Wednesday 1 February 2017

Climate Science or Political Fiction?

A local group who provide English-language tours of the castle invited me back to speak at their monthly get together on 23rd January. I've spoken to them a couple of times before about low energy building, and they seemed to like my last talk about reading, so I spent my credibility capital trying to communicate climate change. 

I started talking about what was true the year I was born, almost half a century ago. For example: 

  • The earth's population was 3.5 billion 
  • Yugoslavia, Czechoslovakia, East Germany, South Vietnam were countries 
  • Every Prime Minister had been a man
  • Life expectancy in the UK was 72 years
  • Homosexuality was a crime
  • Carrots helped you see in the dark
  • Saccharine and tobacco were good for you
  • There were 9 planets in the solar system and none outside 
All of these things are no longer true.

Going further back, there are many more things that used to be true:

  • The continents were fixed on the earth
  • Time was the same everywhere in the universe
  • The world was created around 7,000 years ago with animals and plants in their current form
  • The earth was the centre of the universe
  • The earth was flat

Nice image but actually just a dried out rice field after harvest
In the case of the last "fact" I asked how people knew it wasn't true. Someone said their elementary school teacher had told them, which I had to point out was not a very good reason for believing something, based on all the things I'd just shown them were no longer true a few years later. Someone else said that you could sea the curvature at sea, which is a good reason. I added my own proofs: first that I've seen the shape of the earth on the moon during a lunar eclipse. Also I had been around the world, and had to change the date on my watch when I crossed from Asia to America. 

So what, I asked, is science? A series of facts? People in white coats with difficult equations? Good questions? A model of the universe? A process for finding truth?

It's a little bit of everything, but most of all it is a model for understanding the universe. As an example I told them about Newton and Einstein. For Newton time was universal, space was flat and had 3 dimensions, and gravity attracted masses to each other. Einstein's universe was radically different: the speed of light was universal, space-time had 4 dimensions, space was shaped by mass, and time was changed by gravity and speed. 

Some eyes were starting to glaze over and I could see they were wondering what use relativity was. After all, Newton's science got us to the moon. Einstein explains Mercury's orbit, which was a little out of sync with Newton's predictions, and GPS uses Einstein.

GPS, Global Positioning System, uses triangulation by measuring the distance from three or four satellites using light rulers. As we know from Newton, the speed of light is constant, and it travels around 30 cm every nano second. So if you are listening to timed signals from a few satellites, and you can can time the difference between the arrival of those signals, then you can work out where you are. 

The problem is that clocks in the satellites are 20,000 km up and moving at 14,000 km/h. The lower gravity up there means that the clocks are running 45 microseconds per day fast, and the higher speed means the clocks are 7 microseconds per day slow. This doesn't sound very much, but when you think that a nano second—one thousands of a microsecond—is 30 cm, this would put the satellite's positions out by 10 km per day.

The lessons to learn so far, before we've even dipped our toes into global warming, are that science changes, and that pure science has practical uses. When Einstein was pondering the structure of the universe, he was not trying to help people find themselves on google maps, but that has been one result.

So are there any scientific facts? Short answer: No. There is just the best model we have. Ideas that nobody has proven wrong yet; ideas that are probably not wrong.

For example, you have a friend with a coin that seems to come up heads a lot. You'd like to see the coin, but your friend is reluctant to let you closely inspect it. You suspect it's a double headed coin. You can't be sure, so you have to observe him using it. If he flips it once and it comes up heads, this tells you very little. There's a fifty-fifty chance that a two sided coin would come up heads. Two heads in row has a one in four chance, which is still not particularly unusual. Even three heads in a row has a one in eight change of happening with a fair coin. The more heads you see the more likely it becomes that the coin is rigged. If you see a hundred heads in a row, the chance of the coin being fair falls to one in a billion trillion trillion trillion.

Back to Newton and Einstein, we've been flipping the coin a lot more than a hundred times and it has come up heads every time, so it is very unlikely that their science is wrong. And it's not so much that Einstein proved Newton wrong, it's more about limits to where their ideas work. Newton's laws are correct on earth and for most planets around the sun, and for most parts of the universe. Einstein's are more widely applicable but they do stop working when we get near to black holes, or when we start looking at the very small scale of quantum mechanics. 

Now that we've talked about what science is, we can look at some scientific questions:
Is the earth getting warmer?
Is the earth getting warmer because of human activity?
Is carbon dioxide causing the climate to change? 

I asked what my audience thought, and they all seemed convinced that the earth was getting warmer, with one or two people not convinced that it was because of CO2 and human activity. 

To bring the first question close to home, I talked about Lake Suwa, where priests have been recording the date of Omiwatari, a crack that appears across the lake as the freezing ice expands. Ignoring any irony that the phenomena is named after gods crossing the lake, this represents the oldest human record that can be related to temperature. Everyone around here knows that the lake has not been performing is trick recent, but looking at the numbers makes things clearer. The lake did not freeze nine times in the 15 years 1998-2014. In the previous 47 years it did not freeze eight times 1950-1997. Looking at the first 257 years of the data, there were only three times when it didn't freeze over (1443-1700).

So what? This is compelling stuff, but does it prove the earth is getting warmer? It proves that lake Suwa has not been freezing over, but this could be a local climate change, or could be caused by chemical changes in what has gone into the lake in industrial times. When you look at a similar study of river in Finland where the date of ice break up has been recorded there is another bit of evidence.

On my next Powerpoint slide I had a list of organisations who are recording weather and researching climate and have concluded it is getting warmer. Powerpoint crashed on my computer, and I had to reboot. I don't have a list of organisation who are recording weather and researching climate who say it is not getting warmer. I don't think there are any. 

So the ten hottest years on record have all been in the last twenty years, and nine of them in this century. Figures are just out for 2016, which broke the 2015 record, which in turn broke the 2014 record. This is the kind of thing we see in the Olympics, where everyone is trying to break records. So is someone trying to break the climate record? If weather was random, you would expect a roughly even chance of the temperature being above or below average. There is a one in eight chance that the temperature is above average for three years running. The chance of the weather being higher than every year on record is small, and the chance of this happening three years in a row is vanishingly tiny.

So we can't be sure that the world is getting warmer, but it is very very unlikely that it is following random patterns. Could there be any reason that it is getting warmer?





Quick Chemistry question: How much CO2 does 1 litre of oil make? (see bottom for the answer)

This is Watt's steam engine, invented around 1800. Coal was burned to make steam, which pushed and pulled a piston to power a pump. The pump got water out of the mine and allowed more coal to be dug out. More coal went into the furnace to make more steam, to pump out more water, to get out more steam. And so on, for a couple of hundred years. These engines started working on railways to take the coal further away, and to reach further to get out more coal. 

Coal was the first fossil fuel, followed by oil, then gas. People have been talking about phasing out dirty coal, but it has kept on growing. Now that China has stopped plans to build more coal power stations, the planet has hopefully reached the peak and will start using less and less coal, although the White House today hides a love of the black stuff! 

So what? We have an increasing global temperature, and an increasing level of carbon dioxide. Does that prove that we are causing the planet to get warmer? No! Correlation does not prove causality. We do have a mechanism though. 

In 1896 Svante Arrhenius proposed the greenhouse effect, observing that different molecules store heat in the atmosphere by absorbing low frequency radiation coming from the earth and instead of letting it all out into space, radiating some of it back to the earth. This phenomenon can be seen by comparing our planetary neighbours. Venus has a thick CO2-rich atmosphere, and temperatures around 460°C day and night everywhere from poles to tropics. Mars has a very thin atmosphere and in the summer gets up to a pleasant 20°C in the day time, and down to a less hospitable -70°C at night.

So we have strong evidence that the planet is warming. We have increasing levels of atmospheric CO2 that have come from human activity. Also we have a historic match between CO2 levels and global temperatures based on air trapped in Antarctic snow. We have a mechanism by which CO2 increases temperature. Does this prove that we are causing global warming? No, it does not, but it is the best explanation we have, and no scientists have disproved it. 

"It is difficult to get a man to understand something, when his salary depends on his not understanding it." 

(Upton Sinclair)

There are plenty of non-scientists who are disagreeing, and this is called climate science denial. There are five stages:
Stage 1: It's not happening
Stage 2: It is changing, but it's natural
Stage 3: We are causing it, but it's not a problem
Stage 4: It is a problem, but we can't solve it
Stage 5: It's too late!

What examples can we find:

Donald Trump on Twitter:
"The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive." (7 Nov 2012)

"The con artists changed the name from GLOBAL WARMING to CLIMATE CHANGE when GLOBAL WARMING was no longer working and credibility was lost!" (31 Dec 2013)
(In fact the change was encouraged by Republicans and explicitly suggested by a global warming skeptic who stated that "'climate change' is less frightening than 'global warming'" Luntz Research: environment)

"This very expensive GLOBAL WARMING bullshit has got to stop. Our planet is freezing, record low temps, and our GW scientists are stuck in ice" (2 Jan 2014)

"I want to use hair spray... So Obama's talking about all of this with the global warming and the—a lot of it's a hoax, it's a hoax. I mean, it's a money-making industry, okay? It's a hoax, a lot of it." (December 30, 2015)
(First of all, he's confusing ozone with climate change. And which is more important, hair or the global climate?)

"Perhaps there's a minor effect, but I'm not a big believer in man-made climate change." (Washington Post, 21 March, 2016)

"I'm still open-minded. Nobody really knows." (Fox News Sunday, December 11, 2016)

"President Trump is committed to eliminating harmful and unnecessary policies such as the Climate Action Plan..." (White House website, accessed January )

And looking to his pick for leading the Environmental Protection Agency: Scott Pruitt
"Scientists continue to disagree about the degree and extent of global warming and its connection to the actions of mankind." (National Review, May 17, 2016)
(In fact there is a consensus among almost all scientists that global temperatures are rising and that it is because of mankind: Skeptical science: Climate consensus)

Secretary of Energy: Rick Perry
"It's all one contrived phony mess that is falling apart under its own weight," (2010 book: Fed Up! Our Fight to Save America from Washington)

Attorney general: Jeff Sessions
"I believe there are legitimate disputes about the validity and extent of global warming … Carbon dioxide does not hurt you. We have to have it in the atmosphere. It is what plants breathe. In fact, the more carbon dioxide that exists, the faster plants grow." (Senate floor, 2003)
(The last part is obviously true. Plants also need water, but water can make you drown!)

Then there is Secretary of State Rex Tillerson, former CEO of Exxon Mobile who are being sued for climate change cover up. He was awarded the Russian Order of Friendship medal in 2013.

The cold war is most likely over, and now the Warm War has begun. This time, we have corporate interests uniting with people who believe in absolute freedom from regulation. While the US and Russia went head to head in the Cold War, they could be allies in the Warm War. The US has big corporations and Russia has little to lose and a lot to gain from global warming. 

Here is some basic physics telling us what will happen if the world gets warmer. Higher temperatures mean less ice. The sheets on Antarctica and on Greenland and other landmasses in the Arctic will melt and the sea level will rise. Many of the world's cities are on the coast. Russia's coastal cities are at risk, but Moscow should be safe. There is also a lot of frozen tundra that could thaw, and sea channels to the north of Russia that will open when the arctic ocean stops freezing over. 

Also with rising temperature there will be more evaporation from sea, leading to more moisture in the atmosphere. What goes up comes down, so there will be more rain, and heavier rainfall. An example of this already happening is the increasing floods in the UK. And heat is energy, and more energy means more weather, stronger storms and higher winds. And more energy means more chaos.

This is about as much as I could get through in the time available. I had much more to say, especially about the pathology of climate denial, but I had spent all the time getting to the topic. There were a few questions afterwards. Someone asked about the effects on the ocean, which I said I was very concerned about. I mentioned that bleaching had been observed on something like 70% of Okinawa's coral, which many people nodded about. 

And the big question was what to do about it. The most important thing, I told them, was to know what is happening. If you are an alcoholic, the first thing to do is to admit you have a problem. 

As people were leaving I heard someone saying that he thought global warming was probably just nonsense, and that it was all because of the sun's activity. Given more time to speak, or more time to prepare I would have addressed that exact point, and showed some scientific journals devoted to people researching solar activity. If there was any chance at all that solar activity could explain the facts of climate change then they would be jumping up and down shouting: "Over here! over here!" But they are not.  

Maybe next time.

References



Climate references 

Climate and politics





Answer: 
One litre of oil produces 2.5 kg of Carbon Dioxide. Yes that's more than twice its own weight. Oil is almost all carbon, and when it burns each atom combines with two oxygen atoms from the atmosphere.