Three things I didn’t realise about global warming

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with David Hines

Three things I didn’t realise about Global Warming
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There are three things I didn’t realise about global warming, and they were all presented at the Sea of Faith  Conference in Upper Hutt in October. The speaker was an engineer,  Geoff Henderson, and I think that’s what gave it such a different angle.

He said there was a lot of optimism round the world in early 90s that the need to phase out fossil fuels would be picked up globally. That came to a head in the Kyoto protocol in 1997 – an international agreement to cut down on the emission of gases that lead to global warming. But unfortunately, he said, there has been little progress since then.

And he said there were three reasons for this, of which the first was most striking to me… I had wondered why global warming could be such a problem, when it was all about things like the world getting half a degree warmer.

Figures of global warming over two hundred years.

Henderson gave figures of how much global warming there was over the 20th century, and how much was likely in the 21st century

In the first quarter of the 20th century the average surface temperature of the earth was

(1900-1925) 13.6 degrees

(1925-50) in the next 25 years it rose to 13.7

From 1950-1975 it rose to 13.9

And in the last quarter 1975-2000 it rose to 14.2

But that is only half a degree in 100 years!!

Then from

2000-2025 it’s expected to rise to 14.5

from 2025-2050 it’s set to rise to 14.6

2050-2075 itll’ reach 14.7

And in the lastquarter it’ll reach 14.8%, ie only a third of a degree in 100years.

So where’s theproblem? The temperature this morning has risen about 2 degrees, and we can live in 14.8 degrees. It’s quite a nice temperature.

So Henderson explained the problem is “isothermal warming” where the temperature stays nearly the same, but there are still massive amount of heat being transferred.

He gave a simple example …. when you heat a saucepan of water, it rises to 100 degrees, and if you keep on heating it, it still stays at 100 degrees….. because all the extra heat is turning the water into steam…It’s such an even process that we use this to keep the water temperature constant while we boil an egg. Boiling water doesn’t change its temperature.

Another isothermal process is water turning into ice … you can keep on taking energy out of the water, but it doesn’t get any colder than zero degrees Celsius. Because all the energy is going into melting the ice.

In the same way with the atmosphere, it doesn’t get much warmer, because all that extra energy is going into the sea … and the sea doesn’t get that much warmer, because all its extra energy is going into the ice at the north and south poles.

And that’s something we can see already, the huge loss of ice around the north pole…. and that is leading to a steady rise in the sea level. And in coming decades, the sea level will rise exponentially.

So up to the end of the 19th century (I think from ….the beginning of that century the sea level rose two centimetres. Which you would hardly notice.

But since then it has risen 20 centimetres…. you would notice that if you had built something on the edge of the sea, but not otherwise. Because the tide already goes up and down much more than that in a single day.

But the sea level could rise more than three metres by the end of this century, and that you would notice.

So the important things to monitor may not be surface temperature, but CO2 levels, and sea levels.

So there are four stages of global warming:

  1. A small temperature rise wold start the process.
  2. In stage two only floating ice would melt, while the ocean temperature and sea level would hardly change.
  3. In stage three land-based ice would also melt; temperature would barely change but sea level would increase 80 metres. That’s not by the end of the century; it’s whenever Antarctica runs out of ice. (Editors Note: millennia).
  4. And the worst is stage four. When all the ice has gone; everything will heat up more quickly.

I took the saucepan example a stage further …. when all the water has gone …. you start melting the saucepan; and had better take it off the stove double quick.

Henderson said: We are now in stage three. With ice melting rapidly in Greenland and Antarctica.

So that’s the first fact that was surprising to me … how these tiny changes in the atmosphere, hide bigger changes in the sea, and even bigger changes in the ice and sea level.

Second fact: which he calls the logic of action

He admits there is uncertainty in all these numbers. Especially looking at the future ….

So what you do about this uncertainty? Should you say, we’re not certain, so we should wait and see… or just say it’s too hard to work out.

Henderson says what we need to do is to put a cost on the alternatives. And here he lost me in the detail, but I got the general hang of it.

We may not be certain how much the surface will rise, but you can put a probability on it.

And you may not be certain how much the sea level will rise but you can put a probability on that.

And all those probabilities add up to 1 ….. that something along these lines is going to happen.

And the person who says the level of global warming is uncertain so you can ignore it is sending the world into a disaster.

And you can then put a cost on these scenarios.

If you do nothing, the cost is zero, but the harm is certain.

If the sea rises five metres by the end of the century, it would destroy London, shanghai and many other coastal cities. Let’s say that has a 60% chance of happening, we can calculate the cost of that.

And he says that leaves a 1% chance of even more terrifying scenarios, such as runaway greenhouse effects, or mass extinction.

At some point the harm would be so high; that it would outweigh the cost saving, and we would have to take action.

He says the fallacy of climate change denial is it only considers one of these risk scenarios.

On the bright side

On the bright side, he says change is not all costly, by creating new cleaner industries, it will offset the costs of phasing out old industries.

He says we didn’t leave them stone age because we ran out of stones …. and we wont leave the fossil age because we’re running out of fossils. We will leave it when the costs of using them outweigh the benefits.

3. The solution is economic

And that leads on tohis third and final point. Why do we use fossil fuels. Because of the cost benefits we see.

But this is harming us, so we need to make the fossil fuels dearer, until it covers the cost of the harm done.

But they are harming us, but are also not sustainable… it took hundreds of millions of years to create these fossils; that we have used up in only 300 years.

But solar energy, in the form of direct sunshine, wind power, hydro power, and biofuel… provides 178,000 Terawatts all day every day, which is more than 5000 times the energy we use.

Henderson stressed that we already have the technology to provide alternative sources of energy ….. we just need to put economic pressure to make people use them.

To make solar power economic, we need to force users to pay the costs of cleaning up the damage done by fossil fuels.

This has already been considered: in the resource management act, and in the Taranaki combined cycle power station; where trees had to be planted to balance the environmental cost of the power produced. This proposal was effectively dropped in 1994. Not a single tree was planted.

WE need a Tradeable Absorption Obligation, or TAO. it would have four results:

  1. it would cause major afforestation
  2. CO2 levels would be controlled.
  3. a large amount of biomass would be created.
  4. the price of fossil fuels will increase

Wood will still be used for fuel; it is more efficient, it is storable energy.

Update on costs and benefits

 Updating that third point …. it was in the news a week ago that the Wellington City Council had done a cost benefit analysis for the risks of sea level rise in Petone …. which is a suburb in the east of Port Nicholson, and very low-lying. The council predicted that before Petone disappears under the sea … it will be uninsurable. The insurance companies will have done their sums, and the cost of repairing a flooded house will put premiums so high, that people won’t be able to afford them, and the insurance companies will stop insuring them.

How important is religious motivation

And I would add a fifth point. religious motivation.

At the Auckland Sea Of Faith annual meeting last month, a group of us gave reports on the speakers we’d heard the month before. And I got to speak on this one.

Later that night we were looking at suitable subjects for speakers for next year.

One person who is a theological lecturer …. said he thought we should have fewer lecturers on topics like the environment, and more on theological and faith issues.

I got up and said: I thought we should have more lectures on issues of the day, like civil rights and the environment, and fewer lectures on theology.

This theologian wasn’t denying climate change, but he was denying that it was a suitable subject fora religiously minded group.

I would again say the opposite … that an issue about climate change is political will, or people’s belief systems, and this is something that Sea of Faith and this church can do ….. help to bring topical issues into the open and educate each other about them.

Some examples of climate issues getting into politics have been happening just this past week:

  • One was in France, where the government was putting up the price of petrol, and there were violent protests against the government.
  • In New Zealand we had a taste of the same. The government put on a series of road user taxes on places including Auckland …. which were largely accepted. But when the price of oil went up …. suddenly people wanted the government to remove the taxes it had imposed only a few weeks earlier.
  • An example from my own family. Earlier this year my wife Marion and I wanted to do our bit for climate change, so we sold our petrol car, and bought a hybrid car, which uses about 40% less petrol. We costed it: hybrid cars cost about $1,000 dearer but we thought we should pay that.
  • We also considered moving to a plug in car, which uses almost no petrol, but they were about $10,000 dearer, so we didn’t take that step.
  • A member of the congregation commented afterwards (as Unitarians are likely to do) and said that she had a plug in car, and it wasn’t any dearer because she got it from a small dealer who imports low use cars from Japan. In Japan they have government subsidies for plug in cars, but they also have a very high turnover of new cars, so their loss is our gain.
  • Another congregation member commented to me that electric cars don’t have a zero global warming cost, because it depends how the electricity is generated. I didn’t have the figures on me, but we agreed there are forms of power generation that do not harm the environment, like wind farms and solar panels, but the electric car is way cheaper in energy use.
  • And so are numerous other options that are available already …. heat pumps and double glazing among them.

But discussing these issues with friends, and in church is also a major tool in changing public opinion.

So let’s do it.