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Posts Tagged ‘hail

“You have to be in the right place at the right time. Or the wrong place at the wrong time, depending on your perspective”*…

 

Hailstones

 

Hailstones are balls (or spikes, or flattish pancakes) of frozen precipitation that measure at least 0.2 inches across, according to the National Oceanic and Atmospheric Administration’s Severe Storms Laboratory. Several other types of smaller frozen precipitation are known as “ice pellets,” reports the National Snow & Ice Data Center, and may take the form of graupel (soft balls of water droplets clinging to a snow crystal and looking like Styrofoam) or sleet (essentially icy raindrops). In the sky, either of these can serve as an “embryo,” the little nucleus around which a hailstone can grow. The longer a fledgling hailstone stays lofted in a thunderstorm’s fierce updraft, the bigger it gets. Beyond that minimum 0.2-inch threshold, there are a few finer distinctions between hailstones, thrown around by researchers and sometimes forecasters at the National Weather Service. “Severe” hail has a maximum dimension of one inch or more, “significantly severe” stones are larger than two inches, and “giant” hail is bigger than four inches.

“Giant” sounds pretty big, but this crop of researchers didn’t think it seemed quite big enough. A hailstone of more than four inches is “certainly very large,” says Matthew Kumjian, a meteorologist at Penn State University and lead author of the paper. But, he adds, while stones of that size are rare, “they are not exceptional.” Hailstones bigger than four inches are reported 30 to 40 times a year in the United States alone, he says. Stones larger than six inches, though, are few and far between. Kumjian’s co-author, graduate student Rachel Gutierrez, combed through reports and found about 10 confirmed instances in the last 10 or 15 years, mostly in the U.S. (There were a handful of unconfirmed reports in Australia, Africa, and Asia, but photos or official measurements were missing.)

The researchers suspect that there are probably more of these spectacularly sized hailstones dropping down across the country, but they’re likely going unnoticed. When measuring hail, time is of the essence: Hailstones vanish fairly quickly, especially in hot or humid conditions, or if they shatter on impact; even large ones with cushioned falls might be overlooked. The most severe hailstorms in the United States are in the Great Plains, Kumjian says, where people are spread fairly far apart…

They’re huge; they’re rare; and they’re melting all the time: “The Slippery Problem of Measuring Enormous Hunks of Hail.”

* Matthew Kumjian, a meteorologist at Penn State University, on measuring hailstones

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As we check the weather, we might recall that it was on this date in 1883 that the volcano on the Indonesian island of Krakatoa began to release huge plumes of steam and ash. Roughly three months later, on August 27, it erupted in earnest– with a sound so loud that it circled the earth four times.  (As big as the explosion was, it was not the biggest in history: experts suggest that Santorini’s eruption in 1628 BCE was three times as powerful.)

300px-Krakatoa_eruption_lithograph source

 

Written by LW

May 20, 2020 at 1:01 am

“Enter RUMOUR, painted full of tongues”*…

 

ftd-logo

 

FOIA The Dead is a long-term transparency project that uses the Freedom of Information Act (FOIA) to request information from the FBI about the recently deceased.

That law requires certain government agencies to produce records upon a request from the public. One significant exception to that requirement is that, to protect the privacy of individuals, federal agencies may not release information about living people. But after their death, their privacy concerns are diminished, and those records can become available.

FOIA The Dead was founded to address that transition. When somebody’s obituary appears in the New York Times, FOIA The Dead sends an automated request to the FBI for their (newly-available) records. In many cases, the FBI responds that it has no files on the individual. But in some cases it does, and can now release those files upon request. When FOIA The Dead receives it, the file gets published for the world to see…

A project of the Freedom of the Press Foundation, written and maintained by Parker Higgins, FOIA the Dead is here.

* Shakespeare (stage direction:  Henry IV, Part 2)

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As we look to our legacies, we might recall that it was on this date in 2010 that the largest hailstone in (recorded) U.S. history fell in Vivian, South Dakota.  Weighing 1 lb 15 oz, it was 8.0 inches in diameter (18.6 inches in circumference. It broke the former U.S. record set on 3 Sep 1970 in Coffeyville, Kansas by a stone weighing 1 lb 11 oz that had a 5.7 inch diameter.

A larger hailstone– 2 lb 4 oz– is said to have fallen in Bangladesh on April 14, 1986 in a hailstorm that killed 92 people.

hailstone

The Vivian hailstone

source

 

Written by LW

July 23, 2018 at 1:01 am

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