On the best route to decarbonising quickly (1)
Former UK government adviser Simon Sharpe is dismissive of carbon taxes as a means of tackling the climate crisis, instead urging investment “in new technologies and new systems” (30 September, p 37).
But these aren’t mutually exclusive. He himself says that we need “investment in targeted subsidies so that these solutions can take root while they are still more expensive than the fossil fuel alternatives”. That is the point of a carbon tax 鈥� to level the playing field by forcing fossil fuels to pay for their negative externalities.
And achieving that with a carbon tax is more even-handed than doing it with targeted subsidies: his approach needs central planning, choosing which new technologies merit subsidy and which don’t, whereas a carbon tax allows the free market to perform its magic much more efficiently. We don’t know enough to make such central-planning choices accurately.
On the best route to decarbonising quickly (2)
In his call to rethink how climate policy is communicated to policy-makers, Sharpe fails to mention the integrated assessment models (IAMs) that have underpinned Intergovernmental Panel on Climate Change reporting to governments for three decades. These are technology focused and highly dynamic. They track the unit cost of existing technologies against uptake, assess speculative technologies and contain detailed climate descriptions and stress mitigation. These IAMs include everything that Sharpe argues is missing from the net-zero debate.
Conversely, the risk-oriented formulation he advocates is more suited to eliciting adaptation. On the tough question he raises about individual carbon footprints, recent IAM studies show that climate-friendly lifestyles can radically ease the challenge of reaching net-zero by 2050. Individual actions can thus help derisk protecting the climate.
AI whodunnit had a fatal flaw
I agree that new AIs have shortcomings. When I asked ChatGPT to write a story in the style of Agatha Christie, it wrote pages of frighteningly realistic text until it broke the most basic rule of crime writing: it told me that it was the gardener who did it (7 October, p 20). The problem was, the gardener hadn’t previously appeared in the story!
Evolution could avert a future natural disaster (1)
You report on a study that predicts nearly all mammals will go extinct in 250 million years as continents recombine and the climate shifts (30 September, p 9).
However, I assume that the changes will occur so slowly as to allow considerable time for evolution. Humans may be long gone, but, as a last resort, many mammal species might adapt to spend a major part of their lives underground or in the oceans.
Evolution could avert a future natural disaster (2)
Researcher Alexander Farnsworth anticipates that, due to natural processes, atmospheric carbon dioxide will reach levels incompatible with mammalian survival in a quarter of a billion years. He hopes that “we’d be a space-faring civilisation by that point”. But the technical challenges in managing atmospheric CO2 levels are trivial compared with those of human interplanetary flight.
The UK just exported its industrial emissions
Concern over China’s carbon emissions misses a key point. In the 1950s, when vehicle use was really beginning to take off, British models were made from steel produced domestically and from locally mined iron ore and coal (7 October, p 12).
Now, the same car could be made from ore and coal mined in Australia then sent to China’s steel mills, with the steel sent to mainland Europe and turned into cars for export to the UK. We in the UK may pat ourselves on the back for cutting carbon emissions by closing our heavy industries, but we are responsible for the far greater emissions from the transnational production of modern cars, even though that carbon isn’t emitted here.
If a lack of free will is good enough for them… (1)
I offer further arguments against the existence of free will. First of all, two of the greatest minds to have ever lived, Bertrand Russell and Albert Einstein, scoffed at the very existence of free will (30 September, p 32).
Secondly, many parents of more than one child will attest to how different their offspring are and how their personalities stayed the same from toddler to adult. We must acknowledge Friedrich Nietzsche, who told us that we all become who we are. Free will is just wishful thinking.
If a lack of free will is good enough for them…(2)
Are the forces of evolution so powerful and compelling that they negate free will? Or are they so powerful and compelling that they create free will? Either you have no choice or you have no choice but to have choice.
Where are all the old 'how to write in code' guides?
Your fascinating article about deciphering historical documents written in code made me wonder where the code-breaking sources that must have been needed by the senders and recipients of these documents are (23 September, p 40). Have none been found? No worksheets where recipients struggled to “translate” what they were given? Are there no books with guidance on how to encrypt messages, or did each author invent their own method?
Welcome clarity on human microbiome
Thank you for putting aside the hyperbolic, catchy factoids on the gut microbiome to give clear comment. There are trillions of residents in our colons, but we are still in the very early stages of defining which microbial make-ups are better or worse (7 October, p 30).
Greater microbial diversity appears to be beneficial, and this is supported by diets with fibre, or prebiotics, from a variety of plant foods: fruits, vegetables, berries, wholegrains, legumes and pulses. Microbes consumed in foods, known as probiotics, don’t affect diversity in the colon, and the European Food Safety Authority hasn’t approved any health claims for probiotic products.