Hard to swallow a 1.5掳C+ world as anything but bad
I was astonished by your comment article “Keeping our cool”. It is subtitled: “Despite pessimism, limiting global warming to well below 2掳C is within our grasp.”
The writer states: “And while ‘well below 2掳C’ is very much in reach, we are clear the tougher 1.5掳C goal no longer appears feasible… And a ‘well-below 2掳C’ world won’t be pretty, as social tipping points, including mass movement of people and conflict for resources as vast areas around the equator become effectively uninhabitable, strain global cohesion and economic and political stability.”
So avoiding 2掳C of warming is supposed to be good news? Exceeding 1.5掳C is the sort of catastrophic situation that climate scientists and others have warned of (2 December, p 21).
Extending lifespan may not be such a good thing
In media coverage on the topic of significantly extending human lifespans, there seems to be a general view that doing so would be an unalloyed good. But the most significant impact would be an increase in population. If we all lived an average of 12 per cent longer than at present, that would amount to another billion people, disproportionately older. I don’t see how this would be a good thing (2 December, p 9).
Best use for sunlight navigation device
I read with interest about the “insect-eye” compass that can navigate by the sun even on cloudy days. While I can see a use for it in drones, it is relatively easy to compensate for the magnetic fields drones generate, and hence conventional systems can work. Where it may come in handy is for manual or autonomous navigation at high latitudes where Earth’s magnetic field at the surface becomes closer to vertical and begins to give less and less information about horizontal direction (2 December, p 12).
Indeed, there is some (albeit disputed) evidence that early northern European navigators, such as the Vikings, used natural crystal polarisers to determine the direction of the sun when visibility was too poor for it to be seen.
This is why we must be wary of geoengineering
The study that found there is a weekend boost to plant productivity in Europe because of reduced air pollution by aerosols, which block sunlight, should be a warning to those who seek to address global heating by injecting aerosols into the atmosphere (25 November, p 11).
This research shows how sensitive plants are to any drop in sunlight. Addressing climate change through atmospheric geoengineering will reduce plant photosynthesis on land and at sea globally, with probably catastrophic impacts on nature and agriculture.
A passing star may yet wreak havoc on Earth
It is suggested that the orbits of planets in our system would probably be unaltered by a star passing at about 100 astronomical units from the sun. But what of the many Oort cloud and Kuiper belt objects? They would be much closer to the passing star and more easily disturbed (9 December, p 12). Could the planets expect a bombardment of comets and asteroids?
When rooks lined up to admire their reflections
Following on the discussion about animals that might recognise their own reflection: when a riding school near me installed mirrors in its outdoor arena, I saw how the local rooks lined up on the fence and spent a long time looking at their reflections. After observing them numerous times, I concluded they were using the mirrors for preening and admiring the results (and each others’ looks). Maybe that isn’t true self-awareness, but it seemed similar to human vanity (Letters, 2 December).
Go carefully when it comes to AI's wonder materials
The arrival of the GNoME artificial intelligence model to predict new inorganic crystal structures is indeed exciting. Its positive potential is justly lauded, having increased the number of known inorganic crystal structures from around 48,000 to over 2 million, with potential for making better batteries, solar panels, computer chips, alloys and more (2 December, p 8).
But there is a worrying quote in the story: “You know the structure might exist, but if you don’t know what it does, then it’s not clear whether to make it or not.” The history of new wonder materials is made up of huge benefits and some toxic disasters. This AI-driven leap in potential materials bears promise, but may also be the harbinger of disasters. We should devote as much research to assessing possible risks as to the possible benefits of new materials.
We need to know the true price of a cuppa
You highlight the need to clarify the true cost of products on various grounds. It struck me that one good example of where this is needed is for the tea we drink, because production can take place in impoverished places. If factories aren’t run to Western standards and a living wage isn’t paid, that keeps prices artificially low (2 December, p 40).
We use the labour of these workers, take their wealth and criminalise them when they come to Western nations wanting a share of it. We make our own immigrants by both waging war and paying unrealistic prices.
On the road to a car-free utopia
Recent correspondence ponders car culture and how to address it. Cheaper goods in more local shops, stopping motorised “school runs” and a culture of promoting (free!) public transport etc. would be far better than pushing even electric private vehicles (Letters, 2 December).
On the hunt for the oldest examples of art
Did any of the teams looking at “art” dating back millions of years include an artist? If art academics studied a million-year-old activity that resembled science without a scientist, we would laugh (18 November, p 32).