Wednesday, 23 May 2007

carbon costing

Knowing where and how to start calculating the carbon cost of making batik... that's something I've been pondering for some time. I feel the onus is on primary producers and suppliers to give the carbon cost of their produce and products - from which the true cost of making batik can be deduced.

Despondently I've thought that time is some way off, especially if buying from small scale producers. These individuals seem unlikely to have the time/money/know-how to calculate their own carbon cost... or so I thought until today, when Gossypium's latest e-newsletter arrived. Gossypium is a major importer and retailer of organic fair trade cotton clothing and textiles from India. It says

"Enough cotton for a t-shirt requires 2 square metres of land and will take 8 months to grow. In that time the cotton plants will absorb 3 kg of CO2 while growing. The t-shirts will travel 9,500 km by sea, emitting 0.002 kg of CO2 per t-shirt."

(in old money, that's 21.5 square feet, 8 months, 6.6 pounds, 5,900 miles, and 0.004 pounds)

But before I start skipping joyfully (spilling wax in the process) thinking using-cotton is assisting with reducing carbon emissions, I need to compare these CO2 absorption rates with an alternative crop on that 2 square metres of land. And with not-growing, ie leaving it fallow; and with the land being left in its natural state. (There is no comparison to make with so-called conventional agriculture with its nitrogen-based fertilisers: nitrous oxide, produced during cultivation, is another main greenhouse gas).

Cotton agriculture: I believe cotton plants are sown/planted each year rather than cropped year after year. Whichever, what happens to the 8 months of absorbed carbon after the plant is uprooted, ploughed back in, fed to livestock or whatever? Is it re-released to the atmosphere - even if for only 4 months until the next 8 month absorption starts? Or does that re-absorption count as a permanent lock-up of carbon, for as long as cotton is grown on that 2 metres?

And balancing the needs of the world's t-shirt wearing population and sustainability, how long must my t-shirt last before my turn comes up to have another from that 2 square metres? Can that two metres worth clothe the world's over-population?

I've a lot of respect for Gossypium, especially for publishing the carbon figures. I'm sure they wouldn't have "spun" them just to look good... but there's a bit more to find out yet.

Something else I've been pondering... a scientist who could help me with the carbon, chemical and more-besides understanding is becoming a necessity. I know my limitations!

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