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  • The Comprehensive Nuclear-Test-Band Treaty prohibits all nuclear explosions anywhere on Earth

  • for any purpose, period.

  • Though as of 2015, it still remains to be signed and/or locally ratified in a few important places.

  • In spite of this, the Test-Band preparatory commission has already developed a monitoring system

  • that can detect pretty much any nuclear explosion that takes place anywhere on, above, or inside the Earth.

  • Here's how it works

  • Nuclear explosions release a lot of energy

  • much of it in the form of blast waves that radiate outwards through the air, water, or ground.

  • These waves travel at the speed of sound in the air, water, or rock

  • so if you detect them in multiple places you can triangulate exactly where and when the blast occurred.

  • Simple in principle, complicated in practice.

  • Atmospheric explosions are monitored by a global network of infra-sound detectors.

  • They detect the super-long wavelength, low frequency sound waves generated by

  • storms, glaciers, volcanic eruptions, meteor impacts, rocket launches, space shuttle disasters

  • and yes, nuclear explosions.

  • However, nuclear explosions are so much more intense than pretty much anything else

  • that happens in the atmosphere, that an atmospheric blast is pretty easy to detect.

  • Underwater detonations are monitored by hydro-acoustic sensors.

  • Basically, super sensitive underwater microphones floating above the ocean floor.

  • And like in the atmosphere, underwater nuclear blasts are pretty easy to detect

  • because there's just nothing else that violent that happens in the oceans.

  • Underground explosions are the tough ones.

  • They're monitored using seismometers, the same tools that detect earthquakes

  • and as you might expect, they mainly detect earthquakes.

  • Big earthquakes, small earthquakes, and lots of tiny earthquakes

  • and volcanic eruptions, and mining explosions, and even airplane crashes

  • Scientists have gotten to know these non-nuclear blasts pretty well

  • so when they saw large unusual disturbances beneath North Korea in 2006, 2009, and 2013

  • they concluded correctly, that these were nuclear explosions.

  • However, while all three wave techniques

  • waves in air, waves in water, and waves in earth

  • can triangulate the location of a major disturbance and even give some insight into its nature

  • a fourth technique is critical in order to know, for sure, if an explosion was nuclear or not:

  • Radionuclide Detection.

  • AD stations around the world sample the air for radioactive dust and gases

  • that are smoking gun signals of nuclear activity

  • which, combined with sophisticated atmospheric air flow modeling allows us to both

  • predict where fallout will disperse, and retrodict the general location of its source.

  • But in the case of a perfectly contained secret underground or deep ocean explosion

  • there might be no radioactive fallout.

  • So if seismographs and hydro-acoustic sensors pick up a suspicious signal

  • There's one final weapon in the international monitoring system's arsenal:

  • sending on the ground inspection teams to the actual location.

  • Except, inspection teams won't actually be legal until the treaty is fully signed and ratified.

  • *cough cough*

  • That's you, U.S., China, Israel, Egypt, Iran, India, Pakistan, and North Korea.

  • The world is waiting.

  • This video was made possible by the comprehensive test-ban treaty organization

  • though any political views expressed are my own.

  • Come on America, let's ratify the treaty now.

  • The CTBTO preparatory commission developed and implemented

  • the international monitoring system I described

  • and they're constantly seeking to improve the sensitivity of their sensors

  • and the sophistication of their data analysis.

  • They also make all their data available to the worldwide scientific community

  • so that other researchers can, for example

  • predict and monitor tsunamis, study the structure of the Earth, search for downed airplanes

  • do their own analysis of nuclear blasts, or track whale migrations, or meteors in the upper atmosphere

  • or radioactive fallout from nuclear power plant failures.

  • In short, the CTBTO is a collaborative endeavor of people around the world

  • using science to help prevent people from doing horrible things to each other with science.

  • And in the process they happen to be generating a lot of positive scientific side effects.

  • The CTBTO didn't ask me to say this, but after learning about their work

  • I want to thank them for making the world a safer place for millions, if not billions of people.

The Comprehensive Nuclear-Test-Band Treaty prohibits all nuclear explosions anywhere on Earth

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如何檢測祕密核試驗 (How To Detect A Secret Nuclear Test)

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    林宜悉 發佈於 2021 年 01 月 14 日
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