Ian Pilmer, an Australian geologist, wrote a book of which its premise is described as pointing out that climate research is driven by the prospect of research funding. Generally speaking, institution and government scientists make the same amount of money no matter what they study. Grant funding, unlike bailout money, goes to equipment and research work, not salaries and golden parachutes.
Ian Pilmer, Geologist
Rather than explain Pilmers position we opt to allow his arguments, and the well reasoned scientific response to his arguments stand as testament to the absurdity of his premise.
Plimer’s homework assignment
Some of you may be aware of George Monbiot’s so-far-unsuccessful attempt to pin down Ian Plimer on his ridiculous compendium of non-science. In response to Monbiot’s request for explanation and sources for some of Plimer’s more bizarre claims, Plimer has responded with a homework assignment that is clearly beyond even his (claimed) prowess. This is quite transparently a device to avoid dealing with Monbiot’s questions and is designed to lead to an argument along the lines of “Monbiot can’t answer these questions and so knows nothing about the science (and by the way, please don’t notice that I can’t cite any sources for my nonsense or even acknowledge that I can’t answer these questions either)”. (Chris Colose and Greenfyre have made similar points). It’s also worth pointing out as Andrew Dodds has done that each question is actually referencing a very well known contrarian and oft-debunked argument, but dressed up in pseudo-scientific complexity.
However, as a service both to Plimer and Monbiot (as well as anyone else interested), we give a quick scorecard on the relevance, actual scientific content (whether the questions can actually be answered) and sources for discussion for each of the, to be charitable, ‘odd’ questions. For relevance, we grade each question on a scale from 0 to 5, 0 being irrelevant to the issue of detection and attribution of 20th Century climate change, 5 being extremely relevant. For scientific content, we rate the reasonableness of the question posed (i.e. does it make any sense at all), from A to F (A being a very well posed question, F making no sense). For sources, we generally point to a paper or discussion that addresses the real issue.
- From the distribution of the vines, olives, citrus and grain crops in Europe, UK and Greenland, calculate the temperature in the Roman and Medieval Warmings and the required atmospheric CO2 content at sea level to drive such warmings. What are the errors in your calculation? Reconcile your calculations with at least five atmospheric CO2 proxies. Show all calculations and justify all assumptions.
- Relevance: 0 – poor. Basic logical fallacy. The existence of prior warm periods that may have been caused by different effects (such as solar changes, orbital variation, continental configuration etc.) does not imply that the human-caused increase in CO2 is not causing warming now.
- Scientific Content: D – phenology (the distribution and timing of species) can potentially be useful for tracking climate changes, but it is just one of many different types of proxy information available, and has it’s own regional, temporal, and seasonal limitations. Even more problematic, it is well known that the patterns of surface temperature variability during the “MWP” – more accurately, the Medieval Climate Anomaly (MCA) – and LIA periods were spatially quite heterogeneous, and a record at one or two locations generally tells us very little if anything about global patterns. Even a cursory examination of the relevant recent literature (for instance, Osborn and Briffa, 2006) reveals that the pattern of warmth during the Medieval era was far regional in nature, and does not approach the truly global scale of warmth evident in recent decades.
- Sources: Greater extent of vineyards today in England than in medieval times. Ice core records. Incoherence of the Medieval warm period.
- Relevance: 0 – pure misdirection.
- Scientific Content: F – We know what CO2 and CH4 levels have been over the last 15,000 years and they oscillated within about 10 ppmv (CO2) and 100 ppbv (CH4) of their Holocene values since the start of the current era – until the industrial period (around 1750) since when CO2 has increased by 35%, and methane concentrations have more than doubled. In each case the values being measured today are way higher than anything measured in 800,000 years of ice core records, and likely higher than anything since the Pliocene (~3 million years ago). The idea that bacterial methane production at 4km in the Earth’s crust has anything to with this is laughable.
- Sources: IPCC FAQ is all that is required. Do volcanoes produce more CO2 than human activity? Not even close.
- Relevance: 3 – clouds certainly have an effect on climate and understanding their variability is the subject of much research.
- Scientific Content: F – The question makes no sense. Clouds at 0% humidity? Is humidity supposed to be globally uniform? And where should these cloud changes occur? The change for low-level clouds will be of the opposite sign to changes in high level clouds, and changes in the Arctic will give different answers than changes in the tropics. It should go without saying that Plimer is mistakenly assuming that he has accurate information for global temperatures over 2000 years.
- Sources: Cloud Feedbacks in the Climate System.
- Relevance: 0 – completely irrelevant.
- Scientific Content: F – for those that don’t know ‘crack-seal deformation’ is a geologic process that causes the veins of crystals/minerals etc. in many rock types. (see here). Its relevance to atmospheric concentrations and isotopic composition is absolutely zero. It has no influence on atmospheric residence time – whether since 1850 or at any time in the past.
- Sources Discussions of the actual carbon cycle and the real influences upon it.
- Relevance: 0 – (again). The acknowledged climate changes in the past caused by natural events in no way implies that human effects are negligible today. Does the existence of forest fires caused by lightning imply that arson can never happen?
- Scientific Content: C – There is a lot of interesting science related to deep time, but any discussion of such changes must be prefaced with the acknowledgment that our knowledge of greenhouse gases, temperatures or any other potential forcing or response is very limited compared to what we know about climate today or even in the last ice age. Given that we don’t know precisely what CO2 levels were (let alone CH4, N2O, ozone, aerosols, ice sheet configurations, vegetation distribution etc.), the attributions of climate change at this distance is speculative at best.
- Sources: The faint young sun paradox.
- Relevance:1 – There are amplifying feedbacks between climate and CO2 – which are most evident in the long ice cores from Antarctica, but this argument is trivial to dismiss without any recourse to ocean current velocities etc.
- Scientific Content:D – You can calculate the change in CO2 per deg C global warming over long (multi-centennial) timescales from the ice age data – it’s roughly 100ppmv/5ºC = 20 ppmv/ºC. The increase in atmospheric CO2 in the last 200 years is now about 110ppmv, implying that any natural driver would have need to have been more than 5ºC natural warming in recent centuries. This would have been noticed by someone.
- Sources: None required.
- Relevance: 4 – aerosols are an important climate forcing, and their history through time (even in the 20th Century) are quite uncertain.
- Scientific Content: C – Calculating the impacts of aerosols is quite hard, first because we don’t have great records for their distribution through time and space, and secondly there are uncertainties in how the mix with each other and how they interact with clouds. Forcing estimates for the human-caused changes in aerosols over the 20th Century therefore have quite large uncertainties associated with them and are a principle reason why attempts to constrain climate sensitivity from the recent record along have not been very successful. Volcanic effects are however quite well characterised, and actually provide one of the many lines of evidence for why GCM simulations are reasonable since they get the right magnitude and character of the volcanic effects on climate. However, there is no evidence whatsoever for large changes in interstellar dust changes in recent millennia and trying to pin recent warming on that is really grasping at straws.
- Sources: Climate sensitivity and aerosol forcings.
- Relevance: 0 – again more misdirection. The throwing around of irrelevant geologic terms and undefined jargon is simply done in order to appear more knowledgeable than your interlocutor. The argument appears to that climate is changing due to tectonically slow changes the direct heat input from ocean sea floor spreading. This is absurd.
- Scientific Content: F.
- Sources: Definition of ‘flitch’.
- Relevance: 2 – pretty much irrelevant.
- Scientific Content: C – isostatic issues in sea level are important on long time scales, and there is still an effect today from the deglaciation 15000 years ago. It contributes a decease of about 0.3 mm/yr to the global sea level rise, compared to 3 mm/yr total (i.e. about 10%). If the idea was to imply that current sea level rise is simply the response to the deglaciation, then it was completely misleading.
- Sources: Reconciliation of the sea level rise, thermal expansion and ice melt.
- Relevance: 5 – the carbon cycle is actually a key issue.
- Scientific Content: A – understanding the carbon cycle given multiple constraints on the carbon fluxes (including some of the issues raised in the question) is important in showing that the ~35% rise in CO2 since ~1750 is in fact anthropogenic. This has been shown numerous times to be consistent with the known human emissions, increases in oceans and terrestrial carbon, the decrease in 14C content of the atmosphere, the decrease in 13C content in the atmosphere, the decrease in O2 in the atmosphere.
- Sources: Read the FAQ.
- Relevance: 4 – detection and attribution of climate change is an important issue.
- Scientific Content: B – First principles calculations of climate variability are most closely approximated by GCMs and multiple modelling groups have done various Holocene simulations. Attribution of any climate changes requires model simulations with and without each particular forcing and for the Holocene, this involves changes in the orbit, greenhouse gases, solar, meltwater regimes, ice sheet change, aerosols etc. and a comparison of the signature of the responses with patterns observed in the real world. However, comparable data to 20th Century sea levels or temperature changes are not available going back to the beginning of the Holocene.
- Sources: Attribution of mid-Holocene hydrologic changes to orbital forcing. Attribution of patterns of cooling at 8.2 kya to drainage of Lake Agassiz. Attribution of pre-industrial variability over the last millennia to solar and volcanic forcing (IPCC Ch8, p680+).
- Relevance: 1 – irrelevant. Has nothing to do with current causes of species extinction nor sources of CO2.
- Scientific Content: D – insufficient data exist to infer atmospheric composition, nor the sources of any hypothesised fluxes. We think that it is likely that mass extinctions are probably bad for “planktonic and terrestrial life on Earth” with very little error.
- Sources: This is a good intro to the P/T extinction event which is fascinating even if mostly irrelevant to today.
- Relevance: 3 – radiative transfer is a key issue.
- Scientific Content: F – the question as it stands makes no sense. How can using fossil fuel emissions of CO2 allow you to calculate the impact of total H2O? And why only three wavelengths? You would need the whole atmosphere distribution of water (in all three phases and which doesn’t exist outside a model) in order to calculate the radiative fluxes, and a full GCM to calculate all the other fluxes that influence the temperature. If Plimer is actually alluding to the impact of the direct injection of water vapour into the atmosphere from the combustion of hydrocarbons, then this makes even less sense since the perturbation time for water vapour is measured in days (rather than decades to centuries for CO2) and the relative importance of anthropogenic fluxes is much much less.
- Sources: Importance of water vapour and clouds compared to CO2 for the total greenhouse effect (roughly, 50%, 25% and 20% once overlaps are apportioned). Complete irrelevance of anthropogenic addition of H2O. Calculation of radiative forcing for anthropogenic CO2.
In summary, the relevance of these questions is extremely low, and even when the basic question deals with an issue that is relevant, the question itself is usually nonsensical and presupposes many assumptions that are certainly not a given (at least in the real world). In fact, for the couple of cases where the scientific content is high, the answer is in contradiction to Plimer’s unstated assumptions. The most obvious use of these questions to support a ‘we don’t know everything, so we must know nothing’ type of argument, which is a classic contrarian trope, and one that is easily dealt with.
These questions have as much to do with a debate on human caused climate change as tribbles have to do with astrobiology. Both are troubling, but for very different reasons.