Lesson 4: the temperature of the Earth

temperature of the earth

In this lesson, we’re going to do what physicists like to do – we’re going to over-simplify the Earth and do a “thought experiment”.

So, we’re going to imagine that the Earth doesn’t have an atmosphere and we’ll work out what temperature it “should be”. This builds on the lesson on blackbodies.

First, the Sun is sending light towards the Earth. The Sun is very hot and emitting light in all directions, but the amount of energy coming directly towards the Earth (the solar irradiance) is 1360 W / m2 (ish – we’ll come back to how we measure this later). But that’s the light coming towards the Earth and, of course, half the Earth doesn’t get hit at any one moment (it’s the night time) and towards the poles, that 1360 W gets spread over a much bigger area of Earth.

To understand that consider 1 square metre rings in a row in front of the Earth (top picture): over the equator the light going through those rings forms a circle on the Earth; but over the poles, it would be spread over a much bigger ellipse. So – the average power falling on a square metre of Earth’s surface at any one time (averaged over the whole Earth) is about 1360 / 4 = 340 W / m2 (watts per square metre). That’s like having 4-old fashioned lightbulbs on every square metre of the Earth.

Now, the Earth can’t get hotter and hotter and hotter! It will reach an “equilibrium” where the heat in equals the heat out. (Equilibria are very common in physics). The way it releases energy into space is via its own blackbody radiation. You may remember from our lesson on blackbodies that everything that is hotter than absolute zero radiates energy with a blackbody curve. And that is true of the Earth too. As the temperature of the Earth is quite low (compared to the Sun!), it will radiate most of its blackbody radiation in what we call the “thermal infrared” (long wavelengths).

We can work out the total power of the blackbody by working out the area underneath that curve. There’s a simple calculation there. The total power of a blackbody in a square metre of its surface emitted into space is sigma times Temperature to the power 4. (σT4. Sigma (σ) is the Stefan-Boltzmann constant and is 5.670 367 × 10-8 W m-2 K-4 .

If the Earth were perfectly black at both short wavelengths (visible, near infrared – the wavelengths the Sun emits) and at long wavelengths (thermal infrared – wavelengths the Earth emits), then we could write:

Incoming power in a square metre = outgoing power in a square metre

340 = σ × T4

So the temperature = 278 K = 5 ºC.

(To do this calculation yourself, remember that the Stefan-Boltzmann constant can be written with the decimal place moved 8 places, so 0.000 000 056 704 and to get from Temperature to the power 4 is something to Temperature is something you can press the square root button twice)

If, as is more realistic, the Earth has an average reflectance in the visible of 30% (so it reflects about 30% of the light from the sun straight back to space and absorbs 70%) but it is still perfectly black in the thermal infrared (not unreasonable), then

Incoming power in a square metre = outgoing power in a square metre

70% × 340 = σ × T4

So Temperature = 254 K = -18 ºC

Now, we have made A LOT of approximations here. The actual average reflectance of the Earth might not be quite 30%, and it’s not quite perfectly black in the thermal infrared – but the basic picture holds. If the Earth had no atmosphere at all, the average temperature across the whole world would be something close to -15 ºC to -18 ºC.

And just in case you think I’ve pulled the wool over your eyes, I thought I’d find out the average temperature of the moon – after all, it’s about the same distance from the sun as us and it’s about the same sort of reflectance. So I searched the internet for “average temperature of the moon” and found an answer here: https://socratic.org/questions/what-is-the-average-surface-temperature-of-the-earth-s-moon

I was most amused that it said:

“You could take an average of the mean maxima and minima to get a mean surface temperature of -23 °C, but it wouldn’t be very meaningful.”

I beg to differ – that is very meaningful – as it’s very close to what I calculated with my overly simplistic thought experiment. (The moon reflectance is a bit different and it’s fraction pointing towards the sun is perhaps a bit different and the average temperature is not necessarily the average of the minimum and maximum temperatures)

Of course, the reason that the average temperature of the Earth is not that cold – and is nearly 35 ºC hotter – is that we do have an atmosphere. But you might be surprised to know that if our atmosphere was 100% oxygen, nitrogen and argon (and not 99.9 % oxygen, nitrogen and argon) it would still be -18 ºC. I’ll explain why in the next lesson.

 

Lesson 3b: More on the solar spectrum lines

Source: N.A.Sharp, NOAO/NSO/Kitt Peak FTS/AURA/NSF
Published: November 30, 2017

390_highresolutionsolarspectrum1200w

I was asked:

‘In the sun’s spectrum there are black lines at special wavelengths’
This threw me a bit, and so in the continuing paragraph I also got confused. The ‘spectrum’ is the range of light yes? I’m not sure why there are black lines in there. And so then are these black lines acting as blackbody? Are the black lines matter? or more electromagnetic waves?

So let me explore that a little more.

The spectrum is the rainbow – but extending beyond the visible. It’s the light spread out in different wavelengths. Above is the photo NASA took of the spectrum from the top of a mountain in Arizona, USA. Note that really it’s one line going from red to blue, (it’s not 2D – they just made it that way to fit on a page!). The colour you see is the spectrum from about 800 nm (top left) to about 400 nm (bottom right) – the visible part of the solar spectrum. (Note that the solar spectrum actually goes from about 200 nm in the UV to about 3000 nm in the infrared – but we can only see this little bit of it).

You also see black lines in the spectrum. These come from gases either in the outer part of the sun or in our own atmosphere that absorb light with particular wavelengths because that light has exactly the right energy (E = h nu) to make an electron jump from one orbit to another. Later the atom might release that energy going back down again – but, this is the crucial bit, it won’t do so in the same direction that the light was going in in the first place (and sometimes that will then cause another atom’s electron to jump up). So less light gets to us at those wavelengths than should – and we see black lines in our spectrum.

Lesson 3: My favourite equation

E=hnu picture

When I was 17 and doing A’level chemistry I learnt the equation E = h nu. This was the most exciting science lesson of my life. Seriously. I was only disappointed that chemistry rather than physics gave me that gift 😂

You see, I’ve always been fascinated by colour – the mixture of a prism for my tenth birthday and my dad being colourblind (a condition one of my two sons has inherited from the x-chromosome I got from my dad: the other son got the x-chromosome I got from my mum) meant that I really wanted to understand how “colour worked”. Now there are three bits to that – understanding our eyes (a detour I won’t go down now), understanding blackbodies – which explains white light – where lots of wavelengths are present, which we covered before, and understanding E = h nu which explains lights being coloured in and of themselves.

What this equation shows is how atoms interact with light. You’ll remember the simplified model of an atom with a central core and electrons in rings around it? Well, when an atom is “excited” the electrons can go up to a higher orbital. And when they fall back down to the ground state (the state where all the electrons are as close to the nucleus as possible while obeying the rules of how many electrons can be in each orbital) they release energy (based on the size of the jump) as light and the frequency of the light (nu) is proportional to the energy jump. So the bigger the energy of the jump, the higher the frequency of the light (more blue, less red).

You can see this yourself. Drop salt into a flame and the heat of the flame will excite the sodium atoms in salt to a higher energy state. As they fall back down they release yellow light. You might recognise that yellow light if you remember sodium street lights. In those electricity excited the sodium atoms. (Go on, try it!)

In the sun’s spectrum there are black lines at special wavelengths (called Fraunhofer lines). That is this process in reverse. The outer part of the sun is cooler than the inner part and absorbs light to make electrons jump up to higher orbitals. So the blackbody light from inside the sun (all wavelengths) loses light at the special E = h nu wavelengths. Of course those do re-emit those wavelengths as they drop back down, but here’s the crux: they re-emit in all directions including back towards the middle, so the amount of light coming towards us is lower.

This is how helium was discovered – they could match most Fraunhofer lines to lines they could get by putting elements into flames – but there were a set of lines they couldn’t match, so they proposed a new element – helium. (From Helios). Later they found helium on Earth. This is also how neon lights work – different jumps in neon give the different colours of neon light.

Now atomic lines are high energy so they tend to be in visible spectral bands. Later we’ll see that molecules have absorption/emission lines too. These are not from electrons jumping but from the molecule wobbling. Because whole atoms have to move the energy is much lower (heavier things don’t move as easily). So these lines are in the infrared.

But we’ll come back to that.

Lesson 2: Blackbody radiation

blackbody radiation

One of the most important bits of physics to understand, before we get to climate, is what blackbody radiation is all about. So this builds on lesson 1 about the electromagnetic spectrum. Here I’ve zoomed in on the middle bit and turned the scale around (so now IR – long wavelengths – are on the right and UV – short wavelengths – are on the left).

When something is perfectly black, it will absorb all energy falling on it (nothing is reflected) but if that were the whole story, things would get hotter and hotter for ever. Of course, that does not happen – because black bodies also radiate energy away as “light”. The blackbody curve (see picture) shows how black objects radiate “light” – and what wavelengths of electromagnetic radiation are radiated. That depends on how hot the object is.  Max Planck wrote down the theory of the blackbody curve back in 1900 and, almost by accident, invented quantum mechanics in the process (but let’s not get side tracked down that interesting alleyway).

As a blackbody gets hotter it emits more light and the spectrum shifts “up and left” (so more light, and the peak moves to shorter wavelengths).

Now that’s all a bit physicy and esoteric so let me link it to things you already know. You already know the idea of “red hot” – as you start heating an electric stove and it gets hotter there comes a point where it starts to glow red. What has happened is that the curve has shifted up and left enough that there’s enough red for you to see it. That’s somewhere around 600 degC (scientists call this ~900 kelvin as we like to start temperatures at absolute zero).

If you keep heating something up it will go orange hot as you start getting orange and red wavelengths too. Your old fashioned tungsten lightbulb (I hope by now replaced by an LED!) had a tungsten filament at around 2500 K – 3000 K (subtract 273.15 to convert to degrees Celsius). That was a yellowy-white. The outside of the sun is about 5500 K and that is “white hot” – the peak of the blackbody curve is in the middle of the visible so all the wavelengths are there and they mix to look “white” (remember Newton splitting white light with a prism to show all the wavelengths are there). There are stars hotter than our sun that are “blue hot” as their peak is in the UV and their spectrum is already dropping in the visible – with blue much higher than red.

But you can see from the graph that the sun also emits plenty of what we call “short wave infrared” (incidentally that was the problem with tungsten lamps – almost all their radiation was actually infrared and thus invisible.).

Of course it doesn’t stop there. Almost everything has a blackbody curve. Blackbodies around room temperature (~300 K) have a peak at wavelengths around 10 micrometres. That’s a wavelength we call “the thermal infrared” and it’s what those thermal imaging cameras you see in science museums (the ones that give people red faces and blue noses and black glasses) measure. Even space itself has a microwave blackbody signal – that represents a temperature of around 3 K (just above absolute zero) – and is the temperature the Big Bang has cooled down to.

Now real objects aren’t perfect blackbodies – they reflect some light – but these basic ideas hold up. And the sun and earth are, to a first approximation, blackbodies at 6000 K and 300 K respectively. And this matters because it’s how the sun heats the Earth up and how the Earth cools back down again.

(Don’t worry, we’ll start getting onto the climate soon! This is the background stuff that makes the explanation meaningful. I know this stuff is hard, so please feel free to ask questions. Lesson three will involve my favourite equation and how atoms and molecules emit and absorb single wavelengths of light rather than blackbodies emitting and absorbing broad spectra … and then we’ll start talking about the temperature of the Earth!).

Lesson 1: Electromagnetic Radiation

EM Spectrum image

To understand climate change, we first need to understand light. (Personal aside: I got a prism for my tenth birthday and told everyone that one day I’d get a job splitting light into pretty colours – so of course I start here)

Light is electromagnetic waves that travel at the “speed of light”. The properties of light depend on the wavelength (how many times the electromagnetic field vibrates). Short wavelength light vibrates lots and the wavelength is small enough to get inside you and damage you – that’s “ionising radiation”: ultraviolet that damages your skin and x-rays and gamma rays that go inside.

Long wavelength light is radio and microwaves and the infrared. That can’t damage your molecules directly, but (and we’ll come back to this), some infrared and microwaves can make molecules vibrate which heats things up.

In the middle is visible light – the bit we can see. At 400 nm (nanometre – that means 0.000 000 400 m) wavelength we start to see blue light (if we don’t have cataracts) around 555 nm it looks quite green – and our eyes are most sensitive. At 800 nm we just about see a deep red (unless colour-blind and lacking red sensors).

Now it’s no coincidence that this is the bit of the electromagnetic spectrum that we see best. This is the peak of the sun’s spectrum – and all we see on Earth is visible electromagnetic radiation from the sun (or one of our artificial lights) that reflects from the Earth.

But the Earth itself does glow – just in wavelengths we don’t see. We call that the thermal infrared. In lesson two I’ll explain about blackbody radiation.

Climate Lessons Introduction

This is my personal blog. I’ve been using it for a few years to post my thoughts. At first it was a place where I explored my thoughts about topics that were controversial – particularly those that people argued about on Facebook. I also explored my faith and how I connected my science to my faith.

However, recently, I started writing “lessons on climate change” on Facebook. I did so because I wanted to help my friends understand some of the basic principles of climate science. I soon realised Facebook was not the best place for such lessons, so I moved them here. Because the blog still has some more personal posts, I’ve left this anonymous. I may change that later – but I’m guessing most of my readers know exactly who I am.

I’ve now posted quite a few climate blogs – so I’ve created a page to help you find them easily.

Resonance

This is something I wrote some time ago that describes why I use the analogy of resonance to explain what I feel in my faith when I am aware of God. 

Part 1: Physics
In physics the term resonance refers to the phenomenon where a free body will vibrate in response to an external frequency. It is what causes a hanging bell to start to ring if you sing its note – and it’s what causes a wine glass to crack to a soprano’s singing. The resonance of atoms in a laser gets light to be emitted in sync, in phase – so the laser beam is amplified and coherent. A swinging pendulum in resonance with a vibration will start to swing every larger swings.
In all these examples the body in resonance simply responds. And when it is in full resonance it has energy far bigger than it had in isolation – the pendulum swing grows, the grass cracks, the bell rings loudly.
A body can be in partial resonance too – when its frequency (note) doesn’t quite match the forcing tune. If the body is free it can come into resonance – the pendulum swing will change to match.

A body can’t be in resonance if it is touching others – glasses pushed against each other will hit each other and sound “clashing” rather than ringing a note. Atoms in a lightbulb filament emit white light (mixed “clashing” frequencies) rather than the pure colour of a laser beam.
Part 2: Explaining the analogy

An analogy that means a lot to me is the analogy that “walking in the Light” means a heart, mind and soul in resonance with God. When we are in full resonance, we respond to God. We are “in tune” with God, we are in sync with God.

In this state our response is natural, we actually can’t help obeying God – God’s Will becomes our only option. The things we struggle with when we are out of resonance: “how do I be still?” “How do I find God?” “How do I know what is God’s Will and what are my own notions?” These questions – once so urgent – become irrelevant as the answer is obvious.

“How do I resist temptation?” is no longer a question of will power, because there is no will power. We simply respond the only way a body in resonance can – we sing God’s tune.
We don’t fall immediately into resonance – we approach it, our swing gets closer to God’s. As we approach resonance we start to feel it, to sense ourselves going into the flow of Life Abundant. Our sense of strength, our ability to act, our ability to love grows – and the more we let go into resonance, the stronger the power of God acts through us – we feel that power, that energy, that overwhelming outpouring of Love. 

It is not the frenetic energy of our own adrenalin rush, it is a calm energy – an energy where time, our physical health or our limited skills don’t matter because it is not us who is acting, but God acting through us. God directs us, draws us closer.

In full resonance we cannot easily be knocked by the outside world. Our hearing of God’s tune is so much stronger than what the world throws at us.

We can, however, lose resonance. And the physics analogy works here too – we lose resonance if we become stiff (or too floppy) – if we don’t let go into the song, (or lose our integrity and wholeness). If we resist God’s tune, the resonance is dampened and we do feel that dampening – we lose the energy we had, we lose the sense of easy connection, we start to ask the questions again: how do I find God? How do I know what is of God and what is of me? How do I hear God’s Will? 

Sometimes the loss of resonance is internal – our own stiffening; sometimes it is external. Like the glasses pushed together, we can no longer sing our tune with God because we are jostled, hit into by other people’s agendas, constrained by worldly commitments. We may be knocked out of resonance by an external blow or simply slip away because we let our attention drift away.

To get back into resonance we simply need to hear the Song. We need to let go and be vulnerable and weak so we are free to move in response, not stiff from our own notions. We need to separate ourselves – slightly – from the people who stop us responding, a separation that also leaves them to respond themselves. In physics, “loosely coupled oscillators” get into sync with each other and the main beat naturally – we need some connection with other people, but not so much that we are dependent on them.

Finally, we can consider a gathered Friends’ Meeting for Worship as one in which everyone has reached resonance with God, the driving force. That resonance naturally means that we also reach resonance with one another and that energy (here – Love) flows between the different people so that we remain individual, but respond together. 

I feel spiritual resonance with God physically and in a gathered Meeting for Worship I can feel the flow of Love between people. 

Martha and Mary

“As Jesus and his disciples were on their way, he came to a village where a woman named Martha opened her home to him. She had a sister called Mary, who sat at the Lord’s feet listening to what he said. But Martha was distracted by all the preparations that had to be made. She came to him and asked, ‘Lord, don’t you care that my sister has left me to do the work by myself? Tell her to help me!’ ‘Martha, Martha,’ the Lord answered, ‘you are worried and upset about many things, but few things are needed – or indeed only one. Mary has chosen what is better, and it will not be taken away from her.’”

Luke‬ ‭10:38-42‬ ‭NIVUK‬‬

For centuries this story has been read as two women quarrelling over the housework or food preparation. And it rather puts women in a no-win situation: it comes out clearly that Mary is better for sitting and listening and yet every woman knows the housework still needs doing, especially when visitors come round. 

I was thinking of this when I was watching someone’s post on Facebook of a video of a rather smug mother showing off about what a better mother she was than other people. She was talking about how she was bringing up her children to be respectful while other mothers clearly didn’t care. And realising full well the irony of telling myself a story about her to understand why she was telling herself stories about others, I couldn’t help noticing her expensive sports clothes, immaculate kitchen and other things that suggested she was rich, not working in a paid job and privileged. And I thought that she probably had no idea what the lives of the women she was criticising were like. We women can be really horrid and judgemental to each other. As in my post on defensiveness, I wonder whether this judgemental accusation is hiding our own weak ego, needing the reassurance that we aren’t wrong. 

So back to the Martha and Mary story, which for so long has frustrated me because it made me feel guilty about being so overwhelmed with my busyness that I don’t make time to sit still. I felt doubly got at: first I do more than my share of work and then I’m told that I’m wrong to do so! (See how I’d personalised it?!) The story pits the two sisters against each other and doubly seems to punish the hardworking one who is already exhausted. 

So I was fascinated to read a book by Mary Stromer Hanson which told the story differently. She pointed out that the King James translation has an extra word “also” in verse 39:

“And she had a sister called Mary, which also sat at Jesus’ feet, and heard his word.” KJV Luke 10:39.

This goes back to the Greek but has been missed out in modern translations. The implication is that both Mary and Martha “sat at Jesus’s feet” (which is likely to be an idiomatic phrase describing their roles as his disciples – and therefore, as an aside, taking on a role that was clearly not just for men).

It goes on:

“But Martha was cumbered about much serving, and came to him, and said, Lord, dost thou not care that my sister hath left me to serve alone? bid her therefore that she help me.” ‭‭Luke‬ ‭10:40‬ ‭KJV‬‬

There is no indication here that the “serving” is in the kitchen. It could equally be some other type of service, perhaps in a community, or even “ministry”. 

Jesus answers, and we have always read this as a rebuke, but try reading it again in a comforting voice, reassuring her that he has heard her worries and sympathises, but wants to remind her that the type of service Mary is doing (one which has led her to leave home and Martha, perhaps?), is good for Mary. 

“And Jesus answered and said unto her, Martha, Martha, thou art careful and troubled about many things: But one thing is needful: and Mary hath chosen that good part, which shall not be taken away from her.”

‭‭Luke‬ ‭10:41-42‬ ‭KJV‬‬

Now, is this new reading more “right”? I don’t know, and from how I interpret spiritual truth (see earlier blogs on religious Truth), it doesn’t matter too much [any atheist reading this far who thinks this shows how you can read anything into the Bible and therefore it’s meaningless is missing my point as much as any Bible-literalist who thinks I’m wrong because I’ve looked at it differently from how they were taught…]  The point is, that how we read Jesus’s reply depends a lot on the story we’ve told ourselves about who Mary and Martha are. 

And maybe how we read other people’s parenting stories on Facebook depends a lot on the stories we tell ourselves about them. 

So let’s return to what Jesus might be saying here: Mary’s way (the type of work she does) is good (for her). You have your own burdens, Martha, and I sympathise, but you don’t solve those by stopping her following her path. 

So, whether we are mums or not, whether we work outside the home or with our families, whatever we do, let us not attack each other!

But one final contradictory word (because I like living on the contradictory edge) – when I do stop my busyness and just sit, I always benefit and know it is good. 

Defensiveness

“Why are the youth of today so defensive?” Someone asked me this question this week and although it was rhetorical, I’ve been pondering it. I’ve struggled with some hot tempers at work this week too – people stressed before a deadline getting wound up with each other. I’ve felt those emotions too and noticed my own defensiveness. 

As part of my study of conflict I want to explore this question. Defensiveness is a response to perceived or real threat and often causes statements that threatens others, making them in turn defensive. I’ll split the question into three parts: why are people defensive? Why are youths defensive? And are the youth of today more defensive?

Why are people defensive?

The first reason for defensiveness is attribution bias, our tendency to explain away our own mistakes as caused by external and temporary factors (a bad day, someone’s interference) and to blame other people’s mistakes on their character (being insensitive, being lazy). We often tell ourselves stories about other people and their motivations for a certain behaviour: “he’s selfish and uncaring and didn’t acknowledge my work in the meeting because he doesn’t value me” and tell ourselves stories that are more flattering version “she’s so overreacting (typical!). I’ve had a tough week and put that presentation together in a rush, I just made a mistake, why is she so sensitive?!” Before long we talk to these pictures of each other that are in our heads and get angry that the other person’s picture of us is so wrong without recognising that so is our picture of them (from their perspective). The “unfair” attack on us makes us defensive. Their defensiveness makes us frustrated and unfairly criticised for our criticism. 

An outsider can often see the stupid pettiness of these arguments. The people involved are too blinded by emotion and their pictures of each other to see that pettiness. 

To reduce our own and other people’s defensiveness we need to change our pictures of each other. We need to be curious rather than jumping to conclusions. In their book series “Crucial conversations” and “crucial accountability” the Vitalsmarts team encourage you to go into a conversation that could be emotional having prepared by thinking “why might a well meaning, intelligent and considerate person have done that?”  The aim is to answer that in multiple ways, to realise that we are telling ourselves a story about the other person which may not be the only explanation of the facts. 

Why are youths defensive?

Attribution bias is one contributing factor of defensiveness, but it is not the only one. The other main factor is a sensitive ego. There are, I think, three stages in the development of the ego: in the first stage we build the ego up – we build up our sense of self. At this stage our ego is very vulnerable and easily slighted by other people’s comments. We may be boastful or showing off, we care deeply about what other people think of us (even if we try to kid ourselves we don’t!) and we are easily hurt. At this stage we are often defensive in an emotional way. 

In the second stage we have a strong ego and have built a lot of confidence. People in this stage are often “thicker skinned” than those in the first stage: They are less likely to be defensive and hurt by other people’s feelings about them, but also less sensitive to other people’s ego needs. There is often a sense of having achieved a maturity: emotionally and in terms of professional skills and with this a willingness to judge as inferior those who haven’t achieved that. 

There is a third stage, one that Richard Rohr describes eloquently in his book “Falling Upward“, in which we consciously and freely let go of our ego needs, in which we choose to accept criticism not in stoic martyrdom or with bitten-tongue resentment, but in Love. In this stage we can even accept that we don’t have to like ourselves: we accept our flaws simply, patiently and as God does. 

Richard Rohr describes two parts to our lives, one in which we build up our fragile egos and a second part where we let go of our strong one. My experience is that it is more circular than that. As I let go of an old model of myself, a new one arises that is initially vulnerable. In its early vulnerability I am easily hurt and very defensive. Eventually I become more confident and the defensiveness diminishes, but my judgements of other people increases. At some point I realise I can let go that label, that need to be right, and as I do so I accept both myself and others. That opens my eyes to a deeper truth, and being human, I personalise that truth in a new model of myself and the cycle repeats. My moments in the third stage are fleeting and all too temporary, but they are also sufficiently real for me to know they are true. 

(If that was all too spiritual, I also have a more prosaic model – I started as a physicist and initially went through a defensive stage about my physics ability, then I got more confident (less defensive but more arrogant), and eventually sufficiently confident not to worry about criticisms, at which point I was promoted into management and I went through a defensive stage about my management ability and the cycle repeated until I let go of needing to be right, at which point I was promoted to being a leader…)

Despite this circle, there is a component of age. The young have been through this cycle less often and less consciously than the old. It is probably not just the youth of today who are extremely defensive, but the youth of any age. 

Why are people today more sensitive?

I started this blog with the question I was asked rhetorically about why the youth of today are so defensive. I’ve suggested so far that it is a combination of attribution bias making anyone defensive and the specific ego needs of the young making youths defensive. 

And yet, the questioner had also noticed something about today. We see a lot of open defensiveness. Part of this is our new medium of communication: the comments threads on Facebook or newspaper articles do not bring out the best in people and so many of us spend hours every day reading them. Does that tone spill into our more human interactions too?

But my observation of the defensiveness at work this week (including my own) showed another modern malaise: stress. Far too many of us are overwhelmed by busyness, by a continuous stream of things to do, by information overload, by overflowing email inboxes. We are all running at the edge of our ability to cope and it takes only the slightest trigger for that stress to flip over the edge to the point where it comes out in our interactions with other people. Maybe we are more defensive nowadays because it is a stress response. 

So, to conclude, if we want to break down conflicts caused by defensiveness we need to acknowledge the stories we are telling ourselves that make us purer and them nastier than we really are. We need to build a strong enough ego and then freely release it. We need to insulate ourselves from the aggressive patterns of Internet comments threads, probably by limiting our time on them and we need to let go of our busyness and stress. 

None of those steps is easy. We will all stumble at some point in that. So we should also learn to forgive ourselves and each other for the defensiveness that remains. 

Not trusting experts

Probably the defining quote of the Brexit campaign was when Michael Gove said “Britain has had enough of experts.” That sentence either swung the poll in itself or was an incredibly astute observation from someone whose political reputation at that point was disastrous. It showed up the main difference between how Remain campaigned and how Leave campaigned. 

The university-educated middle classes, especially those in the “London-bubble” and who tended to vote Remain and made up the majority of the Remain campaigners, were using the kinds of arguments that convinced them: apparently rational arguments based on the views of economic (and other) experts. The campaigners spoke to different expert groups in turn and produced clear predictions of the difficulties: economic, legal, practical. The people who listened were themselves experts and they were convinced by other experts. 

The Leave campaign focused on more emotional arguments – appealing to national pride, fear of immigrants, the desire to “take back control”. It’s becoming increasingly clear that they didn’t have thought-through expert plans on what these ideas mean. 

Now, while I was (and am) staunchly pro-EU, the point of this blog is not to discuss those arguments. It is to consider why “Britain has had enough of experts” was so successful.

I think there are two reasons. The first is a sense of anger from a large part of the community who feels unheard, ignored and arrogantly patronised by the “elites”.  There is an isolation between London and the regions, between the wealthy and the poor. And this isolation has increased over recent years and while neither side really understands the lifestyle, challenges and pressures of the other, the power balance is very uneven. 

During the Brexit campaigning I joined a group on Facebook called “Scientists for the EU”. When anyone came on that forum and said anything pro Leave, the response (early on – the moderators stopped this eventually) was a barrage of insults about their lack of education, which amounted to “your opinion is worthless if you don’t have a PhD”. The arrogance and rudeness was awful. It’s hardly surprising that people wanted to annoy people who had treated them with such disdain by doing the opposite of what they said. 

That alone couldn’t fully explain the success of the slogan, though. Recently I understood a bigger reason. I was debating climate change on Facebook and I asked someone why she didn’t trust experts. This was her reply:


Another person expanded on this. They have noticed that Al Gore, who in the USA at least is the face of saying climate change is real, is a politician whose political views they disagreed with, and who now owns shares in carbon trading companies, so he will make a personal fortune if carbon trading is fully introduced. 

And without having distinguished scientific truth from other types of truth (see earlier blogs), because they disagree with (and are suspicious of) his suggested solution to climate change, they also don’t trust him saying climate change is real.