No, it's better than installing artificial snow to reflect energy.
The snow doesn't change the energy budget of the earth at night, because there is nothing for it to reflect, and the infrared energy it emits is pretty much like the infrared energy from most other surfaces, and a certain percentage makes it off planet and the atmosphere absorbs a certain percentage.
The skypaint emits infrared in a particular bandwidth which the atmosphere does not absorb, called the "atmospheric window", so a much higher portion of it's energy makes it off the planet. This effect will operate regardless of whether the sun is shining on it or not, it will keep dumping something around 120 watts per square meter off the planet as long as it is exposed to the sky.
“Other than all the environmental damage, why not?” all the time. They weigh the likelihood of being caught or not, and do a cost/benefit analysis. They choose environmental damage just for a 1% increase in profit margins.
If they can do it, why can’t a properly funded radical geoengineering activist group do it?
Because they rule society and activist groups don't? Not sure what you're getting at. Obviously the rules in society aren't applicable to the ruling class, that doesn't change the fact that an activist group would be stopped by intelligence services before doing anything like this. Pointing out hypocrisy unfortunately has no power to stop it.
I followed NightHawkInLight's recipe from youtube, and I've made several batches so far.
I tested the results with an insulated box with an open top covered with glad wrap, and confirmed 11 F less than ambient temp at night, at a variety of humidities. I haven't gotten up early ( or stayed up late ) enough to do a test in the early morning when it's close to 100 percent humidity, but it seems to not be affected by atmospheric humidity, which would confirm it's emitting at that "atmospheric window".
The materials are cheap at scale and the process is probably about as complicated as brewing beer, actually probably less so.
I bought a pack of standard asphalt roofing tiles, so I could paint them and leave them exposed and see how quickly dust, rain and etc degraded the effect. I used the acrylic / acetone / water paint that NightHawkInLight describes, but also tried mixing it with clear coat, and I have a few other cheap and scalable application methods to try.
How did you measure the temperature of the painted material?
The saw on this previously (just one yourube video) measured the temperature by using a an infrared temperature device. Which is not the same as the actual surface temperature. The temperature is inferred from the amount of infrared light detected, and the assumed emissivity of the surface.
So when the the author concluded that the paint lowered the temperature of the surface by only measuring it with an infrared thermometer, it seemed a flawed conclusion to me.
He had only shown that less infrared was emitted than other nearby surfaces, not that the temperature was lower.
I'd like to second your recommendation of Deep C Secrets. I originally bought it purely for the title pun, but it is actually one of the better programming books I own ( and I have a lot ).
Jason has a similar ( maybe the same ? ) Defcon talk, in which the goons apparently mis-schedule something and he starts in, is told someone else is going to present, and just power-speeds through the whole presentation in 3 minutes while the other presenter gets ready. I can't find that video though.
Not sure if this is a great project if you are recovering and don't have some type of CNC mill to test it on -- but the state of open source "CAM" software is clunky.
"CAM" is computer aided machineing and it is software that takes a 3D model and a lot of machine parameters in, including size of the cutting bit and etc, and produces "g code" which is movement instructions for a computer controlled mill of some type.
It is the equivalent of the "slicer" in 3D printing.
But for milling or subtractive manufacturing there are many more details, and there needs to be a way to visualize and simulate the toolpath, and edit it by hand.
I attended a talk at Defcon in 2007 or 2006 which was given by Chris Tarnovsky, in which he alluded to some of details covered in this article. It was definitely one of my formative tech career experiences, I don't remember much of the other talks then, but I think I could almost recount his presentation word for word, and I stayed after for an informal demo after the talk was "over". Mingling in that crowd I ran into a person who I vaguely remembered from college, who I would never have thought to show up in that environment.
I think it was that experience, along with a later experience at "Do it with Drupal" in New Orleans, that lead to me completely re-evaluating how I valued and approached conferences and other "community" type events. Prior to that I put them in the same class as picking the right powerpoint template and buying obnoxious people drinks at the hotel bar, i.e., complete sales / business fluff to my nerdy point of view. After Defcon and that presentation in particular, I tried to never miss any of the "community run" tech events, such as Defcon, Linux Fests, Drupal camps, etc.
Thanks for linking to that . . . it was fascinating to search through it for some of the small rural places I've lived or had connections to and see familiar names pop up, and think "of course he would have run FidoNet node".
Was not too surprised to see Joe Barr (Austin) in there. He died in 2008 and Linux Journal, where a lot of his writing was published, is gone now also.
The co-op model is basically my last sentence and the fees/restrictions are a lot higher than most people want from a maker space. It can definitely work, though. Also it's important to distinguish between maker space and hacker space. The latter can be profitable since you're often making your money renting out communal working space ala the WeWork model. The former is a lot harder to pull off.
