How accurate are mathematical models at predicting when floods will occur and how severe they will be?
Luther College mathematics professor Richard Bernatz is spending his sabbatical studying those questions, along with two members of the Iowa Flood Center on the University of Iowa campus.
Bernatz says one of the reasons they are studying the Upper Iowa River basin upstream from Decorah is there is extensive rain gauge data set he has collected since the summer of 2004.
This rain gauge data provides the opportunity for a study of the relative accuracies of river flow calculations based on gauge rainfall data versus radar rainfall data.
The researchers are studying how to predict the Upper Iowa river discharge at various locations along the river channel, based on rainfall patterns in the Upper Iowa river watershed.
Additionally, Bernatz and Luther students have developed a rainfall simulation technique for studying the effects of a changing climate on the flow characteristics of the Upper Iowa River. Initial results were published in an article entitled "Flood Frequency Estimation by Neyman-Scott Rectangular Pulse Rainfall Model and TOPModel" in the Journal of the Iowa Academy of Sciences, volume 118, Issue 104.