Turkey's earthquake and China's balloon

Plus, the overlooked threat of indoor air pollution, and the newly deciphered letters from Mary Queen of Scots
10 February 2023
Presented by Chris Smith


Cracked Earth


As Turkey battles against the clock to find survivors of the recent Earthquake there, we look at what triggered the magnitude 7.8 quake. Also, how modern day codebreakers have unlocked secret correspondence penned by Mary Queen of Scots from exile in the 1500s, and the overlooked threat of indoor air pollution: we worry about what we breath in on the streets but we’re potentially encountering air just as bad in our own homes…

In this episode

Crack in earth

01:06 - What caused the earthquake in Turkey?

What were the underlying reasons for the 7.8 magnitude earthquake, and what can be done to prepare in future?

What caused the earthquake in Turkey?
James Jackson, University of Cambridge

Turkey and Syria were hit by a devastating earthquake measuring 7.8 on the Richter Scale. More than 11,000 people have been killed, and many more are still unaccounted for. With us to explain what caused this to happen and what else might be in store is geologist and earthquake specialist James Jackson, from the University of Cambridge.

James - This has happened in Southeast Turkey along near the border with Syria. And it's a part of a very well known fault system, which we know a lot about. And it's there because Arabia is pushing North into Asia, crumpling the place up moving at about two centimetres a year, and Turkey is sliding out of the way sideways on a fault - think like a knife cut where rocks slide past each other sideways and Turkey is moving to the west out of the way of Arabia, which is moving North.

Chris - And how often do these sorts of events occur there?

James - There, I think the last one was around 200 years ago. But we know a lot about the history of that part of the world. People have lived there a long time. And if you go back over the last thousand years there have been quite a number of this sort of size. So it's not in that sense of surprise.

Chris - Is that because people have documented this or are there other records of how this happened?

James - It turns out that the various empires that ran that area, like the Byzantine Empire, the Ottoman Empire, were totally bureaucratic. And when these things happened, the emperor would send out parties to go and describe what had happened and it would all be recorded in the records and people have been through all that sort of thing.

Chris - So in essence then, if it's 200 years since it last slipped, that's 200 years worth of two centimeters a year movement and slippage which has been stored there and has gone all at once.

James - Yes, indeed. That's why it's moved. It'll have moved between five and 10 metres sideways.

Chris - So it's sort of horizontal. It's not up and down?

James - It's not up and down, it's sideways. If you are standing on one side, the other side moves to the left. That's how it works. We know a lot about this particular fault. It's been studied quite well.

Chris - How far out from the area where the slippage happens will the repercussions be felt? How far does that energy propagate dangerously?

James - You don't want to be really within about 20, 30 kilometres, there's quite a difference in terms of which direction you're in. So these things rip like a piece of paper and they rip from one end to the other and this one started in the South West and ripped up towards the North East. And in the direction in which it's moving like that, you get about twice the ground shaking. And that's why most of the damage is to the North East towards Kharamanaras and other places up there.

Chris - And once it goes, does it tend to release all the energy all at once or could there be more in store?

James - No, it ruptures about two kilometres per seconds. So this would've taken about a hundred seconds to do its stuff. So if you've been anywhere near it, you wouldn't have been able to stand up for a hundred seconds.

Chris - But if you've got 200 years worth of energy stored there, does it release 200 years of energy in one event? Or does it go and then wait a bit, couple of days go by and then...

James - You get after shocks. If you have a crack in the windscreen of your car, you know where it's going to go next. And all that's happening is a crack is releasing the stress by the crack and it all concentrates at the end of a crack. And that's what happens while you get aftershocks around these faults.

Chris - So is it done now or are Turkey bracing themselves? There may be more in store?

James - There'll be aftershocks from this earthquake for a year or so. They're not necessarily destructive and they should be smaller than the two we've just had. But on the other hand, they're going to hit buildings which are already damaged and vulnerable.

Chris - Right. And how will geologists like you now be studying this because every event like this, awful as it is, is a learning opportunity. How are people beginning to piece together what's going on?

James - Within a day or two we will know precisely what happened, where this fault moved within a meter, how much it moved within about a metre along its entire length. We can get that information from satellites. So satellites come over and they take a before and after picture, essentially, of the land, either with radar or optically, and you just compare the two and you can see how it moved.

Chris - And does that inform what might be going on next?

James - We do it because we want to know how these things work. You learn from it as you say, by doing this. Someone has to actually decide what you can learn. And the result of all that is that we can't say when the next earthquake's going to happen, but we are quite good at saying what will happen when it happens - in terms of the shaking, the distribution of the shaking, whether it moves up and down or sideways, all this kind of stuff, which is what the engineers and architects want to know. So if you then give that information to the engineers and architects and say, can you build something which will stay up? The answer is yes.

Chris - The classic line is it's not earthquakes that kill people, it's buildings. The number of lives lost here though seems dramatic. Is that just a reflection on how many people live there or is that just a reflection on how serious the event was?

James - It's not large compared to some of the past ones in Turkey. I mean, it is about right for this kind of earthquake in Turkey. And it's a tragedy. I mean, the same size earthquakes in places like Chile and New Zealand are not about killing people in these numbers at all because their buildings are better.

Chris - Is that because they haven't had one every 200 years, so they pay more attention?

James - So you'll feel one which scares you every year, and every 10 years we'll get one which really scares you. And then every lifetime you'll get one this kind of size.

Chris - And that focuses political minds. So buildings are built better, people are better adapted and prepared?

James - If you talk to people in that part of Turkey, and you say the last one was 200 years ago, they'll say every day it takes me two hours to get to work, to collect my children from school. I have problems with traffic, congestion, pollution, water supply. There's a war going on. And 200 years ago, it's a problem for my grandchildren's grandchildren. It just has very low priority. And that's the real difficulty. And that's because of the geology. It's because there are lots and lots of faults in Asia and each one doesn't have to move as often as around the Pacific.


07:11 - New decoded letters from Mary Queen of Scots

50 letters from Mary Stewart have been discovered and deciphered

New decoded letters from Mary Queen of Scots
George Lasry, DECRYPT

‘A stunning piece of research … these discoveries will be a literary and historical sensation.’ The words of University of Cambridge Tudor historian John Guy on work published this week detailing newly-deciphered coded correspondence penned by Mary Stewart - Queen of Scots. History buffs will know of Mary, Queen of Scots’ role in a plot to overthrow her Protestant cousin, Queen Elizabeth I, and restore Catholicism in England. This new find sheds yet more light on the machinations to seize the throne by unpicking the meaning of Mary’s invented graphic symbols by looking for the intricate patterns hidden in the text she wrote in the 1500s. This was a very popular way of keeping messages between trusted allies in the Early Modern era private. Cryptographer George Lasry spends his time poring over national archives in search of documents written in sophisticated codes, “cyphers”, in the hope of solving something of historical significance. James Tytko asked George what it felt like to have contributed so significantly to modern study of this fascinating figure…

George - Surreal. We could not believe our luck and we needed to do a lot of checks to make sure that we are not dreaming or inventing stuff. But eventually we were very much convinced that this is for Mary Queen of Scots and the fact that we can contribute to the history. Folks like us, we are passionate about historical ciphers and we like to crack them. But when we reveal such exciting and new material, it's really, really gratifying.

James - Yes, I can imagine this must be the absolute holy grail for someone with your passion and interest. How long have you been interested in solving ciphers?

George - So I've been always fascinated by history and by the world of intelligence and I'm also a computer scientist. So I like a lot of mathematics and algorithms. So cryptography and cracking ciphers actually combines all of them together. About 10 years ago, I decided to put that hobby and interest into some academic work and I started to crack some historical ciphers and to write papers. And then I wrote a PhD on the subject. So it was very fun, PhD. But nothing of this magnitude. When we look at ciphers, it's kind of a passion and an obsession. <laugh>. When we see a cipher, the moment the cipher is there in front of us, then literally we cannot go to sleep until we solve it.

James - You didn't know what you were working on until you sort of started to translate them. Where did you find them? Why hadn't texts of such historical importance, obviously people didn't know they're of such historical importance, but why hadn't they been looked at and cracked before?

George - So first there is evidence that some of those letters existed. There are, for example, other letters that are referenced, specific letters which are missing. So historians had an idea that something is missing here, but no one knew where to find them. And we find them really by chance because we are part of a project which is called the DECRYPT Project. It's a project involving multiple universities in Europe to collect and then digitize and transcribe and decipher documents in cipher that we have in national archives, like in the Bibliotheque Nationale de France or in Germany and Italy and so on. And we just collect ciphers and if they're not yet deciphered, then you will crack the code. But we do that systematically. And also if you look at one of those samples, all you see are graphical signs. There is nothing to hint about who wrote them to whom, and the date.

James - How sophisticated were cyphers from this Tudor period. And what did you have to therefore do to be able to crack them?

George - If we look at ciphers we use in France or in England, the one that Mary Stewart used was by way to communicate with our ambassador, the French ambassador to England, Michel de Castelnau. So it's more direct, it's not the strongest one, but it's a good one. It's a secure one. For an historical codebreaker, we used the computer in the process. So it took us less time. Still the work required not just a computer to give us a head start, but also a lot of manual analysis of the text. A lot of linguistic analysis, a lot of textual analysis.

James - I see. So now is where you sort of pass the baton onto the historians to get their teeth into it. So we, I suppose the significance really of this find is sort of yet to be revealed in a way.

George - Yes, we did go over all the texts and we summarized them in our paper. So we know more or less the subject that they're talking about. But only historians which are deeply knowledgeable about the matter will be able to give us the full significance of each one of those details that we have. We have many names. Some of them are known to historians and some of them are not known. Events are reflected in various ways, sometimes very, very colourful. And we have about 50,000 words. 50 letters with 50,000 words. Sometimes even if you find one letter from someone like Mary Stewart, that's a celebration for the historical community. But 50 letters and some of them are very long. It's a real gold mine. We think.

James - So interesting. And has this satisfied, George, your appetite for cryptography for the foreseeable future or I can almost imagine the answer to this question already. Are you more energized than ever?

George - Yes, and unfortunately it's, it's an addiction. And it's not something that you can <laugh> you can put on the side. And we still have a lot of stuff to work on. I'm very much in doubt if any of them will be at the magnitude of deciphering 50 letters from Mary Stewart.

Vaping could cause popcorn lung...

13:37 - The fight against indoor pollution

Indoor pollution is responsible for as many deaths as outdoor pollution, but goes unnoticed

The fight against indoor pollution
Ally Lewis, University of York

Bad air sits at the top of the WHO's list of global health threats and it kills millions. But we're not talking just about the pollution in the street: the elephant in the room is pollution indoors, which - it turns out - kills just as many people as pollution exposure outside, yet gets only a fraction of the attention. England's Chief Medical Officer, Chris Whitty,  together with public health and atmospheric chemistry colleagues, wants to change that. They've laid out a plan for getting to get to grips with the unknowns around indoor air pollution. Ally Lewis is from the University of York…

Ally - Everybody pictures outdoors as the place that pollution exists. But actually around 3 to 4 million people per year die because of their exposure to indoor pollution. So it's a huge global health issue. Understandably, for a long time, perhaps 200 years, the focus of governments and industry was in cleaning up outdoor air. Outdoor air quality historically, in places like the UK, was really terrible. There have been huge improvements in outdoor air quality in the last 50 years and particularly so perhaps in the last 20. So although there's a long way still to go with outdoor air, we have to look about whether we can get some equal or perhaps even greater health benefits by cleaning up indoors. So the focus on indoor air now is partly because of the success we've had in cleaning up outdoor air.

Chris - You've written this opinion piece this week with a number of other authors, one of them, the chief medical officer, Chris Whitty. You've set out five areas that you think warrant particular focus. I'll just put those to you and perhaps you could comment on why you've chosen those particular areas. You've led with 'Understand what's harmful.'

Ally - If we are going to introduce interventions or introduce policy or introduce technical fixes, we want be sure that we're dealing with the most harmful components of the air that we breathe indoors. And this is still an area of uncertainty. Chemical emissions from burning the solvents that we use from even things like cooking, there's also a lot of biological material indoors, so spores and moulds and respiratory viruses that we exhale. So before we design our solution to the problem, it would be really good to understand which of those targets is the one that's likely to give us the most benefits.

Chris - And I suppose that leads on to your second point, which is that you want to model how pollutants form and how they accumulate.

Ally - Indoor air is different to outdoors. The biggest difference being that it sees a lot less sunlight and, in outdoor air, sunlight drives a lot of the chemistry that transforms pollutants. This is something that we have to be able to simulate properly because when pollution is released indoors, we've got to be able to follow it through its full life cycle. And this ability to predict what happens to pollution indoors is much less advanced than we have for outdoor pollution.

Chris - The issue you're grappling with though, and I think this is really what you point to in your third point, which is 'explore the effects of local variations.' No two buildings, at least in the UK, are the same. And they're all different ages, different designs, different structures, different furnishings, different people, different people densities. All these things mean there must be so many degrees of freedom. How can you do this meaningfully?

Ally - It's incredibly varied indoors and it's much harder to predict than air pollution in outdoor spaces. But we think that there are some prospects to make really good progress. So one area that we would like to see advances in is the estimation of emissions. So outdoors, we know very precisely, for example, how much emissions come from the back of the diesel car driving down the street. We'd like to get those same sorts of estimates for emissions that occur in indoor spaces, for example, from a wood burning stove or a gas cooker. The next step would be to understand a little bit more about the ventilation rates in homes. And then finally we'd like to know where the pollution ends up - what is its ultimate faith.

Chris - It's interesting you bring up the point about accumulation indoors because I've watched quite a few episodes of grand designs now (which I like very much by the way) people seem to be striving for building homes that are almost hermetically sealed. They pride themselves on having a poorly ventilated home to make them extremely energy efficient. But are we not in danger therefore of trading an energy cost for a health cost? Because basically when you live in an ancient property like I do and it costs a fortune, but you know it's well ventilated because there's more holes than walls. With these modern buildings, we're sort of trapping the air into a sort of chemical stew pot that we sit in the midst of, aren't we?

Ally - There is certainly a risk that as we improve energy efficiency in homes, for very good reasons, it reduces greenhouse gas emissions, it reduces costs but we do end up leading to indoor environments where air becomes more and more polluted. We accumulate more and more chemicals indoors and we have to address that. And there are technical fixes to this. It is possible to retain the heat that still allows fresh air to enter, but there is a certain amount of trade off here between energy efficiency and indoor air quality.

Chris - And you also propose that we need to understand the best ways to improve indoor air quality. What sorts of things should be at the top of the list?

Ally - In a place like the UK, if it's wet and windy, certainly the best way to improve air quality is simply to open the window a crack and improve the ventilation rate. But that might not be the best advice in the middle of summer, in the middle of heat waves when things like photochemical ozone begin to accumulate. So the advice that we provide is going to have to be dependent on the location. It may be different depending on the meteorological conditions. And finally it might actually be different depending on where your house or your school or your business is. You know, those in rural environments generally can use outdoor air to clean up while those that are right by busy roads might have to take different approaches.

Chris - And lastly, you say you want to bolster the evidence base, strengthen the science. What do you really want to know?

Ally - At the moment, it's quite difficult to provide advice to decision makers or to building owners over which actions they might take that would have the largest beneficial effect. And quite understandably, people are reluctant to take action, to invest money, to use up capital. It's trying to persuade people to live differently, giving them the confidence that they're being provided the best possible advice or they're tackling the sources that are going to lead to the largest health benefits if we make changes. So this is where we need to bring more scientific evidence into the debate to give confidence to people who may have to make decisions or provide us with the nudges that we need to improve indoor air.

Hot air balloon

20:29 - Balloons supporting scientific study

The long love affair between scientists and balloons dating back to the 18th century...

Balloons supporting scientific study

Thanks Chris. Calling in from 2000 feet here. Well, not really.

I’m sure you’ll have heard, this week, of the Chinese surveillance balloon that the US shot down which they now claim was able to collect communications signals. Equipped with instruments capable of "intelligence collection operations" it’s sparked a major international row.

In the face of US accusations, the Chinese government is sticking to its story describing the vessel as ‘a scientific research balloon.’

So what’s the precedent for using balloons for scientific research?

Well, as it happens, even in an era when spaceflight and exploration missions are almost routine, balloons continue to offer a key research tool for astronomers, astrophysicists and atmospheric scientists.

For all this to be possible, the idea for the first flying balloon was conceived by Jacques Charles who helped the Robert brothers build the first hydrogen balloon in 1783.

More people perhaps will know the Montgolfier Brothers, though, as the architects of the first manned hot air balloon flights in France in 1783. Ballooning for the early pioneers that the brothers inspired, however, was something of an entertainment industry: a  competition between the most skilled engineers, battling to see who could go highest to draw in the largest paying crowd. Jean Pierre Blanchard, one such early professional pilot, is remembered for being the first to cross the English channel by balloon in 1785.

This history of ballooning daredevilry culminates in Felix Baumgartner’s skydive from a helium balloon in 2012 at an altitude of 39km, reaching a top speed of 1358 km/h and becoming the first man to break the sound barrier without vehicular power.

Balloons taking scientific measurements can be traced back again to France, and meteoroligist Leon Teissernec de Bort. From 1896, he launched hundreds of balloons from his observatory, noticing that air temperature got lower and lower up to 11 km in altitude, but a constant temperature above that height. This led to the discovery that the atmosphere was split into two layers: the troposphere below and the stratosphere on top.

Modern weather balloons carry instruments to measure atmospheric pressure, temperature, humidity, and wind speed. Weather balloons are launched globally for current conditions and weather forecasting by both human forecasters and computer models. They are released routinely from 900 to 1,300 locations around the world, two to four times a day.

Meanwhile, NASA use multiple types of balloons to lift scientific payloads into the atmosphere as a low cost way to take measurements over long durations, equipped with radio receivers and powered by solar energy.

So while the rich history of ballooning does feature a strong scientific heritage, you can see why the multiple antenna US officials say they found attached to the suspected Chinese surveillance balloon has raised a few eyebrows.

Diagram of a stomach

23:52 - Stomach ulcer drugs boost TB treatment effect

Common drugs used to treat ulcers can reduce treatment time for TB sufferers

Stomach ulcer drugs boost TB treatment effect
Lalli Ramakrishnan, University of Cambridge

The bacterial infection tuberculosis - TB - is one of the world's deadliest diseases: around 10 million people per year fall ill with it, and in 2021 it killed one and a half million. The infection is notoriously hard to treat because not only is it mutating to become resistant to our antibiotics, but also because patients need to take medication of many months to effect a cure. As well as beign costly, this can lead to poor adherence and relapses. But not researchers at the University of Cambridge may have found a way to dramatically shorten treatment times: by simultaneously administering a common class of drug used to treat excess stomach acid and ulcers, as Lalli Ramakrishnan explains...

Lalli - The thing that we've discovered is that the TB bacteria have these pumps. They literally can pump out drugs that are administered to them, and they turn on these pumps when they're inside of us. And what we found is that many drugs have incidental activity against these pumps. And then when we screened these, uh, so-called proton pump inhibitors,

Chris - These are the ulcer drugs.

Lalli - The ulcer drugs had very good activity against the bacterial pumps. And so we went ahead and tested them in a lab-based experiment to see if they could reduce the time to treatment just in a. It's a strictly lab-based experiment, but it gives us a clue that we should go forward with these and move on to, say, animal models and people.

Chris - So in summary, then the microbe is cunning and it produces this pump, which it can turn on, which when you throw drugs at it, it can immediately chuck them. It's a bit like me seeing a hand grenade come through the window. So I quickly pick it up and lob it out again before it goes off <laugh> and saving my life in the process. And you have found a way of basically locking the window so it can't throw the hand grenade back out, and therefore the drug does detonate inside the cell. And it just so happens that proton pump inhibitors, things like omeprazole that we give for the stomach, happen to have as one of its side effects, this effect on these bacteria.

Lalli - Correct. It basically can clog up that pump, literally just clog it.

Chris - Will this work for other infections? Because there are other hard to treat infections where there's probably a similar sort of thing going on where it's hard to get the drug into the bug for long enough and it makes it hard to treat, it makes it expensive to treat. Could we try your trick elsewhere beyond just tb?

Lalli - Yeah. In fact, all bacteria have these pumps and the bacteria that we are particularly interested in is a bacterium that's quite related to TB. It's called Mycobacterium abscessus, which causes really bad disease in many parts of the world, including here. For example, you know, there've been a series of infections and even deaths and we would very much like to try that as our next goal to see if these pump inhibitors work, because those are even more recall to infection by far than TB.

Chris - But obviously you are doing this in a test tube at the moment. There must come a point where you're going to say, well, we now need to do the clinical trial. And presumably you could do that by, can you not look at the patient records and see some people who've been on treatment and had these drugs incidentally and find people who've got better quicker?

Lalli - The problem with looking at these records is that in a place where there's a lot of TB records are not necessarily the best and there are lots of, you know, extraneous factors. So it's very difficult. One needs to do a prospective trial, which we very much hope will happen.


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