This post originally appeared on Sightline Daily.

The planned Keystone XL oil pipeline has earned major national attention for the damage it would do to the climate. At the same time, another climate drama is playing out with much less attention as coal companies make plans to export huge quantities to Asia by way of Pacific Northwest ports. It’s pretty clear that both projects are environmental horror stories, but I’ve been wondering: Which one is worse?

So, from the King Kong versus Godzilla files, here’s my analysis of their carbon impacts.

Chart.

The result surprised me: Coal exports look to be an even bigger climate disaster than the pipeline. There are, in fact, quite a bit more direct emissions from burning the coal than from the oil. That’s true even when one counts the energy-intensive tar-sands extraction and processing — and, of course, there are plenty of upstream emissions associated with coal mining that I’ve left out of the equation here. (In order to make a roughly direct comparison, I also omitted emissions associated with both products’ mining, refining, transportation, and so forth.) Clearly we can ill afford either one of these projects, but until we have a clear energy policy that respects climate science we’ll be wrestling with these kind of killer projects one at a time.

Now, for all the energy and math geeks out there, here’s the methodology I used to generate these numbers.