Colorado's September 2013 Floods: What does surprise teach us about vulnerability in high adaptive capacity systems?

Theory and practice in the area of vulnerability and adaptation to weather and climate has rarely grappled with the topic of surprise. C.S. Holling defines surprise as “when perceived reality departs qualitatively from expectation.” Much effort has been expended to characterize and measure vulnerability and to develop indicators to track changes in vulnerability over time. However, little is known about how surprise affects the components of vulnerability, or perhaps surfaces new vulnerabilities. In September 2013, Colorado experienced an extreme flooding event that surprised many residents and public officials. Despite well-informed local governments, substantial planning efforts, and general awareness of the high risk flooding poses to the Front Range of Colorado, the state of Colorado experienced over $3B in losses and tallied 8 deaths from the event (NWS Service Assessment 2014). With the goal to better understand how incorporating surprise can update our theoretical and practical understanding of vulnerability, we conducted a pilot study to examine how residents were surprised by the Colorado floods in September 2013. In December 2013-March 2014 we included open-ended questions about what was surprising about the September 2013 Colorado floods in an online survey administered to residents of Boulder, Lyons, Estes Park and Longmont in Colorado's Front Range. Results indicate that the physical nature of the event was most surprising, followed by a smaller number of residents being surprised by their sensitivity, and fewer still surprised by adaptive capacity issues. In this presentation we will discuss how residents and public officials were (and were not) surprised by various aspects of the 2013 Colorado flood. We will also compare these results to previous work on perceptions of flood risk in expert and lay populations to further explore how surprises such as extreme events can better inform our characterization of population vulnerability. Using the findings, we will explore how surprises and perceptions of extreme event risks interact with adaptive capacity and vulnerability, and how knowledge about uncertainty in extreme events can be used to help build resilience. As part of building resilience, we will discuss how improved communication about risks prior to events help alter people's risk perceptions (“mental models” of extreme events) in a way that acknowledges the possibility or likelihood of surprises, enhancing their adaptive capacity, improving preparedness, and reducing vulnerability.