Drought Decision Analysis

The Drought Decision Problem

Drought emerges slowly and may endure over multiple years. And at the start the decision-maker is faced with uncertainty: Is this going to be a deep drought? Will it last into next year, or the year after that? When is it time to start taking drought response actions? How aggressive of a response is called for?

Such decisions have an awkward structure: Some choices must be made now, before the full potential of drought is clear. Later it might not be possible to top off reservoirs, lease the snow-making water, or plant an alternative crop. But the costs incurred now may not pay off if the drought does not worsen, and decisions may cause unnecessary loss: unhappy rate payers, lost farm income, or wasted investment. On the other hand, if the drought lingers and worsens, the decision-maker will face a different set of regrets if they choose to do nothing: Rate payers may be miffed at modest cut-backs now, but will surely be angry at steeper cuts next year.

In these ways the drought response decision is like most decisions made under uncertainty, and tools exist to help with such decisions. Drought is different from some weather and climate related decisions such as whether to evacuate a city in front of a hurricane, activate the orchard’s frost protection systems, or to call in the full snowplow staff overnight in the face of a winter storm forecast, mainly in terms of the time frame of the choices. But, like those other decisions under uncertainty, drought response follows and arc of: judging the options, weighing possible outcomes, and considering the regret costs of decisions made or not made.

Risk and decision analysis tools can help with such decisions. The formal process for analyzing and making such decisions is most well developed in water resources where best-practice templates and tools are available and widely used. In many other drought-sensitive endeavors, decision-makers cope with uncertainty in various ad hoc ways. In some cases they face a single choice: lease the extra water or not. In others, the choices evolve along with the drought, the season, and the budget available, some options foregone as the season and drought progresses, others newly emerging.

Current Drought Decision Analysis Projects


The Climate Adaptation Decision Models team includes: Bill Travis, Adam McCurdy, Joseph Tuccillo, Trisha Shrum, Angela Korneev, Bryce McGuire, and Travis Williams.

For information about the Ranch Drought project, contact: william.travis@colorado.edu
For information about the R-DRIR simulation tool, contacts: trisha.shrum@colorado.edu