Category: People

Transit of Venus

This is a copy of a Post published on the 31st May to ensure that all who are interested get the details.

That Post was called, The noblest astronomy affords, all that follows is a copy of that Post.

Don’t miss the transit of Venus across the Sun.

Continue reading “Transit of Venus”

Congratulations, Ma’am.

A small tribute from two of Her Majesty’s subjects!

Best wishes for many years ahead as our Queen!

Jean and I managed to watch the hour-long tribute by Prince Charles to his mother’s wonderful Diamond Jubilee week-end.

Here’s a small extract of that programme that appeared on ITN News.

Then thanks to Martin Lack’s latest Post, I discovered that You Tube have the full programme as well.  Here it is – do watch it if you can, it is a lovely, personal and intimate reflection by Prince Charles.

At the end of the programme, both Jean and I felt very nostalgic about the long reign of Her Majesty Queen Elizabeth II.  However much we appreciate the life that we have here in Payson, Arizona, these two old Londoners still feel proud to be British.

There’s a great website here full of all the details of this very special time for Britain.

Finally, the extreme dry conditions of our forest mean that lighting a Jubilee Beacon here at home is out of the question.  The following is our alternative:

Beltane Fire Ritual, Edinburgh, Scotland

It’s what Jean and I do most Sunday evenings anyway!

The noblest astronomy affords

Don’t miss the transit of Venus across the Sun.

The full quotation is “This sight…is by far the noblest astronomy affords…” and was reputed to have been made by Sir Edmond Halley of Halley’s Comet fame, see here.  But today’s Post is about Venus.

Venus — Sister to Earth

From the NOAA Science on a Sphere website, we can read this about Venus,

Venus has been referred to as the sister or even twin to Earth by many because of its similar chemical composition, density and size. That, however, is where the similarities end. Venus is not only the hottest planet in the solar system, but also the brightest. Both of these characteristics are the result of the atmosphere that surrounds the planet, which is mainly composed of carbon dioxide and some sulfuric acid. This composition allows for the greenhouse effect to be astronomical causing the planet to have a constant temperature of 864°F. The planet is the brightest because the clouds, composed of sulfur dioxide and sulfuric acid, are highly reflective. The pressure of the atmosphere that surrounds Venus is 90 times that of the atmosphere around Earth, crushing any probes that land on Venus in a matter of hours.

Depending on where you live on Planet Earth you will see the transit on the 5th June, the 6th June or not at all!

Courtesy of Fred Espenak (NASA GSFC), who provides additional transit of Venus data from NASA.

(That additional data referred to above may be found here.)

That transit diagram plus mounds of other interesting stuff is on the Transit of Venus website and on that website this page has the details allowing you to work out what day and time the transit occurs depending on where you are.

To close let me be a little cheeky and reproduce, in full, what appeared on the Science Daily website on the 1st May.

Venus to Appear in Once-In-A-Lifetime Event

ScienceDaily (May 1, 2012) — On 5 and 6 June this year, millions of people around the world will be able to see Venus pass across the face of the Sun in what will be a once-in-a-lifetime experience.

It will take Venus about six hours to complete its transit, appearing as a small black dot on the Sun’s surface, in an event that will not happen again until 2117.

In this month’s Physics World, Jay M Pasachoff, an astronomer at Williams College, Massachusetts, explores the science behind Venus’s transit and gives an account of its fascinating history.

Transits of Venus occur only on the very rare occasions when Venus and Earth are in a line with the Sun. At other times Venus passes below or above the Sun because the two orbits are at a slight angle to each other. Transits occur in pairs separated by eight years, with the gap between pairs of transits alternating between 105.5 and 121.5 years — the last transit was in 2004.

Building on the original theories of Nicolaus Copernicus from 1543, scientists were able to predict and record the transits of both Mercury and Venus in the centuries that followed.

Johannes Kepler successfully predicted that both planets would transit the Sun in 1631, part of which was verified with Mercury’s transit of that year. But the first transit of Venus to actually be viewed was in 1639 — an event that had been predicted by the English astronomer Jeremiah Horrocks. He observed the transit in the village of Much Hoole in Lancashire — the only other person to see it being his correspondent, William Crabtree, in Manchester.

Later, in 1716, Edmond Halley proposed using a transit of Venus to predict the precise distance between Earth and the Sun, known as the astronomical unit. As a result, hundreds of expeditions were sent all over the world to observe the 1761 and 1769 transits. A young James Cook took the Endeavour to the island of Tahiti, where he successfully observed the transit at a site that is still called Point Venus.

Pasachoff expects the transit to confirm his team’s theory about the phenomenon called “the black-drop effect” — a strange, dark band linking Venus’s silhouette with the sky outside the Sun that appears for about a minute starting just as Venus first enters the solar disk.

Pasachoff and his colleagues will concentrate on observing Venus’s atmosphere as it appears when Venus is only half onto the solar disk. He also believes that observations of the transit will help astronomers who are looking for extrasolar planets orbiting stars other than the Sun.

“Doing so verifies that the techniques for studying events on and around other stars hold true in our own backyard.. In other words, by looking up close at transits in our solar system, we may be able to see subtle effects that can help exoplanet hunters explain what they are seeing when they view distant suns,” Pasachoff writes.

Not content with viewing this year’s transit from Earth, scientists in France will be using the Hubble Space Telescope to observe the effect of Venus’s transit very slightly darkening the Moon. Pasachoff and colleagues even hope to use Hubble to watch Venus passing in front of the Sun as seen from Jupiter — an event that will take place on 20 September this year — and will be using NASA’s Cassini spacecraft, which is orbiting Saturn, to see a transit of Venus from Saturn on 21 December.

“We are fortunate in that we are truly living in a golden period of planetary transits and it is one of which I hope astronomers can take full advantage,” he writes.

Editors note: Looking directly at the sun can cause severe and permanent eye damage. Do not look directly at Venus’ transit of the sun.

For more information see Wikipedia article.

Footnote:

I’m going to republish this in full on Monday, 4th June at the usual Learning from Dogs release time of 0700 UTC so to increase the odds of all my readers who would like to see the Transit having the information in good time!

Civilisations do fail!

Any lessons for today from the Valley of the Pyramids at Tucume in Peru?

The view of Huaca Larga (Photo: Heinz Plege/PromPerú)

Let’s set the scene,

It’s amazing to think that anyone lived here, that this valley was once green. Now it is sun-blasted, scorching hot, and the only life is the circling vultures and the rainbow-colored iguanas, like something out of a desert hallucination, skittering across the rocks.

The reminders of past life rise up around me, however, eroded to look more like drip castles than the pyramids they once were. I am in Túcume, the once-grand capital of the Sican culture, Peru’s mythical Valley of the Pyramids.

I am not far from Chiclayo, and even closer to the city of Lambayeque, where the Royal Tombs of Sipán Museum serves as one of the major tourist attractions on the north coast. Here at Túcume however, there are few visitors.

It is not hard to get to the site. Combis leave regularly from Chiclayo and Lambayeque, dropping passengers in the modern village of Túcume, from which an quick mototaxi ride leads to the ruins. By car or taxi, it is about a 30 minute ride from Chiclayo.

There are two main trails marked out across the desert plain in Túcume. One leads to Cerro Purgatorio, a craggy hill overlooking the 26 pyramids that comprise the site. The trail winds across the scorched valley, between several of the pyramids, before arriving at a staircase leading to different scenic overlooks on the face of Purgatorio.

WikiPedia, too, has a short reference.

Then there’s a long and revealing article on the InkaNatura Travel Site, which I recommend you go to.

So what happened at Túcume to cause the civilisation to fail?  Maybe this 10-minute film gives the answers, but just a note to say that there are some potentially upsetting scenes for the younger or more sensitive among us.

So anyone sufficiently brave to say that history won’t repeat itself.

Wonder which would be the ‘cursed cities’?

Inequality, a rich man speaks!

A personal reflection offered by Nick Hanauer.

Mr. Nick Hanauer

I hadn’t come across Mr. Hanauer before but thanks to some Facebook comments by Patrice Ayme found this YouTube video that is well-worth watching.  That’s an understatement!

The fundamental message that is contained in this short video seems critical, well to me it does, to society (that’s all of us, by the way) understanding why so many things seem to be going so very wrong for so many people.  But let me stop there before it becomes another of my rants!

Who is Nick Hanauer?  Here is a small extract from Nick Hanauer’s website,

Nicolas J Hanauer is a partner with Second Avenue Partners, a Seattle venture capital partnership specializing in early state startups and emerging technology. He has had a hand in such companies as Amazon.com and aQuantive among others.

Hanauer’s career began with a position as executive VP of Sales and Marketing at Pacific Coast Feather Company, a family owned manufacturer of basic bedding. In his time in that role, he helped grow Pacific Coast from several million dollars to more than $300 million in sales. Hanauer subsequently served as the company’s Co-Chairman and Chief Strategy Officer and remains Chief Executive Officer.

In 1988, Hanauer co-founded Museum Quality Framing Company, a company that has emerged the largest of its kind on the west coast with 60 locations. Hanauer was also one of the first investors in Amazon.com in 1995, where he served as a Board Advisor until January of 2000.

In 1996, he founded and served as CEO of internet media company Avenue A Media (later re-named aQuantive, Inc.) and became Chairman of the Board upon the first public offering in 2000. aQuantive was purchased by Microsoft in August of 2007 for 6.4 billion dollars; the largest acquisition in Microsoft history.

Now the video; less than 6 minutes long – do watch it!

As  a one-time entrepreneur back in the 80’s I can vouch for much of what Mr. Hanauer proclaims in his video.  The essence of successful marketing for any business, large and small, is understanding your market. Seeing the customer’s world through the customer’s eyes would be another way of putting that.

In plain language that means carefully and closely understanding what your customers, both actual and prospective, require, objectively and subjectively, and providing it to them profitably.  As the middle-classes (don’t like the term but it will have to do) are often the largest market opportunity, then it does follow that a healthy and vibrant middle-class is going to be best overall for the health and vibrancy of a country.  Indeed, in this very inter-connected world, that really equates to the health and vibrancy of our planet.

Which so easily leads on to a core truth. This one.  If all the Governments democratically elected on this planet truly acknowledged the democratic foundation, as Lincoln so ably put it, “government of the people, by the people, for the people” then those governments would be united in the one most important task facing the people – creating a sustainable way for us to live on the only planet we have!

Apologies, it did turn into a rant!

You may also want to read this TED and inequality: The real story.

A lovely week-end interlude

Big thanks to John H. for forwarding this to me.

Sit back and relax.

Nothing more except to wish everyone, wherever you are, a peaceful week-end, above or below the surface of the ocean!

Playing with fire!

A republication of a powerful essay from Martin Lack.

Martin and I haven’t seen eye-to-eye on everything, as each of us would readily admit.  But there’s no taking away the power contained in many of Martin’s essays over on his Blog Lack of Environment.  Unlike me, Martin has strong academic credentials that he uses well to support his position.

Martin recently published a strong Post called It doesn’t have to be like this and has kindly given written permission for it to be republished on Learning from Dogs.

Tomorrow, I plan to expand on the fruit crop disaster that Martin refers to below.  So here is the essay,

—————

Planet Earth is not just another business!

 

It doesn’t have to be like this

In 1974, the former World Bank economist Herman E Daly published an article on ‘The Economics of the Steady State’, beginning with a quote from the famous scientist Sir Arthur Eddington: “But if your theory is found to be against the Second Law of Thermodynamics, I can give you no hope; there is nothing for it but to collapse in deepest humiliation.” Daly is also on record as having quoted Aleksandr Solzhenitsyn (from Letter to the Soviet Leaders [i.e. published in 1974]), who said: “Society must cease to look upon ‘progress’ as something desirable. Eternal ‘progress’ is a nonsensical myth. What must be implemented is a not a steadily expanding economy but a zero growth economy; a stable economy.”

The essential point of Thomas Malthus’ (1798) ‘Essay on the Principle of Population’ was that populations increase faster than the supply of food can be made available to meet their needs. With this in mind, in 1972, Meadows et al predicted that the biophysical limits to growth would be exceeded at some point within 100 years: “If the present growth trends in world population, industrialization, pollution, food production, and resource depletion continue unchanged, the limits to growth on this planet will be reached sometime within the next one hundred years. The most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity.”

Recent strange weather in the USA – specifically a very warm March followed by unseasonal frosts in May – has all but wiped out all kinds of fruit crops. This may not have been the industrial collapse envisaged by Meadows et al (that is yet to come), but it is evidence of the way in which anthropogenic climate disruption (ACD) – or what some would have us be more precise and call human induced rapid global overheating (HIRGO) – threatens our ability to feed ourselves.

In 1992, the Meadows et al team summarised their revised conclusions as follows:
— 1. Human use of many essential resources and generation of many pollutants have already surpassed rates that are physically sustainable. Without significant reductions in material and energy flows, there will be in the coming decades an uncontrolled decline in per capita food output, energy use and industrial production.
— 2. This decline is not inevitable. To avoid it two changes are necessary. The first is a comprehensive revision of policies and practices that perpetuate growth in material consumption and in population. A second is a rapid, drastic increase in the efficiency with which materials are used.
— 3. A sustainable society is still technically and economically possible. It could be much more desirable than a society that tries to solve its problems by constant expansion. The transition to a sustainable society requires a careful balance between long-term and short term goals, and an emphasis on sufficiency, equity, and quality of life rather than on quantity of output. It requires more than productivity and more than technology; it also requires maturity, compassion, and wisdom.

In general, Meadows et al have been consistently ignored. In 1993, frustrated by the absence of discussion on population growth in international politics, Garrett Hardin pointed out that: “Two centuries of intermittent wrestling with population problems have produced useful insights about the reality and nature of limits… Four centuries of sedation by the delusion of limitlessness have left humanity floundering in a wilderness of rhetoric… From this it must be inferred that someday political conservatism will once again be defined as contented living within limits. The limitless world view will have to be abandoned.”

In this context, the words growth and development should not be confused. As Daly has pointed out:
“the Earth may be developing but it is not growing.”!

In their 30-year update of Limits to Growth, in a section entitled ‘Why Technology and Markets Alone Can’t Avoid Overshoot’, the Meadows et al team pointed out that if we put off dealing with limits to growth we are more likely to come up against several of them simultaneously. With regard to the computer modelling undertaken, they observed that in most cases the simulations ran out of the ‘ability to cope’ when too much industrial output has to be diverted to solving problems; and concluded: “Growth, and especially exponential growth, is so insidious because it shortens the time for effective action. It loads stress on a system faster and faster, until coping mechanisms that have been adequate with slower rates of change finally begin to fail.”

Just because Meadows et al have not yet been proven right does not mean that they were wrong.

In Small is Beautiful (1973), E. F. Schumacher wrote: “The illusion of [mankind’s] unlimited powers, nourished by astonishing scientific and technological achievements, has produced the concurrent illusion of having solved the problem of production… based on the failure to distinguish between income and capital where this distinction matters most… A businessman would not consider a firm to have solved its problems of production and to have achieved viability if he saw that it was rapidly consuming its capital…”

What he meant was:

There is something fundamentally wrong in treating the Earth as if it were a business in liquidation. ― (Herman E. Daly)

The loss of a lovely Uncle

Please indulge me with this purely personal reflection.

My Uncle Peter died in his sleep at 1.30am UK time on Monday, the 21st May, 2012.  He was 91 and had been suffering from declining health for a while.

As my parting gift from across the seas, I just wanted to record the great inspiration that he was to both me and my son, Alex.

Peter was a great gliding fan (sailplane in American speak!).  He must have started gliding not many years after the end of the war in 1945.  Anyway, when I was a young lad, back in the mists of time, my Uncle Peter took me for a glider flight.  That left a memory in me that lay dormant for many years until the late 1970s when a colleague, Roger Davis, introduced me to the Rattlesden Gliding Club and that started a 25-year interest in gliding and later power flying.

My son, Alex, also when he was a young boy was taken up for his first flight in a glider by Uncle Peter and later flew with me many times both in gliders and power aircraft.  Today he is a Senior Captain with a British airline.

So, dear Uncle Peter, what an aviation inspiration you have been for two generations.

Uncle Peter and two generations of pilots.

As it happens, 1.30 am UK time on Monday the 21st was 5.30pm Arizonan time on Sunday the 20th.  At that very moment, well 5.26pm to be precise, Jean and I were watching the solar eclipse and I took the photograph below of what was the partial eclipse here in Payson.

Partial solar eclipse partly hidden by the pine trees.

A tribute to a wonderful family man with a great sense of humour.

Make your voice heard.

Center for American Progress Action Fund plea to all Americans

Friends,

For the first time in history, the Environmental Protection Agency has proposed to limit industrial carbon pollution from new power plants. This important action will slow the growth of the major pollutant responsible for global climate change. These new limits will have far-reaching public health impacts.

It’s up to all of us to demonstrate strong public demand for clean air: Make your voice heard now in support of carbon pollution limits for new and existing power plants

Power plants dump more than two billion tons of carbon and other toxic pollutants into the air each year—nearly 13,000 pounds for every man, woman, and child in the United States. With the proposed standard, though, a typical new coal-fired power plant would have to reduce its carbon pollution by 40 percent to 60 percent. Natural gas power plants should be able to comply with this standard without additional controls.

President Barack Obama has endorsed limits on carbon pollution from motor vehicles, which will ultimately reduce tailpipe emissions by six billion metric tons over the life of the program.

More than 120 health organizations have urged the government to reduce “the threat to public health posed by climate change and to support measures that will reduce these risks.” These health groups include the American Lung Association, American Public Health Association, American Thoracic Society, and others.

I proudly served as the administrator of the Environmental Protection Agency for eight years, and I know from experience how vitally important it is that citizens who support proposed public health standards that reduce pollution make their voices heard. Certainly, many of the companies emitting the pollution and other interests that oppose clean air standards will do so.

During the first month available for public comments, more than one million Americans took action to express their support for cleaner air, but we need your voice today!

Will you join us and more than one million Americans calling for cleaner air? Make your voice heard—click here to submit a favorable comment to the Environmental Protection Agency today! Thanks again! 

Sincerely,

Carol M. Browner
Distinguished Senior Fellow, Center for American Progress Action Fund

Just in case you want a reinforcing viewpoint, please do read this article from the Key Correspondents (KC) team website.

Coal-fired power damages health and the environment

Coal-fired power generation damages people’s health and contributes to climate change, according to a new study by academics at the University of Pretoria.

The study shows how coal-fired power stations run up large costs as a result of coincidental but often unavoidable side-effects electricity generation.

These ‘externalities’ include the creation of carbon dioxide, carbon monoxide, methane, oxides of nitrogen, sulphur oxide, mercury and a wide range of carcinogenic radio-nuclides and heavy metals during the combustion process.

The Business Enterprises department of the University of Pretoria conducted the study for Greenpeace Africa and Greenpeace International at Kusile power station in Emalahleni in September 2011.

According to the report: “In the generation of coal-fire power, the objective is electricity production, yet, as a side effect, emissions are also produced.

“Various epidemiological studies found that the mentioned pollutants contribute to the incidence of mortality.”

The study also measures the cost to the environment by determining the amount of potentially damaging emissions from a power station.

According to the report, Kusile power station emits 30m tons of carbon dioxide per year, on an annual consumption of 17m tons of coal.

The analysis provides strong evidence of the need for Eskom, the largest energy provider in Africa, to invest in alternative renewable energy sources and for the government to support such investment initiatives.

But Eskom is building more coal-fired power stations to add to new power stations in Kusile and Medupi in Lephalale, Limpopo, with the support of the Department of Energy.

Building new power plants also requires the construction of new coal mines and the expansion of existing coal mines.

There are fears that coal fired power plants like Kusile in South could severely contribute to climate change.

Just re-read that sentence above that spoke of Kusile power station, “Kusile power station emits 30m tons of carbon dioxide per year, on an annual consumption of 17m tons of coal.

So, please, if you are an American who cares for the future of your children and grandchildren, take action.

Weep for our oceans, too.

Our fate is also wrapped up in the ocean – another cause for tears.

In a very real sense, this Post continues from my writings of yesterday concerning James Hansen.

A year ago, the BBC reported the shocking state of our oceans.  It included this:

“The rate of change is vastly exceeding what we were expecting even a couple of years ago,” said Ove Hoegh-Guldberg, a coral specialist from the University of Queensland in Australia.

“So if you look at almost everything, whether it’s fisheries in temperate zones or coral reefs or Arctic sea ice, all of this is undergoing changes, but at a much faster rate than we had thought.”

But more worrying than this, the team noted, are the ways in which different issues act synergistically to increase threats to marine life.

Some pollutants, for example, stick to the surfaces of tiny plastic particles that are now found in the ocean bed.

This increases the amounts of these pollutants that are consumed by bottom-feeding fish.

Plastic particles also assist the transport of algae from place to place, increasing the occurrence of toxic algal blooms – which are also caused by the influx of nutrient-rich pollution from agricultural land.

In a wider sense, ocean acidification, warming, local pollution and overfishing are acting together to increase the threat to coral reefs – so much so that three-quarters of the world’s reefs are at risk of severe decline.

As Callum Roberts explains in a forthcoming book The Ocean of Life,

Prof. Callum Roberts

We have always been fish eaters, from the dawn of civilization, but in the last twenty years we have transformed the oceans beyond recognition. Putting our exploitation of the seas into historical context, Roberts offers a devastating account of the impact of modern fishing techniques, pollution, and climate change, and reveals what it would take to steer the right course while there is still time. Like Four Fish and The Omnivore’s DilemmaThe Ocean of Life takes a long view to tell a story in which each one of us has a role to play.

That book was recently reviewed in The Economist, from which I reproduce the following extracts,

The Ocean of Life: The Fate of Man and the Sea. By Callum Roberts.

Traditional attitudes towards the sea, as something immutable and distant to humanity, are hugely out of date. The temperature change that harmed the corals was not caused by human activity; yet it was a foretaste of what man is now doing to the sea. The effects of overfishing, agricultural pollution and anthropogenic climate change, acting in concert, are devastating marine ecosystems. Though corals are returning to many reefs, there is a fair chance that in just a few decades they will all be destroyed, as ocean temperatures rise owing to global warming. The industrial pollution that is cooking the climate could also cause another problem: carbon dioxide, absorbed by the sea from the atmosphere, turns to carbonic acid, which is a threat to coral, mussels, oysters and any creature with a shell of calcium carbonate.

The reviewer explains that, “The enormity of the sea’s troubles, and their implications for mankind, are mind-boggling. Yet it is equally remarkable how little this is recognised by policymakers—let alone the general public.” and then adds, to the author’s credit, ” There is also a dearth of good and comprehensive books on a subject that can seem too complicated and depressing for any single tome. Callum Roberts, a conservation biologist, has now provided one.”

The book review then continues,

He [Callum Roberts] starts with a bold claim: that anthropogenic stresses are changing the oceans faster than at almost any time in the planet’s history. That may be putting it too strongly. Yet there is no quibbling with the evidence of marine horrors that Mr Roberts presents.

Take overfishing. The industrialisation of fishing fleets has massively increased man’s capability to scoop protein from the deep. An estimated area equivalent to half the world’s continental shelves is trawled every year, including by vast factory ships able to put to sea for weeks on end. Yet what they are scraping is the bottom of the barrel: most commercial species have been reduced by over 75% and some, like whitetip sharks and common skate, by 99%. For all the marvellous improvements in technology, British fishermen, mostly using sail-power, caught more than twice as much cod, haddock and plaice in the 1880s as they do today. By one estimate, for every hour of fishing, with electronic sonar fish finders and industrial winches, dredges and nets, they catch 6% of what their forebears caught 120 year ago.

Overfishing is eradicating the primary protein source of one in five people, many of them poor. It also weakens marine ecosystems, making them even more vulnerable to big changes coming downstream.

For example, there is the matter of chemical pollution, mostly from agricultural run-off. This has created over 400 dead-zones, where algal tides turn the sea anoxic for all or part of the year. One of the biggest, at the mouth of the Mississippi Delta in the Gulf of Mexico, covers 20,000 square km (7,700 square miles) of ocean. An annual event, mainly caused by the run-off of agricultural fertilisers from 40% of America’s lower 48 states, it makes the one-off Deepwater Horizon oil-spill look modest by comparison.

Global warming is another problem. Hitherto, the sea has been a buffer against it: because the heat capacity of water is several times that of air, the oceans have sucked up most of the additional heat, sparing the continents further warming. Yet this is now starting to change—faster than almost anyone had dared imagine.

One effect of the warming ocean, for example, is to increase the density difference between the surface and the chilly deep, which in turn decreases mixing of them. That means less oxygen is making it down to the depths, reducing the liveability of the oceans. Off America’s west coast, the upper limit of low-oxygen water is thought to have risen by 100 metres. Where strong winds bring this water nearer to the surface, there are mass die-offs of marine life. Such events will proliferate as the climate warms.

This is a poor lookout for already put-upon fish. “Fish under temperature and oxygen stress will reach smaller sizes, live less long and will have to devote a bigger fraction of their energy to survival at the cost of growth and reproduction,” writes Mr Roberts. And that is before he gets to the effects of ocean acidification, which could be very bad indeed. Without dramatic action to reverse these processes, he predicts a catastrophe comparable to the mass extinctions of the Palaeocene-Eocene Thermal Maximum, when carbon-dioxide levels, temperature and ocean acidity all rocketed. He writes: “Not for 55m years has there been oceanic disruption of comparable severity to the calamity that lies just a hundred years ahead.” That would be hard to prove; it would be better not to try.

So what is to be done? Mr Roberts provides a hundred pages of answers, occupying roughly a third of the book. They range from the obvious—curbing carbon emissions—to technical fixes, like genetic improvements to aquaculture stocks. None is impossible; and Mr Roberts, almost incredibly, describes himself as an optimist. He writes, “We can change. We can turn around our impacts on the biosphere.” We had better do so.

Amen to that!

So want to know where to start?  Here’s a snippet of advice in terms of protecting our fish stocks,