S. Doran,
  • Kirsten Jean Bendik,
  • Justin J Birchler,
  • Margaret Louise Palmsten
Kara S. Doran
United States Geological Survey

Corresponding Author:[email protected]

Author Profile
Kirsten Jean Bendik
Water Science Associates
Author Profile
Justin J Birchler
United States Geological Survey
Author Profile
Margaret Louise Palmsten
United States Geological Survey
Author Profile

Abstract

During hurricane season, the U.S. Geological Survey (USGS) forecasts the probability of coastal change prior to named storm landfall. Forecasts both quantify potential storm effects on the sandy coastlines and test our understanding of the drivers of coastal change. The forecasts can also be used to aid emergency response and management decisions in real-time. This study analyzed the skill of three USGS forecasts of coastal change, defined as the probability of collision, overwash, and inundation (PCOI) along the approximately 250 km of Louisiana coast from Hurricanes Laura, Delta, and Zeta in 2020. To test forecast skill, forecasts were compared with coastal changes identified in post-storm emergency response aerial imagery. Forecasts accurately identified areas where overwash and inundation were likely (true positive forecast ratios >0.75). Forecasts also produced an overly conservative estimation of overwash and inundation (false positive forecast ratios 0.56). High false positive forecast ratios for overwash and inundation may be the result of an overestimate in forecast extreme water levels.