I had a day (well afternoon and evening) out of the home-office yesterday. I took the train to Cambridge and caught the first hour or so of a Cambridge Energy Forum on UK buildings before heading to the Guildhall for a well-attended public meeting on “what Copenhagen means for you”.
Maybe I’m an unreconstructed contrarian, but I find myself disagreeing with much of what I’m being told on the topic of global warming. Here are my latest musings.
What’s the target?
The Guildhall meeting started with a very competent whirlwind summary of the science of climate change by Emily Schuckburgh of the British Antarctic Survey. In particular she showed a rather longer graph than I’d seen before of historic temperatures and CO2 concentrations derived from ice-core analysis: around 800,000 years worth. During all this time the level of atmospheric CO2 had varied only between 180 and 280ppm, in close correlation with the temperature.
Furthermore, when temperatures have briefly spiked up during inter-glacials they have reached levels somewhat higher than at present (or in the entirety of recorded human history for that matter). Schuckburgh suggested temperatures may have been 4C higher than her baseline (presumably the pre-industrial average temperature, 0.8C lower than at present) for brief periods (and -8C lower during ice ages). Scary stuff.
Why then, do we think we’ll manage to keep temperatures within 2C of pre-industrial levels – and they’ve already risen 0.8C – at the sort of CO2 concentrations implied by the discussions at Copenhagen? We’re at around 390ppm right now and it doesn’t look like the proposed policies have much chance of keeping us below, at best, 450ppm.
And on top of that, CO2 isn’t the only greenhouse gas. Some have only just been invented! If we can’t get all the methane (CH4) and nitrous oxide (N2O) down to natural levels and the anthropogenic alphabet soup of CFCs, HFCs and so on down to negligible levels, then we’ll be even warmer.
Here’s my contrarian position (1): we need to get CO2 levels back down to the natural range of 180-280ppm. Presumably we’d aim for 280ppm, since 180 implies an ice age!
The theory – perhaps I should say hope – is that we can “stabilise” levels at 350ppm and a 2C temperature rise. This is wishful thinking poppycock. In fact, the climate system is not a stable one. In particular, it will not be stable at 350ppm and a 2C temperature increase. It will have a tendency to warm further, for example, as ice melts, darkening the planet’s surface; as CO2 levels rise further as forests burn in the occasional much hotter summers we’d experience; as wetlands dry out and release their carbon too; and as the ocean circulation gradually slows due to the reduced temperature differential between the poles and the equator, removing less and less carbon from the atmosphere as time goes on.
We’ve opened Pandora’s box – we have to put all the demons back in, not just some of them.
Will the Gulf Stream slow and keep Britain cool?
This was meant to be a post about policy, but I’ll get the other science point out of the way, since this old chestnut came up in the Q&A at the Guildhall.
The point is that the Gulf Stream (as the North Atlantic branch of the ocean’s circulation is popularly known) can be disrupted by lots of fresh water flowing into the North Atlantic. Such water floats (because it’s fresh which makes it lighter, even though it’s cold which tends to make it heavier) and would prevent the circulation whereby (salty) cold water sinks as it approaches the pole, drawing more warm surface water up from equatorial regions, keeping Northern Europe, including the UK, a lot warmer than other regions at such a high latitude.
As the world emerged from the last ice age (and previous ones), it seems vast quantities of meltwater from the North American ice-sheet poured into the North Atlantic as ice-dams gave way. This disrupted the oceanic circulation and caused warming to reverse for a while, at least in the North Atlantic region.
It’s possible that meltwater from Greenland could have a similar effect to that from Canada, but unless someone’s asleep on the job, this isn’t imminent, since we’d see the water pooling in Greenland.
So, what will happen to the Gulf Stream in the absence of disruption from a sudden flood of meltwaters?
Here’s my contrarian position (2): the ocean circulation will strengthen in the short-term (which, depending largely on future greenhouse gas emissions, is likely to be a century or two), then gradually weaken as the ice-caps disappear. There’s no get out of jail free card for the UK, certainly not in our life-times.
The point is that the circulation is ultimately driven by the temperature difference between polar and equatorial regions.
More heat is captured by the atmosphere in the tropics than at the poles, that’s why you have a circulation in the first place. With the presence of greenhouse gases, even more heat is captured in equatorial regions and tends to be transported poleward either in the oceans or the atmosphere. More warm water stays near the surface until it cools as it approaches the poles. The result is a stronger circulation.
The presence of ice (Antarctica, Greenland, permafrost) keeps the polar regions from warming. Until this ice melts, more heat will be transported poleward. Indeed, the heat uptake by ice melt that drives the circulation.
Of course, the heat transport itself progressively melts the ice. When it’s eventually all gone, temperatures will tend to equalise between the poles and the equator, weakening the circulation. We’re not there yet, though.
I should remind readers that the ocean circulation is one of the major ways in which carbon dioxide is removed from the atmosphere.
[5/11/09 Afterthought: Oops, this throwaway comment could be a bit misleading. In fact, the ocean circulation returns CO2 to the atmosphere, so, if the circulation increases in strength, as I’m suggesting it will over the next century or two, the net effect will be for the ocean to take up less CO2 (net, the oceans are currently absorbing CO2 because the ocean and atmosphere are out of equilibrium because of the “extra” anthropogenic CO2 in the atmosphere). This mechanism represents a positive feedback during deglaciation warming phases, and, if my hypothesis is correct, during the current phase of global warming. When the ocean circulation is interrupted, then there is a positive cooling feedback as the ocean releases less CO2 due to the reduced circulation, taking up more net. This could explain the persistence of cooling phases during deglaciations (warming periods after ice ages), such as the 1000 year long Younger Dryas event.].
Therefore, as I said in my first heresy, we’d better get temperatures and CO2 levels back down before the ocean circulation strengthens too much. [5/11/09: Amended this sentence, see previous note in square brackets].
Burning wood is not a good idea
Everyone loves Julian Alwood! (He taught on my MBA programme). He told an amusing anecdote yesterday about how some well-meaning foreigners had tried to introduce a more efficient stove in Malawi. The problem was Malawians bash the meat while its cooking, apparently, and the new stoves didn’t last very long.
But the main point is that the big problem in Africa is burning wood. It releases carbon (and, almost as important, retains moisture). “Reducing deforestation” (George Orwell would have loved the double negative!) was mentioned by Chris Hope, among others, yesterday as the cheapest way to avoid deforestation. What’s really needed in Africa is a robust solar stove design, but more about that another time.
So why then was a picture shown at the Cambridge Energy Forum of a supposedly virtuous Briton carrying some logs to put on his fire?
I’ve harped on about the biofuel topic on this blog previously and will no doubt do so again (see the Biofuel category in the box on the right), but here’s my contrarian position (3): Everyone should avoid the use of all forms of biomass as fuel.
Here’s something you may have missed. A radio programme a day or two ago was discussing a satellite that has just been launched to detect moisture levels from space. The point was made that if forecasters had realised that European soil moisture levels were so low in 2003 they would have been able to forecast that year’s heatwave much more accurately.
Interesting factoid. I don’t know about you, but it suggests to me that one way we could adapt to global warming here in Europe is to increase soil moisture levels. How do we do that? More trees (including decaying ones), less arable farming, that’s how. And how do we achieve that change? We ban agrofuels (the right-on term for biofuels) and discourage biomass burning. Simple isn’t it, when you think things through?
Trying to reduce UK (or other comparable country’s) energy consumption is a waste of time, effort and money
I have to say I was stunned by the facts and figures thrown at me by the Cambridge Energy Forum (and in Michael Kelly’s talk on a similar topic in the Guildhall). I think they’ll put up a report of the meeting and slides on their site, in due course, so I won’t try to cover everything that was said.
Let it suffice for me to report that improving the energy efficiency of the UK’s housing stock turns out to be a Sisyphean task. (And even if we succeeded, energy consumption would tend to rebound as we spent the money saved! I won’t go into all this again – my most recent post on the topic is here). After you’ve insulated the loft and put in the low-energy lightbulbs – and anyone who doesn’t take the simple steps is an idiot – it starts to get really expensive.
And you can’t wait for new low-energy houses to be built to replace the existing housing stock because that would take 20,000 years. Or something.
The UK will not reduce its energy consumption by 50%. It won’t happen. The effort is futile. It’s a dead parrot of a policy.
The reason is economics. Importing solar-generated electricity can be achieved at a fraction of the cost per kWh. Promoting that sort of scheme is what everyone should be putting their effort into. And the Desertec plan was only mentioned once, en passant, in the Guildhall.
And then there are the economic reasons. People want to be richer, not poorer. They don’t want to be turning their thermostats down. And what’s more, people are tending to get richer over time – despite a raft of policies promoted by governments round the world designed by a secret global committee with the objective of halting this process – ultimately because technological (and learning) advances mean productivity tends to steadily increase (especially when regular economic recessions purge the least efficient).
The fact that more people are getting richer all the time suggests that policies based on changing people’s behaviour through taxation have had their day. We need to think again about behavioural taxes on everything from alcohol to carbon.
The main advantage (probably the only one, at least in this contrarian’s view) of a carbon tax (championed by the even more lovable Chris Hope last night), or any other way of pricing carbon, is that it makes dirty energy more expensive than clean energy, encouraging companies to invest in renewable energy production. This presupposes, though, that the main reason companies aren’t investing in renewable energy projects is price. And when I read in New Scientist magazine on the train home that “over 5 gigawatts of [UK] wind power are currently stalled by aviators’ objections” to possible radar interference alone, I really wonder whether price rather than the planning system really is the problem.
Nevertheless, internalising the carbon cost must be part of the solution. The problem with introducing a UK tax on carbon is that it will use up an enormous amount of political capital. To be effective there would have to be a huge shift to carbon taxes. And I can see the headlines already. “Driving is just for the rich in Cameron’s Britain”! Not going to happen, is it?
People certainly don’t like being morally preached at (as Chris Hope pointed out), but they like being taxed, and changes to how they’re taxed, even less.
The problem with a tax on carbon in general is that it sets no limit on emissions – so, since a tax simply redistributes spending power, could turn out to be ineffective.
A lot of intellectual effort seems to be going into working out what is the “right” price for carbon. The Kyoto idea of carbon trading may have had a lot of problems, but the principle of letting the market determine the carbon price (by squeezing supply) was the right one.
So what’s my contrarian position? OK (4): Right now energy policy should focus entirely on removing all obstacles to the development and roll-out of renewable forms of energy. Let’s see how far that gets us.
Guilt is not an appropriate emotion for dealing with this problem
Chris Hope was the only one last night who explicitly mentioned that the West caused the problem and should pay to fix it.
Well, I’m sure that “from each according to their abilities”, despite its connotations, might be a principle that could reasonably be applied in the context of international climate change negotiations. But what appears to be happening in the Copenhagen negotiations (I was hoping to find out more last night) is that the aid agenda has taken over the global warming agenda.
For starters, I don’t see a lot of evidence of binding emission targets being linked to these large transfers of money. But for the main course, we’ve brought some more presuppositions with us. There are serious doubts that aid is what’s needed to promote development. Yeap, for decades we’ve been following a seriously flawed policy. For example, Paul Kagame, President of Rwanda, wrote in yesterday’s Guardian, that “Africa must attract broad investment, not rely on handouts, if we are to sustain development”.
What’s needed is trade, not just aid.
Aah, you say, the Copenhagen largesse is investment. Well, maybe some of it will be spent wisely. But there is plenty of money in the world – too much in fact (that’s what caused the credit crisis) – looking for investment opportunities. Why do we need billions more?
A cynic, and I am one, so I’ll carry on, might even conclude that the $100bn or whatever comes out of the wash in Copenhagen, is in fact a further Keynesian stimulus for sluggish western economies. Think about it. Many of those pounds, dollars and euros are going to be spent on – to hazard a guess, as the details are not very clear – engineering projects that will be carried out by western companies. And I would have thought Gordon Brown (who’s driving this handout) is savvy enough to know this. Watch shares in Aggreko and Balfour Beatty when this deal is done!
And what happens when the money runs out? When we eventually decide we don’t need to pay developing countries for a climate deal, or decide that they’re not keeping their side of the bargain (whatever that is)? The money will be like aid, creating dependency.
On the other hand, and let’s call this my final contrarian position (5): paying for ecosystem services – and here’s some good news that could come out of Copenhagen – and/or energy, such as desert solar, will (if executed properly) provide countries with sustainable income streams which will support their further development.