Number 34, June 2002

Student Editorial

Better Communication with Decision Makers: Focus on Forecasts

In the April 2002 WeatherZine student editorial, Tom Pagano questioned the sustainability of being an interdisciplinary scientist involved in both the physical and social sciences. As Tom pointed out, developing relationships with decision makers and understanding their world requires a lot of time that could otherwise be devoted to traditionally more respected and rewarded physical science research. Realistically, not all of us can, or will, devote collective months and years to understand how individual decision makers process information or manage risk.

What can we do, in a practical sense, to more effectively interact with decision makers without shifting from our careers in physical science? Roger Pielke Jr., in the August 2000 WeatherZine editorial, suggested we develop expertise that extends across a broad range of policy topics. I strongly agree with his identification of forecasts as one important cross-cutting area. Practically all resource management decisions make use of forecasts, even if only as implicit assumptions that the future will be much like the past.

So every time a forecast is issued or every time decisions must be made, we have an opportunity to influence how science is perceived and ultimately used. Our involvement can be as extensive as Tom's or as cursory as responding to a question at a meeting or over the telephone. Unfortunately, in my experience, even individuals with scientific training are contributing to confusion about forecasts. The following are areas where we particularly need improvement.

Interpret forecasts correctly. If misinterpreted, even perfect forecasts can be perceived as worthless - or worse. The uncertain nature of forecast products is not the problem. Instead, decision makers are often confused about the subject the forecasts refer to, as are too many scientists. For the seasonal climate outlooks issued by the National Weather Service's (NWS) Climate Prediction Center (CPC), the probabilities refer to the likelihood of conditions falling within each of three categories defined by the historic distribution of temperatures and precipitation occurring over 1971-2000. Too often, the forecasts are misinterpreted as indicating how extreme conditions will be, or simply as the chance of conditions being above or below "average" or "normal." In addition, probability anomalies are difficult for laypersons to understand. It is more effective to simply state the probabilities associated with each possible condition.

Jargon creates confusion. The terms "normal," "average," and "climatology" are used too casually. They seem too basic to require explanation, but their meaning differs according to a user's background and is often misconstrued. Are you, for example, referring to the expected value of seasonal total precipitation or the historical distribution (i.e., normal or climatological probabilities) of precipitation? Not only are the meanings statistically different, they provide different kinds of information to decision makers that will not be used in the same way.

Context is critical. Often, decision makers lack a good sense of the historical range of meteorological conditions for their region, especially concerning extremes. Simply providing a sense of historical conditions can be a great help to decision makers. Things get more confusing when dealing with specific forecast products. Are you aware that the seasonal climate outlooks issued by the CPC, the International Research Institute for Climate Prediction, and Canadian Meteorological Center each reference different historical periods? Statistically, the differences are small but it complicates communication with potential users.

Sometimes we simply don't know. While we are all aware of the limitations of our individual expertise, some scientists find it difficult to admit that meaningful forecasts are not always possible. CPC seasonal climate outlooks use "CL" to indicate that forecast techniques have insufficient skill on which to base a prediction. Decision makers appreciate acknowledgement of scientific uncertainty and can respond to it. In a broader sense, overselling scientific capabilities or future advancements can be detrimental in the long run, as decision makers are disappointed when performance doesn't live up to prior billing.

Don't confuse the role of researchers, forecasters, and decision makers. Scientists have the responsibility to conduct quality research, possibly targeted for specific applications and always communicated effectively. Forecasting agencies are responsible for issuing the best product possible. Experimental forecast products should be, but often aren't, clearly differentiated from official products that are based on techniques that have passed performance tests. It seems elementary to point out that decision makers are responsible for making decisions, but I know of cases where forecasters were pressed, and acquiesced, to advise what actions to take in response to potential threats.

Learn about "bad" products and science. Many decision makers express that they have difficulty differentiating between "good" and "bad" information. I have seen climate forecasts marketed by a private firm that were visually stunning, but incorrectly interpreted outlooks made by the National Weather Service's Climate Prediction Center (CPC). And decision makers have consistently asked whether Farmer's Almanac forecasts are better than NWS products. In a broader sense, many decision makers feel they are unable to distinguish between "good" and "bad" science. Because forecasts are perceived as not promoting any governmental agenda, they provide neutral ground for discussing other scientific topics. When I give talks to local-level decision makers, questions often come up about whether information and conclusions about other topics are correct or not, especially concerning climate change, ozone depletion, and air pollution. It pays to be well aware of these issues.

The bottom line is that forecasts provide each of us an opportunity to interact with decision makers. Effective interaction doesn't require that we each become interdisciplinary experts. By improving our involvement in a few areas, we can facilitate the informed use of advanced science.

Holly C. Hartmann
Department of Hydrology and Water Resources
University of Arizona, Tucson
hollyh@hwr.arizona.edu

Holly Hartmann recently received her Ph.D. in Hydrology and Water Resources from the University of Arizona, where she is now an Associate Research Scientist.