Sunday, February 23, 2014
A letter in New Scientist (15 February 2014, p.34) prompted me to write this post, firstly because the use of the word 'poo' gets up my nose (when my children were young, we as a family, used the word shit) and secondly because of Stuart Tallack's aforementioned letter. Since it is not preserved in the magazine's online archive, I reproduce part of it here. Indeed, it could have been written by me:
I am not 5 years old and so don't need the prissy and childish word "poo" to assault my eyes. Excreta, faeces or droppings are perfectly acceptable; dung is perhaps not, as it implies manure. Shit was originally used without any connotation of vulgarity and should re-enter respectable society. But please, not "poo". What next? Articles on genitalia using such euphemisms as "front bottom", "naughty bits" and "meat and two veg"?
Thank you, Stuart! It needed saying. Now I'm off for a shit... and maybe I'll read one of my favourite Pooh stories while I sit on the bog (throne, john etc.). Got that?
Tuesday, February 26, 2013
|Prototype for the Integral Fast Reactor|
Yet there is a solution available: PRISM reactors, based on the proven passively-safe Integral Fast Reactor. These can 'burn' plutonium (the UK has 100 tonnes), actinides, and depleted uranium (UK has 35,000 tonnes). IFRs are highly efficient and versatile, burning almost all their fuel. By contrast, a Light Water Reactor (e.g. Sizewell B) uses 0.65 per cent of the energy in the original uranium ore resulting in the radioactive waste, currently such a headache. The waste produced by IFRs is about 1/20th of that from an LWR. Its radioactivity within 200 years is about the same as mined uranium ore so no long-term repository is necessary.
David MacKay, chief scientist at the Department of Energy and Climate Change, says that there is enough energy in the UK's waste stockpile to power the country for more than 500 years. So why are we still obsessed with repositories? Why not use the 'waste' to make vast amounts of carbon-free electricity, simultaneously destroying almost all the 'nasties'?
Friday, January 25, 2013
I have been growing organic fruit and vegetables on and off in several different countries in the world all my life, albeit in a small way. For the last 12 years, my wife and I have been growing commercially for a small box scheme, certified by the Soil Association (one of the several UK organic licensing bodies). In the 1990s, I was heavily involved in the anti-GM movement, helping organise protests, demonstrations, writing to the press and the supermarkets. I even went on the radio once and had a rant about Monsanto and the big corporations. I also started a website for kids which began with an illustrated guide to genetic engineering. (It's still there now – joined by another seven guides to issues which will be of great importance to the kids who are going to inherit our rather damaged world).
But as the years have passed and as it has become abundantly clear that people are not dying in droves because of GM, I've changed my mind. The famous economist John Maynard Keynes is alleged to have said to a critic who accused him of a U-turn, "When the facts change, I change my mind. What do you do, sir?" I am a scientist by training and so I constantly question and revise my views according to the evidence available. Sadly, the organic movement and other mainstream 'green' organisations remain as intransigent as ever in their views on genetic engineering: they seem to be stuck in a time warp 30 years out of date. Perhaps they, like politicians, don't wish to be seen performing a U-turn despite good reasons for doing so.
Basically, I don't understand why certain types of GM crops can't be approved for use with organic systems. It's hard enough growing organically as it is without constantly shooting yourself in the foot by refusing to move with the times. Let's just take one example. Last year, potato blight struck early in the soggy, damp non-summer. The result was that my potato crop was about a quarter of what it normally is. Yet there is a blight resistant GM potato which has been developed in the public domain. If only I could have used that! But I can't because it's against the organic regulations and even if I wasn't organic, I still wouldn't be able to use it because of all the 'green' protests which have made sure that it never sees the light of day; not for organic growers nor for any conventional growers.
What's so terrible about this potato? Is it Frankenfood? No, it's just an ordinary potato with one gene inserted from a wild potato which happens to show resistance to the dreaded Phytophthera infestans, the fungal late blight which caused the Irish potato famine in the 1840s when over a million people died of starvation. Alarmingly the fungus has begun to reproduce sexually over recent years which makes it much more virulent. It had previously reproduced itself asexually and was relatively easily controlled by spraying fungicides or growing somewhat resistant potato varieties.
So why not embrace this GM potato? The introduced gene comes from the same genus - Solanum - and so is not even transgenic. Why is this potato 'bad' whereas the blight resistant Sárpo potato, bred over many years by conventional means, is good? (I was growing a Sárpo variety and it succumbed to the blight like the others.) Of course, blight resistant GM potatoes, like the Sárpo varieties, will sooner or later be overcome by P. infestans. It's an arms race and this is where GM potatoes can leap ahead because it only takes a year or two to splice blight resistance into the genome and grow the resulting plant. It took the Sarvari family, who developed the Sárpo potatoes, some 40 years of careful selection of resistance traits to produce truly blight resistant varieties. As Pamela Ronald, Professor of Plant Pathology and Chair of the Plant Genomics Program at the University of California, Davis says: "To meet the appetites of the world's population without drastically hurting the environment requires a visionary new approach: combining genetic engineering and organic farming". She and her husband co-authored 'Tomorrow's Table' which, argues Stewart Brand, makes "a persuasive case that, far from contradictory, the merging of genetic engineering and organic farming offers our best shot at truly sustainable agriculture".
I agree. It seems to me that organic farming regulations are throwing the baby out with the bathwater. Of course there's 'bad' GM where the profit motive comes before anything else. That was the origin of RoundupReady soybeans, a first generation GM seed which locked farmers into buying Monsanto's brand of glyphosate herbicide. But there's plenty of publicly-funded GM research which is not-for-profit and genuinely attempting to help all farmers grow food crops which don't require multiple applications of 'chemicals' (conventionally-grown potatoes may need 15 applications of fungicide per year). It is an indication of the success of the 'green' anti-GM movement that nothing GM can be grown in Europe.
I think organic regulations should include carefully-chosen GM varieties, each selected on its merits, properly trialled (and not trashed) and tested. That way, organic growers could lead the way forward to a more sustainable agricultural system which can dispense with many 'chemicals' and give good yields under difficult conditions such as those we experience in 'summer' 2012.
Then there's modifying C3 plants like rice to adopt the more efficient C4 photosynthesis. Why is that not acceptable? It will produce far more rice on the same amount of land. And sooner of later, GM is going to make it possible for non-leguminous major crop plants to form nitrogen-fixing symbioses with Rhizobia bacteria. This would make a huge impact on staple crops such as the grass family (wheat, maize, rice) which provide more than half of all calories eaten by humans. It would counteract the synthetic nitrogen overload which is seriously affecting one of the nine planetary boundaries. Would the anti-GM protesters still trash any trials? Shouldn't organic regulations embrace such development? Properly regulated and monitored, genetic engineering is an incredibly useful tool which could and should be available for all growers. Why not use it?
Tuesday, March 15, 2011
Double damage: This is a double disaster, firstly to Japan and its people (the horrifying drama is still unfolding as I write), and secondly to plans to increase nuclear electricity generation worldwide. Nuclear power is essentially carbon-free and without it, there would be a huge increase in coal-powered generation. Coal is the most polluting of fossil fuels: 1 ton of coal burned produces around 2.8 tons of CO2.
Lessons learned the hard way: What lessons can we learn from Fukushima and earlier nuclear disasters like Chernobyl?
- never build reactors near earthquake-prone plate boundaries
- never build them in coastal districts known to be vulnerable to tsunamis or rising sealevels
- build them with robust containment which can withstand hydrogen explosions, wartime enemy action, aircraft crashes
- don't use nuclear fuels which create dangerous and long-lived radioactive waste
But supposing there was a way to have our nuclear cake and to eat it. A way which is truly safe and within our grasp right now. There are two fundamental changes which the nuclear industry can adopt to make future nuclear power safe and acceptable. One is a change of fuel and the other a change of containment:
- stop using uranium/MOX fuels and replace with thorium: no meltdowns, no bomb-making potential, no enrichment needed, radioactive waste short lived. Thorium reactors were abandoned early on by the nuclear industry during the Cold War because they could not be used for making nuclear weapons (which need enriched U-235 and plutonium)
- the containment problem, illustrated horrifically by the Fukushima reactors, can be solved by building all future reactors deep underground. Each reactor should have a large water store above it for passive emergency cooling, employing gravity and not pumps (which failed at Fukushima). The undergound installation, at the end of its design life, can be decommissioned by sealing it complete with its complement of spent thorium fuel whose radioactivity declines in tens of years rather than thousands.
Suddenly, thorium-fuelled reactors underground look like a technology which, unlike fusion power, is ready and waiting in the wings. Its time has come. How can we make it happen?
For more on thorium reactors, see Greener Than A Thousand Suns and Liquid Fluoride Thorium Reactors.
Monday, December 21, 2009
Business as usual.
(But it's still the planet, stupid).
To cheer yourself up, listen to The Now Show's interpretation of what went wrong. Happy Solstice!
Tuesday, October 20, 2009
The answer, of course, is the wind turbine. This particular turbine should generate enough electricity in an a year to save more than 7 tonnes of CO2.
The SUV doesn't need planning permission to buy; just a lot of money. Much more than the turbine. It will generate more CO2 each year than the turbine will save. It will also cost much more to buy and to run.
Revised question: which of the above machines should have planning permission before you can buy and use it?
It's a no-brainer and a good example of the cockeyed system we have to change in order to tackle the planet's climate woes and overconsumption. As you might guess, I am in the throes of trying to get planning permission for installing a 6kW turbine on my farm.
Tuesday, September 01, 2009
'Climate is an angry beast...' Quote by climate scientist Wallace Broecker
Image by Lisa Brewster
Everyone’s heard that the planet’s climate is changing but is it true that the planet is warming? What’s the evidence? If there’s an unusually cold winter, isn’t that evidence of global cooling? Many people are sceptical and a little confused. Is global warming just another scare story put about by green eco-nutters? It’s more comforting to believe that everything’s fine and we can carry on as usual. But an unpalatable truth is that the global economic system depends almost totally on cheap fossil fuels – coal, oil, natural gas – to power industry, transport, modern consumerist lifestyles and provide employment. Taking action to reduce the greenhouse gases (GHGs) - which science says cause climate change - will mean drastically cutting back on using these fuels. There’s trouble ahead. So it is reasonable to question how we know climate change really is happening. Mitigation and adaptation will dramatically change our lifestyles, though not necessarily for the worse. So what really is the evidence for climate change? This 4-minute guide summarises it.
Climate and the weather: There is now a mass of evidence that climate is changing fast. Confusion arises because most people don’t appreciate the difference between weather and climate. A cold winter in north Europe doesn’t mean that the climate is cooling: there’s a lot of natural variation year by year and always has been. Climate is about averaging the weather’s variations around the planet over a number of years and looking for a global trend. And there is a trend: temperatures are increasing. The planet is getting hotter and the rate looks set to accelerate.
The evidence comes from careful observations by scientists from many different disciplines over many years. Many lines of evidence can actually be seen happening:
- Ice sheets and glaciers are melting everywhere and there are many dramatic before and after photos which illustrate this
- The area covered by floating sea ice in the Arctic is reducing rapidly
- Permafrost in the Arctic is melting, releasing methane, a potent greenhouse gas (an example of a dangerous ‘positive’ feedback)
- The lower atmosphere (troposphere) is becoming warmer
- Sea levels and ocean temperatures are rising (see below)
- Species of animals and plants are ‘migrating’ to higher latitudes because their home ranges are becoming too warm for them. Diseases are also expanding their range and affecting crops and trees as well as people
- Coral reefs are being killed by the hotter waters. Corals are not only beautiful to look at, they are nursery grounds to myriads of marine species (and sometimes called ‘the rainforests of the sea’.) The planet needs its corals because they sequester carbon from carbon dioxide (CO2) to build their skeletons out of a hard, white mineral called calcium carbonate so, like trees, they are ‘carbon sinks’
- The oceans are absorbing much of the CO2 but as they do so, they are becoming more acidic. This is affecting all kinds of marine life which build their shells out of calcium carbonate. The mineral dissolves in weak acid so acidification means that corals and shells won’t be able to grow, triggering all kinds of knock-on effects in the marine food chain.
Predicting the future: Global Climate Models Climate scientists have developed computer models to predict future climate. They know these are generally accurate because they can successfully be used to predict known past climate by checking their predictions against actual observations (see below). The models allow scientists to predict how the climate will change over the next few decades and are a cornerstone of periodic updates from the Intergovernmental Panel on Climate Change (IPCC) on global climate change.
How can scientists investigate past climates accurately? One way is to examine drill cores taken from ice sheets like those covering Antarctica and Greenland. Past climates can be reconstructed effectively using the records of former atmosphere composition and precipitation preserved in the ice. What’s more, they can be cross-checked using actual historical records and other ‘proxy’ observations such as tree-rings, isotope analysis and radiometric dating. Importantly, the ice cores contain a record of CO2 levels which are higher now than at any time in the last 700,000 years. One well-known result of using all these different methods to assess past climates is the hockey stick graph in which numerous different lines of evidence broadly agree that temperatures have over recent decades started on a steep upward trend. It is not a uniform upward movement because of complex atmosphere-ocean oscillations, the best-known of which is El Niño.
One prediction made by the computer models is that the Arctic and Antarctic will warm faster than the rest of the world. Evidence is coming in that not only is this happening but, alarmingly, it’s happening even faster than predicted because of positive feedbacks. Other predictions show droughts and desert areas increasing (particularly in Australia) and more violent weather patterns with poor countries particularly vulnerable (especially much of Africa). Tropical forests - normally massive carbon 'sinks' (the trees absorb CO2 from the air and transform it into wood, so locking up the carbon) – are today being logged and burned to make way for farming and biofuel plantations, releasing vast quantities of CO2 into the air. As if that wasn’t enough, the models predict drying and major die-off of the Amazon rainforests and increase in wildfires in these former sanctuaries of biodiversity.
The main concern is that rising global temperatures will trigger ‘tipping points’ where GHG inputs reach a critical level, causing a major climate ‘flip’ which could be extremely hostile to much of life – including humans. We know from the distant past that major climate change events can and do occur. One of these, almost certainly caused by GHGs from stupendous volcanic eruptions, wiped out 90 per cent of life on the planet. This mass extinction event occurred around 250 million years ago and was probably worsened by ‘tipping points’ such as major methane releases from methane clathrates. (Today’s oceans host vast deposits of clathrates.) We know of 5 mass extinctions from the geological record and we are now causing the sixth.
How warming happens: the greenhouse effect If you enter a greenhouse on a sunny day, it’s hot because the sun’s heat is trapped by the glass. Carbon dioxide (and other gases like methane, nitrous oxide and ozone-killer CFCs) are called greenhouse gases because they, like the glass in a greenhouse, trap some of the sun’s heat. Without the greenhouse ‘blanket’, the planet would radiate most of this heat back into space. As more GHGs gush into the atmosphere from power station chimneys, farming and car tailpipes, it’s rather like adding double glazing to the greenhouse: more heat is trapped. Most of this heat is absorbed by the world’s oceans so they, like the air, are getting hotter.
The bathtub effect: Without the greenhouse effect, life on Earth wouldn’t exist. Some GHG are essential to keep the planet habitable, but humans are grossly overdoing it. Imagine a bath (which represents the atmosphere) with the taps full on and gushing water (representing GHGs pouring into the atmosphere). There’s no plug so water is also draining from the plughole (representing carbon ‘sinks’ like the oceans and forests which both naturally absorb CO2). In a stable system, the amount of water coming in is roughly balanced by the amount flowing out: the carbon cycle. But we’ve upset the system by pouring increasing amounts of ‘water’ into the ‘bathtub’ so the tub is filling up and will soon overflow. The ‘carbon sinks’ drain is overwhelmed so the planet heats up. This is well explained by the Bathtub simulator. Before people began to burn fossil-fuel in the 19th century, CO2 levels – even during warm periods - were below 300 parts per million (ppm). During ice ages, they fell to less than 200ppm. Since the industrial revolution, they have risen ever faster, particularly in the last decade and now stand at 387. Actual warming closely mirrors this rise.
Sea level rise: Warmer water expands so sea levels go up. But sea levels also rise because of all the melting glaciers and ice sheets around the world. In fact, the rapid melting of almost all the world’s glaciers is one of the most scary indicators that the climate is warming. Sea levels have been rising by about 2mm each year for the last century but this is predicted to greatly increase, causing large scale flooding of many low lying populated areas. The IPCC in their latest (2007) report predict about half a metre of further sea level rise though more recent research suggests double that amount.
This guide to the scientific evidence for climate change and the predictions science can make is deliberately very brief. It first appeared on OneClimate.net. Below is a list of sources of further information if you want to follow anything up.
The Royal Society has produced this overview of the current state of scientific understanding of climate change to help non-experts better understand some of the debates in this complex area of science.
New Scientist's guide to climate change, global warming and greenhouse gases with many other interesting links and news stories.
‘Understanding and Responding to Climate Change’ Downloadable PDF document from the US National Academies. Excellent guide with clear explanations and many images. A free printed version is also available.
RealClimate Climate science blog written by climate scientists with many useful short guides e.g. ‘Highlight’ (right column, scroll down)
Climate change for kids, explained by OneWorld’s Tiki the Penguin
OneWorld’s guide to climate change exposes the reality that global warming will impact poorer countries harder and sooner than the richer countries which are responsible.