Developed and developing nations have agreed that global temperatures should not rise more than 2C above 1900 levels, a G8 summit declaration says.Now, my Inner Geek wants to make it clear from the outset that atmospheric physics is not his field of alleged expertise. He makes his living trying to herd electromagnetic waves in the general frequency range of 7E+14 to 2E+13 Hz toward useful destinations, using optical technologies. My Inner Geek, however, is not here to propose any crackpot pseudo-theories of his own. He just has a few humble questions for Our Great Leaders:
That is the level above which, the UN says, the Earth's climate system would become dangerously unstable.
US President Barack Obama said the countries had made important strides in dealing with climate change.
1. O Great Leaders, how many of you are atmospheric physicists?
2. You have declared, O Great Leaders, that "global temperatures" must not rise by an amount, specified in one significant figure, from what they were at a date containing a glorious two significant figures. May I be pardoned, O Great Leaders, for wondering, with some skepticism, just how rigorous a calculation produced your specification?
3. Just exactly what, O Great Leaders, must be measured in order to produce the quantity you call "global temperatures?" Please tell us: exactly what temperatures are these? How, exactly, are they to be combined to determine when a 2C° increase has occurred? In fact, what were those "global temperatures" in 1900, and what is the uncertainty in your knowledge of this value? May a humble Inner Geek see your analysis, on which that unspecified uncertainty is based?
4. Why 1900, O Great Leaders? Was there something uniquely garden-like about Planet Earth in that year? Why not 1970? Or 1950? Or 1800? 1066 was a memorable year, was it not? Or 1588? Mightn't 1,000,000 BC be even more suitable? (I think Racquel Welch appeared in a film with that title, and she's awfully good-looking, in this humble Inner Geek's opinion.)
5. "Dangerously unstable," you say? What -- is our climate safely stable today? Was it in 1900? What's the definition of these terms? What is it that happens at delta T = 1.6 C° (that would be 2 C°, to one significant figure) that doesn't happen at delta T = 1.4 C° (1 C°, to one significant figure).
6. O Great Leaders, can you show me what your climate model predicted, ten years ago, that "global temperatures" (whatever that means) should be today? And what is the difference between your model prediction and what we actually have? And don't fudge, now. I can always tell when you actually have a bunch of model predictions, of which most or all are wrong by several degrees. It's something in the way you won't look me in the eye.
Gentle readers, I don't think I'll hold my breath while waiting for the exalted heads of the G8 to answer my Inner Geek's questions.