Ground vs Sat Covariance Plot
Posted by Jeff Condon on January 24, 2009
From my last post on temperature trend, I showed that there is a short term signal in the satellite data which has a higher rate of change than the ground data while the ground data 30 year trend is higher than the satellite data. Both are substantially different in trend yet models predict the UAH satellite trend should be 1.2 time GISS. Dr. Christy hypothesized that long term temperature trend has a negative feedback mechanism not accounted for in the models. If that were the case we should be able to look at various frequencies and their relative magnitude to see that UAH is higher than GISS at 2 years and as we approach the longer annual frequencies, GISS would trend higher than UAH.
My last post on this was
The crux of the matter is this.
1 – short term 5 yr trends on sats are greater than GISS
2 – longer term trends 30 year from sats are less than GISS
3 – models predict both trends MUST be greater than GISS
4 – All data sets have problems which have supposedly been corrected for. Which is correct, uah, giss or model. Somebody has a serious problem.
Dr Christy is looking to the models.
For this graph I used detrended data. It is the ratio between UAH and GISS with various degrees of filtering.
The graph is GISS/UAH covariance at various filter levels. It has meaning in that if the data is filtered by a gaussian function 3 years in width the data achieves a maximum variance of UAH ~ 1.15 to Giss ~ 1. After that the data trends back downward. This is expected if the models are in error and there is a missing longer term feedback in the model projections. I can extend the graph but it has no meaning since I detrended the 30 year data so it is forced to drop to a level of 1:1.
What’s interesting is first that high frequency data near 0 tends towards the zero level indicating a random process which in this case is GISS monthly noise as the Sat data is more smoothed. The second thing I notice is that the data peaks at 3 years and trends back downward to the 30 year trend of 1.
I have some FFT plots as well but they will need to wait until tomorrow.