by Cory Matteson | SNR Communications
To provide people with accurate data about rainfall, temperature, wind speed and more, climatologists in states across the nation lead strategic installations of research-grade weather stations across their states. Weather stations are finely tuned machines, expected to record key data within finite margins of error. But even high-tech systems need a tune-up once in a while, Nebraska State Climatologist Martha Shulski observes.
This past summer, the State Climate Office in the University of Nebraska–Lincoln’s School of Natural Resources began offering weather station sensor calibration services for research-grade equipment used in other states.
The State Climate Office stepped in to consolidate and streamline a calibration process that is often time-consuming, Shulski said. Four different companies manufacture the sensors on a typical U.S. weather station, she said, meaning a state office must send parts to multiple companies that often have backlogs.
The Nebraska program began with a shipment from the North Dakota Agricultural Weather Network, which sent a set of 17 temperature and humidity sensors from weather stations to Hardin Hall. There, in a basement lab, senior Nebraska Mesonet technician Glen Roebke ran the meteorological instruments through a battery of tests with instruments that can calibrate air temperature, humidity, barometric pressure readings and more.
The calibration center is an extension of the work the Nebraska State Climate Office has long performed for weather station sensors in its statewide Nebraska Mesonet weather-monitoring network, Shulski said.
“We’ve always calibrated our instrumentation in house,” Shulski said. “Now we’re opening up this service to other state weather networks. We’ve got the expertise. Glen has been doing this for roughly 20 years. He looked at what manufacturers do when you ship sensors to them for calibration tests and determined what we could replicate here in the lab. He looked at what other weather networks use for their sensors and equipment and developed techniques based on that.”
That effort led to the development of, among other tools, an indoor solar calibration table that is now located in the basement lab. Roebke previously only had a finite window of time to test the solar readings of the Nebraska State Climate Office’s pyranometers, which measure solar radiation.
“We’ve done a study in the past on when the best time of year to calibrate is, and the magic month is May,” Roebke said. “There are a lot of things that go into it. We want clear days, but there are a lot of clouds in the month of May, so it limits the number of days we can use it. And the other thing that’s a huge variable is temperature. Temperature affects how these instruments work. So we don’t want to do it in late July or the middle of August, because temperature changes the output. We want to stabilize it.”
Read more:
https://news.unl.edu/newsrooms/today/article/nebraska-state-climate-office-develops-weather-sensor-calibration-lab/