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Eliminating contrails from flying could be cheap

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Re: Eliminating contrails from flying could be cheap

#121

Post by sjf »

extraduder_ire wrote: post #90
Agree2468 wrote: post #72

Earlier quoted context omitted.

If you're ever in DC, you should check out the ads in the metro stops near the Pentagon. Seeing those kinds of ads in real life is even more shocking.

I saw some photos of those ads on twitter a few years back about a certain manufacturer's engine being the correct choice for a specific in-development military plane. It's weird seeing physical advertising be so targeted. Like, multiple physical ads to target less than a dozen people total.

[The I-80 east has entered the chat]

Re: Eliminating contrails from flying could be cheap

#122

Post by greekrich92 »

dustfinger wrote: post #116

There are a lot of comments here mocking “chemtrail” believers, but I think the confusion is understandable. There seems to be a mix-up between three terms: contrails, chemtrails, and cloud seeding. Contrails are just condensation trails caused by jet exhaust and air pressure differences at high altitude. Cloud seeding, on the other hand, is a real weather-modification technique that uses aircraft to disperse substan…

The chemtrails conspiracy nuts aren't confused about cloud seeding. They believe contrails are visible evidence that airplanes are used to disperse mind control drugs over the populations below.

Re: Eliminating contrails from flying could be cheap

#123

Post by Retric »

varenc wrote: post #107
Retric wrote: post #76

Earlier quoted context omitted.

Walked into a weapons show a few decades ago that had a full scale Abrams tank + demo camera providing good 360 degree visibility. It was odd because I was like yea this is obviously a good idea, but also I’m not the person you need to convince here so WTF.

How'd you find a weapons show? Which one? are these semi-open to the public? Sounds fascinating

I was walking around Arlington VA area and saw some signs of fighter jets and such that looked interesting, no idea of the show beyond that really.

I did have a pentagon badge at the time which let me in, not sure if it was necessary though.

Re: Eliminating contrails from flying could be cheap

#124

Post by datadrivenangel »

sjf wrote: post #121
extraduder_ire wrote: post #90

Earlier quoted context omitted.

I saw some photos of those ads on twitter a few years back about a certain manufacturer's engine being the correct choice for a specific in-development military plane. It's weird seeing physical advertising be so targeted. Like, multiple physical ads to target less than a dozen people total.

[The I-80 east has entered the chat]

The tech billboards in SF are also wild.

Re: Eliminating contrails from flying could be cheap

#125

Post by fragmede »

ThinkBeat wrote: post #92

Somehow telling airlines to fly what might be quite a bit longer, in order to avoid all the different contrail potenial spot, that will use even more fuel migth nto be a popoular sell?

from up thread, Google told American airlines exactly that https://sites.research.google/gr/contrails/

Re: Eliminating contrails from flying could be cheap

#126

Post by redtexture »

Havoc wrote: post #96
aeternum wrote: post #94

Earlier quoted context omitted.

This seems pretty useless in an age with super cheap 8k cameras and novice ability to do a delta-recorded image.

What do you mean by delta-recorded image?

Delta encoding.

https://en.wikipedia.org/wiki/Delta_encoding

Re: Eliminating contrails from flying could be cheap

#127

Post by add-sub-mul-div »

solid_fuel wrote: post #117
tbrownaw wrote: post #95

Earlier quoted context omitted.

> 5G RF is invisible, yet still being used by the government to control our brains. Well it's one of the main last-mile mediums people use to doomscroll their propaganda feeds, so... yes?

It's funny how often the conspiracy types are both right and wrong. We have precision targeted ~~propaganda~~ content streaming straight to the tracking device everyone willingly carries, but they land on 5G being some sci-fi form of mind control. It's some form of motivated reasoning. The same people who will tell you a secret cabal of billionaires controls the government will roll their eyes if you bring up the her…

They can't abide pretend child endangerment happening in pizza basements, but point out the Catholic church or Trump perving on Miss Teen USA contestants in their dressing room and they don't seem to care.

Re: Eliminating contrails from flying could be cheap

#128

Post by cindyllm »

add-sub-mul-div wrote: post #127
solid_fuel wrote: post #117

Earlier quoted context omitted.

It's funny how often the conspiracy types are both right and wrong. We have precision targeted ~~propaganda~~ content streaming straight to the tracking device everyone willingly carries, but they land on 5G being some sci-fi form of mind control. It's some form of motivated reasoning. The same people who will tell you a secret cabal of billionaires controls the government will roll their eyes if you bring up the her…

They can't abide pretend child endangerment happening in pizza basements, but point out the Catholic church or Trump perving on Miss Teen USA contestants in their dressing room and they don't seem to care.

[dead]

Re: Eliminating contrails from flying could be cheap

#129

Post by crazygringo »

I'm so confused. This article is explaining that eliminating contrails would have a significant effect on warming.

But contrails are just the tiniest, tiniest fraction of the sky somewhere and only last over a given area for a few minutes generally. Like, sure, if you live next to a busy airport maybe you see them more often, but that's balanced out by the 99.9% of sky not next to a busy airport. Plus the many days that they just don't show up at all, because they depend on certain weather conditions.

I mean, this just doesn't pass the smell test.

But Wikipedia has an entire section [1] full of citations. But then... it sounds like maybe a lot of them aren't credible or suggest that it's not a problem? E.g.:

> However, follow-up studies found that a natural change in cloud cover can more than explain these findings. The authors of a 2008 study wrote, "The variations in high cloud cover, including contrails and contrail-induced cirrus clouds, contribute weakly to the changes in the diurnal temperature range, which is governed primarily by lower altitude clouds, winds, and humidity."

> Then, the global response to the 2020 coronavirus pandemic led to a reduction in global air traffic of nearly 70% relative to 2019. Thus, it provided an extended opportunity to study the impact of contrails on regional and global temperature. Multiple studies found "no significant response of diurnal surface air temperature range" as the result of contrail changes, and either "no net significant global ERF" (effective radiative forcing) or a very small warming effect.

So it sounds like this theoretical contrail warming problem possibly doesn't exist? I find it strange the article doesn't even acknowledge any discussion over whether it's actually a problem in the first place.

[1] https://en.wikipedia.org/wiki/Contrail#Impacts_on_climate

Re: Eliminating contrails from flying could be cheap

#130

Post by aeternum »

nine_k wrote: post #106
aeternum wrote: post #94

Earlier quoted context omitted.

This seems pretty useless in an age with super cheap 8k cameras and novice ability to do a delta-recorded image.

Numbers don't add up. If you take a 8K camera with a standard 50 mm lens, its angular resolution is about 20" / pixel. A 50 mm lens has a FOV of about 40°. It covers a cone of about 0.38 strad. A full hemisphere has 2·pi = 6.28 strad, so we need at least 16.5 such cones to cover the whole area; actually we need likely 20-25 because of imperfect geometry and some safety margins at intersections. We can, of course, mou…

Most camera sensors already detect in the IR range, you just need to remove the filter. I've done it, works great and pretty fun to convert some old webcams, robot vacuums lidar scanners look especially cool.

Blurry video is fine when using techniques like this: https://www.youtube.com/watch?v=m-b51C82-UE

Clouds also don't save you (unless you have two thick layers to fly through) because this technique is even easier with satellites. Stealth effectively no longer exists for most nation-state level tech. The B-2 is a very cool plane but is unfortunately obsolete. Still great for when you want to put on more of a show than an attack.

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