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The Boggling Superpower of Bubble Wrap

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We’re long past the End of Owgust. The End of September is upon us, and my pool is still at 93° F. Why? It has nothing to do with global warming, and everything to do with a 20′ by 40′ sheet of blue bubble wrap. Back toward the end of spring, Carol and I bought a swimming pool cover. It came in a box, and it was just what I described: a 20′ X 40′ sheet of bubble wrap. I had to modify the corners a little to make it fit my idiosyncratically shaped in-ground pool, but that took less than an hour with a pair of ordinary scissors.

Now, in a riproaring Phoenix summer, you don’t need no steenking pool cover to keep your pool upwards of 90°. Just sitting there in the sun all day, my 44,000 gallon diving pool hit 95 degrees in early July all by its lonesome. But as we got into September and the days got shorter, the water temp soon fell to 85°. This feels great when the air temp is 110, but the air temp fell with the length of the day, and especially in our late-evening dips before bed, the air temp was in the high 80s and the water actually felt better warm. So two weeks ago, with the water temp at 85°, we dragged out the pool cover and wrestled it into place on the water.

Then, day by day, we boggled as the water temperature rose. By this afternoon, with a daily high a mere 100° (lukewarm by Phoenix standards) the water was at 93°. Carol’s sister Kathy is coming down for a visit in ten days, and she’s expecting warm days and warm pool water. The days will be in the 90s, which, if your’re accustomed to Chicago weather, is plenty warm. The challenge is to keep the water above 90° into the middle of October. I was a little worried about that.

Not anymore.

It’s been an interesting science experiment. At the end of a sunny day, the water immediately under the pool cover comes very close to 100°. That’s just for the top 2″ or so. When the pool pump kicks in at 8PM, it mixes that hot top layer with the cooler water beneath it. Come morning, the water is all mixed, and has gained half a degree or more throughout. The pool cover prevents most of the radiation by which pools lose their warmth at the end of summer. With the Sun to add new heat every day, and the cover to prevent it from radiating into the night sky, the pool accumulates heat. I think that 93° is the equilibrium temperature when the daily highs hover around 100°. We’re heading into a cooler week, so I don’t know precisley how that’s going to go, but as long as I can maintain 90° I’ll be more than happy.

The cover cost about $200. This may seem high for a sheet of bubble wrap, but in truth, it’s not the same kind of bubble wrap you get at the UPS Store to stuff in around the knicknacks you’re shipping to your godmother. The plastic is heavier and more rugged, and with some luck and careful handling could last 3-4 years.

Kathy’s visit will be a good test, but the primary experiment is to find out how long the cover can extend pool season, which by our definition is when the pool is at 82°or higher. We’re expecting to make it to Halloween, and–given reasonably warm weather and all sunny days–hoping to make it to Thanksgiving. There will be another experiment next March or April, to see when the cover brings the pool temp up to 82° for the first time in the season.

Sometime this winter, we’re going to have the pool “depth-modified,” which means that they’re going to jackhammer out the plaster, fill in the 9′ deep end, and replaster it to become a “play pool,” which will be 5′ in the center, and 3-4′ deep at both ends. I was never much of a diver, and I think we may score a discount on our homowner’s policy for getting rid of that 9′ depth. With only 30,000 gallons or so in the modified pool, who knows? We could be in the water 9 months out of the year. Maybe more.

Solar power rocks. It isn’t all photovoltaics.

Odd Lots

Odd Lots

  • There’s a useful overview of the latest Ubuntu release (9.10) here. Note the cautions about the 9.10 partitioner, especially if you have more than one SATA drive in a system destined for a clean install on a shared drive. I ran into some still-unresolved difficulties with the partitioner recently, but they seem to be machine-specific and may be due to BIOS limitations. More on that as I learn it.
  • A similar site for Kubuntu 9.10 is here.
  • I’m not much into costuming (or Halloween, for that matter; my sister got that gene instead) but within the genre of one-person-pretending-to-be-two, this may well be best-of-breed.
  • On the other hand, this one comes close, for sheer attention to detail if nothing else.
  • And while we’re talking tauntauns, didja see the tauntaun sleeping bag? Authentic right down to the tauntaun guts pattern on the lining. (Thanks to Pete Albrecht for the link.)
  • 2009 is now #8 on the most-sunspotless-years-since-1849 hit parade. Ten more spotless days and we move into position #7. I’m laying odds that 2009 will eventually get into 6th place but no higher.
  • God may not like the Higgs Boson, but hey, I’m not all that fond of opera. (Thanks to Pete Albrecht for the link.)
  • Here’s an interesting pamphlet from 1945 on what the future of television might be. If they only knew…
  • Frank Glover sent a link to an article sponsored by the ESA suggesting some SF ideas that have been realized to some extent or still may have some promise in our own (and not some alternative) future. A little breezy, but has a lot of full-color SF art and classic magazine covers. (5 MB PDF.)
  • This may seem like a weird stunt, but it was (and may still be) a common thing on dairy farms. When I was 10 or 11, I watched Auntie Della milk a cow by hand one morning for the day’s needs, and the barn cats (who kept the barn free of mice) would line up for their milk squirts. Auntie Della’s aim was very good, and by all indications the cats were completely good with that.
  • Make Magazine published a brilliant little project: A vacuum cleaner hose trap for small parts like screws and washers. (110K PDF.) Doesn’t rely on magnetism, but is more like a lobster trap, in that parts enter easily but can’t leave, and rattle around tellingly when the hose pulls them in.
  • From the Jolly Pirate comes word of the Corsair Flash Voyager GT: A 128 GB thumb drive optimized for speed, and (according to him) capable of holding over 20,000 MP3s. $400 now…but check again in six months, heh.
  • Turn the Dodge Viper logo upside-down, and what you’ve got is Daffy Duck.

Odd Lots

  • Yes, I’ve been lax on posting, but we’ve taken a short vacation with Carol’s family, and I’m reading PDFs of the finished pages in my book, for reasons that I don’t need to go into here. I have lots to post about, but little time or energy to do it. Bear with me.
  • Our new puppy now weighs five pounds and is going on eleven weeks old. He still hasn’t told us his true name, but we’ve suggested Dash, Pascal, Dover (think “White Cliffs of”) and two dozen other things, and all he wants to do is chew on Carol’s slippers. At least he’s learned to use the potty pad, a trick Aero never quite mastered.
  • You can help classify galaxies from the Sloan Digital Sky Survey over at the Galaxy Zoo, which is one of the coolest crowdsourcing apps I’ve ever seen. You don’t have to know anything about astronomy to classify galaxies, but people who are passionate about galaxies may find the process less boring.
  • Anyone who has ever killed time with Conway’s Game of Life has got to see this video, of a spaceship gun: a large, complex GoL pattern that generates moving “spaceship” automata that then crawl away toward the right. The gun seen from a height looks stable and in its own way beautiful, but at higher magnification it’s full of furious activity, almost like a chaotic Pac Man game. How such things are designed escapes me completely, but this makes me wonder what larger and even more complex GoL structures exist and have not yet been designed. (Discovered?) Thanks to David Stafford for the link.
  • David’s hot this week: He also sent a link to an extremely intriguing article suggesting a different sort of cosmic cycle: After the Big Bang, time began running, but then gradually slows down until it stops. At that point, what had been the time dimension becomes a new space dimension, and (presumably) the whole thing blows up again with a brand-new time dimension, as a richer and in some respects more mature cosmos. Shades of Stapledon’s Star Maker.
  • Although we’re still seeing TV spots by the late, great (ok, loud) Billy Mays, Mays has an heir-apparent: Vince Offer, who has begun to saturate off-peak Weather Channel ad space with pitches for Sham Wow and the resurrected Blitzhacker, now unfortunately called Slap Chop in the US. (Carol and I had one thirty years ago, and it was indeed useful.) Mays had a certain goofy warmth about him. Vince, well, he’s just…scary.
  • “Sheesh, this thing is ancient! If it breaks, where am I going to find another?”