Friday, April 13, 2007

Half-Life

The cover story for the May-June edition of Mother Jones magazine reads “In 93 years, half of all life on Earth will be extinct. So what?” The estimate is based on calculations by esteemed biologist E.O. Wilson.

I used my consumption model to determine under what conditions the prediction would be true (and to further test the model). The result was jaw-dropping, after I fixed the feature that is supposed to reduce consumption by a fixed amount the first year after changes start. According to my model, the Living Planet Index (which measures the average population sizes of all species) falls to 48 percent of its 2006 value in 2100 if next year the global footprint drops to less than one percent of its current value and then resumes its three percent annual growth until at least 2100. That is, my model suggests that Wilson’s prediction is based on current annual consumption that is less than one percent of its actual value. The model shows that starting with the actual consumption we could reach the half-way mark much sooner, by 2011.

1 comment:

BradJ1001 said...

For an excellent list of links to information about the sixth great extinction, see: http://www.well.com/user/davidu/extinction.html