Category Archives: Clouds

Saturday sunset

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It was sunset Saturday evening after a pizza and a quick trip to the mall. Of course all I had with me was my phone, despite my promise to myself to aways take at least our little point-and-shoot camera. This was the best I could do.

sunset19mar16

This is a panorama made in Photoshop Elements rather than by the phone itself. The pano-mode on the iPhone is convenient and works pretty well, but this was a stressing scene. All the color was in the brightest part of the sky, but the phone wanted to expose for the largest area, which left the bright part of the sky overexposed. I resorted to taking two separate images, forcing the phone’s camera to expose more accurately for the bright sky, but even so, it doesn’t really capture the sky as we saw it. I think I might have been able to do better, but the light was going fast. The actual scene when I took the picture was about five minutes too late to capture the really dramatic sky we saw when we first walked out of the mall. I couldn’t take the picture then without getting parking lot lights and other stuff I didn’t want, so we got into the car and drove to a better vantage point. That gave us a better view of the sky, but it was already too late.

Sky with contrails

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contrails

We have lots of commercial jets flying over us, most probably coming to or from Atlanta. Five of them left their contrails for us to see Sunday morning.

Contrails (condensation trails) are caused by water vapor condensing on tiny particulates in the exhaust of aircraft engines. Today we tend to think that means jet engines, but all engines produce at last some particulates. You may have seen photographs of World War II bombers flying at high altitude leaving contrails. Here’s an example taken by the Army Air Corps during WW II.

wwiicontrails

The water vapor that causes contrails can come from the water vapor produced by the engine (burning petroleum fuel produces mainly carbon dioxide and water vapor) or water vapor in the surrounding air. The water vapor may not condense into visible droplets if there are no condensation nuclei. Particulates produced in the engine combustion provide the condensation nuclei that are needed. If the air at the altitude where the aircraft is flying is not very humid, a contrail can dissipate quickly. If it is humid, the contrail can stick around for a long time, or even continue to grow and form much larger clouds.

Our skies must have been fairly humid Sunday morning because these contrails remained visible for some time.

If contrails remain visible for long enough, you may be able to see how the wind at altitude can blow in different directions at different locations by the way the line of the contrail distorts. You could also estimate the wind velocity if you were so inclined.

Bob Roper, a professor at Georgia Tech who was on my reading committee, studied what were called meteor winds. He had a radar unit that looked up at very high altitudes, near the top of the atmosphere. Meteors that routinely crash into the upper atmosphere create ionization trails that reflect radar. By measuring the apparent motion of the ionization trails as seen by the radar, the wind velocity can be estimated. If you’re really interested in meteor wind measurements, you can get one of his articles here for $31.50. Or you could probably visit your local university library and ask for help finding atmospheric science journals. I imagine that neither course will be particularly attractive, and I’m afraid the article would be pretty dry anyway.

As one of the very few scientists doing meteor wind measurements in the West, Dr. Roper sometimes got to visit the USSR, where they also did such work. Back in those days, he would be debriefed by the US authorities when he returned. One time the Russians showed him a radar that could look over the horizon and detect, let’s just say for the sake of argument, ships in the Persian Gulf. He thought that was rather odd, since he was really interested only in radars that looked pretty much straight up. He figured that the Russians would expect him to be debriefed when he returned, and that the Russians probably wanted the US to know the USSR could watch US ships from afar.

Pink clouds peeking

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We saw some nice clouds on the way home from the Mexican restaurant on Sunday night. We had just finished eating our traditional Wednesday lunch of huevos rancheros, rescheduled for Sunday evening because of Leah’s slow recovery from her surgery. Most of the western sky was covered with dark clouds, but there were some pink clouds peeking through gaps here and there.

pink peeking clouds

As usual, this was taken with my iPhone. It does not capture the contrast in brightness and color, but it was the best I could do. I keep saying I’m going to take an actual camera along with me everywhere I go, but I keep not doing it. With a camera I could have zoomed in on the pink areas, but even then it would not have shown enough of the darker clouds to see the real contrast. I imagine a better photographer or a better Photoshopper could get this shot.

Leah did OK with the huevos rancheros, but she didn’t really eat much. She said her eyes were bigger than her stomach, which is probably pretty small these days given how little solid food she is eating. The incision and the interior of her abdomen are still hurting. That combined with arthritic pain in her neck forces her to lie down occasionally through the day to try to calm the pain. It’s slow, but she’s making it.

Post-Christmas roundup

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Christmas day was quiet up on the mountain. I’m not sure we have done less on any given day in the recent past. We mostly sat around and listened to the rain. The only time I went outside was a quick trip up the road to let Zeke take care of his business, and a couple of even quicker trips around the house to let both dogs do their business. The rest of the time we stayed inside, and did nothing and saw no one.

We had been having egg nog every evening since Thanksgiving, so Thursday night when we realized we had run out of egg nog before we ran out of Southern Comfort, I went back down to the grocery store for more. They were sold out. I checked a couple of liquor stores, and they had run out, too. I stopped at a convenience store and they didn’t know what egg nog was. So we didn’t have egg nog for Christmas night.

We had another foiled Christmas tradition. Leah has made it a custom to give the guy who makes our eyeglasses a spiked fruitcake every Christmas. We prepared the fruitcake and took it by his office on Tuesday, only to find out that they had closed their office until the Monday after Christmas. I think it will be okay to deliver on Monday; I’m pretty sure it has been properly preserved.

Late in the day Leah started preparing Christmas dinner. We had deep-fried turkey (store bought) and cornbread dressing (home made, and very good) with turkey gravy (let’s say half store bought and half home made). It was good, so I ate a lot. Leah says she ate a lot, but she really didn’t.

A few days before Christmas we had given in and put a couple of decorations in the living room, but we didn’t put up a tree. That was OK, since we had each bought our own presents weeks earlier.

All in all, we both thought it was a pretty decent Christmas. We hope everyone had at least as good Christmas as we did.

The most memorable features of Christmas here, as well as most of the East Coast, were rain and extraordinarily high temperatures. A lot of places west and south of us had much more rain and much worse weather than we did, but we had a lot of rain. When I went outside Saturday morning, I could hear the dull road from the rush of water in all the streams flowing down the mountain. The rivers and most of the larger streams around Rome were at or over flood stage, although there was no severe flooding. We don’t know exactly how much rain we had on the mountain, because our rain gauge is broken.

Saturday morning we saw sunlight for the first time in days.

morning26dec15

A little later it looked like the clouds would disappear.

morning2_26dec15

And then a little later than that, it looked like it would rain again.

morning3_26dec15

It did rain, but only a light mist that didn’t even get me and the dogs wet when we went up to look at the house. The house weather tight now, but someone left a window open before it started raining, so the floor sheathing was wet in some places. I wanted to see if a particular place was wetter. It wasn’t, but it also wasn’t dry. I don’t know whether it’s a leak, or maybe someone just dropped a water bottle.

We had a rough inspection on December 23. It covered plumbing, electrical, heating and air conditioning, and framing. The inspector left me with a list of eight things that need to be addressed before he will sign off. Two are fairly serious framing issues. The ridge beam needs more support for one thing. That should be straightforward. The other issue is a butchered i-joist where the plumber cut away some of the upper part of the joist to get the master bath shower drain in. When I saw that a few days earlier I knew it was going to be a problem; I just don’t know why the plumbers didn’t know that. I have to call the framer to see what we can do about those two issues.

The plumber also missed a few places that need metal plates to protect pipes from drywall screws and nails. I also don’t know why they missed those, but at least all those will require is a metal plate and a few nails.

The inspector found no problems with the electrical or heating/cooling system. That’s good. He also said we can proceed with insulation, since that won’t cover any of the required fixes.

So insulation is the next big project, and I intend to do this one myself.

Some sky shots

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I bought a tub enclosure for the new house Thursday afternoon (Nov 12). This is what I saw as I was leaving.

sundog2

There is a nice sundog on the right. There were no clouds to the left of the sun, so no sundog there. There is a hint of color above the sun which may be a camera artifact, although it seems to appear in cloud areas and (perhaps) not in clear sky. If the clouds had had the right mix of ice crystals, the sundog could have extended up into the clouds above it. The clouds obviously contained mostly hexagonal flat plates, which tend to orient themselves horizontally so that the sunlight passes through them along the hexagonal edges, dispersing the colored light only in limited directions. The “right” crystals would have included a significant percentage of hexagonal columns, which have no preferred orientation and can thus disperse the light into more directions. Anyway, it was nice.

On Sunday morning Leah told me to go onto the deck and see the sunrise.

sunrise16nov2015

I shot this with our little Nikon point-and-shoot. I wonder if the iPhone would have done a better job with exposure, since it seems to have a wider dynamic range. The bright areas might not have washed out.