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Operation Popeye

en.wikipedia.org

1–10 of 21 posts

Re: Operation Popeye

#2
Interesting list of goals, how it was implemented, how it is now illegal...

But nowhere on the page does anyone say "it worked!" or "it was a boondoggle!", let alone share a statistical analysis that says "rain changed by X sigma over normal". That's a bit disappointing.

Re: Operation Popeye

#3

Interesting list of goals, how it was implemented, how it is now illegal... But nowhere on the page does anyone say "it worked!" or "it was a boondoggle!", let alone share a statistical analysis that says "rain changed by X sigma over normal". That's a bit disappointing.

Agreed, I'm surprised "did it work?" does not seem to be addressed.

According to:

https://www.globalsecurity.org/military/ops/popeye.htm

"In the end, however, it proved impossible to determine the amount of additional rainfall caused by cloud-seeding rather than other factors, and thus justify the recurring outlay. The Defense Intelligence Agency estimated that seeding increased rainfall "in limited areas up to 30 percent above that predicted for the existing conditions," but this figure admittedly was the result of "empirical and theoretical techniques based on units expended and the physical properties of the air mass seeded"-in short, a scientific guess. Sensor data showed only that the enemy consistently experienced difficulty keeping traffic moving through the monsoon rains, a normal problem for that time of year."

Re: Operation Popeye

#4

Interesting list of goals, how it was implemented, how it is now illegal... But nowhere on the page does anyone say "it worked!" or "it was a boondoggle!", let alone share a statistical analysis that says "rain changed by X sigma over normal". That's a bit disappointing.

Exactly what I was wondering. Did it work? I remember hearing that the science behind it has since been discredited.

Re: Operation Popeye

#6

Interesting list of goals, how it was implemented, how it is now illegal... But nowhere on the page does anyone say "it worked!" or "it was a boondoggle!", let alone share a statistical analysis that says "rain changed by X sigma over normal". That's a bit disappointing.

> But nowhere on the page does anyone say "it worked!"

Does it work? The Army definitely believed it could work at the time, but even today, nobody is sure. Many countries use cloud seeding in a routine basis for civil purposes, but there's still no scientific consensus [0] on the effectiveness of Cloud Seeding. Some researchers believes it works, others don't.

[0] https://en.wikipedia.org/wiki/Cloud_seeding#Effectiveness

Re: Operation Popeye

#7
Regarding the effectiveness:

https://99percentinvisible.org/episode/making-it-rain/

> Operation Popeye had four main objectives: to turn the roads to mud, to cause landslides along roadways, to wash out river crossings, and to keep roads muddier for longer than usual. But cloud seeding at the utime, and even today, is far from an exact science. At best , the military could measure three things: what the average rainfall for that area was, what the estimated rainfall would have been, and what actually fell after a seeding mission. But, in the end, they couldn’t collect enough data to rigorously analyze the outcomes. “The rain is completely variable,” says Fleming. “You have a tremendous temporal variability, spatial variability, and that means that statistics are not robust about what your particular intervention did to that particular rainfall.”

> And even if the U.S. military could make it rain, they couldn’t precisely control where the rain landed. One official described accidentally dumping a ton of rain on an American Special Forces camp.

> Nevertheless, Operation Popeye was deemed effective enough to continue for five years, from 1967 to 1972.

Re: Operation Popeye

#9

Interesting list of goals, how it was implemented, how it is now illegal... But nowhere on the page does anyone say "it worked!" or "it was a boondoggle!", let alone share a statistical analysis that says "rain changed by X sigma over normal". That's a bit disappointing.

US Senate Top Secret Committee hearing goes into this (p108). It mentions

(1) It is not possible to precisely quantify the effects due to lack of sufficient ground stations to report

(2) Defence Intelligence Agency estimates a 30% above the predictions for existing existing conditions in specified areas

[0] https://web.archive.org/web/20090612231729/http://www.sunshi...

Re: Operation Popeye

#10
It bothers me that one of the cloud seeding compounds they used was lead based. I wonder how much permanent pollution was left behind.
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