The SPF of Blue Plastic
Yes in spite of the weather warnings, thunderstorms and floods, we went to the beach. It barely sprinkled on the way. Because of my first-class tent and LM's vehicle, there was no fear of rain, and I was actually delighted with the possibility that cloud cover would give me some freedom to play on the beach.
He goes over to windsurf at Bird Island, I prefer to stay on the Gulf side. So that means I have to erect a shade structure in order to survive. Most folks either throw up a prefab or strap a blue tarp across their car and call it done. Time to pop a beer. But since LM needs the car to get to where he's going to windsurf, I have to create a freestanding structure, which is one of the fun, engineering tarpsmanship challenges of the beach. That is, if you can do it before you fry!
A lot of people don't even bother with creating shade. Reddish-brown Gulf Coast citizens fish, drink beer and smoke cigarettes all day long for days at a time in the full sun as if they never heard the word melanoma. I just can't do it anymore, as an ex-Gulf Coast citizen. I fled the beach as soon as I found trees and shade. I've had one suspicious mole removed, but the main thing is that the sun zaps my immune system. I'll get a herpes fever blister for sure or a simmering respiratory infection. Too much sun and too much petroleum-based pollution when I was growing up, I guess. There are brown pelicans now on the beach, lots of them. There were none when I was growing up, frollicking in their habitat, because DDT had done them in. They didn't start coming back till I had left for Austin. I love the pelicans, welcome back, guys.
So that brings me to the point of this essay: non-pre-fab shade engineering!
Last time we went to the beach, two years ago now, I created my shade out of a big blue plastic tarp. I used 3 tent poles to make parallel arches, set them into 5-gallon buckets full of sand and water, and lashed the tarp to said structure with a very long length of telephone cord. Rebar to stake it down pup-tent style, at either end. These are all excellent raw materials to take to the beach, and the sand-and-bucket system to hold it down from the wind worked for a day, and the sunburn I got was incurred while I was setting it up, which took about an hour. By the time LM got back, I had a "kitchen" and "lounge" inside it, and my special Beach Bloody Mary for coctails. He was very impressed, maybe one of the reasons he decided I was a kinda girl he'd like to hang out with.
But the wind blew it all flat and flappy overnight, and next day I sheltered in the car, watching LM windsurf.
One of the other non-prefab shade structures we oggled that time looked like it had been retrofitted from an old parachute! Very post-apocalyptic looking, Road Warrior sheik, and it used the wind to help hold it up. My blue tarp cave technology just attempted to let wind go through, but when the wind changed directions, it got smashed.
This time I erected the blue tarp tube again, and the wind was kinder. But I felt trapped and caged in, and by the end of that first day it was obvious that I was getting sunburned even through the blue plastic. Well, gee, I never thought to ask what the SPF of a blue tarp is!!! My estimate: about 70. Better than sunscreen, but sure not 100%. Oh, yeah, sunblock lotions give me rashes and zits, and do nothing to save my immune system, even if it protects from sunburn.
Day 2 We tried something that would not be so claustrophobic. It was inspired by that parachute thing we'd seen before. I took a sheet, which happened to be blue and pink tie-died, good beach colors, and tied knots at each of the four corners, which allowed me to firmly tie a cord to each corner, and gave it a bit of a concave shape. After a few permutations, we had the lead edge (into the wind) tied/supported by two flexible white pvc poles which were slipped onto rebar stakes driven into the sand to hold them in place, and the rear end tied to two buckets of sand and water. It puffed up like a sail, like a kite!, and since the open end looked out to the beach, into the prevailing wind, we had a great view. (Of sea, sand, pelicans, and...convoys of drilling machines.) Later on we added a cord-and bucket attached to one of the front corners, which allowed us to yank it whichever direction, within about 30 degrees, the changing condition of the winds indicated. the back ends were 100% adjustable. You just hadd to move buckets and tie line to different lengths to get the best lift and shade coverage possible. Bet you'd like to see a picture, I'll see if I can figure out how to do that.
What's the SPF of a tie-dyed sheet?? I think about the same as a blue tarp. If I do this again, and I would go straight for the same technology, I'd use a dark-colored sheet to block more UVs. Unless I can find me a used parachute...
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