by The sudden, percussive cracking came as Barb Berlin was standing in the garage of her farmhouse near Inman, Nebraska.
“I thought it was a gun,” she said.
Then came a white streak. She realized that the sound was not gunfire but hail.
A medium-sized hailstone hit the tin roof of a Berlin garage. Soon, others were leaving softball-shaped craters in the hood of their Ford Mustang, which was parked outside.
“It was so loud it was scary. I did a lot of praying,” Berlin said, adding that she was worried about her livestock. “I’ve never heard anything like that before.”
Hail is a sneaky hazard. This year, amid a spring and summer of extreme weather, hail — not hurricanes, floods or tornadoes — caused the highest damage costs in the US, according to Gallagher Re, a global reinsurance firm that tracks such data.
And research suggests that large hailstorms like the ones seen in Berlin on Monday will become more common as the Earth warms. That was the finding of a study published last month, which suggested that the likelihood of smaller, less damaging hail will decrease.
The study by Northern Illinois University researchers predicts that the frequency of hail around 1½ inches or more will increase by 15% to 75%, depending on how much greenhouse gas pollution humans emit.
A head is generated when thunderstorms disperse raindrops into the upper layers of the atmosphere. It usually forms where the temperature is between minus 22 degrees and 14 degrees Fahrenheit. The reason climate change affects rocks is because higher temperatures provide more energy to create upward air pressures within thunderstorms.
“We see stronger updrafts in the future because we have more atmospheric instability,” said Victor Gensini, lead author of the study and professor of meteorology at Northern Illinois University.
These powerful upgrades allow hailstones to stay longer in parts of a storm that are favorable for hail formation, the research says. As a result, they will accumulate more ice before they become too heavy and fall to the ground.
“Imagine taking a hair dryer and turning it on end and pointing it up at the sky and trying to balance a ping pong ball,” Gensini said, explaining how the updraft lifts hailstones. “Now try balancing a baseball or a grapefruit. You’re going to need a much stronger upgrade to balance that downward force.”
The prospect of more hail, already one of the costliest weather hazards in the United States and a major factor in driving up insurance premiums, will only intensify those issues.
“Storm losses are a really big piece of why premiums keep going up and why there’s this massive reassessment of risk not just by the insurance industry, but by banks and the federal government,” Steve said. Bowen, chief scientific officer of Gallagher Re. .
He added that hail accounts for about 50 to 80% of insured claims filed from storm-related losses.
So far this year in the United States, thunderstorms have been responsible for about $61 billion in economic losses, according to Bowen. Hail was probably responsible for between $31 billion and $49 billion of that total. In the same period, tropical storms and floods combined accounted for $14 billion in losses.
The atmospheric dynamics associated with blizzards are complex and can be difficult to study, but advances in climate and weather modeling now allow scientists to create complex simulations that model thunderstorms and their microphysics, with hail size is included.
For their study, Gensini and his fellow researchers took future climate projections and fed them into a weather model, not unlike what TV forecasters use.
The study predicts hail in the Plains states, but more severe hail overall, and in other regions.
While a warmer atmosphere allows more melting as hailstones fall to the ground, that dynamic is most affected by smaller stones, which descend more slowly.
The terminal velocity of a baseball-sized piece of hail is about 100 mph, according to Harold Brooks, senior research scientist at the National Oceanic and Atmospheric Administration’s National Severe Storms Laboratory, who was not involved in the recent study. In contrast, a 1-inch piece of hail falls at 20 to 30 mph.
He said the results of the study have been traced to previous work. A 2017 study used a different modeling approach and predicted more hail on average but fewer hail days. Meanwhile, researchers in Italy assessed more than a million hailstones from 1988 to 2016 and suggested that storms were producing fewer hailstones and more.
“It makes sense. We’ve gotten some clues from the observations,” Brooks said. “The underlying physical mechanisms they’re talking about are not surprising at all.”
Although hail causes more damage per year than tornadoes, on average, research on the former had stalled until recent advances in radar and weather modeling.
“It’s not as sexy as tornadoes,” Brooks said.
He added that key questions about hail remain: “Can we learn enough about how hail forms, and what is the distribution of hail sizes during a storm to make actionable forecasts several hours in advance?” “
Next year, Gensini and scientists from several other institutions are planning the first U.S. field study of stoneflies since the 1970s. The researchers will search for large storms like some of them tornadoes and try to deploy mobile Doppler radars and other instruments to capture the internal physics of the storms.
After Monday’s storm in Nebraska, Berlin said she saw several roofing company trucks rolling through town. An insurance adjuster has already assessed her roof for damage. His Mustang suffered approximately $3,500 in damage.
With more notice, she said, she would have kept her animals safe and put her car in the garage — she didn’t get a snow warning in the forecast, and only got a weather app alert after the storm to be gone.
Fortunately, Berlin said, “none of the livestock was injured, but it was big enough that it could have done a lot of damage.”
This article was originally published on NBCNews.com
