Hydrologic Extremes and Society
Chair: Hilary McMillan (San Diego State University)
This session focuses on observations, prediction, communication and adaptation to hydrologic extremes. By bringing together ideas from flood and drought research, we analyze similarities and differences in societal impacts and interactions with these two extremes. We explore how providing observations and information about hydrologic extremes can change the way societies understand and react to crisis events.

"Tracking Drought Impacts Across Space, Time, Sectors and Scales"
Speaker: Kelly Smith (University of Nebraska Lincoln)

In the 1990s and early 2000s, drought disaster researchers called for creation of a comprehensive database of drought impacts. But creation of such a database presumes that there is a single perspective from which all impacts will be visible. In fact, drought impacts are like fractals – as you focus on smaller scales, new realms of detail become apparent. An individual farmer’s drought-related loss or the hardship that an agricultural community experiences may be completely lost when drought impacts are aggregated to a national scale. Furthermore, drought impacts occur within specific contexts – a household has to water landscape and garden plants more; a reservoir operator produces less hydropower; fish die because a river dried up; fewer lift tickets are sold when there is no snow; and so on. Decision-makers in each of these sectors may or may not consider drought – an abstraction, often one of many pressures – as causing a separate impact, and they typically describe its effects, nested within a context that includes both long- and short term institutional effects. And many people have the adaptive capacity to foresee and prevent losses – a ski resort may offer hiking opportunities instead – so lack of water does not always translate into a drought impact. While this may seem obvious, it means there is no common framework for identifying, let alone quantifying, drought impacts. Sector and scale both matter. Large-scale commodity crops and hydropower production are some of the easiest drought impacts to quantify. Health effects to individuals and ecosystems are some of the hardest. Data collection requires resources, and in the absence of unlimited resources, we need to determine what data needs to be collected – or analyzed – to manage drought impacts.