Thursday, June 18, 2009

Portland's Greenhouse Gas Emissions

I am forever trying to give Portland (OR) the benefit of the doubt on their claims about climate change, but almost every time I start to read something they've written they seem dubious almost immediately.

Here's the latest example. In the Executive Summary of Portland's Climate Action Plan 2009, page 9, they give their greenhouse gas emissions and population:

Total Carbon Emissions (mt):
1990: 8,875,739
2007: 8,809,630

1990: 584,000
2007: 702,000

I'm sorry, but as soon as I see such numbers I know the author hasn't a clue what they're talking about and the report is probably meaningless.

You just cannot measure Portland's emissions to seven significant figures. You can't.

With the population numbers they at least show a reasonable uncertainty of about 1 part in a thousand. But not for the emissions numbers. Are they seriously trying to tell me that they know for sure that Portland's 1990 GHG emissions were 8,875,739 mt and not 8,875,738 mt or 8,875,740 mt?

Maybe you know they were 9 Mmt. Maybe even 8.8 Mmt. I can't reasonably grant you much more accuracy than that.

In other words, someone just ran some big computer program and write down what it spit out, without even bothering to think about what it means. It looks stupid. It eliminates their credibility. It's not something anyone who knows even the least bit about science or mathematics or engineering can take seriously.

Why do they do this? You would suppose the the City of Portland is hiring smart people with college degrees. Is this what they learned in college? Really?

I'm sorry, and maybe I'm just a snob, but I was educated that, when you make a mistake like this right up front, everything else you say is tainted.

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