Replies to questions about climate science

One Terry today at The Australian asked some questions. Unfortunately the paper is a lousy forum to conduct a conversation because it updates slowly and is patchy in posting comments. Also, Terry, the answers to your questions are readily available. It’s not my fault if Australia’s only national daily doesn’t report science much above the level of superstition and rumour. I would offer my humblest grovelling apologies if it were my fault. For that, you must go to Mr Murdoch.

Tom Clark, Philip Machanick, Sancho, et al

Why not settle the discussion and show us sceptics the proof for the following:
1. That current anthropogenic CO2 emissions are the major cause of global warming. Bear in mind that the physics shows that the amount of warming from CO2 decreases as the concentration increases. Thus there has to be a huge forcing, what is it?
2. That the minimal warming from anthropogenic CO2 causes climate change. Please detail which elements of the climate (storms, drought, heat, floods, tornadoes, etc.) are changing, and the proof that the major cause is anthropogenic CO2.
3. The earth has been warmer in its recent past (Roman and Medieval periods), and these warm periods were very beneficial to mankind. Thus if (and it’s a big if) anthropogenic CO2 has any real influence on the global temperature, why should we be concerned about living in temperatures that existed, to the benefit of mankind, in the past 2000 years?

When you answer, bear in mind that computer predictions are not science.
Also the recent (30 years) global temperature readings are badly compromised, not least from the fact that the original 6000 measuring sites have been reduced to 1500, and it wasn’t the warmest locations that were removed.

Just this once, I’ll do your homework for you. But listen up: you can find all this stuff yourself. The trick is to use Google Scholar, rather than regular Google, which turns up masses of dross. Unfortunately a good fraction of the research literature is paywalled, but NASA makes all theirs public so I will use them disproportionately so you can check my sources. I include a few paywalled papers where the important detail is in the free to view abstract.

1. Scientists have known since the 19th century that the relationship between CO₂ concentration and warming is logarithmic. Please don’t parade this fact as evidence of the ignorance of scientists, but rather as evidence of your ignorance of the mainstream. Forcing per doubling of CO₂ is 4W/m² [Hansen et al. 2005]. To put this into context, a 2% increase in solar irradiance adds about 4W/m² [Hansen et al. 2008]. A 24 W/m² increase in solar irradiance only over summer, accompanied by a 4-day increase in the duration of summer, caused by a change in axial tilt [Huybers 2006], is enough to tip the earth out of an ice age, so 4W/m² is a big change – especially as it’s not limited to one season and a limited part of the planet. The maximum variance in solar irradiance since satellite records began is 0.36%, less if you smooth the data to take into account that the biggest variations are very short-term (graph below from TSI Composite Database plot of data 1978-1999). There is no known theory of climate that can use solar variability and other natural influences to reproduce temperature variation since the 1950s. We can only reproduce the trend by models that include natural influences and anthropogenic warming.

2. No serious climate scientist is claiming that the current level of warming is resulting in major increases in storms etc. Yet. There are however measurable effects like loss of Greenland and Antarctic ice mass [Velicogna 2009 – see figures from this paper below] – and many others like glacier retreat, change in species range, and accelerated rates of extinction. You can find plenty of evidence for these if you look. If you want catastrophic effects before you accept firm evidence of climate change, you’re crazy. Predictable effects such as shrinking glaciers are enough for me, especially as many of these metrics are happening faster than predicted.

Antarctic Ice Loss (blue data points: unfiltered)	Greenland Ice Loss (blue data points: unfiltered)

3. The evidence of warming in the Medieval Warm Period is patchy and unreliable, and recent evidence suggests the warming was not as fast as that at present [Loso et al. 2007]. A conspiracy-theoretic site styling itself “CO2 science” has an extensive archive of papers purporting to support a globally warmer period in medieval times. I examined the papers they claimed had the highest-quality evidence, and found the temperature peaks varied by as much as 600 years in different locations around the world. That is not a globally warm period. I haven’t seen the evidence that Europe was warmer in Roman times than it is now; there certainly is unlikely to be solid evidence of warming on a worldwide scale for the simple reason that the resolution of our methods of measuring temperature is poor that far back in time. In any case, “warmer” is a relative term. Our current temperatures are on the back of greenhouse warming that hasn’t concluded. Even if we do not add more CO₂ to the atmosphere, we have another 0.5°C of warming or so due from slower feedbacks. The Roman world and Medieval Europe may have benefited from local warming from a sub-optimal climate for agriculture to a better climate for agriculture. Warming today is unlikely to have that effect: much of the world’s rice crop for example is grown at close to its temperature limits for high yields, a concern for food production in China [Tao et al. 2006].

On your other comments, if computer predictions aren’t science, we are going to have to stop doing biology and most other branches of modern science. Computer models are no different than mathematical models, except they can process a lot of information fast. Like mathematical models, they can be wrong. This is why scientists check on each other, and build their own models from scratch, rather than rely on a popular model to be correct.

The claim that measurements are compromised by reduction in climate stations is rubbish, especially the claim that the removed sites were from cooler areas. Temperature measurements are not in absolute readings, but anomalies, deviations from a baseline. The baseline for each weather station is based on typical measurements for that type of station. The number used from each station in the overall temperature calculation is not its temperature but its difference from the baseline. This method was introduced for several reasons, one of which is to avoid exactly the sort of problem to which you allude. NASA documents their approach in detail and provides all the computer programs and data. Check it yourself.

 I have a question for you now:

If climate science really is junk, why is it necessary to oppose it with vaudeville acts, personal attacks, stealing email and clear and obvious lies?

And if you agree with me is that science is about supporting theories with evidence, not personal attack and harassing scientists with whom you disagree, sign my petition.

References

[Hansen et al. 2005] Hansen, J., Mki. Sato, R. Ruedy, L. Nazarenko, A. Lacis, G.A. Schmidt, G. Russell, I. Aleinov, M. Bauer, SS. Bauer, N. Bell, B. Cairns, V. Canuto, M. Chandler, Y. Cheng, A. Del Genio, G. Faluvegi, E. Fleming, A. Friend, T. Hall, C. Jackman, M. Kelley, N. Kiang, D. Koch, J. Lean, J. Lerner, K. Lo, S. Menon, R. Miller, P. Minnis, T. Novakov, V. Oinas, Ja. Perlwitz, Ju. Perlwitz, D. Rind, A. Romanou, D. Shindell, P. Stone, S. Sun, N. Tausnev, D. Thresher, B. Wielicki, T. Wong, M. Yao, and S. Zhang 2005. Efficacy of climate forcings. J. Geophys. Res. 110, D18104, doi:10.1029/2005JD005776
[Hansen et al. 2008] Hansen, J., Mki. Sato, P. Kharecha, D. Beerling, R. Berner, V. Masson-Delmotte, M. Pagani, M. Raymo, D.L. Royer, and J.C. Zachos, 2008: Target atmospheric CO₂: Where should humanity aim? Open Atmos. Sci. J., 2, 217-231, doi:10.2174/1874282300802010217
[Huybers 2006] Peter Huybers. Early Pleistocene Glacial Cycles and the Integrated Summer Insolation Forcing, Science 313 (5786), 508, 28 July. [DOI: 10.1126/science.1125249]
 [Loso et al. 2007] MG Loso, RS Anderson, SP Anderson, PJ Reimer, P J. Sediments Exposed by Drainage of a Collapsing Glacier-Dammed Lake Show That Contemporary Summer Temperatures and Glacier Retreat Exceed the Medieval Warm Period in Southern Alaska, Eos Trans. AGU, 88(52), Fall Meet. Suppl., Abstract PP44A-01
[Tao et al. 2006] Fulu Tao, Masayuki Yokozawa, Yinlong Xu, Yousay Hayashi, Zhao Zhang, Climate changes and trends in phenology and yields of field crops in China, 1981-2000, Agricultural and Forest Meteorology, Volume 138, Issues 1-4, 29 August, Pages 82-92, ISSN 0168-1923, DOI: 10.1016/j.agrformet.2006.03.014
[Velicogna 2009] I Velicogna. Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE, Geophys. Res. Lett., 36, L19503, doi:10.1029/2009GL040222

Climate of Fraud

I saw Bob Carter, a leading opponent of climate science, on SBS TV (semi-commercial government-owned channel in Australia) news tonight (13 August 2009). Shortly afterwards, the view switched to a slide carrying the claim that the IPCC’s models “predict monotonic warming, and they are wrong”. Here is the slide, captured from the online edition of the news (about 1:18 in from the start):

This is a blatant lie.

I reproduce here a graph from the IPCC’s 2007 report [Randall et al. 2007]:



A “monotonic increase” means that temperatures can only increase over time, with a possibility that they may stay level at times. Examine the graph. The yellow area represents results from 58 simulations. The black line is the actual temperature record and the red line the average of the simulations. What you can observe is that the yellow lines and their average, the yellow line, do not either increase or at least fail to drop over the entire period of the simulation.

Indeed it would be bizarre if any reasonable approximation to the real climate showed a monotonic temperature increase, unless that increase was so extreme as to overwhelm all natural variation, and no serious climate scientist is making any such claim. It is widely known that the two major short-term influences on temperature are the El Niño Southern Oscillation (ENSO) and the solar cycle. This is why climatologists define the climate as the long-term average. It is a shift in the long-term average that is a concern, not whether temperatures increase every year.

Why is the Carter crew claiming that the theory demands this? Because they want to knock the theory down, and have no evidence to the contrary, so they have no option but to lie.

That he is trundling this stuff out along with cronies from the right wing US Heartland Institute at a time when there is political activity around climate change is no surprise. That they cannot do better is. Professional science obfuscators – including Heartland – confused the public for years around the link between tobacco and cancer without resorting such obvious falsehoods.

[Randall et al. 2007] Randall, D.A., R.A. Wood, S. Bony, R. Colman, T. Fichefet, J. Fyfe, V. Kattsov, A. Pitman, J. Shukla, J. Srinivasan, R.J. Stouffer, A. Sumi and K.E. Taylor, 2007: Climate Models and Their Evaluation. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge

If biofuels are the answer, what is the question?

One of the biggest problems with both climate change and the growing threat of peak oil is that it's all too easy to fall into the trap of subsidizing special interests, rather than actually tackling the real issues.

Either we accept that these problems are real (singly or collectively) and we focus on solutions, or we don't. In either case spending good money on non-solutions is idiotic. If there is a real problem, we need to solve it. If there isn't, why are we wasting valuable resources on unnecessary research, industries that don't stand up to competition and that, in any case, wouldn't solve the problem if it were real?

My own position is that there is far too little cause for doubt on climate change to mess around: we should stop navel contemplation and get on with solving the problem.

I am a little less certain on peak oil. Hubbert's original theory worked well for a single market, the US (he accurately predicted the US peak as 1970-5975). When US oil discovery peaked, it made sense for oil companies to switch their focus to other parts of the world, rather than pursue diminishing returns (oil that was harder to find, harder to extract, or both). The same equation does not apply worldwide: oil companies can't start exploring another planet for oil. So more expensive exploration and extraction in combination are very likely to push the peak well out beyond Hubbert's calculation.

However: the key issue is that we are starting to deplete the cheaper resources, coincidentally with massive growth in new economies (especially China but also India), so prices have only one way to go, and that is up. Add that to climate change, and there is a powerful argument to look for alternatives to fossil fuels.

Biofuels are at best a small part of the solution because there isn't unlimited agricultural land available to turn over to fuel production. At worst, they exacerbate the problem, as in countries like Malaysia and Indonesia where massive amounts of greenhouse gases are emitted through deforestation for oil palm plantations.

Wikipedia has an informative article on the world leader in ethanol, Brazil.

To put matters into perspective, world ethanol production in 2004 was 10,770-million gallons. In the same year, the US alone consumed nearly 14 times that amount of petrol (gasoline for American readers: over 3 billion barrels, about 140-billion US gallons).

Brazil is in a favourable position for growing a lot of sugarcane for fuel; it is unlikely that their production could be scaled up through enough other countries to make a meaningful dent in the problem, even if so doing would not displace food crops, or result in other environmental disasters.

The US could significantly increase available agricultural area for biofuel crops with a total cessation of feeding food, grown on land that could produce human food or energy crops, to farm animals. Not only would this be a more efficient form production, but the cows would have less fat, reducing the human obesity problem. However, it is only in comparatively wealthy countries that this kind of land exists for conversion. In poorer countries, cows eat grass. And not many countries are in the position of Brazil, with a significant fraction of farmland available for sugar cane.

In any case, oil, coal and biofuels are an incredibly inefficient way of storing solar energy. A plant stores between 3 and 6% of the incident solar energy, compared with solar cells, which are supposedly inefficient because they 'only' covert 15-20% to electricity (do a search on "solar cell efficiency": there are some far better efficiencies in research labs). Add in all the other losses from converting plants to a usable form of fuel and the losses from burning them to create the form of energy we actually want (motion, electricity, etc.) and they turn out to be incredibly inefficient. In the case of fossil fuels, the stupendous inefficiency of their production is masked by the fact that we waited hundreds of millions of years before bothering to use them.

If we can find an efficient way of storing electricity, we will solve the entire energy problem with the exception of the real hard case, air travel.

The long-term solution is energy sources that do not require burning carbon or hydrocarbons. If we are serious about dealing with climate change and the threat of peak oil, we should be putting massive resources into solving this problem. In any case, it's stupid to put waste big money on non-solutions.

Exxon-Mobil to abandon climate change obfuscation

I stumbled on this, probably not meant to be in a publicly accessible place. I hope ExxonMobil will not be too outraged if it appeared early on my blog.

-----EMBARGOED UNTIL April 1st, 2008-----

SPRINGFIELD--(BUSINESS WIRE)--April 1, 2008--Speaking today at City Hall, Springfield, C M Burns, President Corporate Affairs of Exxon Mobil Corporation (NYSE:XOM), announced a major change in ExxonMobil's approach to climate change.

Burns was speaking as part of Springfield's new Business Leaders Who Pay To Speak Program.

He described the actions ExxonMobil has taken in the past to obfuscate climate change science as "consistent with maximizing the corporation's profits. The modest cost of piggybacking onto tobacco and ozone hole denial has been an excellent investment. Excellent..."

Reaffirming ExxonMobil's commitment to being a constructive and active participant in dialogues concerning proposals to reduce greenhouse gas emissions, Burns outlined the de facto change in policy. "This time, we actually mean it. We came to the sudden realization that pretending the science was wrong would not save us if everyone is burned to a crisp. Bad for profits. Very bad."

He highlighted ExxonMobil's actions to increase confusion about climate science. These included giving financial support to groups claiming to represent "sound science". "Sound science," he explained, "is that which increases ExxonMobil's profits, no matter how tenuous or where published." These same groups, he continued, were paid to portray peer reviewed science as "junk science", no matter how well-founded, if it was contrary to ExxonMobil's interests.

In describing ExxonMobil's work with partners, Burns reported that the company is now planning on entering a new phase of supporting climate science that is accurate and not influenced by short-term concerns for profit. To facilitate this change, a blind trust to disburse research funds is being set up, to be headed by fabled jazz saxophonist, B.G. Murphy. Said Burns, "No one could imagine Murphy as advocating causes dangerous to the common good."

Steepling his fingers for emphasis, Burns concluded, "We must care enough to treat the risks of global warming seriously. We need to manage the risks of companies distorting the science effectively if we are to maximize the economic and environmental benefits available to future generations."

Full text of the speech is available on the ExxonMobil website. Some text copyright L Simpson.

###

NOTES TO EDITORS

* The Business Leaders Who Pay To Speak Program aims to encourage debate amongst senior business figures on issues where they are prepared to pay to be heard. The inaugural event took place in November 2007 and C Montgomery Burns was the second speaker in this Program. The first speaker was less gullible and merely bribed the press without bothering to show up.

* The International Energy Agency estimates that, by 2030, it is likely world energy demand will increase by 45 percent. This growth equates to about 100 million barrels of oil equivalent a day, which is in addition to the 240 million barrels oil equivalent a day currently consumed.

* No one with any sense actually believes that this amount of oil can continue to be extracted without running into limits, sometimes referred to as "peak oil".

CONTACT: ExxonMobil
Media Relations: Dallas (US) office, +1 972 444 1107
or
Leatherhead (UK) office, +44 1372 222261/74

SOURCE: Exxon Mobil Corporation