New Scientist: Climate Change, brought to you by Statoil

2012 November 15
by Chris Vernon

New Scientist magazine are running a special feature on climate change this week. Five years on and climate change is looking worse than almost anyone projected. It’s a reasonable article, sure, there is the expected sensationalism (linking Greenland with >1m sea level rise by 2100 for example), but the general message is on the money. From Arctic sea ice through extreme weather, food production and especially human emissions the situation is deteriorating rapidly. Prof. Paul Valdes of the University of Bristol was quoted “Our emissions are not slowing, that’s the most scary aspect of our future.”. Echoing the message From University of Manchester’s Prof Kevin Anderson speaking in Bristol a few weeks ago.

The issue here is that as I read this article, on the New Scientist website, it’s surrounded by no fewer than three large adverts from Statoil. The magazine, possible even this very article is in front of me thanks to Statoil’s marketing budget – which presumably works, or they wouldn’t do it – facilitating their business. And their business in this case? Discovering and extracting new oil reserves. They are advertising for staff with the tag lines “We are looking for engineers who want to go longer, deeper and colder” and “Our megaprojects are waiting for you”. I can only assume they are talking about frontier activities, deep water or Arctic drilling.

Two problems; firstly New Scientist are part of the problem not the solution if they continue to support activities like this, providing their readership to Statoil’s HR department. Secondly, the very activity of prospecting for further hydrocarbon reserves is bankrupt. In the IEA’s World Energy Outlook 2012, published this month, they state that total carbon in known fossil fuels reserves equates to 2860 Gt CO2 if combusted, going on to say less than 900 Gt can be emitted up to 2050 for +2°C world (what they actually mean is a ~50% change of warming being less than 2°C). To put this into context, the World Meteological Organization’s Greenhouse Gas Bulletin (published this week) states 375 billion tonnes of carbon (equivalent to 1375 Gt CO2) has been emitted since 1750 and that approximately 37 Gt are being emitted annually. 24 years of current emissions uses up that 900 Gt budget, but as Valdes points out emissions are still rising with no near term peak in sight shortening this period. As I wrote earlier with regard to North Sea oil and gas “…already discovered reserves of fossil fuels are more than sufficient? If in fact it would be very unwise to burn all the current reserves, why bother looking for more?”.


Statoil: Part of the problem

Pumpkin Pie

2012 October 30
by Chris Vernon

We’ve had a lot of success growing pumpkins this year. 111 kg in total, 100% organic, and not those no-taste wannabe pumpkins the supermarkets sell for carving! Here’s the recipe for the pumpkin pies I’ve been making weekly for the last six weeks or so. It’s based on a 30 cm flan tin:

The Pastry

  • 165 g plain flour
  • 75 g butter
  • pinch of salt

The Filling

  • 145 g golden syrup (of maple syrup if you’re feeling posh)
  • 150 ml evaporated milk
  • 2 eggs
  • cinnamon, ginger, cloves and nutmeg to taste
  • ~1 kg of pumpkin
  • Sugar for sprinkling

1. Make the pastry in the usual way: rub butter into flour/salt, add very little water so it can be brought together with a cold knife. Then, in a plastic bag/cling-film and put it in the fridge to cool.
2. Roast the pumpkin in chunks with a little oil for around 30 minutes at 200 ºC.
3. Mix the syrup, evaporated milk, eggs, and spices all together, keeping a little egg back for brushing on the pastry.
4. Line the base of the tin with greaseproof paper and butter sides.
5. Roll out pasty, line tin, paint edge with egg and blind bake at 200 ºC for 8-10 minutes. Keep a little pastry back for the lattice.
6. Once pumpkin is soft, mash it into filling, leaving out the skins.
7. Add the filling to the tin and lay out the lattice on the top. Brush the top with egg and sprinkle with sugar.
8. Bake for around 30 minutes at 180 ºC

Pumpkin Pie

Pumpkin Pie

Why are UK gas prices increasing?

2012 October 12
by Chris Vernon

The media is full of stories about gas prices today. First British Gas (+8%) then nPower (+8.8%). I’ve two observations:

Firstly, there are lots of price data floating around, but it is all either relative percentage rises or total average household bills. This is the wrong way to think about energy. Gas is priced in pence per kWh. So why doesn’t any of the media coverage actually report the price? It’s almost as if we aren’t responsible for the kWh by kWh consumption, instead we’re just lumbered with an annual bill.

Secondly, there’s very little talk of the reason for the rises, the real reason. Quite simply it’s that UK production of has peaked in 2000 and started to decline. By 2004 we were no longer self sufficient and became a net importer. Over the last decade production has halved and prices have more than doubled.

These data aren’t shown on the BBC News website, so here they are, compressed into one simple chart:

UK annual gas cost, production and imports.

So what should we be doing about this?

The first priority is the reduce the number of kWh we use, this means reducing the amount of energy used in our homes. The Bristol based Centre for Sustainable Energy has a website full of energy advice here: They also have a freephone energy advice line to call to discuss domestic energy saving. It is very easy to reduce energy consumption by 8%, our bills need not rise.

My Week at The Bicycle Academy

2012 September 25
by Chris Vernon


It takes a lot of practice to produce a nice fillet braze around two tubes, coming together at interesting angles.

Last month I spent a week learning about bicycle frame construction at the country’s newest frame building school, The Bicycle Academy. TBA was founded last year by Andrew Denham, with money raised in large part through a crowd funding exercise raising over £40,000 in under a week. I was one of these 183 initial backers, pre-booking a course with master frame builder Brian Curtis, Andrew and Chris Sheppard. The BBC have an article and video about TBA here:
This was my third foray into the world of frame building, having previously built a frame with Dave Yates in Lincolnshire and attended a frame building workshop with Dario Pegoretti in Verona, Italy. Each experience has been very different from the last and I’m starting to appreciate what Dave said to me about there being as many ways to build a frame as there are frame builders. In Frome we were fillet brazing with oxyacetylene, where with Dave I built a lugged frame and in Italy Pegoretti used propane for the fuel gas.

Acetylene is the fuel of choice, however, it's also highly volatile and demands a lot of respect.

The main focus at The Bicycle Academy, rather than to build your dream bicycle, is to learn the skills of frame building. The frames the two of us on the course would build were a standard design, the ‘Africa Bike’, which once completed would be donated through charities Re-Cycle and World Bicycle Relief. I had already taken a 1-day brazing masterclass with Brian a month earlier and it didn’t take long to get my eye in on a few test pieces. I was particularly proud of the practice bottom bracket mock-up:
Bottom Bracket

Bottom bracket test piece. A lot of heat builds up in the BB which we have to learn to adjust for. Photo credit: A. Denham.

The workshop itself is a lovely environment, well lit with as much wall space given over to cycling artwork as the tool boards. This, along with the steady supply of biscuits and coffee make the space easy to work in whether brazing with all the protective gear on or just reading one of their library’s books on frame building, cycling heroes or more general metalwork.
Before long we were marking, cutting and filing the tubes and tacking our frames up in the jigs. The jig, custom made by Chris Sheppard, holds all the tubes in exactly the right place as they are tacked together.
It was not until the final day that the frame itself was brazed. This was all done in one process to avoid multiple heat cycles. After so much practice on scrap tubing and all the work that had gone into cutting and mitring the tubes to fit just right, it all came down to this last half hour. Andrew, a veteran of many builds knew exactly how to manoeuvre the hot frame around as I gradually worked the torch’s acetylene flame and the bronze filler rod around the joints.
The job doesn’t end with the brazing though. The frame alignment needs checking and adjusting if required, the head tube must be faced and reamed and the bottom bracket tapped and faced. Straightforward jobs with the workshop’s full complement of Park Tools. And with that the frame’s complete.
It’s not a super lightweight racer but it is robust, built to last in a tough environment. The rear dropouts are spec’d for 100 kg load! My frame has a unique code number so once it’s left Frome I should be able to track it and find out just where in the world it ends up.
Finished frame

The finished frame!

The week wasn’t all filing and brazing though. We also spent some time on the computer using BikeCAD Pro which seems like a easy way to play around with designs before cutting the steel. Unique to The Bicycle Academy is that graduates (wall of fame!) are able to return to the workshop and work on their own frame building projects, paying only for workshop time and materials. I’ll certainly be making use of this for my next project. Watch this space!
Next stop, Africa.

My finished frame - next stop Africa!

The Bicycle Academy schedule is currently full up, however, they will be taking new course bookings soon. Here’s the waiting list form, fill it in and they’ll get back to you as soon as space is available.

Apple Tree Grafting

2012 September 2
by Chris Vernon

Apple trees can’t be grown from seed. Well, the pip will grow but it will very likely produce a fairly unpalatable crab apple* and the tree will be large. When propagating apple trees we want to grow a particular variety; Bramley, Cox or Russet etc. and we want the tree to be a manageable size. The only way to grow a Cox is to clone an existing Cox – all Cox apple trees alive today are cones of the original (or clones of clones etc.). In order to clone the existing tree we take cuttings of scion wood in the winter when pruning the tree, typically first year growth of approximately pencil thickness. These ‘twigs’ are then grafted onto rootstocks in the early spring. The size of the eventual tree is determined by the choice of rootstock: a seedling rootstock will be a full sized apple tree but for most gardens or orchards, semi-dwarfing or even very small dwarfing rootstocks are preferred.


Apple rootstocks

The seedling, or standard rootstock is a third larger again than M111/M25.

This spring I bought ten MM106 for £2 each. A couple of months earlier I had attended an apple tree pruning workshop where along with learning the basics of pruning I was able to collect some scion wood from both Bramley and Fiesta (also known as Red Pippin). I also took some scions from the Worcester Pearmain on our allotment. The dry scion wood was wrapped in plastic and kept in the fridge to keep it dormant until it was time to graft. The ten trees were grafted on the 25th March 2012.

There are many ways to graft. I chose the ‘saddle graft’ as it seemed the simplest. An upwards pointing ‘V’ is cut into the rootstock and a matching hollow is cut into the scion so that it forms a tight fit. You can buy special grafting tape to wrap around the join but I used used strips of plastic carrier bag.

I’m writing this six months later on the 25th August having just removed the the plastic bindings (which in all cases stayed on tight). See below for the resulting grafts. Eight of the ten seem to have worked well, one didn’t take at all and one seems to have formed a good join but there are no leaves on the scion wood.

Grafted apple trees

10 apple trees.

Apple tree graft

Apple tree graft.

Apple tree graft

Apple tree graft.

*Unless you happen to be lucky. Erica’s great-grandfather (known as Grandpa Buxton) planted a pip from an apple he ate in the garden, and the resulting tree has produced many excellent cooking apples over the years. It was registered as a new variety and is now even available by mail order!

Unprecedented melting of the Greenland Ice Sheet

2012 August 18
by Chris Vernon

Last week NASA released new images of the Greenland ice sheet generated from satellite data showing that between the 8th and 12th of July 2012 the area of the ice sheet’s surface that was melting had increased from about 40 percent to an estimated 97 percent. On average during the summer approximately half of the ice sheet experiences such surface melting and this expansion of the melt area to include the highest altitude and coldest regions was described as “unprecedented” by the scientists at NASA. Such widespread melting has not been seen before during the past 34 years of satellite observations and melting at Summit Station, near the highest point on the ice sheet, has not occurred since 1889 based on ice core records.

Greenland Melt

Extent of surface melt over Greenland’s ice sheet on July 8 (left) and July 12 (right).

The Greenland ice sheet gains mass from rain and snowfall and loses mass by solid ice discharge to the ocean (iceberg calving) and runoff of surface melt water. During the period 1961-1990 these processes are thought to have been in balance with the ice sheet’s mass stable (Rignot et al., 2008). During the last two decades, however, both ice discharge and liquid runoff have increased resulting in the ice sheet losing mass over this period at an accelerating rate (Velicogna, 2009, Rignot et al., 2011). Changes to these two processes have contributed approximately equally to recent mass loss (van den Broeke et al., 2009). Whilst these NASA images do not provide data about how much snow and ice have melted or the direct effect on mass balance, they do indicate a significantly larger area of the ice sheet has been melting.

While this melting is an extreme weather event, associated with a series of unusually warm fronts passing over Greenland this summer, new research on the ice sheet’s albedo from Jason Box, a researcher with Ohio State University’s Byrd Polar Research Center, shows summer albedo has been decreasing over the last decade. This reduced reflectivity, particularly at high elevations as shown in the lower chart below, is associated with warming related feedbacks and means more energy is absorbed at the surface for melting leading Box to suggest earlier this year that it is reasonable to expect 100% melt extent within another decade of warming (Box et al., 2012).

Greenland Albedo

Greenland ice sheet reflectivity 0-3200m elevation

Greeland Albedo

Greenland ice sheet reflectivity 2500-3200m elevation

Jason’s latest albedo data are available here:

This post was originally written for the Cabot Institute blog at The University of Bristol where two of my colleges also offer their thoughts on this melt event.

Capturing a Swarm of Bees

2012 July 24
by Chris Vernon

We’ve only been ‘beekeepers’ for a few months so imagine our surprise when we get a call from someone at our local association informing us of a reported swarm and inviting us to go and collect it! Sure, we’ve read the books, watched the videos and have the equipment and insurance but neither of us has actually taken any part in a swarm capture before. So, of course we said yes!

Here’s the swarm as we found it on the morning of Sunday 22nd July 2012:


Small swarm of bees

According to Wikipedia, there’s an old English poem that goes:

A swarm of bees in May is worth a load of hay;
A swarm of bees in June is worth a silver spoon;
A swarm of bees in July isn’t worth a fly.

(Or possibly for the last line, “A swarm of bees in July, let them fly.“)

On top of that, this is by all accounts a small swarm. But this is the swarm in front of us and at the very least we owe it to the lady whose garden it’s in to remove it. Fortunately the bees were only about a foot off the ground, with the only difficulties being the cramped conditions behind the greenhouse and the fact they had settled through a trellis fence. With a little water spray to calm them it wasn’t too hard to sweep the majority off the fence and into the box. I had already made a another nuc (similar in design to this one I described earlier) so they went straight in there with the crown board leaving a small gap.


Most of the bees in the nuc

Within seconds it was clear that we’d captured the queen as many bees positioned themselves by the entrance and started fanning pheromones from the Nasonov gland on their abdomens.


Within seconds bees are fanning at the entrance

It was clear that not all the bees would enter the nuc until dusk so we explained the situation and said our good-byes until the evening. Returning at dusk all was quiet and every single bee seemed to be in the nuc, at least there were none on the fence or anywhere else we could see. Result! Without further ado we sealed the box and drove them home.

Only time will tell whether a swarm this size, at this time of year, most likely with a virgin queen will be able to build itself up in time for winter, especially given the variable weather this year. However, this has been another interesting experience on our beekeeping journey!

A week in the life of a frame of bees

2012 July 23
by Chris Vernon

Throughout the summer we are inspecting the bees as close to weekly as other commitments allow. On each inspection we take a quick photo of each frame. This allows us to study the frame in detail in our own time on the computer.

Two recent visits took place on Wednesday 4th July and Thursday 12th July. The swarm was hived on 16th of June so these inspections are +19 days and +27 days respectively. Since it takes 21 days from the egg being laid for a worker bee to emerge, on the 4th July all we had was lots of sealed brood. However, by the inspection on the 12th, it was all change!

The photos below show both sides of the same frame on each inspection. Click the images for high-resolution.

Frame of bees

Front of the frame, sealed brood on the left, recently emerged on the right.

Frame of bees

Back of the same frame.

By the 12th July much of the brood has emerged, increasing the colony’s size for the first time since the swarm was caught. Encouragingly, the recently vacated cells had all been cleaned out and recharged with new eggs! Restart the counter – these cells should be emerging sometime around the 1st August!

The wild comb on the bottom of the frame is the result of using a normal deep national frame in a 14×12 brood box. We have three such frames in the box currently which we’re planning to leave for the time being.

Bee inspection, with photos

2012 June 29
by Chris Vernon

First a little history about these bees. The swarm was caught near Bradford-on-Avon on the 15th June and they went in our hive on Saturday 16th June. We just transferred them on the three National sized brood frames (foundation) they came on, filling the rest of the brood box with eight 14×12 frames of foundation. The attached photos are from the inspection on 28th June, 12 days later. In each case, click for a high resolution photo.

This is the best 14×12 frame. It was clean foundation 12 days ago. Now it has capped stores at the top, larvae in the middle and pollen, including some amazing pink stuff, towards the bottom.

Bees on a 14x12 National frame

Bees on a 14x12 National frame

The first sealed brood, which means new worker bees in ~12 days. Cells are sealed on day 9 after laying, suggesting our queen was probably already mated when she swarmed. Also note the fat larvae next to the capped cells, they’re next!

First sealed brood

First sealed brood

I love this photo, so sharp and amazing pollen.



Not the sharpest photo – but does include the queen, Queen Antoinette. The next one will be Boadicea, then Cleopatra and so on. Can you spot her?

The queen bee

The Queen, Antoinette

Photos taken by Wyc as I inspected the frames.

Building a Nucleus Bee Hive

2012 June 27
by Chris Vernon
Nuc hive

The finished 14x12 nuc hive

A nucleus hive is a small bee hive. Where a conventional hive holds 10-12 frames in the broodbox and can be expanded upwards by adding supers for honey storage, a nucleus or ‘nuc’ hive only holds 3-6 frames of brood. They are typically used for housing small colonies that result from a captured swarm or a split from a large colony. They are handy to have around, as the late Dave Cushman wrote:

Many beekeeping problems can be solved by either putting something into a nucleus or taking it out.

Whilst we bought our 14″x12″ National hive, I decided to have a go at making a nuc. Since we’re using extra deep brood frames, I’m building the nuc to take these. Browsing the web with this in mind a few weeks ago I came across Martin Adams’ album on Photobucket. Home made nucs and plans! The Internet really is a remarkable thing, we’ll miss it when it’s gone! I’ve copied the plans below in case the Photobucket site is unavailable in the future.

With cutting list in hand I bought a single 8′ by 4′ sheet of 12mm external plywood from B&Q. They helpfully made a few appropriate cuts so I could get it in the car. There’s enough material for two, with a good bit of spare. You can get five out of two sheets, but I figured that might be too much of a good thing! With the cutting done, it was simply glued and screwed together with powerdrive (deep cut thread) screws. Click the thumbnails to enlarge:


Half a hive

Edges glued and screwed

Frames in nuc

Holds 6 frames

Bee space

Perfect bee space

Hive vent

Mesh over vent

There’s a crownboard not shown in the photos with a hole for a feeder. The roof space is 100mm, enough for the 4 pint rapid feeder. I’ve painted the hive with an exterior grade woodstain, five coats in all, to provide a degree of weather proofing. The nuc is currently out in the garden, with some frames of foundation and a few drops of lemongrass oil. The hope being that a nearby swarm might move in!

In all the nuc cost just under £20 to build.

Nuc hive

The finished hive before five layers of woodstain.

Plans from Martin Adams, click to enlarge:

National nuc hive

14"x12" National

Nuc hive

Regular National