A student asked me to comment on the Dakota Access Pipeline, based on my area of expertise. This (in a slightly edited form) is what I wrote:

It is not possible to detect the climate change caused by any particular piece of our energy infrastructure, yet in aggregate the greenhouse gas emissions from energy infrastructure is having a tremendous impact on our climate system.

The question, therefore, is not about the amount of climate change caused by this individual facility, but what environmental and human damage will result as a consequence of building more such infrastructure.

From a global environmental perspective, the Dakota Access Pipeline is another step down a path we shouldn’t be going down. No one step down this path brings calamity, but each step increases risk and increases damage, and collectively many such steps could prove catastrophic.

If we know we need to be transitioning to the near-zero emission clean energy system of the 21st century, why are we continuing to expand last century’s archaic polluting energy system?

Clearly, there is money to be made by building this pipeline, but the public interest lies in building the energy system of the future, not in enlarging the energy system of the past.