Spencer and Christy have amended their satellite algorithm. Here are some links and comments, courtesy of ukweatherworld. I anticipate that there will some huffing and puffing about this, but Hans Erren’s graph should keep matters in perspective.
The ukweatherworld discussion is here.
The updated satellite data is here with the following comment:
Update 7 Aug 2005 ****************************
An artifact of the diurnal correction applied to LT has been discovered by Carl Mears and Frank Wentz (Remote Sensing Systems). This artifact contributed an error term in certain types of diurnal cycles, most noteably in the tropics.
We have applied a new diurnal correction based on 3 AMSU instruments and call the dataset v5.2. This artifact does not appear in MT or LS. The new global trend from Dec 1978 to July 2005 is +0.123 C/decade, or +0.035 C/decade warmer than v5.1. This particular error is within the published margin of error for LT of +/- 0.05 C/decade (Christy et al. 2003).
We thank Carl and Frank for digging into our procedure and discovering this error. All radiosonde comparisons have been rerun and the agreement is still exceptionally good. There was virtually no impact of this error outside of the tropics.
Hans Erren posted up the following graphic at ukWeatherworld and his website to show the effect (Hans helpfully included the R-script)
One of the ukWeatherworld posters said: "The global decadal trend is now 0.123 K – similar to the surface data." I don’t think that this is the case at all. I’m not sure that statistically it makes a whole lot of sense to talk about "trends" to 3 significant digits in data with as much serial autocorrelation as this, but, leaving that aside, the difference between the Jones data and the satellite data (even after this adjustment) is much larger.
I haven’t updated the figure calculated last April and re-posted here, but you get an idea of the difference beween the satellite and Jones data. There is a big knock-on effect in this difference, because it is the difference that levers the detection-attribution studies.