Extreme weather
Climate change was the largest elephant in the room during the three US presidential debates – an evasion made all the more culpable by the devastation of New York City by superstorm Sandy soon after. Politicians and the media have been blamed for its absence from public debate, but the excessive caution of most scientists, unwilling to attribute even a part of the causation of specific extreme events to climate change, is a major contributor.
Arguably, there may be a game-changer in the important using new data (). These clearly link the frequency and intensity of storm surges in the US since the 1920s to warmer weather, as you briefly reported (20 October, p 4). As a minority of climate scientists, including Dim Coumou, James Hansen, Stefan Rahmstorf and Kevin Trenberth, insist, the time has now come to speak up wherever the evidence points to a probable connection between anthropogenic climate change and extreme, disastrous events.
• We do speak up about extreme weather that can be securely attributed to climate change – for example, on 7 July, p 5 and in this issue (“Climate downgrade: Extreme weather“) – but it remains difficult, though not impossible, to say how individual events are influenced by climate change.
Shaky ground
Thank you for pointing out that the recent conviction of the Italian seismologists was not about the failure to predict the L’Aquila earthquake in 2009, but rather about poor risk communication, and was built on an accusation of giving out “inexact, incomplete and contradictory information” (27 October, p 3).
It does seem unfortunate that these scientists are facing six-year jail terms. If giving out inexact, incomplete and contradictory information stands as a basis for their imprisonment, then this may set a precedent for others, including meteorologists working in weather forecasting, executives involved in the 2008 financial crisis, and various political leaders.
Life and death
I agree with Shelly Kagan that fear of being dead is irrational (20 October, p 42). But there is more to the fear of the process of dying than he admits to.
Will I die alone? With dignity? The law will not allow me to make arrangements with my carers (if any) to help me to die when life becomes insupportable, nor may I stockpile drugs to facilitate my own departure or that of my wife.
Suicide was a glaring omission from your recent special issue on death. The World Health Organization ranks it as the 13th most common cause of human death. Although other animals show some understanding of death, we are the only species to self-terminate a healthy body just because we don’t like how our life turned out.
Clearly suicide ends any possibility of reproduction so, if the principles of natural selection still apply to Homo sapiens, then suicide must be conferring some advantage on the species as a whole.
Dick Teresi’s piece reads as if brain-death testing was devised for the benefit of the transplant community (20 October, p 36). This is not the case. It came about in the early days of life-support technology, which yielded a small population of deeply comatose patients who were unable to breathe on their own. Within a few days of “life support” their hearts would stop beating. The tests now applied to such patients grew out of the need to develop robust evidence to justify withdrawal of clearly defined futile treatment.
The article can only add further confusion to what is already a vexed and complex issue. For instance, the movements Teresi described are due to lingering spinal reflexes and have nothing to do with the brain. This is routinely made clear to relatives visiting the intensive care unit.
I am concerned that this article may prove disquieting to the bereaved who have granted permission for organ donation, sowing needless doubt and discouraging people from signing up to organ donor registers.
Many people in the transplant community recall the effect of a BBC Panorama programme entitled “Are the donors really dead?”. In the four weeks following its transmission in October 1980, kidney transplants fell by a quarter. The programme was subsequently discredited.
Saffron Walden, Essex, UK
Political landslide
The goal of gathering data on landslides is to reduce deaths, says Dave Petley (20 October, p 26). While mountaineering in Peru in 1962, I saw a massive vertical slab of rock being undermined by Glacier 511. It could have fallen at any moment, causing a landslide that would obliterate a village.
Our report earned us a front-page headline – translated as “Dantean Slide Threatens Yungay” – in the national newspaper , and a government order to retract it or go to prison. We fled the country.
Eight years later the rock did fall, and the resulting landslide entombed 20,000. Data-gathering is effective only if combined with political expertise.
How much is time?
In Vlatko Vedral’s excellent essay suggesting that an ultimate theory might emerge from thermodynamics (13 October, p 32), he recalls Max Planck describing his idea that energy comes in discrete chunks as an “act of desperation”. Planck also anticipated Vedral’s argument.
In a 1909 lecture entitled “The Atomic Theory of Matter”, Planck discussed reconciling the observation that “the micro-changes of state are reversible” with the observation that “the macro-changes of states are irreversible”. He posed the question: “How many atoms are at least necessary in order that a process may be considered irreversible?” He answered it: “So many atoms that one may form from them definite mean values which define the state in a macroscopic sense.”
So the arrow of time applies to ensembles containing enough atoms that an average state is meaningful: which is to say when thermodynamic calculations can be done. That makes it easier to understand the paradoxical consequences of energy that comes in discrete chunks, such as the difference between the future, with its particles in multiple possible states, and the past, with its ensembles in singular states.
At last, a rational approach to physics. No multidimensional flights of fancy for Vlatko Vedral. No mathematically beautiful symmetry. Things are as they are because energy only flows from hot to cold, not from cold to hot.
• Oops. We misspelled the last name of Vlatko Vedral when we were reporting David Deutsch’s theory of everything last week (10 November, p 5).
Tape care
People handling tapes and cassettes tend to place them down flat. In my experience, data stored in this way is unreadable after just six weeks as the lower edge of the tape becomes deformed. If huge amounts of data are to be accumulated on tape (20 October, p 20) there must be a strict protocol to ensure correct storage.
You report that “Current projections by the trade body Information Storage Industry Consortium show that although hard drives will be able to store 3 terabytes apiece in a decade’s time…” Next to my desk is a trolley of 3-terabyte drives and a box of 4-TB drives: we’ve been selling them all year. Therefore I am writing this from the future. Now, the lottery results for 2017…
Portsmouth, Hampshire, UK
• IBM clarifies that this referred to hard drives that would be needed to build a data store for the Square Kilometre Array today, not in 2024. Apologies for the error.
Light fantastic
We all know that wind farms benefit the environment, but it is less well known that they can produce a nocebo effect: people predisposed to dislike them experience adverse health effects due to their proximity. Kay Siddell (27 October, p 28) finds their motion so disturbing that she keeps her curtains closed and takes vitamin D to compensate for the lack of sunlight.
Happily, information alone should be able to “cure” this adverse health effect.
As very little ultraviolet light of the wavelength necessary to stimulate vitamin D production can get through glass, closing the curtains will have virtually no effect on the amount of vitamin D her body produces indoors.
Bucolic agribot
James Mitchell Crowe reports that agricultural weeding robots will be able to reduce chemical use by up to 80 per cent, by identifying the leaves of weeds and applying microdots of weedkiller to them (27 October, p 42). He also tells us that other options are applying flame guns and lasers to burn the weeds.
Let’s hope that this is just a step towards reducing chemical use by 100 per cent, by training the robots to pull up the weeds or separate them from their roots with a hoe. Of course, they will need to be fuelled with a pint of cider at lunchtime.
Demon-slaying
I am sure that US physicist Charles Bennett had a very sophisticated way of dismissing Maxwell’s Demon (13 October, p 32). But I still enjoy the rationale given by my professor, F.C. Tompkins of Imperial College London: “The demon must eat to do the work, eating is essentially converting glucose to CO2 and H2O plus heat, and that, gentlemen [he always ignored the two women in the chemistry class of 1957-1960], generates entropy: QED.”