The analysis could help researchers study storms that strike in the winter:
When a strong tornado roars through a city, it often leaves behind demolished buildings, broken tree limbs and trails of debris. But a similarly powerful storm touching down over barren, unvegetated land is much harder to spot in the rearview mirror.
Now, satellite imagery has revealed a 60-kilometer-long track of moist earth in Arkansas that was invisible to human eyes. The feature was presumably excavated by a tornado when it stripped away the uppermost layer of the soil, researchers report in the March 28 Geophysical Research Letters. This method of looking for "hidden" tornado tracks is particularly valuable for better understanding storms that strike in the winter, when there's less vegetation, the researchers suggest. And recent research has shown that wintertime storms are likely to increase in intensity as the climate warms (SN: 12/16/21).
[...] Swirling winds, even relatively weak ones, can suction up several centimeters of soil. And since deeper layers of the ground tend to be wetter, a tornado ought to leave behind a telltale signature: a long swath of moister-than-usual soil. Two properties linked with soil moisture level — its texture and temperature — in turn impact how much near-infrared light the soil reflects.
Wang and his collaborators analyzed near-infrared data collected by NASA's Terra and Aqua satellites and looked for changes in soil moisture consistent with a passing tornado.
When the team looked at data obtained shortly after the 2021 storm outbreak, they noticed a signal in northeastern Arkansas. The feature was consistent with a roughly 60-kilometer-long track of wet soil. Tornadoes had been previously reported in that area — outside the city of Osceola — so it's likely that this feature was created by a powerful storm, the team concluded.
That makes sense, Kingfield says, and observations like these can reveal tornado signatures that might otherwise be missed. However, it's important to acknowledge that this new technique works best in places where soils are capable of retaining water, he says. "You need to have clay-rich soils."
Even so, these results hold promise for analyzing other tornadoes, Kingfield says. It's always useful to have a new tool for estimating the strength, path and structure of a storm, but many storms go relatively unexamined simply because of where and when they occur, he says. "Now we have this new ground truth."
Journal Reference:
Jingyu Wang, Yun Lin, Greg M. McFarquhar, et al., Soil Moisture Observations From Shortwave Infrared Channels Reveal Tornado Tracks: A Case in 10–11 December 2021 Tornado Outbreak, GRL, 2023. (DOI: https://doi.org/10.1029/2023GL102984)
(Score: 3, Interesting) by DannyB on Tuesday April 11, @09:01PM (2 children)
The research is interesting. But also the human costs and lives affected.
Hopefully people can get federal assistance [arkansasonline.com] if needed. Even if it is decried as socialism. The damages sound bad from that story.
Tornadoes mostly cause people to think of Kansas even though other states are affected.
How often should I have my memory checked? I used to know but...
(Score: 4, Interesting) by Tork on Tuesday April 11, @09:27PM (1 child)
It's worse than that, more tornadoes are expected in more unexpected places. The more clues to their nature we pick up along the way the more lives we can potentially save with things like smartphone alerts. I've lived in several mid-west cities and it's easy to think the tornado is wherever you aren't. This is why I ache for more data.
Btw I hope the off-topic mod on DannyB's post was accidental.
Slashdolt Logic: "25 year old jokes about sharks and lasers are +5, Funny." 💩
(Score: 1, Funny) by Anonymous Coward on Tuesday April 11, @09:29PM
You must be new here.