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Thank you for the great response, certainly good stuff to think about. But I think I did not make myself clear. The RSS trop data shows there is a 1.2K/century

Thank you for the great response, certainly good stuff to think about. But I think I did not make myself clear. The RSS trop data shows there is a 1.2K/century trend. My interest was in "the pause" over the last ~20 years. So the metaphor becomes, imagine you were told the tide was coming in at a steady rate and that CO2 was causing it. Then for 19.5 years CO2 continued to grow at a steady rate, but the tide didn't come any closer during that period. That is certainly interesting in an of itself; and needs an explanation.

phaemon 11y ago
You made yourself clear. To follow the metaphor, if the increase in tidal levels over the past 19.5 years were significantly different to the increase in tidal levels over (say) the past 30 years then it needs an explanation. If they were not, then the simple explanation is that 19.5 years is not enough data to draw any conclusions. That's just how it works. You can't draw a conclusion from a lack of data. EDIT: Forgot to say: at the moment, what you are trying to show is that there has been no significant warming over the past 19 years. Your null hypothesis is that there has been no warming over the past 19 years. When what you're trying to show is the same as your null hypothesis, you're doing something wrong.
- curiousgeorgio 11y ago
  If merpnderp were to say the null hypothesis is that the longer-term trend (1.2K/century as stated) should continue as expected even into recent decades (or perhaps "correct" the data for that relationship because we're assuming it's not up for debate), then the data for the past ~20 years would show a departure from that hypothesis, would it not? In that case, the point being shown is different from the null hypothesis, and may be significant. Am I missing something?
  - phaemon 11y ago
    Nope, you're missing nothing. That's absolutely correct. The problem (from merpnderp's point of view) is that the data for the past ~20 years doesn't differ significantly from the 30 year (or longer) trend. It's using the lack of significance to mean something significant which is the root of the error.

phaemon 11y ago

You made yourself clear. To follow the metaphor, if the increase in tidal levels over the past 19.5 years were significantly different to the increase in tidal levels over (say) the past 30 years then it needs an explanation. If they were not, then the simple explanation is that 19.5 years is not enough data to draw any conclusions. That's just how it works. You can't draw a conclusion from a lack of data. EDIT: Forgot to say: at the moment, what you are trying to show is that there has been no significant warming over the past 19 years. Your null hypothesis is that there has been no warming over the past 19 years. When what you're trying to show is the same as your null hypothesis, you're doing something wrong.

curiousgeorgio 11y ago
If merpnderp were to say the null hypothesis is that the longer-term trend (1.2K/century as stated) should continue as expected even into recent decades (or perhaps "correct" the data for that relationship because we're assuming it's not up for debate), then the data for the past ~20 years would show a departure from that hypothesis, would it not? In that case, the point being shown is different from the null hypothesis, and may be significant. Am I missing something?
- phaemon 11y ago
  Nope, you're missing nothing. That's absolutely correct. The problem (from merpnderp's point of view) is that the data for the past ~20 years doesn't differ significantly from the 30 year (or longer) trend. It's using the lack of significance to mean something significant which is the root of the error.