Those wanting to reduce their contribution to climate change are generally presented with two options: cut back on your own emissions or pay someone else to do so. The first requires sacrifice and/or time and/or capital. You can give up flying, meat, and air conditioning; you can take trains instead of planes; you can invest in solar panels and ground source heat pumps. The second set of options is arguably more practically challenging and morally problematic. It is harder to verify that someone else has actually cut emissions, and done so in response to your payment rather than any other incentive. There are also those who think it unacceptable to buy your way out of taking action yourself.
There is, at least theoretically, a third option. Suppose I buy an area of land in British Columbia. The place is ideal for growing trees and the trees on the lot grow each year, absorbing carbon from the air in order to do so. As a result, my little forest is a net carbon sink. The danger, of course, is that the carbon will be re-released. Someone might cut down my forest. My forest might dry out or burn down (possibly because of climate change). Then, I will have accomplished little of value, given that carbon dioxide has a long atmospheric life. For most intents and purposes, it may as well never have been absorbed.
What I need to do is ensure the carbon doesn’t go anywhere. Here are some options I have come up with:
- Cut down trees at the growth rate (if one matures per month, cut one per month). This ensures that the forest will always be absorbing the same amount of carbon per unit time. Then, encase the lumber in something durable and air tight – keeping the carbon inside sequestered indefinitely. Then, either use the wood as building material or simply bury it.
- Cut down trees as described above and bury them somewhere they are relatively unlikely to decompose: such as a peat bog or the Arctic tundra.
- Cut down trees as described, chop them into chips, burn the chips for energy, capture and sequester the carbon dioxide underground. This approach has some variants: (a) seperate oxygen from air and burn the chips in that to produce gaseous outputs that are mostly CO2 or (b) convert the biomass chips into syngas (hydrogen and carbon monoxide) before combustion.
Of course, there are issues with all of these:
- Is it possible to shrink wrap wood in a way that will keep the carbon inside indefinitely? How many carbon emissions would be associated with making the shrink wrapping material?
- The Arctic tundra is melting, threatening massive carbon releases. Global temperature rise could do the same to peat bogs.
- This may require tens or hundreds of millions of dollars worth of capital and skilled labour, depending on how much all the equipment costs. Nobody could do this alone, though it may be possible to do at a commercial scale, partly in exchange for payments from those having their emissions offset.
None of these are great options, but they do offer at least the logical possibility of actually, literally offsetting one’s carbon emissions. For those with aspirations for world travel, but also serious ethical concerns about climate change, such options may prove the only choice.