Friday, March 13, 2009

Wool socks have carbon footprints

There have been several insinuations that the production of beef for food is particularly problematic with regards to greenhouse gas emissions. In addition to the resource cost associated with meat in general, beef is single out because cows allegedly generate a lot of methane, as a result of being ruminant animals.

This makes me wonder, where’s the outrage against other cud chewing creatures. There are plenty of other ruminants who seems to be getting a free pass here. For example, if a juicy steak is considered by activists to be a glacier-melting extravagance, then what is a wool sweater?

As of 2002, Australia had 100 million sheep, but only 26 million cows, a ratio of 4:1*. As the cows have greater total mass, the sheep contribution is probably half to a quarter that of cows, depending on the which numbers you pick. In NZ, where the sheep/cow ratio is higher, the little bleaters account for almost half of the country’s entire weighted emissions. And hamburgers cannot be replaced by a lighter, warmer substitute synthesized from recycled plastic bottles. So if you want to get serious about the ruminant problem, phasing out wool seems to induce a much smaller decrease in standard of living than reducing the cattle herd.

Of course, there are some people who simply prefer animal-based fibres to synthetic ones, just like many people prefer meat protein to squashes and beans. The links above suggest that switching from cattle to non-ruminant meat sources like kangaroo, pork, and chicken would provide a substantial benefit. There is no reason that lovers of animal fibre clothing cannot do the same. After all, rabbits aren’t ruminants. Neither are foxes or mink. So getting all those woolen clad activists to switch to fur coats would probably reduce anthropogenic methane emissions.

So next time you see someone decrying beef stroganoff and large clunky American cars,** check out their threads. Because wool socks have big carbon footprints.

* As the current drought is more severe in sheep country than cattle country, this ratio may have dropped since then.
** Is there another kind?

8 comments:

Anonymous said...

I'm so going to use this argument against people who complain about the carbon footprint of everything you use/eat/etc., thanks.

Hank Roberts said...

Wait, do sheep get fed corn, like feedlot cattle and chickens? That's the source of fossil carbon for those animals.

Sheep are troublesome, they'll eat plants right down to the roots if not moved often.

Chuck said...

Here in Australia, cattle spend relatively little time in feedlots. Ditto with most other tropical export countries.

Silver Fox said...

Great post (as per usual)! I've been allergic to wool for a long time, and prefer synthetics and fur. Fur is especially acceptible in Alaska.

Anonymous said...

I agree with you on the whole, but would like to point out that you can only eat a cow once. Wool grows back.

Chuck said...

And do sheep stop farting, burping, and respiring between shearings?

John Williams said...

Thought provoking post. Raises more questions though.
If sheep are not farmed, then crops or grass will be grown anyway. At the end of the growing season the grass dies off and generates CO2 and some methane. The crops will be harvested and eaten and also generate CO2 as they are digested. Of course methane is a more potent GHG but has a half life of 2 years in the atmosphere, as it breaks down to CO2 in the presence of oxygen.
So in all eventualities the crops return to CO2 which the next seasons plants absorb. Crops and animals grow each year while artificial fibres are produced from fossil fuels which are finite in nature and therefore not sustainable.

John Williams said...

Thought provoking post. Raises more questions though.
If sheep are not farmed, then crops or grass will be grown anyway. At the end of the growing season the grass dies off and generates CO2 and some methane. The crops will be harvested and eaten and also generate CO2 as they are digested. Of course methane is a more potent GHG but has a half life of 2 years in the atmosphere, as it breaks down to CO2 in the presence of oxygen.
So in all eventualities the crops return to CO2 which the next seasons plants absorb. Crops and animals grow each year while artificial fibres are produced from fossil fuels which are finite in nature and therefore not sustainable.