Assessing regional change and vulnerability

This poster lays out our efforts to "take the pulse" of the South Platte River basin, the first case study in the Western Water Assessment. Applying the template now well-developed in global change research, we first assess regional trends in population, economic development, and land use, while developing hypotheses about regional vulnerability to climate fluctuations. We illustrate these baseline trends in this poster. Given our interest in shorter-term climate variability, though, we add an effort to assess sensitivity to improved climate forecasts, which is often neglected in global warming studies.

The South Platte includes both urban and rural areas, though urban growth, fueled by a robust post-industrial economy, is the main development trend. To examine whether this makes the region more or less vulnerable to climate impacts, we first posit definitions of vulnerability, resiliency, absorptive capacity, and risk, and apply them to different sectors and at different scales for the study area. For example, urban water systems appear to have large absorptive capacity, because they have been planned using risk-averse principles. In short, urban systems are designed never to fail (they are robust). Because urban water often comes originally from agricultural supplies, net regional urbanization may make agriculture more vulnerable. However, many agricultural systems may be more flexible and resilient, that is, better able to recover from "failure." Indeed, we believe this tendency is heightened in an urbanizing area like the South Platte as agricultural water is sold to cities but leased back to farmers on an interruptible basis. Farming systems that cannot cope with supply interruptions, like orchards, either disappear or hold on to reliable supplies. Initially, it makes sense to suggest that robust systems are relatively insensitive to climate forecasts, yet our initial look at one urban system indicates that some of their robustness comes from flexibility-the existence of multiple sources, storage, and options in a seasonally-adaptable management plan. In this way, urban systems begin to demand more and improved climate information, and develop the potential for applying climate forecasts of a certain resolution and reliability. Details of this potential use in the region are examined in the accompanying poster on Western Water Assessment user studies.