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First the link to this week’s complete list as HTML and as PDF.
Helen Czerski’s The Physics of Everyday Life is exceptionally cheap at only 11.24 € for the upcoming paperback. If it’s only half as good as Engel claims it is, it may make the ideal gift for less science oriented friends.
McDonnell’s way of paper writing is the one taught in most courses and exactly the one I see many fellow students struggle with. My own method is one I call
“concentrically from the inside out”. I start with whatever comes to mind first and whatever well-formed sentence comes to me under the shower and let it grow from there. This way the introduction naturally comes last, as it ought to. You can only introduce something well, if you know exactly what that is in the first place. The same goes for the conclusion. More than once that has changed for me, while carefully discussing the results in a well structured manner.
Just like so many others, Sands completely ignores the outcome of homoeostatic rebound. What she looks at is an instantaneous reaction to a short term unconscious exposure. From this she extrapolates to long term and consciously observed changes in circumstance. All human, and indeed biological, experience teaches us, that this kind of inference is (nearly) always wrong.
Early Neolithic societies are seen to have been essentially egalitarian, at least between households and families. (The structure inside the individual household is largely unknown as is the number of dependent household members.) This picture does not sit well with Karmin et al.’s male chromosome bottleneck implying a reproductive monopoly centred on a small number of male lineages.
On two counts Hands puts his conclusions stronger than they deserve to be. First he calls the deduction of temperature from oxygen isotopes well established. This is certainly true for isotopic enrichment and depletion. But that’s not what we measure. All we get are resulting absolute values. For the deduction of their enrichment we also need the ambient basic values they started from and these are not as well constrained over very long periods as we may wish for. Secondly all he has is a correlation. While from first principles and basic physics there can be no doubt about the warming effect of carbon dioxide, it rarely if ever was the independent driver of change. Mostly carbon dioxide concentration was itself an effect and acted as a positive feedback. The recent anthropogenic influence drives it in the opposite direction of its (currently downward) natural change. So while in the past the sun as driver and carbon dioxide as feedback acted in concert, the current rise is acting against the sun’s cooling trend. Any warming this results in has to be much weaker than the unicausal interpretation of past correlations suggests.
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