Archive for September, 2015

Volcanic Clouds

September 28, 2015
The estimated average air temperature above the land surface of the Earth. The thick black line. The squiggle lines are data and the grey lines give an indication of uncertainty in the estimate. Th bold black line shows the results of a model based on carbon dioxide and the effect of named volcanoes.

The estimated average air temperature above the land surface of the Earth. The squiggly lines are data and the grey lines give an indication of uncertainty in the estimate. The bold black line shows the results of a model based on the effects of carbon dioxide and the effect of named volcanoes. Figure is from the Berkeley Earth Temperature Project

The explosion of Mount Tambora in 1815 was the largest explosion in recorded history. Its catastrophic local effects – earthquakes, tsunami, and poisonous crop-killing clouds – were witnessed by many people including Sir Stamford Raffles, then governor of Java.

Curiously, one year later, while touring through France, Raffles also witnessed deserted villages and impoverished peasantry caused by the ‘year without a summer’ that caused famine throughout Europe.

But at the time no-one connected the two events! The connection was not made until the late 20th Century when scientists were investigating the possibility of a ‘nuclear winter’ that might arise from multiple nuclear explosions.

Looking at our reconstructed record of the air temperature above the land surface of the Earth at the head of this article, we can see that Tambora lowered the average surface temperature of the Earth by more than 1 °C and its effects lasted for around three years.

Tambora erupted just 6 years after a volcanic explosion in 1809 whose location is still unknown. We now know that together they caused the decade 1810-1820 to be exceptionally cold. However, at the time the exceptional weather was just experienced as an ‘act of god’.

In Tambora: The Eruption that changed the world, Gillen D’Arcy Wood describes both the local nightmare near Tambora, and more significantly the way in which the climate impacts of Tambora affected literary, scientific, and political history around the globe.

In particular he discusses:

  • The effect of a dystopian ‘summer’ experienced by the Shelleys and Lord Byron in their Alpine retreat.
  • The emergence of cholera in the wake of a disastrous monsoon season in Bengal. Cholera went on to form a global pandemic that eventually reached the UK through trade routes.
  • The period of famine in the rice-growing region of Yunnan that led to a shift towards opium production.
  • The bizarre warming – yes, warming – in the Arctic that led to reports of ice free northern oceans, and triggered decades of futile attempts to discover the fabled North West Passage.
  • The dramatic and devastating advance of glaciers in the Swiss alps that led to advances in our understanding of ice ages.
  • The ‘other’ Irish Famine – a tale of great shame and woe – prefacing the great hunger caused by the potato-blight famines in later decades.
  • The extraordinary ‘snow in June’ summer in the eastern United States

Other Volcanic Clouds

Many Europeans will recall the chaos caused by the volcanic clouds from the 2010 eruptions of the Icelandic volcano Eyjafjallajökull (pronounced like this  or phonectically ‘[ˈeɪjaˌfjatlaˌjœːkʏtl̥]).

The 2010 eruptions were tiny in historical terms with effects which were local to Iceland and nearby air routes. This is because although a lot of dust was ejected, most of it stayed within the troposphere – the lower weather-filled part of the atmosphere. Such dust clouds are normally rained out over a period of a few days or weeks.

Near the equator the boundary between the troposphere and stratosphere – known as the tropopause – is about 16 km high, but this boundary falls to around 9 km nearer the poles.

For a volcanic cloud to to have wider effects the volcanic explosion must push it above the tropopause into the stratosphere. Tiny particles can be suspended here for years, and have a dramatic effect on global climate.

Laki

Tambora may have been ‘the big one’ but it was not alone. Looking at our reconstructed air temperature record at the head of this article, we can see that large volcanic eruptions are not rare. And the 19th Century had many more than the 20th Century.

Near the start of the recorded temperature history is the eruption of Laki in Iceland (1783-84). Local details of this explosion were recorded in the diary of Jon Steingrimsson, and in their short book Island on Fire, Alexandra Witze and Jeff Kanipe describe the progression of the eruption and its effects further afield – mainly in Europe.

In the UK and Europe the summer consisted of prolonged ‘dry fogs’ that caused plants to wither and people to fall ill. On the whole people were mystified by the origin of these clouds, even though one or two people – including the prolific Benjamin Franklin – then US Ambassador to France – did in fact make the connection with Icelandic volcanoes.

Purple Clouds

Prior to the two books on real volcanic clouds, I had previously read a fictional account of such an event: The Purple Cloud by M P Shiel, published in 1901, and set in the early decades of that century.

This is a fictional, almost stream-of-consciousness, account of how an Arctic explorer discovers a world of beauty at the North Pole – including un-frozen regions. But by violating Nature’s most hidden secrets, he somehow triggers a series of volcanic eruptions at the Equator which over the course of a couple of weeks kill everyone on Earth – save for himself.

I enjoyed this book, but don’t particularity recommend it. However what is striking to me now having since read accounts of these genuine historical events is that the concept of a globally significant volcanic cloud actually existed at the end of the nineteenth Century.

Final Words

The lingering flavour of these books – factual and fictional – is that historically there have been poorly-appreciated tele-connections between historical events.

Now, we live in a world in which the extent and importance of these global tele-connections has never been greater.

And in this world we are vulnerable to events such as volcanic clouds which – as the chart at the top of the page shows – affect the entire world and are not that rare.

Road to Nowhere

September 21, 2015
A road to nowhere. This road is 60 metres below the surface of the Finnish peninsula on Olkiluotu and leads to giant silo - the end of the road for low-level and intermediate-level radioactive waste in Finland.

A road to nowhere. This road is 60 metres below the surface of the Finnish island of Olkiluotu and leads to two giant silos – the end of the road for low-level and intermediate-level radioactive waste in Finland.

I wrote last week that one of the things we in the UK need to build in ‘someone’s back yard’ is a Nuclear Waste Repository.

Last week during a progress meeting for the European Metrodecom project, I joined a visit to the site of such a repository in Finland, on the island of Olkiluoto.

Olkiluoto Island houses two working nuclear reactors, each generating approximately 400 MW of electricity for more than 95% of the time. It is also home to the first construction of a new type of reactor which may (or may not) be built at Hinkley Point in the UK. When completed this third reactor should generate approximately 1600 MW of electricity.

But more important than nuclear generation, Olkiluoto is home to Onkalo (meaning ‘Cave’ or ‘Cavern’) the world’s first final disposal site for high-level waste.

The lower levels of Onkalo are still under construction and so sadly we were not able to visit the tunnels 400 m below the surface. But we did visit the 60 m deep repositories for low-level and intermediate-level radioactive waste .

Importantly, these are not ‘storage’ facilities, but represent sites for the final disposal of this waste. When they are full, they will be sealed off and left.

The visit

After three briefings on Olkiluoto in general and Onkalo  in particular, we boarded a bus for a tour of the site, ending up at the entrance to the so-called VLJ repository.

We were asked not to take pictures of the site, but once inside the repository we were told that we could ‘fill up our memory cards’.

We put on obligatory hard hats, and after a large roller-door was raised, we descended on a sloping roadway mined from solid granite.

The tunnel descends, carved out of solid granite.

The tunnel descends, carved out of solid granite.

After 15 minutes or so we reached a large chamber containing two gigantic silos, each about 20 metres in diameter and about 40 metres deep.

Panoramic picture of the Low-level (on the left) and intermediate level (on the right) wast repository.

Panoramic picture of the low-level (on the right) and intermediate level (on the left) waste repository. (Picture from Simon Jerome). Click for larger version.

Above ground, waste is packed into concrete crates about 2 m x 2 m which are then driven along the ‘road to nowhere’ aka the repository. And then lowered by crane into the silo where they are carefully stacked.

Waste is packed into these concrete containers and lowered into the silo

Waste is packed into these concrete containers and lowered into the silo

We weren't allowed to peek into the silos, so this my photograph of a stock photograph of the silo showing the stacks of waste.

We weren’t allowed to peek into the silos, so this my photograph of a stock photograph of the silo showing the stacks of waste.

Most of this waste is ‘operating waste’ from the two existing nuclear reactors on site: typically single-use garments used by maintenance workers and operators, and ion-exchange resin used in maintaining water purity.

The current plan calls for three similar silos to be built to accommodate the decommissioned remains of the two existing reactors at the end of their lives.

Onkalo

By the time that Olkiluoto 1 and 2 reactors are being decommissioned, the Onkalo deep repository will be ready to take all the high-level waste that the reactors have produced over their lifetime.

The fuel rods from the reactors will be removed and placed in water storage for about 10 years – a backlog of fuel awaits the availability of the repository. Bundles of fuel rods are then placed inside a strong cast-iron frame and sealed inside a 4 metre long copper cylinder.

Fuel rod bundles (one visible) are placed in a cast Iron frame (right) chosen for its strength. This is then plced inside a copper cylinder chosen for its corrosion properties.

Fuel rod bundles (one visible) are placed in a cast iron frame (right) which is then placed inside a copper cylinder. Cast iron is chosen for its strength and copper is chosen for its corrosion properties.

Significantly, no attempt is made to reprocess to the fuel. This is somewhat wasteful since useful nuclear material remains unburnt in the fuel rods. But this choice dramatically simplifies the disposal.

Simulated gallery in Onkalo. The tops of several cylinders are visible. When the gallery is full, the space will be back-filled with clay and sealed with a concrete plug.

Simulated gallery in Onkalo. The top of one cylinder is visible and locations of its neighbours can be seen in the distance. When the gallery is full, it will be back-filled with clay and sealed with a concrete plug.

Comparison with the UK

The contrast between the rational Finnish approach and the UK’s ‘let’s put this off and make it someone else’s problem’ approach could not be greater.

Admittedly, Finland’s ‘back yard’ is bigger than the UK’s: they have one tenth our population and twice our land area. And additionally they require a much smaller repository than the UK will require.

However, Finland has begun preparing for disposal of waste before their first generation of reactors have reached the end of their life.

In contrast the UK has been generating about 20% of our electricity from nuclear power for around 50 years, so we have benefited profoundly from nuclear power. Our first generation reactors are now being decommissioned and we have lots of spent fuel and other types of radioactive waste.

But despite spending hundreds of millions of pounds planning, in practical terms, we have done absolutely nothing about safely disposing of nuclear waste – including high level waste.

Some is stored in warehouses, but shamefully a great deal is stored in filthy outdoor pools.

Outdoor storage of nuclear waste at Sellafield

Outdoor storage of nuclear waste at Sellafield.

My visit filled me with a sense of national shame. But overall I feel pleased to have seen this site with my own eyes. Finland has shown the world that safe disposal of nuclear waste is possible, and not at an extravagant cost.

And if they can do it, then why can’t we?

 

Ready for final disposal

Ready for final disposal

If not my back yard, then whose?

September 14, 2015
Overview of the proposed third runway at Heathrow.

Overview of the proposed third runway at Heathrow.

As I write this at 10:18 p.m. on 10th September 2015, an aeroplane has just flown overhead, disturbing the peace and quiet of Teddington.

It’s a regular occurrence happening roughly every 3 minutes for bursts of three hours every other day. And randomly at other times. This morning it started at 5:45 a.m.

It’s pretty unpleasant, but not surprising since I live roughly 10 kilometres from Heathrow airport. It is inevitably occasionally noisy.

For me – like most people in the area – this is just a fact of life and I just get on with things. Some people find it unbearable.

And there are much worse places than Teddington. For example, in Richmond the noise is much worse.

So what do I think about the proposal to build a third runway at Heathrow?

From a personal point of view I would obviously like the airport noise to go away.

But I acknowledge that the country needs airports, and  that those in the South-East are full.

The government asked someone to consider all the facts – balance the pros and cons with the cost – and they said that a third runway should be built at Heathrow.

And for me – that’s it.

If it’s not built in my ‘back yard’ it will be built in someone else’s.

The reason I feel this is simple: the country needs lots of things besides airports – some much more urgently. For example:

  • We need houses – and lots of them.
  • We need wind turbines – and lots of them
  • We need places to permanently dispose of nuclear waste.

And the people who live in the places where these things are proposed inevitably complain that a thing – whatever it is – will make there lives marginally worse.

In short, they complain because something will change which benefits their fellow citizens, but brings no personal benefit to them.

So I don’t feel I can object to Heathrow expansion given that it’s a decision based on the best interests of the UK and was arrived at democratically.

Choice and cost

Insisting that an airport be built in a place which doesn’t degrade my quality of life would cost money. The Heathrow plan will cost about £20 billion but – for example – the cost of building an airport in the Thames estuary could be in excess of £100 billion.

This is equivalent to asking the other 37 million working age people who don’t live near Heathrow to pay an additional £2,400 each to keep me in the style to which I have become accustomed.

Similarly:

  • Placing excessive restrictions on where houses can be built inflates the price of houses and brings misery to millions.
  • Campaigning against Wind Turbines slows down our transition to a low-carbon electricity supply causing the unnecessary emission of millions of tonnes of carbon dioxide.
  • Objecting to the construction of a nuclear waste depository extends the highly unsatisfactory storage that currently exists – costing everyone else bilions of pounds while we wait to find a County Council to which will allow the project to go ahead.

The projects I have mentioned – and lots of others – represent cases where projects of national importance are routinely blocked by small numbers of people complaining very loudly.

But there is a bigger picture and we need to keep it clearly in mind if we want infrastructure which meets the needs of all the people that live here.

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Post Script: I’ve finished editing this article on Sunday night 13th September, and I noticed the last plane fly over at 11:09 p.m. It’s been a long and noisy day – it must be time for bed.

How Apollo Flew to the Moon

September 6, 2015
The Moon photographed above some beach grass in Northumberland

The Moon photographed above some beach grass in Northumberland

On my recent holiday in Northumberland, I both photographed the moon, and read about how almost 50 years ago, human beings landed on its surface.

This article is a review of the book I read: ‘How Apollo Flew to the Moon‘ by W. David Woods.

Staring at the moon and considering what we now know about its distance from Earth, its size, and its inhospitable surface, is an exercise in bridging emotional and intellectual understanding.

I have long-considered that the Apollo programme of manned spaceflights to the Moon to have been an exemplar of the power of human intellect, and overall one of humanity’s exceptional achievements.

The enormous cost of the programme (4% of the US Federal budget in 1967) was – in my opinion – well justified by the cultural shift it engendered.

We went to the Moon and discovered the Earth‘ is a truth expressed by many, including several of the early astronauts.

However this book is not about the cultural impact of the programme, but about how the journey was made. For anyone with a technical disposition the book will fascinate.

I took all 500 pages of the book on holiday with me and self-indulgently read it slowly from cover to cover: it was enormously enjoyable.

After an overview, the book follows the Apollo 11 mission through all its stages, sprinkling in astronaut comments and explaining the differences between earlier and later missions.

There are many fascinating details, but what came through to me above everything was NASA’s pervasive mindset of constantly, painstakingly, meticulously and expensively planning for failure.

The philosophy of not just being aware that an operation may fail, but making detailed plans for what you will do when it does is a lesson for anyone who wants a complex plan to succeed.

And not only were there back-up plans for failure, there were plans for failure of the back-up plans! Only at one or two key points in the entire mission were there operations which simply had to work.

So, for example, when their spacecraft fired a rocket engine to leave Earth’s orbit and head towards the Moon –  or rather where the Moon was going to be in three days time – the rocket burn placed them into a so-called ‘free-return trajectory‘.

Thus if something went wrong on the voyage, or the rocket engine failed to fire – the spacecraft would sail around the Moon and head straight back to Earth.

When launched towards the Moon, the Apollo spacecraft was placed in a “Circumlunar-free-return-trajectory” . This meant that unless they did something positive to enter the Moon’s orbit, they would return to the Earth. Picture by NickFr Licensed under Public Domain via Wikipedia

Overall, the book is a great read for the technically minded. And in addition to the narrative there are occasional superlatives – like ‘vista-points’ on a highway – where you can stop and simply wonder.

  • The total mechanical output power of five first stage rockets was 60 GW. This is equivalent to peak electrical supply of the entire United Kingdom.
  • On its return from the moon, its speed just before entry into the Earth’s atmosphere was more than 11 kilometres per second.
  • Since Apollo 17 returned in 1972. no human being has been more than 500 miles from Earth’s surface.


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