Sunday, October 30, 2011

Climate change myths


There's a lot of rhetoric being poured out about the matter of climate change and the carbon tax. A large proportion of it is wrong... Here, briefly, are some of the myths about climate change. From BOTH sides. So whatever your views, prepare to be annoyed.

Myth 1: The earth has cooled for the last ten years so there's no such thing as climate change.
Climate is defined as the average of weather, or patterns of weather, measured over a long period of time - typically 30 years. Therefore it's self-evident that if global temperatures aren't the same today as they were ten years ago, climate change HAS been happening.

Climate change is normal and has been for all of recorded history. I'm sure you're all familiar with the standard examples given by the deniers about the Thames freezing over and crops on Greenland. Here's mine - back in pioneer days parts of Australia were in drought for forty years or more. Since drought is defined as rainfall lower than the average over the past ten years, the average rainfall must have dropped fairly constantly for at least thirty years. That's climate change, right there.

Myth 2: Humans don't cause climate change, external factors do.
There's a new explanation every month or so - sunspots, volcanic activity, errors in measurement, cosmic rays, etc. The truth is, it's impossible to be scientific about this - we can't take a set of identical planets and test various theories while preserving a statistically adequate control group. We only have one planet, and if we break it we won't get another. It's quite possible that external factors affect earth's climate, but that doesn't prove that anthropogenic CO2 doesn't also have an effect.

Myth 3: The East Anglia CRU deleted their records, they must know there's nothing in it
Even if the blatant assumption in that statement is true, why should we trust those scientists rather than any others? There's plenty out there that say they know it's true, and others that say they know it's not. Let's concentrate on the facts, not on what people say about the facts.

Myth 4: Scientists have to say they believe in climate change or they don't get any grant money
There's an old and wise saying, "Never attribute to conspiracy that which can be reasonably explained by stupidity". Yes, there might very well be a conspiracy about climate change. But that kind of paranoia doesn't do any good for anyone. Once again, concentrate on facts.

Myth 5: Nobody could agree to cut emissions at Copenhagen or Cancun so let's not do anything
Your mother is inside my head yelling "If all your friends jumped off a cliff would you jump too?"

There are a lot of very powerful vested interests in the emissions business. But science has nothing to do with who can lobby their government better. Facts, remember those things?

Myth 6: Higher CO2 levels in the atmosphere cause warming, the Mythbusters proved this!
Yes that's true - but the argument between scientists (reputable ones) on the two sides of the fence is nothing to do with the direct effect of CO2 emissions. It's all about the "feedback effect" theory - the effect of higher global temperatures on atmospheric CO2. Some scientists say there is a positive feedback - that a hotter planet will naturally put more CO2 into its own atmosphere, eg by increased volcanic activity and more animal life. Others say the feedback is negative - that heat causes water vapour to condense into clouds and reflect solar energy back into space, cooling the planet back to its original temperature.

The problem is, we can't do a proper scientific study to determine the magnitude of the feedback effect because (again) we only have one planet. The strategy is (and this is what the East Anglia CRU were doing) to collate data on all the factors that influence global temperatures and then run statistical analysis on them to find a number that fits - the popular press calls it "computer modelling".

A significant complicating factor is that the measurement of historic global temperatures over thousands of years has a lot of unprovable assumptions built in. Satellite IR readings (obviously) weren't around back then, so they're estimated from things like the amount of pollen in coal seams and polar ice cores, which is a rough indicator of plant activity which should vary directly with global temperatures. The possibility for errors to creep in is huge but it's the best we can go on.

Myth 7: Even if it turns out there's nothing to be afraid of, isn't it better safe than sorry?
Yes - to an extent. But if it's going to take a carbon price of $100/tonne (the level at which baseload wind power becomes commercially viable) to keep CO2 levels down, we have to turn the same question around - even if it turns out carbon pricing won't take our economy back to the stone age, isn't it better safe than sorry?

I have no problem with encouraging people to reduce their consumption. Western society is so wasteful of all sorts of things - turn the lights off when you leave the room for goodness sake! I also have no problem with substituting other materials for plastics where possible - timber, cotton, rubber, paper, etc all use less energy to produce than plastics and would be suitable in a good proportion of applications. These things will improve our planet regardless of climate change.

But a carbon price will do damage - after all, that's what it's there for. It's supposed to provide a financial incentive to reduce CO2 emissions. Since we can't eliminate all emissions it's going to cost us. The compensation won't work either - it will only cover the direct costs to the household, not the accumulated costs incurred at every step in the chain by businesses.

The key word in this is "safe". Yes it's better safe than sorry, but a price on carbon isn't safe.

Myth 8: We have to do it for the island nations
Yes, there are low-lying countries that don't have the option of moving further inland to get away from rising sea levels. But it really makes no difference - if the sea levels rise most of Australia's population will have to up stakes and move too (see, for instance, http://rmit.com.au/browse%3BID=6tha567p4mcaz). Of course we have somewhere to go, but still it's something we want to avoid. If we're going to do it, we're doing it for ourselves as much as anyone else.

Myth 9: Financial control in the form of a price on carbon is the most effective way to reduce emissions
It's true that the hip pocket is the most sensitive part of an Aussie's anatomy, but the emission reduction will happen after someone a) feels the pain and decides to act, b) succeeds in finding a way of doing business which emits less CO2, and c) rolls it out. That process can take years, and all the while we're paying a government department to watch the money go round and round for nothing. A highly inefficient method, if you ask me.


Also, let's just focus on step a up there - someone has to feel the pain and decide to act. Has anyone seen the price of petrol lately? Has it gone up? Have you all (those of you who drive) felt the pain? What have you done about it? The shift toward public transport and more efficient cars has been small to insignificant. Why should a carbon price be any more successful?


Myth 10: Climate scientists have access to all the information and resources, and we don't - surely they're more likely to be right?
It's not the information and resources that are the problem, it's the difficulty of measuring the feedback effect. Scientists applying correct science (using all the available information at the time) but an incorrect feedback value have predicted things like snowfalls becoming a rare occurrence "within a few years", an ice-free north pole by 2000, no sea life by 1980, etc.


So that's my take on the science. In brief, it's that most scientists agree on the essentials, with the exception of the one controlling factor - the feedback effect. Next step - what should we do about it?

I'm not one of the skeptics that says "Since we can't prove 100% that there IS a problem I want to do nothing until it's too late". I'm also not one of the alarmists that says "Something must be done, this is something, therefore we must do it". We need to guard against runaway CO2 levels without completely destroying the advantages of Western society.

Option 1: The Carbon Tax as currently proposed
$23 a tonne is not enough to provide an incentive for significant moves towards reduced CO2 emissions, and yet it will raise the cost of living significantly. Inflated power prices will raise the cost of doing business at every step in the chain, and that will all be passed on to the final customer. The sum total will be much higher than the proposed compensation, which will only cover the direct cost increases on things like electricity.

Also, as I outlined above, the effect of financial controls on emissions is a delayed one.


Option 2: Carbon Trading as we're supposed to move to after a few years
This is probably slightly better than a tax, because it doesn't have the "sin tax" problem, where a government needs the revenue stream and therefore doesn't have an incentive to stamp it out. However it's still a price on carbon and has the same disadvantages as a tax.


Also, it's such a complicated system that extensive measures will be needed to prevent rorting. This will cause the administrative overhead to further increase the burden on the economy.

Option 3: Investment, eg replacing coal power plants with something cleaner
Usually it's wind and solar generators which are proposed, as they are sustainable and technologically mature enough for commercial-scale application. However they don't provide baseload power - only thermal and nuclear plants can do that. (For a quick run-down on the ins and outs of power generation see http://www.youtube.com/user/acmeschool#p/u/50/fOnXI9eoAxI - based on the North American power grid but the concept of baseload vs demand power is valid here too.)

I personally think nuclear is not for us. If the normally conscientious Japanese decided to cut corners on safety at Fukushima, what will she'll-be-right-mate-if-it-ain't-broke-don't-fix-it Aussies do?

Of course a lot can still be done with thermal plants to clean them up - there's been fifty years of thermodynamics technology since they were built. Also, some people have proposed natural gas power. Fundamentally the chemical reaction is the same - carbon plus oxygen yeilds CO2 in an exothermic reaction. The engineers should decide whether cleaner coal or gas gives a better bang per buck.

Option 4: Sequestration - preventing emissions from getting into the atmosphere
It's a technology with potential, although as yet it's still in beta (if that). It will come at a cost, both in development and implementation. Will it be better than some of the other options?

Also, unless the equipment could be made small enough, it would be limited to fixed sources of emissions - power generation and heavy industries, but not transport. Since transport comprises a large percentage of Australia's emissions sequestration is probably not the most effective strategy available.

5. Offset - planting trees to slurp up all that excess CO2
There are lots of struggling farmers who would be happy to do the whole job for you - just send over a truckload of saplings and pay them the minimum hourly wage for the whole job (it's more than they'd earn from raising sheep). In round figures a sapling costs $1 (that's retail though, the government could get them in bulk) and absorbs a tonne of CO2 over its life. A tree will start removing CO2 from the atmosphere today, not some time in the future when the hit to the hip pocket encourages someone to find a smarter way to work.


As a bonus it will provide rural employment which is always a good thing to encourage, and if the farmers are smart it might even help them rehabilitate a bushfire-damaged paddock.



As you might have guessed I'm in favour of options 3 and 5. But who listens to me?