Editor's pick: What are the barriers to climate action?
Thank you for your seven steps to save the planet (8 December 2018, p 31). I would have found it even more useful if it had contained a list of the barriers to achieving each step and how we might overcome them. Barriers to killing oil, gas and coal, for a start, include entrenched fossil fuel interests and their disproportionate influence over elected representatives.
Strengthening democracy through more robust lobbying and campaign finance laws, and ensuring that control of the media isn't centralised could help. So could making sure that your retirement plan isn't investing in fossil fuels. Shareholder activism can make a lot more difference than reducing your personal emissions.
Why not join a political party or, if you are more daring, get involved in to try to change the political landscape? When you can, challenge the idea that economic growth is a good thing. The barriers to saving the planet have a lot more to do with the sanctity of capitalism and the compromising of our democracies than our inefficient, old fridges.
Uncertainty over climate looks self-imposed
Michael Le Page deals with the confusion over climate change figures (15 December 2018, p 34). This seems self-imposed.
The one thing that seems certain is that more carbon dioxide means more warming. I have looked on in disbelief for 40 years as arguments have raged over the precise degree of temperature rise, mired in incomplete understanding of all possible factors, feedbacks and time lags. Can it be that actual CO2 levels, which are measurable in real time anywhere on the planet and whose historical values are known from extensive agreed records, are downplayed by corporate powermongers to whom they offer no room for filibuster?
A target of 400 parts per million of CO2 would have been realistic in 1980. A target of 450ppm now could take us to the brink of no return, but it would give a firm upper limit to permissible carbon emissions.
First class post 鈥� 12 January 2019
Weird: ignore the young’s need for education but take blood to keep us old folk alive
Rosie Evans in response to a plan to use young people’s blood to treat Parkinson’s (5 January, p 6)
The question on climate taxes is: who pays?
Olive Heffernan says that leaders such as President Macron of France need to find some backbone, confronted with climate change and the ‘gilets jaunes‘ opposition to his tax rises (15 December 2018, p 26).
But why did Macron start by taxing the transport that the least well-off depend on? Surely it would be sensible to start by taxing those who are rich? For example, Lewis Hamilton is believed to be the richest UK-born sportsperson. He is to rent a £16.5 million private jet from his own Isle of Man company to receive a refund of £3.3 million in value added tax.
This may be legal, but why does he deserve a tax handout for his personal transport while lesser mortals get a tax increase? We all share the same planet.
Fingers in and out of Stone Age cave art (1)
Your piece on the handprints of the prehistoric artists of Gargas and Cosquer caves offered several possible explanations for the missing digits (8 December 2018, p 16). None of these reflected my experience when teaching young schoolchildren to paint their own cave animals. While painting with their right hand, several children held a spare brush or other tool in their left hand, leaning on the wall, with the fingers of that paint-covered hand bent around the brushes. This left handprints with missing digits, without requiring any frostbite, nor screams of amputation, ritual or otherwise.
Fingers in and out of Stone Age cave art (2)
Michael Marshall discusses hypotheses on absent fingers in Stone Age cave art. Perhaps there is a simpler explanation.
The ubiquitous practice of flint-knapping would have resulted in many injured and infected fingers. Rather than risk blood poisoning or gangrene, those with severely damaged digits could have amputated them with a newly knapped tool. So before Occam had a razor, there may have been a flint knife.
Ways of navigating and orienting ourselves (1)
Emma Young discusses styles of navigation (15 December 2018, p 38). As a teenager in the southern hemisphere, I learned to find north using a watch and the sun. I trained as a meteorologist in the days when students went outside to do field experiments.
When I first visited the northern hemisphere, it became clear how much I subconsciously use the sun to gauge approximate time and points of the compass, because I had to consciously readjust these assessments. Many friends who didn’t get my training don’t use these cues in navigation or for a sense of direction.
It seems there is a significant component of learned skill in sense of direction, as the article suggests, although I am not sure whether or not this helps when navigating at night.
Ways of navigating and orienting ourselves (2)
Young reports Kate Jeffery using the direction of shadows as an aid to orienting herself when navigating. Satellite dishes on houses are also useful. In the northern hemisphere, they point south at satellites in geostationary orbit over the equator.
Meal kits come with attached diesel vans
Chelsea Whyte weighs up the pros and cons of meal kits (8 December 2018, p 22). She does not mention one quite significant drawback: the transport costs of getting these kits to people's houses. Presumably most are delivered in small or medium, diesel-fuelled vans. Many of these will be nearly empty, especially when a service is new. Most will be in urban areas that are likely to already have traffic congestion and air pollution problems. So is this not just compounding the increasing contribution of online shopping in general to these issues?
The many lives of washable nappies
Alice Klein highlights a study suggesting little difference between the environmental footprints of washable and disposable nappies (24 November 2018, p 22). I suspect this underestimated the average journey of a washable nappy and the commitment of those who use them. In the 1960s, my mother used terry nappies with my brother and later with me. Then, for decades, my father used them as cleaning cloths.
After becoming a parent, I made sure our fabric nappies were passed on to a like-minded parent who said they would have a third life with another family. Who knows, maybe they will have a fourth life as rags.
But how much power does this thing produce?
You say that a hygroelectric generator based on graphene produces 1.5 volts and that this is equivalent to an AA or AAA battery (1 December 2018, p 20). But I want to know what current it delivers, and so its power in watts.
The editor writes:
• The experimental device – and an AA cell . What was interesting was that it was possible at all.
Richard Pearse's claim to a New Zealand first flight
Douglas Heaven reports that a prototype aeroplane using electroaerodynamic propulsion flew for 12 seconds, the same as the Wright brothers achieved with their maiden flight (24 November 2018, p 7). It is a historical fact that the Wright brothers flew their bird-like monoplane on 17 December 1903. But many believe that was the , as early as 31 March 1902, before the Wright brothers.
Later, witnesses reported that Pearse flew 400 metres and soft-landed on a hedge on his Timaru farm. His aircraft was also the first to use proper ailerons, instead of the inferior warping system that the Wrights used.
Twinkle, twinkle, little energy-saving bulb
Alice Klein and Chelsea Whyte say that switching Christmas lights to static rather than flashing mode uses less power (1 December 2018, p 22). This is true of incandescent lights, which draw high “inrush” current when the filaments are cold and have low resistance. But LED lights have no comparable phenomenon. Their energy use is strictly proportional to the percentage of “on” time. If they are on only half the time, they use half the energy of static lights.
Incandescent lights that twinkle individually waste further energy because they use thermal timers in each bulb. Current passing through a bimetallic strip causes it to bend as it heats up, breaking the circuit until it cools down to repeat the cycle. LEDs can twinkle using solid-state timers that use negligible energy.
All creatures great and small, and evolved
James Mitchell Crow gives a short description of some synthetic engineered life forms, currently being developed by Nina Pollak in Australia, that will look like juvenile jellyfish (8 December 2018, p 40). You called them .
They will be real creatures, in the original, historical sense of the word, as they will have a creator. In that sense, we are the pseudo-creatures because we evolved without requiring one.
For the record 鈥� 12 January 2019
鈥� When inhibitory cells were implanted into epileptic rats and then turned off, these rats had nearly as many seizures as those with no implants (22/29 December 2018, p 8).
鈥� It is rolling resistance in tyres that accounts for between 5 and 30 per cent of vehicles’ fuel consumption (8 December 2018, p 19).