Post by duwayne on Apr 16, 2019 17:51:34 GMT
Just followed your note from "Global warming temperature predictions"
I too follow AMO Index against HadCrut
(I have tried to post the above as an image, but don't seem to be succeeding)
Like you, I have superimposed both images using Wood4Trees
My plot shows rising trend of Global Temperatures against AMO Index
I seems to differ from your plot above because I have not used "detrend"
Can you please explain why you used "detrend"
Neilhamp, that’s a good question. The short answer is that I detrended the Hadcrut anomalies because I am comparing them to the AMO which is reported as a detrended number. (The AMO signal is usually defined from the patterns of SST variability in the North Atlantic once any linear trend has been removed.)
Here’s the longer answer.
My quest is to try to predict how much the earth will warm over the next several decades if atmospheric CO2 continues to increase. I want to do this without relying on climate models which are based on highly unreliable weather models.
The short-term daily global temperature movements are random.
Most of the monthly temperature changes and trends over any given 5 year period can be explained by ENSO. Any CO2 warming effects are overwhelmed in the short term by ENSO.
If one uses 7-year smoothing, the longer term trends become more apparent. For periods of 60 years or so, there is a clear uptrend which probably is due, at least in part, to CO2.
If this long term uptrend is removed from the Hadcrut numbers, one is still left with a significant up and down oscillation. This has a period of about 60 years - 30 years up followed by 30 years down.
The AMO has a similar oscillation so I then compare this detrended Hadcrut chart to the detrended AMO chart to see if there is a correlation of oscillations.
My conclusion is that much of the change in global temperatures over decadel periods is due to the naturally occurring AMO (and other related ocean current oscillations).
Neilhamp (and others), I can never tell whether my explanations are understandable, so let me know if this is clear even if you don’t agree with it.