Expert and Public Preferences and Perceptions of Different Color Schemes and Map Overlays on a Tropical Cyclone Wind Exceedance Forecast Graphic

Abstract

Map graphics are often used for hazard risk communication, layered with numerical, verbal, and visual information to describe an uncertain threat. In the hurricane context, graphics are used to communicate the probability of different threats over a forecasting period. While hurricane graphics have been studied in the past, they have not been designed with colorblind-friendly accessibility and localization in mind. This study presents the results of a mixed methods study, testing the perceptions of different color schemes and map overlays on a wind exceedance map graphic with samples of experts (emergency managers and meteorologists) and the public. Nineteen experts from Florida and Louisiana were interviewed about their preferences for and risk perceptions of the design elements of the new wind exceedance graphic. The graphic prototypes were also tested using a public sample (n = 624) from Florida and Louisiana to study participants’ design preferences and risk perceptions. Both expert and public samples preferred a yellow-to-red scheme, though experts thought the yellow-to-red scheme presented the hazard as riskier and the public thought the reds-only scheme was riskier. Experts and the public preferred a map graphic with overlays; they scored a map graphic with overlays as riskier than a version without overlays. Understanding the connection between color scheme preference and risk perception for both experts and the public has important implications on risk communication as new graphics are designed. The conclusion of this study provides avenues for future research for experts who want to apply universal design aspects into hurricane graphics.