Champaign, Ill. - Watching the sun disappear at midday during a solar eclipse is not only fascinating for viewers across the U.S., but the rare event also presents a unique opportunity for scientists to investigate weather-related changes in Illinois.
On August 21, Illinois State Water Survey researchers will use weather-monitoring stations and equipment in southern Illinois to capture subtle atmospheric changes before, during, and after the eclipse. Carbondale is the best location in Illinois to witness the longest duration of the total solar eclipse, which is expected to last 2 minutes, 37 seconds.
Four of the 19 stations of the Illinois Climate Network (ICN) are within the path of totality, or the location where a full solar eclipse can be seen. All stations will collect data at both 10-second and 5-minute intervals on air temperature, relative humidity, solar radiation, barometric pressure, and wind speed. Collected data across the state can be used for comparison, according to Jennie Atkins, program manager of the Water and Atmospheric Resources Monitoring (WARM) program, which includes the ICN. WARM is unique in the state in that it provides long-term records of weather and soil data from stations across Illinois.
“At the stations in the path, we expect to see declines in solar radiation and air temperatures within a certain period of time during the event,” Atkins said.
Atkins plans to analyze weather conditions from the data collected from about 9 a.m. to 5 p.m. that day. Researchers at other universities and organizations across the Midwest can collaborate on projects to understand how the eclipse changes weather conditions in Illinois and beyond.
So long as the weather is clear in southern Illinois, the ICN stations will be set to record this unique event. The last total solar eclipse that could be seen in the U.S. was in 1979, according to NASA.
“We have this rare opportunity and we don't want to miss it,” Atkins said.
ICN will live-stream updated weather data every 5 minutes at http://www.isws.illinois.edu/warm/eclipse/. The WARM website provides up-to-date water and atmospheric information in Illinois: http://www.isws.illinois.edu/warm/. Updates will also be provided on Twitter, @WARM_ISWS.
David Kristovich, head of the Water Survey's Climate and Atmospheric Science section is also anticipating the big event. Like Atkins, he considers the solar eclipse a chance to advance studies of atmospheric conditions. His research relating to atmospheric reactions to rapid changes in heating and cooling at the earth's surface could be used to improve the mathematical models used to predict the weather.
“We have studied slow changes in the atmosphere, such as when cooler conditions at night shift to warmer conditions during the day, but we have much less information on how the atmosphere responds to quick changes,” Kristovich said. “By collecting data during the solar eclipse, we can better understand these responses.”
Kristovich and his research team will be taking measurements at the Dixon Springs Agricultural Center from 12 hours prior to the eclipse to several hours afterward using Doppler LIDAR equipment to view the motions of microscopic dust particles, or aerosols, in updrafts and downdrafts in an occasionally turbulent atmosphere. The scientists will also launch a weather balloon carrying equipment that measures temperature, humidity, and changing winds in real time.
If the weather is cloudy that day, monitoring can still occur, but rain droplets block the smaller particles from sight. Rainy weather will shut them down, Kristovich said. However, researchers from other parts of the U.S. in the path of totality will be taking measurements that can be shared to further our understanding of the atmosphere.
-----
Jennie Atkins, Ph.D. - (217) 333-4966, jatkins@illinois.edu
David Kristovich - (217) 333-7399, dkristo@illinois.edu