lawnmower vs sheep : The Kyoto folly

OPINION Lawnmower vs sheep: the Kyoto folly ROBIN GRIEVE 7/11/2008 12:20:00 PM NEW Zealand’s Emission Trading Scheme was devised to comply with the Kyoto Protocol. The Kyoto Protocol was devised to combat global warming. The idea is that a country’s carbon emissions are measured, or guessed, in line with clear rules laid out in the Kyoto Agreement. If that country emits more carbon than it did in 1990 it pays a penalty to another country that emits less carbon than it did in 1990. A country like Zimbabwe would be a country that emits less carbon and, if it was a signatory, would receive hundreds of millions of dollars from the New Zealand taxpayer. I’m sure this would be of great benefit to them. While this does nothing to reduce global warming, a country like Zimbabwe does benefit by getting a whole lot of our money. Not the sort of scheme an intelligent person would sign up to, you would think. In defence of the nameless one who did sign the agreement on our behalf, they actually thought at the time that New Zealand would get paid by other countries because we were clean and green. Sadly, they had made a bit of a mess of their adding and it turned out the money they thought we would get became money we had to pay. It was a billion-dollar mistake, but who are we to judge? This aside, Kyoto was cleverly worked out to measure and guess all the carbon emissions that were contributing to an increasing carbon level in our atmosphere. The correlation of the carbon level in the atmosphere and the globe’s rising temperatures was graphically illustrated in that discredited graph in Al Gore’s movie. This was seen by some as proof of global warming and by others as a discredited graph. Regardless though, of which one of those you are and regardless of whether this Kyoto deal is needed at all, one thing that should be indisputable is that what is good for the planet, as determined by Kyoto and its rules, should, in fact, be good for the planet anyway. . To my surprise, in an experiment I have named “Lawnmower versus Sheep”, I have found that Kyoto’s rules are in fact not good for the planet at all. The purpose of the experiment was to determine what is better for the planet, cutting my lawn with a lawnmower or grazing it with a sheep. I have defined “good for the planet” in terms of greenhouse gas emissions and by association any global warming that may result from me mowing my lawn. I usually notice the globe is considerably warmer after I have been mowing my lawn but it usually cools down quite quickly afterwards and I have never been too concerned about it. The lawn is 1000sq m and is cut at a height of 7cm down to a mown height of 3cm. LAWNMOWER A lawnmower is 460mm wide and with an average walking speed of 3kph while pushing a mower it means it would take 0.72 of an hour to mow 1000sq m. Because there is a bit of manoeuvring required around plants and the odd garden gnome on my lawn, I have assigned a mowing time of one hour. A lawnmower uses about one litre of fuel an hour. One litre of fuel burnt in the lawnmower adds 870gm of carbon or 3.107kgs of CO2 to the atmosphere. That is the environmental impact as measured by Kyoto rules of using a lawnmower. SHEEP Eating the lawn down from 7cm to 3cm is equivalent to removing 720kg DM/ha, or 72kg DM on my 1000sq m lawn. A sheep emits 13gm of methane/kg DM eaten. Therefore, a sheep eating 72kg DM off my lawn emits 936gm of methane. Methane, according to Kyoto rules, has a global warming effect 21 times that of carbon and such emissions must be multiplied by 21. 936 grams methane multiplied by 21 equals 19.65kg carbon equivalent. The environmental impact of my sheep, as defined by Kyoto, is 19.65kg carbon equivalent compared with a lawnmower’s 3.107kg carbon. This means my sheep is 6.3 times worse for the environment than a lawnmower according to Kyoto. Even if the extra exertion required to mow a hilly part resulted in some wind being broken on my part, the extra methane would not come close to closing the gap between the lawnmower and the sheep. ANALYSIS Any assertion that it is better for the environment to use a lawnmower than a sheep is clearly absurd and demonstrates the folly of blindly following Kyoto rules. My critics are right in their analysis of the greenhouse gas effect of methane and carbon, but their narrow focus blinds them to the blatantly obvious. That is, if you fail to distinguish between sustainable methane emissions from a sheep, and non-sustainable emissions from a lawnmower, you end up in the ridiculous position of having to argue that using a lawnmower is more environmentally friendly than using a sheep. However, when you can understand that a sheep only recycles carbon, while a lawnmower adds new carbon to the atmosphere you become a lot less ridiculous. As an aside, I did discover that all the main manufacturers have stopped making two-stroke lawnmowers because tough emission laws in the United States have outlawed them. So because we can no longer get these highly polluting lawnmowers from these manufacturers we, in clean and green New Zealand, import Chinese-made copies because it seems we don’t care about lawnmower emissions as much as the US does. The US does not support Kyoto and that, along with their lawnmower policy, demonstrates an intelligence we can only envy. Kyoto is a folly, and if we want to be a country that is clean, green and intelligent we should be worrying about the emissions from our cheap Chinese lawnmowers not our sheep. rrgrieve@xtra.co.nz