The Iowa Environmental Mesonet (IEM) celebrated its 25-year anniversary this summer! IEM helps farmers, researchers, meteorologists and everyone in between make informed decisions using weather and climate data. Daryl Herzmann is a systems analyst at Iowa State University and the person who creates the magic behind the scenes.
Back in 2001, IEM was created to help people understand publicly available weather data and environmental information. Over time, IEM has become and continues to grow into one of the state's most valuable weather resources. It provides access to observations from airports, National Weather Service stations, Iowa State University Research Farms, and other public monitoring networks. IEM does not collect its own data but instead pulls together information from trusted public sources and presents it in a way that is easy to understand and use.
One of the biggest challenges with weather data is making sense of it. Many datasets contain thousands or even millions of observations that would take a considerable amount of time to organize. The IEM uses automated plotting tools that allow users to generate charts, maps, and reports that can be used in presentations or articles without the hassle of uploading information into spreadsheets and creating graphs themselves.
Those tools have become especially valuable to those in Iowa's agricultural industry, where weather is a crucial part of decision making. Anyone can use the IEM to monitor precipitation, temperature, growing degree days, and long-term weather trends while comparing conditions across locations and seasons. Several IEM applications allow users to customize reports based on their own growing season.
Herzmann says, "Somebody that planted corn one year on April 10 and the next year they planted it on June 1, and so you want to be able to use those dynamically to generate plots." The website also helps users identify the most appropriate weather station for their specific needs. For example, airport weather stations often provide the most reliable wind observations because they are in an open space, as opposed to a more urban area. Choosing the right source matters because not every weather observation represents conditions the same way.
Although agriculture is one of the IEM's largest audiences, the website was designed to help anyone interested in Iowa's weather and climate. Researchers, educators, businesses, students and weather enthusiasts all use it to answer questions and monitor changing conditions.
As the Iowa Environmental Mesonet marks its 25th anniversary, Herzmann hopes users continue to explore its tools and ask questions when they need guidance. "Farmers know this already, that you go and talk to your neighbor with the same rain gauge, only different numbers. And they’re probably both right." Herzmann said.
The Iowa Environmental Mesonet has continued to make weather information more accessible and practical. By turning complex datasets into easy to understand graphs and maps, the IEM helps Iowans make better decisions every day.
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