An NIU professor is trying to update a mathematical model that can accurately predict temperatures on a monthly basis for up to 100 years.

Associate Geography Professor Douglas ReVelle is examining a mathematical “recipe” created in 1987 by B.G. Hunt predicting monthly average temperatures. The model is 70 to 75 percent accurate for about 60 years, although ReVelle said the greatest range of records accurately used in the model were up to 99 years.

“I’m trying to understand the physical basis of what Hunt has produced,” ReVelle said. He then wants to improve the accuracy of the model although it is already more accurate than any previous model.

The Hunt model “is not based on the solution of the fundamental mathematical equations expressing conservation of mass, momentum and energy in the atmoshphere,” ReVelle said, but most theories to predict temperatures use these methods.

He said he wants to understand how and why the mathematical model works better than any of the physics models in temperature prediction.

ReVelle said areas of “Chaos” emerge in plotting average temperatures. Chaos is “an extreme sensitivity of a system to its initial state” that can cause temperatures to vary around the average, he said.

ReVelle said his next project with the model will include applying the model to precipitation levels.