South Korea reports that Kim Jong Un has offered to close North Korea’s nuclear test site at Punggye-Ri in May. He says he will invite US and South Korean experts to examine the site before its demolition to see that it is still usable.
There have been very definite statements from experts outside North Korea that the site may or may not be usable. We don’t have access to the site, so we must surmise the situation from overhead photos, seismic traces, and experience at other test sites.
The yield of the most recent test was very large, perhaps 250 kilotons. It’s hard to estimate the yields of North Korean nuclear tests because we don’t know enough about the geology of the test site. It was followed by three seismic events of 4.6, 3.5, and 2.9 magnitude, which were not tests.
An underground nuclear test forms a cavity; the larger the yield, the larger the cavity. As the cavity cools, the ceiling collapses and forms a chimney filled with loose rock. A crater may form at the surface (diagram) and video.
The aftershocks could be the cavity collapsing in stages, or they could be the cavity and tunnels collapsing. Or it could be things happening in the rest of the mountain, as the jolt of the blast destabilizes things. It could be that the blast also fractured rock throughout the mountain. Landslides can be seen around the mountain, and its surface contours have been altered.
None of this is extraordinary for nuclear test sites. To say that it represents the mountain’s collapse is an exaggeration, as is the phrase “Tired Mountain Syndrome.”
A few articles have indulged in scare talk about radioactive material escaping from future tests. That would be a mostly local concern, if indeed the mountain is so fractured. There would be no point to another test where the chimney has formed, and North Korea has additional tunnels in other places in the mountain.
It’s likely that the North Koreans would find such an escape undesirable for other reasons. They have been extremely careful to contain their tests; escape of material would allow other countries insight into the design of their nuclear weapons.
US intelligence officials have said that the test site remains operational.
Closing the site would probably involve dynamiting the tunnel entrances. The tunnels could be opened in the future. North Korea destroyed the cooling tower for their plutonium reactor in 2008, in a similarly symbolic gesture. They built it back later.
Even if the test site were damaged, that is likely a small part of Kim’s calculation in offering a pause in testing, and even a closing of the test site. The larger factor is that he feels that he now has a deterrent against American and South Korean attack.
Cross-posted at Nuclear Diner.
RepubAnon
It’s nice that North Korea is making this offer – but I expect they wouldn’t let outsiders see enough to verify that the site was truly unusable. It could also be that the Chinese objected to the possibility of radioactive leaks from the site drifting over into China.
Long story short: these treaties remind me of the Firesign Theater skit:
Frankensteinbeck
I consider them mostly trustworthy on an issue like this, and it’s an important issue. Thank you.
Suzanne
This brings out my inner Admiral Ackbar, man.
Brachiator
I’m seeing a current(?) story that North Korea is making promises based on a US promise not to invade.
From the New York Times. Don’t know how to get through their paywall from my cellphone.
How should the US respond to this?
RepubAnon
Link to the New York Times: Kim Prepared to Cede Nuclear Weapons if U.S. Pledges Not to Invade
Cheryl Rofer
@Brachiator: With caution.
I can make a case (and started to last August) that Kim is making a concerted move toward peace talks and something to do with nuclear weapons. His comments along this line have been reasonably consistent for some time. A few of us are discussing it on Twitter – check out Vipin Narang’s timeline in particular.
Kim has talked about such things before. He’s talked about nuclear disarmament in a way that can be read as “We’ll disarm when you do.” He may be trying to take a high road similar to India’s on this: “We only have the damned things because others do.” His talk so far is pretty general, with no implementation details.
That said, I would test it. That would involve lower-level talks to see if flesh can be put on those bones. Right now, it looks like he and Trump can come out with a very general statement and no results. But one of the things Kim is doing is setting himself up to look like the good guy when Trump acts like a jerk.
Cheryl Rofer
That headline is a wild overstatement.
sdhays
@RepubAnon: That sounds reasonable to me (depends on the details, of course), but I’m pretty sure they could have gotten that deal years ago. So what has changed? Is it really just as simple as they now feel that they’re negotiating from a position of strength?
sdhays
@Cheryl Rofer:
So, low-hanging fruit.
Brachiator
@Cheryl Rofer:
But the US has already pulled its nukes out of South Korea. Would a promise not to invade involve pulling out troops from South Korea or decreasing military support for that country?
Trump needs to play up his ability to do a deal. This would be his first substantial foreign policy test, and the GOP and Trump supporters are already pushing the idea that Trump’s white man toughness has already been instrumental in getting North Korea to make concessions.
ETA. I’m wondering if Trump will screw things up by towering over the North Korean leader, or making some crass comment about his height or weight. On the other hand, the North Korean advisers have to be considering some way of assuring that their leader does not appear to be diminished.
Also, too, Kim’s sister appears to be a key adviser and major player. I wonder how US officials will deal with her.
the Pale Scot
@RepubAnon:
Cheryl Rofer
@Brachiator:
We don’t know what Kim has in mind. He seems not to be convinced that the nukes are out of South Korea, and he is VERY concerned about US overflights of South Korea from Guam, which take place regularly. The Guam B-1s can’t carry nukes, but if you were Kim, what would you think when American planes head toward your country?
Trump needs to up his game so that those of us who are not in his thrall believe he can do a deal. Nothing he has done so far suggests that is possible.
Trump’s insane tweets and the phonecall to F&F probably convince both North and South Koreans that this is not a man who should have control over nuclear weapons.
The nature of a summit meeting is that both parties have materials prepared beforehand and stick closely to the script. Of course, Trump hates 1) listening to other people, including those who would help him prepare, and 2) sticking to a script. Not auspicious.
Kim’s sister is only a woman. Compare to Angela Merkel’s visit last week. Probably some people in those still left at State have some ideas about what her influence is and how to deal with her, but it’s not clear anyone above them is listening.
J R in WV
@Brachiator:
“But the US has already pulled its nukes out of South Korea.”
Yes, removed them to the aircraft carrier strike groups and undetectable submarines just off the coast of Asia, within easy striking distance. Not to mention the bomber groups based on Guam and Diego Garcia.
Cheryl, about that short video of subsidence following an underground nuclear test… was that event immediately following the explosion, or after the actual event with slow crumbling in the “chimney” above the opening created by the explosion?
I’ve spent some time watching a wide variety of video from the Nuclear testing age, there are amazing scenes captured and now being released to public viewing. I don’t know which are more interesting, odd failures with strange patterns or the completely successful major tests with super slow motion film now available. Glimpses of another universe, almost.
Another interesting video is the time lapse film of every atomic explosion in the world, ever, by Japanese artist Isao Hashimoto. He shows the 2053 detonations from 1945 to 1998, all but the recent tests by the DPRK. In 14 minutes, with sound effects, on a map of the world, identified by who’s bombs were going off. Surprising where some of them went off!
Brachiator
@Cheryl Rofer:
No one appears to know much about Kim, apart from his previous bluster. Are his military advisers smart? Does he get briefings from the Chinese? Does he listen to them?
What do intelligence officials know about Kim and his assessment of US and South Korea military strength?
This is true, but GOP leaders and strategists are pushing hard on the idea will not only get a deal done, but also that Iran will be so shocked and awed that they will immediately seek Trump’s favor.
The GOP needs for Trump to be able to show that he can get something done. Perversely, North Korea may see an advantage in making Trump look good, if it serves their purpose.
BBC news reports included interviews with people in South Korea and in South Korean communities in California who were giving Trump a lot of credit for helping to thaw relations between North and South Korea. This also included a South Korea government official.
Damn. It will be sad and stupid and dangerous if the White House gang underestimate Kim’s sister.
Major Major Major Major
@Brachiator:
It’s in Kim’s best interests to make Trump think this, too.
Cheryl Rofer
@J R in WV:
IIRC, subsidence at the Nevada Test Site was usually within a few hours of the shot. It depends on the geology of the site.
ARoomWithAMoose
Could it be the Chinese came forward with an offer of further economic support for NK on the condition of descalating things on the korean peninsula? The Chinese have other strategic concerns (their claim on a big chunk of the south china sea), getting more US assets out of the area would certainly reduce our interests in contesting/ability to contest that.
? Martin
I fail to see how Kim isn’t coming out ahead here. NKs entire strategy has been to present sufficient threat to keep the West from intervening in their politics. Now that they’ve demonstrated a functioning nuke, they’ve hit the pinnacle of that strategy. They wanted unilateral talks with the US, and they’ve got that. They don’t want the capability to destroy the US, they know they can’t achieve that. They have just enough power to be treated with the respect they always sought. There won’t be regime change, and Kim can now shape the country as he wants.
Yutsano
@Cheryl Rofer: The article also identifies Pompeo as Secretary of State. Now I am still in surgery recovery and all but I don’t remember seeing his confirmation vote. More sloppy writing or did they drop the acting intentionally?
Brachiator
@Yutsano:
Yutsano
@Brachiator: Huh. Guess I did miss a few things.
Brachiator
@Yutsano:
No sweat. Hope your recovery continues to go well.
J R in WV
@Cheryl Rofer:
No doubt every explosion was different, every site’s geology was different, that’s the nature of testing. Thanks for the feedback.
That’s why we have millisecond film of all those squib shots, testing done right means some won’t go quite the way you expected, some won’t go at all the way you expected. And some look like doors into another stranger place.
Cheryl Rofer
@Yutsano: The senate voted to confirm Pompeo as Secretary of State on Thursday. Wasn’t that when you were having surgery? Hope you’re doing better!
ETA: I see Brachiator beat me to it!
Bill Arnold
@J R in WV:
That video is definitely best watched at 2X. Thank you for the link.
Cermet
Now that kim has a city killer hydrogen bomb, fully proven and tested, and just as powerful as ours, along with an ICBM that can deliver said nuke to anywhere in the US, of course he can negotiate and even promise the test site shut down (just like we already did many years ago – big deal.) He has the leverage now – over and above a million plus man army, vast number of artillery pieces in a vast array of tunnels that can destroy Soul in little time. Realize he has the full backing of the orange fart clouds best bud, putin, too. This whole show is a joke but he knows full well, via his sources in the Kemlin, that the fart cloud can easily be manipulated into a deal that gives away nothing and gains what ever he can negotiate. We are looking more and more screwed – wait, at least the fart cloud can kill the Iranian deal using success with kim as a counter-weight; wait, we are even more screwed..