ChristopherWhite.info

Current methods of producing biofuels release so much carbon that it could take hundreds of years for them to make any greenhouse gas savings, a recent study has found.

Research led by David Tilman from the University of Minnesota has shown that whether biofuels offer carbon savings depends on how they are produced. Converting heavily vegetated land such as rainforest, savannah or grassland in Brazil, the US and southeast Asia can release between 17 and 420 times more CO₂ than the annual reduction in emissions provided by using biofuels in place of fossil fuels.

Growing demand for alternatives to petroleum is increasing the production of biofuels from food crops such as corn, sugarcane and soybean, with both agricultural land and native ecosystems being converted to biofuel production. The soils and plant matter on this land are large stores of carbon, and together they contain almost three times as much carbon as is found in the atmosphere. Converting the land to grow crops for biofuel manufacture releases this as CO₂ via burning or decomposition.

After these initial emissions, there is a prolonged release of greenhouse gases as roots and branches decay. The amount of CO₂ released over the first 50 years of this process is the ‘carbon debt’ of land conversion. Biofuels made from crops grown on converted land can repay this carbon debt if the net greenhouse gas emissions generated by their production and combustion are less than those of the fossil fuels they replace, but in many cases this may take centuries.

Tilman and his colleagues estimated the time taken to repay the carbon debt of biofuels produced from various crops and habitats. They found that only two would pay off their greenhouse gas emissions in under 50 years – sugarcane ethanol and soybean biodiesel, both grown on converted Brazilian Cerrado savannah, have repayment periods of 17 and 37 years respectively.

Most repayment periods are far longer, rising to an estimated 420 years for palm biodiesel grown on converted tropical peatland rainforest, as the required drainage causes additional emissions due to peat decomposition. There is also a 48-year repayment even when converting farmland that has been under the US Conservation Reserve Program for 15 years, as such systems gradually recover their carbon store.

In fact these figures may be an underestimate, since the researchers assumed cleared land to be in a fixed state, whereas it could still be accumulating carbon. In this case, the debt would be increased by loss of future carbon storage.

The production of biofuels must release as little stored carbon as possible if they are to successfully mitigate climate change. Biofuels made from plant waste, or native perennial plants grown on abandoned agricultural land, create little carbon emissions and offer immediate reductions in greenhouse gas generation, as well as reducing the displacement of food crops that causes the price of food to rise.

However landowners may prefer land clearance that results in greenhouse gas emission if they can make a profit producing biofuels but do not receive payments for carbon management.

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I don’t normally write posts about humorous search terms.

But to the person who stumbled across this site by googling “computers web internet”: welcome to the modern world.

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Matthew’s best internet prank yet?

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Well, not quite. But…

My screensaver does clever things — it downloads data and analyses it to contribute to a couple of science projects, almost justifying not bothering to turn my computer off ever. I imagine it’s doing it now. I don’t know.

One of the projects is a climate change model, from which the following are two screenshots. Spot the bullshit:

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The Identity and Passport Service has rather a handy contact form for members of the public to ask questions about the planned ID card scheme (and I do mean scheme).

I used it to submit a query[1] on September 29.

They responded today - to the wrong email address. (The usual .co.uk as opposed to .com thing.)
This is the text of my follow-up query:

You responded to my last enquiry to the wrong email address. If you can’t even get someone’s email address correct when they’ve typed it in a box for you, how do you reasonably expect to be able to run a National Identity Register successfully?

I’m not expecting a response.

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[1] I was wondering whether there’ll be some sort of security procedures put in place to detect fraudulent attempts by an individual to register twice with the same biometrics, and how that will affect those who legitimately need a new identiy (eg people in witness protection schemes, members of the intelligence services). “Special arrangements” will be made, apparently. I bet they work…

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This:

is not real.

It had me fooled, briefly.

It was created using POV-Ray software, a program that was originally open-source, created by amateur programmers, on an Amiga machine, and then ported to the PC. It’s an example of something I mentioned on the old blog: high-end computers being responsible for some lazy programming, with developers over-relying on hardware. The fact that this was developed on a low-tech computer meant it had to be as efficient as possible, and can now make better use of newer technology.

(I used to do some 3D graphics stuff when I was a kid. I was - needless to say? - Not Very Good. An inherent tendency to geekiness doesn’t compensate for lack of talent.) 

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From the ICT Usage Policy at work:

“Due to the lack of privacy it is important that nothing is contained within an e-mail, which could potentially be considered as offensive…”

Yes, I’m sure it could.

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1. Or, alternatively, ‘The importance of ignoring the grammar checking tool on microsoft word’.

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