Solstice

Can you say “happy solstice”? Darkness, short days, cold, and all. At least up north, which is where I’ve experienced every single solstice in my lifetime. In any case, it’s here, this very minute. Come back, sun!

Space Visitors, Again

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As I just wrote to my brother John;

“… I wasn’t so lucky with the pictures last night. It

started clouding up about an hour before sunset, and

the space station and ISS were crossing well to the

north (maximum elevation was about 27 degrees). So it

was doubtful they’d be as bright even if they were

visible. At the scheduled time — the shuttle was

supposed to appear at 6:03, the ISS at 6:04 — I

couldn’t see anything, but I released the shutter

anyway. After about 30 seconds, I could see something

moving dimly above the clouds in the northwest. After

the first 60-second shot, I reaimed the camera further

east, and realized there were two objects moving by; I

had missed the first, the shuttle, but both were

clearly visible as they crossed through the north to

the northeast. I tried another 60-second shot and got

both of them, though they don’t look nearly as bright

as they did just looking at them. Looking at the shots

now, there was so much ambient light that the sky

became very washed out, and a shorter exposure might

have shown them better Something to remember for next

time.

“Still — pretty amazing stuff. I was seeing them about

four hours after they had separated; if you assume

they were exactly a minute apart, that means the

distance between them was just under 300 miles (the

distance they travel in 60 seconds at 17,500 mph).

Looks like it will be too cloudy here to see the

shuttle again before it lands.”

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Today’s Frost Report

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Down to freezing again overnight (yes, I’m conscious that most of the vegetation on which the frost forms here is green, not Northern Hemisphere winter brown). Those little crystals of ice? They’re called spicules (according to the OED, which refers to them as spicula, a spicule is “1. A sharp-pointed or acicular crystal or similar formation … b. esp. A formation of this nature caused by the action of frost”).

Jack Frost Nipping at Your Ankles

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Frost this morning, leading to today’s inquiry: How does frost form if the air temperature is above freezing? Frost is ice, after all, so where does it come from if your reasonably accurate thermometer (ours: on the back porch, six feet above the ground) shows that it’s 38 degrees outside? What accounts for car roofs getting frosted when there’s no other sign of frost in the area?

I never thought about this much growing up in Illinois because when you saw frost, it was usually well below freezing. Here, I started to wonder about it because wintertime frost is common in our relatively mild bayside climes, mostly when the thermometer is showing a temperature five or six degrees or more above freezing.

The short answer (from a couple of just-OK references, here and here) is that frost only forms (it sublimates, from water vapor directly to ice) in the presence of freezing temperatures. The temperature that’s critical in the process is not the air temperature several feet off the ground, where most thermometers are placed, but at the surface where frost is formed. Among the factors that make ground temperatures significantly colder than the air several feet above are radiative cooling–the process by which the ground is surrendering heat energy into the atmosphere in the absence of some input (sunlight, for instance)–and the tendency of cold air to sink. So while it’s 38 degrees at an altitude of six feet, it can be 32 or below on the ground; if there’s sufficient moisture in the air, frost will form.

And the presence of frost on car roofs, etc., when there’s little or no frost nearby? The same general explanation holds; the difference is that exposed metal and glass radiate heat faster and more completely than ground surfaces and thus reach the frost point more quickly. A car roof is an example of a sort of micro-micro-climate, I guess.

[Update, 12/19: I found a second thermometer and measured the temperature at the ground to compare it to the temperature recorded on our indoor-outdoor thermometer, which has a sensor at a height of six feet above the ground. The latter recorded a low this morning of 35 degrees; at the same time, the ground thermometer, which was just half an inch above the ground on one of those Frisbee donut things (so that air could circulate under it and so that it would not be resting directly on the ground), showed a temperature of 27 degrees.]

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Holiday Audio

Tiny Tim's Christmas Album

(Set in motion by the Beancounter):

The problem with declaring an all-time music list, let alone a Christmas-themed one, is that I just don’t know that much music. Not compared to anyone else I know, certainly. But not knowing a lot about something doesn’t stop me from proceeding on my self-appointed rounds. Here goes (and if you’ve got suggestions, add ’em). In no particular order, and without explanation except where I’ve been overcome by the usual urge.

“Merry Christmas Baby,” Otis Redding (on “The Original Soul Christmas”).

“What Are You Doing New Year’s Eve?” King Curtis (on “The Original Soul Christmas”).

“The Wexford Carol,” Nanci Griffith (on the Chieftains’ “The Bells of Dublin”).

“Christmas Must Be Tonight,” The Band (on “Islands”).

“Christmas in Prison,” John Prine (on “A John Prine Christmas”).

“Oh, What a Beautiful City,” Pete Seeger (on “Traditional Christmas Carols”).

“Cherry Tree Carol,” Joan Baez (on “Joan Baez, Vol. 2”).

“Children Go Where I Send Thee,” Loose Ties (a cut, ,and band, I came across on the Tom Rush website).

“Calling All Angels,” The Wailin’ Jennies (good luck finding this one; they played it on “Prairie Home Companion” earlier this year; worth looking up the show and listening just for that song).

“(What’s So Funny ‘Bout) Peace, Love & Understanding,” Nick Lowe.

I’m sure I’ll think of more. …

[Yes, and here they are:

“Snow,” Jesse Winchester (on “Jesse Winchester”).

“The Rebel Jesus,” Jackson Browne (on “The Bells of Dublin”).

“Three Angels,” Bob Dylan (on “New Morning).

[List in progress. … And the image: Thanks, Lydell! It sets just the right tinny, nasal, annoying tone.]

About a Map

Following up on an earlier post on what may be an incidental contradiction in the earlier accounts of the Kim family’s travels in Oregon on November 25:

Some news outlets, including James Kim’s employer, CNET, reported the family stopped at the Wilsonville, Oregon, Chamber of Commerce on their way south to get a map and travel directions to Gold Beach, their planned destination. The CNET story said that someone working at the chamber had warned the Kims against using the road on which they attempted to cross the Coast Range. Later, Lt. Gregg Hastings of the Oregon State Police said the Wilsonville visit never occurred. Relating an account from Kati Kim, Hastings said the family had missed their planned route, state Highway 42 (off of Interstate 5, just five or six miles south of where the Kims ate dinner, a Denny’s in Roseburg). After discovering their mistake, they consulted a map and continued south to try Bear Camp Road (the nearest I-5 exit that would have led to that route was about 60 miles south of their dinner stop).

What actually happened in Wilsonville, if anything? Earlier, I called the Wilsonville chamber, whose executive director insists that one of his tourist-info volunteers had spoken to the Kims and cautioned them against Bear Camp Road and other routes off the main highways. This morning, I finally got hold of Lt. Hastings to ask why the state police had discounted that report.

“My statement was based upon the fact I was told by our detective who interviewed Kati (Kim) that, according to the detective, they did not stop there,” Hastings said.” And we thought it was important because the Chamber of Commerce was getting several calls about this, that we should make that statement and clear that up.” Hastings added that the state police detective had interviewed Kati Kim in her hospital room (she and her two daughters were taken to Three Rivers Hospital in Grants Pass on Dec. 4 and released Dec. 5).

Mark Ottenad, the Wilsonville chamber’s executive director, suggested the Kims might not have realized they had stopped at the chamber office because signs on the facility referred to the Clackamas County Regional Visitor Information Center. Asked about that possibility, Hastings said, “I have no idea. My understanding is that they did not stop in Wilsonville.”

The Wilsonville chamber people said they had given the Kims a copy of the official state road map. I asked Hastings whether he had any certain knowledge about what map the Kims used when they chose their alternate route. “it’s the one the state of Oregon makes available to people,” Hastings said. “I’ve got three here, and in fact i’m looking at one now.” He added that he didn’t know where the Kims got their copy of the map.

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