True value of clean rivers is far bigger than we think
You say that 拢870 million a year is the supposed beneficial impact on the UK’s health thanks to rivers and lakes encouraging physical activity and relaxation. I wonder if there is another, hidden cost that should be added in due to polluted waters(Leader, 18 February).
Back in 1995, I swam in a river downstream of a treatment works in Devon that pumps raw sewage into the water. The resultant ear infection caused tinnitus and hearing loss. I received many years of treatment from the National Health Service that has probably cost it tens of thousands of pounds.
Lunar dust sunshield may do more harm than good
Your story on using moon dust to create a sunshield for Earth implies that the 1 million tonnes of dust needed would have to be replaced at the rate of 200,000 tonnes a day. While you mention the possible use of a railgun to propel the dust into space, there would need to be infrastructure for other aspects of this(18 February, p 18).
Presumably, actual dust sources would soon be exhausted, and so machinery to mine and crush 200,000 tonnes of moon rock a day would be needed. All of this must be built and transported to the moon, probably within a few decades. Has anyone calculated the carbon footprint of doing this?
Let's look for evidence of interstellar shift on Earth
“Into the void” suggests we may risk an increase in cosmic rays as our planet passes into a new area of interstellar space in about 2000 years. We entered the area we are currently in around 60,000 years ago. I suggest calculating when previous transitions occurred to see if they tally with events in Earth’s history(18 February, p 38).
Old tech may be just what the climate crisis needs (1)
I was glad to see Mark Jacobson rectifying some of the overblown optimism around carbon capture and storage, direct air capture, “blue hydrogen” and so on(18 February, p 27).
He didn’t mention electrification of vehicles, but there are significant problems with this as well, on a global scale. I think these downsides should be weighed against the problems with biofuels, which are the most convenient alternative to petrol and diesel fuel and are really needed for aviation.
Also, there is another way to remove carbon dioxide from the air that doesn’t need new technology, just incentives and organisation 鈥� namely, storing biomass so that it doesn’t rot and return carbon to the atmosphere.
Old tech may be just what the climate crisis needs (2)
Jacobson makes the point that we will only achieve our climate goals on the short timescales necessary if we use existing technologies. I and most people would agree. Unfortunately, he then includes a yet-to-be developed technology as one of the solutions. Storage for renewables, despite what he says, is nowhere near ready to help support solar and wind to any meaningful extent. He also says that uranium will run out. It won’t, at least not during the period that would be needed to bridge the gap to future technologies.
Remember, kimchi isn't the only fermented food
We hear more and more about fermented foods and how good they are for our microbiome and hence our immune system. But it is frustrating to always hear kimchi given as the example(4 February, p 41).
What about our centuries-old European tradition of fermenting cabbage or root vegetables to provide nutrients and, above all, vitamin C over the winter. Often served with spicy sausage or as a soup, such ferments are called choucroute in French and sauerkraut in German.
Let's turn the wood wide web on its head
You report doubts about the “wood wide web”, in which trees communicate and share resources via buried fungi. I think it is more likely that the fungi are in charge, actively encouraging certain types of tree to grow in certain spots. The fungi could favour mixed woodland species and discourage monocultures(18 February, p 10). Could a mature forest be the garden of fungi?
On the hope that climate extremes are unlikely
Is a 4掳C temperature rise by 2100 ruled out? Graham Lawton assures us that the current models say so. However, I wonder if there is an assumption that climate feedbacks will be constrained. The models don’t include release of methane from permafrost at the observed and rapidly rising level. In the past few years, anthropogenic methane emissions haven’t been rising a lot, but the (14 January, p 28).
Worriers, resolve to go fretless for Lent!
Kayt Sukel reports on people scheduling set periods when they are allowed to worry as a way of managing and reducing paranoia. I suggested another approach to someone, that they give up worrying for Lent, as they were always fretting about something. They felt so much better that they did this every year(11 February, p 42).
All hail energy saving, now let's look at water
I thoroughly enjoyed reading your feature on the 2000-watt energy-saving challenge(11 February, p 36).
We now need something similar for water consumption. There are few tools to track usage and not that much talk about it. Shouldn’t we give water use the attention it deserves, or, like energy, are we going to leave it until it is (almost) too late?
Floating eyes in the sky are really nothing new at all
I find it amazing that it has taken China and the US until now to think of spying on each other using flying objects. I suggest the outrage may be manufactured for immediate political ends(11 February, p 9).