An analysis of all evidence relating to the chemical attack in Ghouta on August 21st 2013 - An online collaborative effort.
"It is very surprising that only 8 "victims" are burried, among them three without a shroud. Funerals, mourning and condolences have been almost inexistent. The neighborhood as seen in the map in the first page are not far than 3kms from the central Damascus. There is a continuous crossing from the civilian population from the so called "liberated areas" to the areas under the government control. The silence and, even, the social inconsistency of the reality of the "martyrdom" of the victims is an tricky problem. We think that there must be a "recognition" of the collective pits to be able to have an idea of the whole situation. But there have been no public burial, nor announcement by the Muezzin as usual. No condolences nor."أوغاريت ريف دمشق الغوطة الشرقية زملكا دفن شهداء مجزرة الكيماويhttp://youtu.be/LRDXgualsMw
Let´s try to also add the location when counting the victims. That´s important information to filter scenarios.
From day one I insisted that the Ghouta "incident" was nothing but a complex psychological operation.A massive chemical attack leaves a large number of casualties,material evidences.Yet,we have no proper body count,no post-mortem autopsies to clearly establish the cause of death, no definitive identification of the type of ammo & delivery systems used during the attack,no satellite imagery or communications intercepts.Nothing but speculations.Nowadays the most insignificant life event is captured on camera thanks to mobile phone technology.Where are the pictures of piles of bodies,of funerals,of graves?.Instead we have to rely on individual testimonies,hearsay (from selected individuals) & a couple of shadowy Youtube videos which provide no identification at all.This Ghouta "chemical attack" is a fairy tale.
I agree with you that it's been massively exaggerated, both in the number of casualties and number of dead. I disagree there were no Sarin casulties.MSF states around 3600 casualties with neurotoxic symptoms presented at hospitals. We know from Tokyo and Iran/Iraq war figures that the ratio of actual casualties to 'psychological' casualties is 5:1 so we prima-face get down to around 600 actual casualties.We know also that the vast majority of patients presenting with real symptoms do not die. Sarin kills in under 20 minutes - too quick to get to hospital. This puts the potential fatality rate in the very low triple digits. maybe 100 at the very maximumIt can be argued the already dead did not present, but we run into the problem of not enough bodies.I've been searching for videos of bodies in Ghouta, especially at funerals, and can find perhaps a few tens of unique bodies being buried. The largest number was at:http://www.youtube.com/watch?v=RhcbiJGU-Zk(Amusingly this was linked as 'hundreds of dead in shrouds')Counting up all the bodies I've seen I doubt the true death numbers were above 200 and are more likely nearer 100.Another useful figure would be persistent neuro-toxic symptoms. These were seen in Iran and Tokyo. We have very few if any of these and none of the continued reports that you'd expect if there were any significant numbers in this category.
Charles, my data suggests estimates of injured-to-dead ratio to be somewhere between 6:1 to 10:1. But, then, estimates do vary in literature. I think with the type of delivery vehicle (low dispersal and aerosolization), the estimated ratio of 10:1 is more likely. However, we run into the question whether or not it was Sarin (more on that later, to come) that was used. VX unlikely, but Tabun or Soman? In any event, other, less obvious CW agents would have different ratios.
Put on hat of "ex-micro-meteorologist"Dumping mostly liquid in a spot rather than a mist mostly affects the rate of conversion of liquid to gas rather than the plume shape and extentThe resultant plume of gas from a mist will be more concentrated but will also pass any individual location faster. A gas plume from mostly liquid will be less concentrated but expose any individual location for longer.Without running a model I estimate cumulative exposure down-wind would be similar in both cases, but maximum levels would be higher with a mist dispersal.I'm guessing that in the kill zone(s) cumulative exposure over a shortish period is at least as significant as maximum exposure for potentially less time.In summary. Mist or liquid may well get similar casualties but over different time-frames.
Charles & Gleb.I am not saying that Sarin was not detected, but I am questioning the very "intensity" of the attack.Despite Dan Kaszeta calculations which are based on the UN report data,I believe it is extremely difficult to evaluate the quantity of Sarin used in Ghouta. I think at some stage, Sarin was "released" to make it look like a conventional CW attack (probably following the Aum Shinrikyo Matsumoto modus operandi). Thank you for your feedback.I have been following your researches from day one,I think you are both doing an amazing job.
Gleb,Putting our figures together - potentially under 20% real casualties and potentially only 10% of those dead we are looking at 2% of reported casualties being dead.Going back to the MSM 3500+ casualty figure we get 70 dead for the MSM hospitals. Assuming they were only some percentage of all hospitals - I guess 50% - then perhaps 140 total dead.These figures are extremely rubbery but probably the right order of magnitude. So not 1400 dead nor 14 dead and with a target figure of around 140 dead.Ms Peel (or is it really Cathy Gale given your profession?) thanks for the comment.
oops not MSM, MSF!
Charles,Where do you get the death figures of MSF-hospitals? Can you give link to doc?
veritas,http://www.huffingtonpost.com/2013/08/24/doctors-without-borders-syria_n_3809955.html?ir=World3600 casualties, 355 dead.
Emma,I believe you are right - it is not only difficult, but virtually impossible to evaluate the quantity of Sarin used in the attack. It depends on asssumptions regarding (at the very least) (1) number of locations affected, (2) number of delivery vehicles used. I have no idea of what those number may be, only rough guesstimates.As for Dan, he chose to put his analysis in a deficient 800-word-limit format at Bloomberg. He has a fullsome article coming up. Let's see what that brings. I have been discussing various points with him by email, on and off.As for Sarin. Well, (1) I am not convinced Sarin is the, or is the only, cause of what happened; (2) UN Report is highly misleading in terms of what was detected. Consider the Appendices very carefully and determing exact analytical matches. Very illuminating. Biomedical samples are completely out of whack - not clear what was detected (Sarin detection impossible, breakdown - possible, but not in urine (not after 2 days, in any event), and, most likely, AChE levels were monitored, but many things are AChE inhibitors).Emma, and thank you for your comments. Much more to come. Keep a lookout.Charles,The analysis of number of dead is befuddling. I have no idea what to think. Let's keep digging.Best,Gleb
"…a target figure of around 140 dead."I've heard that number: "مقبرة جماعية في زملكا تم دفن 140 شهيد فيها من ضحايا الغازات الكيماوية 21-08-2013"If you want, you can watch this video (post "Count down", daybook on preview).
http://www.doctorswithoutborders.org/press/release.cfm?id=7029MSF says 355 dead (report of 24-8). The timing of this report (a few days after the attack, but before the american report which has probably biased a lot of people) would permit an objective effort of counting (does not mean it is correct...).
I tend to doubt the MSF figures - especially for the number of dead. It's just on 10% of total reported casualties.Given the rapid action of Sarin, if you get enough to be fatal you die pretty well straight away. Certainly the vast majority are dead inside 20 minutes, most in the range 5-10 minutes. Most would die well before they could be taken to hospital. Those who do make it to hospital are unlikely to die as it would be 30 minutes up to hours after exposure.The MSF figures are from MSF 'associated' hospitals, not MSF run hospitals. Some degree of bias in the reporting from the hospitals is to be expected.
Charles, agreed, with one clarification - my literature indicates fatal systemic exposure could (and should) cause death in as little as under a minute. Depends, of course, on AChE levels (vary greatly in humans, and hence problematic indicators of Sarin exposure) - with high AChE levels you will have strange results of individuals surviving very high, supra-lethal Sarin exposure levels (as per Tokyo literature).I am wondering, how does malnutrition, bad nutrition, PTSD, stress, poor hygeine affect AChE levels - I suspect either no effect or detrimental effect.Questions.
Charles,I agree MSF wasn´t there and they are probably biased in favor of the rebels. But this page is about gathering facts and evidence. The MSF adds to the evidence that not 1400 people died, but probably less than 355.
Due to the meteorological conditions & the nature of the terrain-environment,I am even questioning the fact that anyone died as a result of exposure to Sarin
Sorry to contradict you, but several careers ago I was a micro-meteorologist specialising in the transport of gases, especially in still night conditions. It was primarily to make sure environmental exposure limits weren't exceeded under observed weather conditions, but also to find out how many people would die in certain types of gas release - pretty much ideal work for understanding CW releases.The night in question - using Damascus Airport data - had ideal conditions.That is, it was a clear night, the breeze was quite low speed, and the surface temperature was around 20C. An inversion would have formed for sure. That is, it was coolest at ground level and got warmer with altitude up until a specific level called the inversion level when the temperature got lower with further altitude. It was perhaps 30-35C at the inversion level. which would have been 50 - 150 metres above ground level.In an inversion gas doesn't rise normally by convection. It can rise by diffusion over a period of time but not as big buoyant parcels of air/gas.So what you will see is a layer of trapped gas under the inversion, most concentrated at the release point but getting larger and more diffuse down-wind. There will also be some mechanical turbulence to speed up the diffusion.So, very close to the release point, people maybe 20 metres on either side wont be affected. As the gas is drifted down-wind by the breeze it will spread sideways and also vertically. You get a cone of death spreading out downwind. People in higher levels near the release my not even have any gas exposure. People further downwind will have exposure on higher stories and also further to left and right.After a period/distance downwind the gas will have spread out so much that it becomes not lethal.What you would expect as I said is a cone of death, more visible as a wedge of death that gets wider and wider until it stops having an effect.A factor on how fast it works is whether the gas is dispersed as a mist or as a liquid. Mists evaporate faster and produce higher concentrations more quickly. Being mist the release location is probably of greater vertical and horizontal extent at the start than a liquid source.The story about Sarin gas being denser than air is a furphy. By the gas laws, Sarin, Oxygen, Nitrogen, water vapour etc are independent gases and behave as though each was there on its own. There will be some penetration of basements but only as a result of diffusion.So in summary. Cone of death. Limited areal deaths near the start. More areal deaths downwind. No preference for basements. Higher story deaths further downwind.
Charles.Do you remember the specificity of the Aum Shinrikyo Sarin attack on the Tokyo Subway?.The large number of casualties was the result of the nature of the environment.1)the diffusion & the propagation of Sarin was facilitated by the air conditioning system,the temperature of the locations & the architecture of the underground infrastructure.2) If I remember correctly,the perpetrators released Sarin inside the wagons, the mode of release was done through plastic bags.The nature of the environment in Ghouta is totally different.It is an open air location with building,housing complexes,which hinders the release of Sarin at ground level (especially if the Sarin was released through conventional airborne delivery). I (humbly) believe that the particular meteorological conditions also play an important part in the process.
Charles, I actually disagree with you.As we all well know by now:(1) Sarin is not gaseous at most commonly experience temperatures. It is delivered usually through some means of aerosolization.(2) Sarin, even aerosolized, is heavier than air, it will condense, and it will descend on surfaces, rather than remaining buoyant.(3) The lower the temperature, the faster Sarin will condense.(4) Under inversion conditions, Sarin will descend on cooler solid surfaces and condese even faster.(5) The delivery vehicles were very imperfect. I would be surprized if they managed any real aerosolization.(6) The delivery vehicles exploded at ground level, not higher up. The rate of descent/condensation would have been ever more likely.(7) etc.All in all, in my opinion, the meteorological conditions are rather irrelevant - they do not assist the hypothesis that the weather made Sarin a more potent killer in the circumstances. UN was likely raising it for the simple fact that it is traditional military doctrine to use CW at night, precisely to use the "inversion" factor. Except, in this case, it was irrelevant.Plus, the fact of a 7 km/h breeze would have prevented Sarin from pooling in one area, likely assisting condensation and descent.
Gleb,I guess we'll have to disagree. Much of what you said about atmospheric processes was wrong in one way or another. Mainly you say what seems intuitive rather than what actually happens.I was going to give a long treatise why, but it would be very long, complicated, and probably not convincing enough for you.In brief summary, for the gas releases I investigated it was a very safe assumption that the gas would exist at below saturation level and at ambient temperature within in seconds from release or with a fairly short distance. I looked at a wide variety of gases with different density, saturation vapour pressure, and temperature. e.g. accidental spills of methane in liquid and gas form.Gases including Sarin will only condense when the vapour pressure reaches the saturation vapour pressure in some location. That usually is a strongly radiatively cooled surface - which would be in fairly short supply on a 20C ground temperature night with a 2m/s breeze.Sarin does not 'descend' unless it loses energy by cooling. There were no cooling processes available after the initial evaporation of the mist or liquid. Once in gas form it keeps on being in gas form until something cools it. However, while in gas form it diffuses in every direction - think of an expanding balloon - the Sarin occupies more and more volume but at matching lower concentration.
Ms Peel,The weather conditions were very important. Primarily the slow breeze meant the gas was kept reasonably concentrated downwind because there was little mechanical turbulence to mix it with ambient air.There was also an inversion - where temperature increases with height. That makes it thermodynamically very difficult for parcels of gas to rise. This in turn means that gas stays more or less at the level it was released. In contrast on a hot sunny day where the temperature decreases with height, parcels of gas get heat from the ground and rise like buoyant bubbles through the cooler air above.Net result: lots of gas in the lower 5-10 metres of the atmosphere in a reasonably narrow plume downwind - perhaps disturbed a bit by buildings in the way.
…the gas would exist at below saturation level…"Sarin, or GB, is … a colorless, odorless liquid…"Could sarin evaporate when hitting barrel on the ground?
@Charles Wood – Re: "There will be some penetration of basements but only as a result of diffusion."The first responders reported heavy concentration of victims and gas in basements:According to local doctors, some people took cover in basements, where the gas settled and suffocated them. Medics and photographers who had become accustomed to rushing to the site of attacks arrived too quickly, succumbing to the gases themselves.If what you are saying is true, then any concentration of gas would mean a local release, possibly in a confined space.See Role of Basements on our wiki.
Petri,I am highly suspicious of that report. It sounds like they were reading wikipedia.In any gas attack the safest place to be is in an enclosed space. This is in all the civil defence manuals. In Israel in particular they issued gas masks, plastic sheeting, and masking tape to seal up rooms.Unless there was some positive action to suck air into a building, gas will drift past and any that does enter the building will be at very low levels.Sarin at typical vapour pressures obeys the ideal gas laws. That means it doesn't rise or fall in relation to ordinary atmosphere gases. It simply doesn't 'seek out' lower ground.The only exception to this is if the Sarin is in an aerosol form and the particles descend under gravity. This would be highly unlikely beyond a few scores of metres from impact point.
Charles, I think you are misunderstanding me. I am engaging in this dialogue prepared to be convinced. And, you are correct, my conclusions are intuitive by and large, based on what I understand of the entire matrix of issues and my own knowledge (however rudimentary) of physics and chemistry involved.You are also correct that I am not entirely convinced, but I stand to be corrected. It would, in fact, help to have a longer treatise on the subject, inclusive of the papers/data you referred to. I have not ventured down this line of analysis yet, and you clearly have. So, please do share.
Gleb,I've started downloading some computer modelling software to demonstrate my points - my computer models were in the 80s and not as sophisticated as present ones, though surprisingly the methodology hasn't changed much.I'll run some simulations and post the results. It would be helpful if I could get precise locations of alleged impact points / release points if anyone has them?
Try thishttps://maps.google.com/maps/ms?msa=0&msid=212756140828939152569.0004e471308e20c96030eimpact sites are the blue pins in zamalka + the blue cloud there + the red fire sign
Gleb,For you amusement while I do the modelling stuff, here is a video of an accidental gas release.http://www.youtube.com/watch?v=sNkdAs1e7CwWithout looking at wikipedia, is this gas heavier or lighter than air ?While you are at it, and again without looking at wikipedia, is humid air more dense than dry air or less dense?Odd questions, but relevant to intuition vs physics.
Thanks for the test. It's been a while since I've been asked to take one.(1) The video shuts off before the gas is released, so can't comment on what's in the video. However, the caption identified the substance as anhydrous ammonia, which I presume is what's shown in the video if it played properly. Anhydrous just means that it's "dry" - i.e. devoid of water. Common ammonia we use around the house is dissolved in water, hence stays as a liquid (although it does vaporize, hence the smell). I tend to recall, although very vaguely, that ammonia also interacts with air - oxidizes with oxygen, maybe?Anyways, I can't tell you what my intuition would be regarding physics from observing the video. I think ammonia is made of, hmm, hydrogen and nitrogen? Hence, based on the gases that air is made up of, I would hazard a guess and assume that ammonia gas is lighter than air.I assume that in the video you wanted me to see - ammonia was settling on the ground or something like that? Or it was not rising up? Anyways, ammonia has a great time with water - hence why we can dissolve it in water and keep it around the house - so I would assume how it behaves in the atmosphere would have a lot to do with how humid it is on that day.Ammonia, as a "natural" gas - i.e. a substance that stays in a gaseous form at most common temperatures we experience - probably goes from liquid to gas at below-zero temperatures (for clarity, I think in Celsius). So, how it would behave would also depend on the temperature that day.Beyond that, I can't tell you more, as I haven't seen the video.(2) As for humid air and dry air - it's dry air that's denser. I am not explaining why, man. You know why. ;)The only caveat, of course, is I have assumed that both humid and dry air in your question are at the same temperature.Cheers.
Gleb,Sorry the video cuts off for you. It works fine for me. Perhaps you could view the part 2 linked to it?Getting useful models is proving difficult. They are all old hoary Fortran things and not particularly relevant to short term point sources over time-scales of minutes. I'll still keep looking, but for now here is some homework for you.Use of models in gas emergencieshttp://aevnmont.free.fr/SACH-BOOKS/Petrochemistry/Handbook%20of%20Hazardous%20Materials%20Spills%20Technology/Part%20V.%20Spill%20Modeling/17.%20Practical%20Uses%20of%20Air%20Plume%20Modeling%20in%20Chemical%20Emergencies.pdfAerosol processes for a variety of chemicals (not including Sarin, but some similar)http://aevnmont.free.fr/SACH-BOOKS/Petrochemistry/Handbook%20of%20Hazardous%20Materials%20Spills%20Technology/Part%20V.%20Spill%20Modeling/27.%20Modeling%20Atmospheric%20Dispersion%20of%20Heavier-than-Air%20Clouds%20Containing%20Aerosol.pdf(The authors of the last one have published data on Sarin, VX and Mustard gas, but it's behind a pay-wall)Regarding my test questions. Anyhdrous Ammonia is a lot lighter than air with a molecular weight of 18, compared to O2 at 32 and N2 at 28. In the video it wasn't rising because what you see is condensed water vapour forming an ammonia water mist that is also very cold due to Ammonia evaporation.You got the trick question right. Water vapour H2O has a molecular weight of 18 - the same as Ammonia NH4. Most people think that because air is humid it must be heavier due to all the water in it.
Charles,I think I know what went wrong with the video - my work network restrictions. Will have a word with my IT guys to tell them to mind their own business, rather than monitor my youtube usage.Lots of reading - but it's fun stuff. My bibliography is growing all the time.Test questions:(1) Re NH4 - funny, that was one of my guesses, as you saw. Makes sense.(2) Yeah, Charles, someone with Soviet highschool education knows a few things others in my position would not have. Hence why I refused to give you an answer to the trick question, but gave you a hint (comment on temperature) that I knew why.I'll give you a cute trick question of my own (don't be offended, I am just being silly and having fun):(1) The vapour pressure of IMPF at 20C is 2.10 mm HG;(2) The vapour pressure of Dihydrogen Oxide at 20C is 17.5 mm HG;Question: which of the two substances would evaporate at a faster rate given the same atmospheric pressure, same temperature, but provided they are present in the same confined space and evaporating at the same time? What would be the product of co-vaporization?Cheers - and it's a pleasure having this dialogue!
Not knowing what IMPF is - I'm guess Sarin ? Your question can't be answered without more information. To be precise latent heat of vaporisation.Your other chemical, Dihydrogen Oxide (incidentally the most lethal chemical on the planet) has an extremely high latent heat of vaporisation so under the same conditions of temperature, pressure, and heat supply it will evaporate more slowly than many chemicals.Guessing again that IMPF is Sarin, anecdotal evidence says it evaporates faster than water under the same conditions.I also need the existing vapour pressure as that has an effect on evaporation - e.g. water will not evaporate at 100C if it is in an atmosphere of 100% humidity - to be precise exactly as much condenses as evaporates at any instant.So assuming 'dry' air (water and IMPF vapor pressure low) the IMPF is likely to evaporate faster.Co-vaporisation? Unless there is a chemical reaction between the gases then there will be no effect - Perfect gas laws apply. The only anomaly is that total pressure is the sum of the two gases.You state a confined space - does that mean pressurised? If so, the pressure of the combined gases will affect the evaporation rate of both liquids.If it is a confined space but vented then they will evaporate at whatever rate set by atmospheric pressure, ambient temperature, and available energy to change phase.P.S. I'm waiting on a key for a commercial software air dispersion model.
Interesting, mostly as I expected, but not entirely.(1) IMPF is Sarin, correct.(2) Anecdotal evidence is incorrect with respect to relative volatility of Sarin and H2O - in fact, their volatility is approximately the same.(3) Sarin and H2O will evaporate at approximately same rates, given same temperature, pressure and other relevant conditions.Source: http://cbwinfo.com/Chemical/Nerve/GB.shtml(4) Some data on vapour pressure. At 20C:Sarin - 2.1 mm HgH2O - 17.5 mm HgAnother source on nerve agents:http://www.gulflink.osd.mil/library/randrep/mr1018.5.appb.pdf(there is a typo there on Sarin volatility, ignore, Sarin volatility at 20C is 16.091 mm/m3)(5) Volatility will obviously depend on multiple factors for each given compound.(6) There will be hydrolysis of Sarin in H20 vapour, producin IMPA and HF. Hence the question about "co-vaporization" - better = simultaneous vaporization.(7) Correct, sealed space. Correct, will have an effect.Look forward to more!
Just for clarification, the substantial margin of difference in vapour pressure between H2O and Sarin would result in approximately the same rate of evaporation at similar environmental conditions, notwithstanding any other endogenous factors, such as high latent heat of vaporization.
But what you have not considered (and perhaps the effect is marginal), is what effect the energy requirements for water vaporization would have on the vaporization rate of Sarin when vaporization is simultaneous and occurrs in a confined, sealed space.
Gleb,I'm still working on a model. but this very imperfect report by Postel has a section on likely lethal zones. Essentially he surmises a kill zone of 2500m from impact in a fairly narrow band. He also assumes a 2m/s wind speed which is only true around midnight local time. By 3am it's around 6 m/shttps://graphics8.nytimes.com/packages/pdf/world/syria/iraq_syria.pdfSee also http://acloserlookonsyria.shoutwiki.com/wiki/File:OSDI-spd-dirn.png
Our wiki has been kind of offline for the last week as they were moving servers, but it's back now. Our main article has (at least on this topic for a change) some useful information, and Caustic Logic has done some legwork on our talkpage on the subject. For me the most credible account seems to be the one of the Center for Documentation of Violations, with around 500 victims, most of them named and many with photos. See here for details on the CDV data. That number is roughly on par with what the SOHR claims - who complained that the US was exaggerating numbers, which is quite remarkable as that outlet has been the default go-to "expert" for all things Syria numbers in the Western corporate media for most of the crisis, and often accused of exaggerating themselves.
And, finally, the ’’red line’’ affair. According to the joint committee of the British Intelligence service, Jon Day, Syria would have supposedly used combat gas 14 times in the past. But this was never confirmed. Why 14 times before? Because it is the number of times the US government had use of chemical weapons in Iraq, in 2003-2004. And, of course, it would only be the 15th time of use that would lead the punishment exerted by the great powers.