Monthly Archives: April 2015

The hot dirt on compost

By Su Wild-River

It’s well known that compost generates heat. Clever people even heat their houses, run cookstoves and cars off compost. Here’s a little look at a humble backyard compost system through the lense of a thermal imaging camera.

A thermal imaging camera is really a heat sensor, not a camera which shows what you see with your eyes. In these photos, the hottest areas are shown in white, and a rainbow spectrum going through red, to yellow, green and finally blue, show colder areas.

The photographs were taken on a cool autumn morning, with an ambient temperature around 14 degrees Celsius (about 57 Fahrenheit). The yellow glowing thing is a ‘compost dalek’, or plastic drum with air vents at the top, and compost inside.

Its interesting to see in the first pair of photos, that the water-filled pot at the front, and the two ceramic pieces behind are the coolest spots around. These are the high thermal mass areas of the photographs, and I was surprised at first to see that they were so cold, as I usually think of thermal mass as warm. Of course the main feature of thermal mass is not that it stays warm, but that it moderates temperature changes. Large thermal mass elements, like water tanks insulated slabs change temperature so slowly that they stay around the long-term average ambient temperature.

Compost by Kath McCann. Photos by Su Wild-River

Compost by Kath McCann. Photos by Su Wild-River

The outside of the compost dalek registers a temperature of around 16.5 degrees Celsius. It is much warmer than everything around it, and only the vents are colder.

Looking inside without turning the compost gives us a look at even higher temperatures. The hottest parts here are about 20 degrees Celsius. They are the deeper parts of the compost, so we dug a bit further.

Compost by Kath McCann, Photos by Su Wild-River

Compost by Kath McCann, Photos by Su Wild-River

Only an inch or so down, the hottest temperature was 26.4 degrees Celsius. This is more than 10 degrees above the background temperature.

Compost by Kath McCann, Photos by Su Wild-River

Compost by Kath McCann, Photos by Su Wild-River

Now this compost is owned by Kath McCann, a keen gardener, and a good composter, but not someone who is using the stuff to heat her house. It seems as if even humble compost could make enough heat to warm us up, if only we plan and use it wisely.

So there you go. Compost really is warm. How could you be using yours?

How to (Not) undermine yourself in one easy lesson

By Su Wild-River.

Today I started a new project with three first-time collaborators. It’s an exciting topic and I’m thrilled to be a part of it. Two team members are published experts in the field. The other directs a government program on it. I know quite a bit about other things that are broadly relevant.

I bring other areas of expertise.

When our first draft proposal didn’t make the grade, it was me who found the pathway between what the client wanted, and what we could deliver. When team members balked at a less interesting scope, I gave an upbeat reminder that it’s the client’s prerogative to choose what they pay for. I edited our proposal to ensure a focus on what they wanted. These interventions were key to us being hired to do the work.

Many times I was so out of my depth that I felt like I was reading a different language. At first I couldn’t discern if my partners proposed to measure, model or review parameters. I thought they had misunderstood key terms, but knew it was more likely my own error. I was flummoxed by the difference between spatial and categorical, historical and predicted factors. I knew none of the acronyms. But I kept on reading and redrafting until every paragraph told me a coherent story, repeatedly deleting my initial edits and replacing them with something sensible. With about eight hours work I became familiar with a whole new field of work.

The expertise I applied here is to be comfortable in the dark. I was instructed in this skill by my first year statistics lecturer and it is one of the most important things I have ever learned. It means moving beyond a fear of failure to embrace the unknown. It is learning to love the cramping terror in the pit of my stomach, which is the feeling of creativity. It demands a paced journey through discomfort while knowledge replaces ignorance.

I am grateful that in this project, I had time to move through this process alone at my own computer. By the time I actually met my team members I had some very good questions to ask. So good in fact, that when we met together with the client, I asked the first three questions. I brought some good new ideas which spurred animated discussion. And all this while still largely in the dark about at least half of what was being said.

I made only one major mistake. That was to start a sentence “So you must have noticed by now that I’m not the expert here, but I wonder…..”

This phrase was self-defeating and undermining. It positioned me as a pretender in others’ minds. In hindsight, I think I don’t think anyone had noticed that I was out of my depth until that moment, but in saying this I sowed a seed of doubt about my every contribution.

I started the sentence with an apology because I wasn’t sure if my question had been covered before. What should I have done instead? Not ask the question? Ask a simpler one instead? Ask it without the opening phrase? Any of these would have been better.

So what was my motivation for underselling myself? I think it was fear of having my cluelessness discovered, and a sense that it was safer to acknowledge it up front. But this is wrong on so many levels. My low-level specialist expertise has value so long as I am willing to fit in, learn, and help. Asking an obvious question can show the experts that part of their story is simply not clear. Naming the opacity gives my team the edge in communicating findings effectively. And all of that other related knowledge can help us to fit our project into other the bigger picture.

And for my next trick, I’ll try to remember these lessons the next time it counts.

How do you feel in the dark, and what do you do for a torch?

Photo by Tim McCann

Photo and artwork by Tim McCann

Why I love my wetsuit, or living in the second law of thermodynamics

By Su Wild-River

Snorkeling in an Australian South Coast Autumn can be a chilly business. But last weekend wasn’t so bad. Our best estimate for the water temperature was 18ºC, and so Tim, who has better underwater staying power than the rest of us, decided not to wear his wetsuit. Armed with my thermal imaging camera, I decided to see what difference a wetsuit makes.

A thermal imaging camera is really a heat sensor, not a camera which shows what you see with your eyes. In these photos, the hottest areas are shown in white, and a rainbow spectrum going through red, to yellow, green and finally blue, show colder areas. The photos are calibrated so that the same colour has the same temperature in each of the pictures.

First, I photographed Kath and Tim before they went into the water. Tim is on the left, without a wetsuit, and Kath on the right in her full body suit, or ‘steamer’. Bare skin is showing up hottest in these photos, and you can see it on both faces, hands and feet, but only on Tim’s arms and torso. The highest temperatures here are reading 31ºC. (You can’t see to the top of the scale in this picture because I have calibrated it lower, for consistency with the cold pictures below).

Wetsuits warm 2

Next, we all went snorkeling, and saw the most wonderful fish, sting-rays, crays and an octopus. After shivering for a while, we got out. The next photo shows Tim and Kath after they got out. Now they both look the same colour as one another all over, and are now thermally camouflaged with the ambient temperature of 16-18ºC.

Photo by Su Wild-River

But hang on, did the wetsuit keep Kath warm or not? In fact, Kath is showing up as cool as Tim because all of her heat is trapped underneath the wetsuit. But she was too cold to take it off and pose again. I had to do it myself.

I had been wearing a ‘spring suit’, which ends above the knees. Here’s the photo of my legs with the wetsuit on. Like Kath, the colours are similar to background, and the same both above and below my knees, ie, with and without the wetsuit.

Photo by Su Wild-River

But now the wetsuit comes off and suddenly you see some warm skin. Underneath my wetsuit, my skin maintained about 22ºC, which is closer to my healthy body temperature of about 36.5-37.5ºC.

 

Photo by Su Wild-River

What’s going on here?

Our bodies our demonstrating the second law of thermodynamics, which covers the conservation of energy. This states that heat (and other energy) moves from hot areas to cold areas. Our bare skin was uselessly transferring the heat within our bodies into the ocean, and in the process it was making us all cold. But the parts of us under the wetsuits weren’t transferring nearly as much heat, and so they stayed warmer. The outside of our wetsuits, and all of our skin that touched the water, ended up as cold as the ocean but the rest of us stayed a bit warmer. Our subcutaneous fat and skin were also insulating us against the elements, slowing the transfer of heat to the world and making our skin cooler than our blood, even before we went in the water.

Photo by Su Wild-River

How cold were we? Not cold enough for a brain freeze. But all of our toes and fingers were pretty chilly.

hot feet 10-32

It took over an hour for my feet to warm back up.

Adventures are great. But one of the pleasures is getting comfortable afterwards.

Photo by Su Wild-River

When we got back in the car, my fingers absolutely loved the heater vent.

How do you experience the second law?

 

Regeneration and Conservation Connections

This article was first published at: http://www.uppershoalhavenlandcare.com.au/wp-content/uploads/2015/03/Autumn-2015-LP-for-web-publication.pdf

By Lesley Peden and Su Wild-River

At the recent Regen Festival, I delivered a workshop for the Upper Shoalhaven Landcare Council with Kristy Moyle from South East Local Land Services and Lesley Peden from Kosciuszko2Coast.

The workshop focus was connectivity conservation. This recognises the particular needs of different species for moving around within landscapes.  Animals like eagles, owls and kangaroos can readily move between disconnected, or thin patches of habitat, but most native species can’t.  Local threatened species like the Flame Robin, Golden-tipped bat, Green and Golden Bell Frog, Squirrel Glider, Long-nosed Potoroo, Smoky Mouse and Rosenberg’s Goanna, all need relatively in-tact vegetation to move about in the landscape. Disconnections within the Great Eastern Ranges can trap these species when fire, flood, drought or even a successful breeding season mean that individuals must move to survive.

During the workshop we discussed the ecological importance, and urgency of regeneration in the broad context of connectivity conservation. A key point is that the best conservation outcomes are achieved by being aware of the context and the different needs of the species using the landscape.

Food security and the vegetable decathlon

By Su Wild-River

This post was first published at http://nofunnybusiness.net/2014/03/food-security-and-the-vegetable-decathlon/

Scientists are tackling global food insecurity in a range of ways. They are researching crop narrowing, analysing hunger and health, connecting food risks to climate change, debating genetic engineering solutions and making a Doomsday Vault. As a scientist, I’m doing the heirloom vegetable decathlon.

Khoury et al’s recent paper on the “increasing homogeneity in global food supplies and the implications for food security” quantifies the global shift away from highly diverse food sources 50 years ago to a much smaller set of globally important, energy-dense foods now. The winners in the food supply race include wheat, rice, soybeans, palm and sunflower oil, potatoes and sugar and we rely ever more heavily on them. Wheat for example is now a key food in more than 97 % of countries. These narrow crop types have displaced coconut, cassava, sorghum, millet, rye and sweet potato and many more from traditional and national diets, being cheaper, easier to grow and quicker to prepare.

On the positive side, easy-to-grow, energy-dense foods have helped feed the world’s hungry people. The United Nations Food and Agriculture Organisation estimates that total number of people who are not hungry increased from 4,370 million people in 1990-2 to 6,225 million in 2012.

Medical scientists are examining the risks. One risk is to our health. People who eat mainly energy-dense foods are at risk of obesity, heart disease and diabetes.

Crop diseases and their solutions have attracted scientific research. The southern corn leaf corn blight of 1972 and the Irish potato famine of 1846 show that crops with limited genetic variability can be highly susceptible to new disease outbreaks. Agricultural scientists are warning that with billions of people now relying on fewer food crops, new disease outbreaks could make us hungry. Crop heterogeneity is a possible solution and works by maintaining a rich gene pool through strategic interbreeding of common crops with wild cultivars. Genetic engineers are also quick to offer solutions, and transgenic plants are being developed with resistance to viruses, fungi, bacteria and nematodes. But few commercial GM cultivars are available in the short-term, and ecologists caution that over time they may bring new threats such as superweeds and toxic pesticides. GM crops they say, are at best a contentious solution to food insecurity.

But in addition to problems identified by food and health scientists, broader issues are at stake. Climate change is widely understood as an emerging, serious threat to food security. The European heatwave in 2003 and American heatwave in 2012 both reduced crop production by up to 30 % and sent prices soaring. Scientists have considered whether extra carbon dioxide and warmth could have positive food production consequences, but in 2013-4 the International Panel on Climate Change reported that negative impacts have been more common.

A Doomsday Vault in the Arctic Circle is an engineering solution to avert the risks of narrowing crop diversity. The vault now holds more than 800,000 seed samples as an “ultimate insurance policy for the world’s food supply”.

I’m doing my bit for crop diversity too. Gardening after all, is cheaper than the psychological interventions needed to cope with hunger, and you get tomatoes. And as well as tomatoes, potatoes, corn and the other common crops I grow rarer treats like medlars, mizuna, okra, kale, rhubarb and Jerusalem artichokes. I save seeds too, and this has led me to favourheirloom plants to enjoy and maintain old cultivars that breed true.

And why is this the vegetable decathlon? Because I’m after the elusive first prize in the coveted “Group of Ten Vegetables” category at my local Braidwood Show. Second again this year.

How are you applying science in your kitchen and garden?

From the Sun to my Screens

By Su Wild-River

This post was first published at: http://nofunnybusiness.net/2013/12/from-the-sun-to-my-screens/

I recently completed a Massive On-Line Open Course (MOOC) called “Dynamic Earth” through the University of Toronto. And in case you are wondering whether science can be taught through MOOCs, consistent with the pedagogical analysis presented by MOOC providers, I’m giving you a glimpse into MOOC world here.

The course’s ‘peer reviewed assignment’ was a 300 word essay anonymously assessed by three other randomly selected students who have also received a marking rubric and examples of papers of varying quality that have already been graded by professors.

The topic for this assessment was to trace the likely path from the device on which we view MOOC study material, back to the original astronomical source of energy – ie some form of solar energy. Is this science? Is it science communication?

Here is my response to the assignment topic – from the Sun to my Screens

“Fossil fuels are an input to all of the devices that feed MOOC materials into my brain. Those devices include a computer at The Australian National University (ANU), a home computer, and iPad.

My computer at The Australian National University (ANU) and my home electricity system are connected to the Eastern Australian electricity grid (EAEG), which sources mostly coal-fired electricity. The coal is burned to release heat which boils water to turn turbines and generate electricity, which is then transported through the grid to my computer. The coal issourced from plants that grew 200-300 million years ago and used solar energy for photosynthesis, converting carbon dioxide to cellulose. They then compressed into coal due to overlying sedimentation in a process fuelled by solar driven wind and water systems. Burning coal for electricity is inefficient and releases terrestrial carbon dioxide back into the atmosphere, unbalancing the earth’s dynamic atmospheric system and causing dangerous global warming.

My devices are also powered by a small amount of hydroelectricity and wind energy with fewer damaging impacts. The wind occurs because the sun warms the Earth’s surface, particularly at the equator. The Earth’s rotation and Coriolis Effect drive a pattern of wind across the world. Rain captured in the Snowy Mountains hydroelectric scheme falls there because low pressure systems are blown across Australia by Southern Hemisphere Westerlies. Water evaporates from the Southern and Pacific oceans and is uplifted in the low pressure systems, cooling and causing precipitation as the lows spiral clockwise across the Snowy Mountain Range. The rain is stored in dams high in the landscape, and then released under gravitational pressure to turn turbines that generate hydroelectricity. The Westerly winds also power turbines within the EAEG, generating electricity from wind.

At home I use a desktop computer, and charge my iPad to access this MOOC. Most of that energy comes from a solar array on my roof. Solar electricity is a more sustainable alternative to coal-fired power because it uses solar radiation directly from the sun, and there is no additional atmospheric pollution once the systems are installed.

I also use by brain to access this MOOC. The final energy pathway is the food I eat to power my brain and body. I grow about a quarter of my own food, mostly using the glycogen and glucose produced in my body by my digestion of that same food as the power source. The other half of my food is shop-bought, and I try to keep the food miles and other fossil fuel energy inputs down by buying fresh and local, with minimal packaging. The plants that I eat use photosynthesis to transform sunlight, nutrients and water into delicious cellulose. My brain is digesting the course material, and instructing me to work at home, using my solar energy systems.”

I received 26 out of 27 from my peer reviewers – so I was pretty happy with that. I also received the comment “You’re not a student, are you? That is the best and most extraordinary answer I have read so far. Thank you and God bless!” which I found rather enchanting.

I was however, somewhat disturbed when it came to my training in how to mark others’ assignments. I was given three assignments to mark as a test run – to calibrate my marks with those of the professors. The first one received 8/9 from me, but only 3/9 from the professors. The MOOC program instructed me to review the rubric. The second was better. I gave it 3, and they gave it 2 but I was still asked to review the rubric. I thought the third example was logically flawed and gave it 2, while the professors gave it 9. The next screen congratulated me on completing my training and started directing me to mark others’ work.

I enjoyed the marking process although I was nervous about the quality of my marking. I marked one from a remote area of Russia, and was fascinated to read about the landscape, isolation and its impacts on energy opportunities, with nuclear and coal seeming the only realistic options. It reinforced the message that those of us with green-energy leanings in Australia parrot out all the time – there’s so much energy here that we have no real excuse to burn all of this coal.

What energy are you using to access this blog, and what are the alternative pathways from the sun to your screen?energy-transformations1-300x174

Writing plain English science into legislation; or Compost Eats Methane

By Su Wild-River

This post was first published at: http://nofunnybusiness.net/2013/12/writing-plain-english-science-into-legislation-or-compost-eats-methane/

Both legislators and scientists can struggle to communicate our work effectively in plain English. How much harder is it when we try to encapsulate science in a law? I’m facing this challenge at the moment, drafting a Carbon Farming Initiative methodology which if accepted, will form a regulation under the Carbon Credits (Carbon Farming Initiative) Act 2011.

The Carbon Farming Initiative (CFI) was introduced by Australia’s previous Labor Government, and is one element of Australia’s climate change mitigation framework that issupported by the current Coalition government. The program allows farmers and land managers to earn carbon credits for reducing or avoiding greenhouse gas emissions. CFI methodologies establish the rules for calculating credits confirming that they are genuine, permanent and additional to business as usual. To achieve this, the methodologies must beclear, unambiguous, complete and precise.

The methodology I’m working on is called Passive Landfill Gas Drainage and Biofiltration. In plain English, this means putting compost on landfills, because compost eats methane.

This methodology is in part a eulogy to much-loved environmental professional Mark Ricketts who died suddenly in 2011. Shortly before his death, Mark was advising me and my students on a project to estimate the carbon emissions and reductions from landfills when he told me to consider compost, and then earned giggles with stories of the insatiable hunger of compost greeblies and the yumminess of smelly gas.

I had previously worked alongside Mark while he was drafting the Queensland Environmental Protection Act 1994. I watched his optimistic daily trips to the parliamentary draftsman and his exasperated return to our office as he tirelessly negotiated for each sentence to be as simple and readable as possible. The result of his work is a plain English law that encapsulates the precautionary principle, ecologically sustainable development and other complex concepts based in science.

Drawing inspiration from Mark, my team’s CFI proposal was to design a simple, practical method which used robust science, while being easily understood by the hundreds of operators of small local landfills across Australia. Many of these good folk lack the time and capacity to read complicated laws, engineering equations or to establish scientific procedures for their monitoring and evaluation. But they can pick a winner and follow procedures.

Our methodology needs to be consistent with all related national and international methods, so I have read and reviewed hundreds of scientific papers on compost and landfills and the calculation of carbon emission reductions. Most emission reduction methodologies explain themselves through symbols and equations with the most relevant one having five solid pages of such equations, interspersed by just a few sentences for those of us without maths as a first language (pp2-6). Here’s an example:

Excerpt from CDMIIIAX

In contrast, our equations look like this:

 Net greenhouse gas abatement = quantity of methane that is oxidised by the biofilter – baseline emissions – project emissions.

Other strategies for keeping it simple include minimising the number of measurements and using simple, cheap and readily available equipment.

So far progress is good, and our focus on practicality and clarity is well received by the government and stakeholders alike. It was hugely satisfying when the non-technical member of our Technical Working Group smiled saying he found our draft methodology very readable.

Assuming the methodology gets approved, the next step will be to find project proponents. Unfortunately, this step is less likely to succeed. Australia’s initial carbon credit value of $23 per tonne meant that projects could have pay-backs in under seven years, and reap annual profits thereafter. A direct action approach delivering a carbon price of – say $8 would take over 50 years to pay back. The most likely outlook is an elegant methodology that will fail to feed any compost.

Am I the only one disappointed?

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