Yes, I called it a saga, because that’s what it is going to be. Other than grammatical errors, the first criticism to Watts et al is that they didn’t account or even really address the TOB (Time of OBservation) biases.
It isn’t that it was necessary for the work to be valid, the work is valid. It’s just that there’s much more to the story than sighting. In my travels throughout the internets, I’ve found criticisms such as this to be fairly typical…… (stealing a comment from WUWT) Bold mine.
In the Fall, Watts, Nielsen‐Gammon, Jones, Niyogi, Christy, and Pielke Sr paper (2011), in Figure 4, the trend in the raw data is about 0.2°C per decade. The trend in the data corrected for differences in the time of observation is 0.3°C per decade. (The rest of the homogenization does not change the mean temperature much.)
Thus the difference between the trends in the raw data and the one in the homogenized (adjusted) the manuscript Watts et al. (2012) found are most likely due to forgetting to correct for the time of observation bias (TOB). This is an important issue, which is why McIntre [sic] is having some doubts about the manuscript.
As http://rabett.blogspot.de/2012/07/bunny-bait.html points out: “There is practically no time of observation bias in urban-based stations which have taken their measurements punctually always at the same time, while in the rural stations the times of observation have changed.”
Thus the differences in the trends for the different station quality classes are likely due to forgetting to correct for the TOB. Another likely problem with the analysis of Watts et al. (2012) is that the classification of the stations was performed at the end of the study period. Stations that were poor at the end, but average in the beginning will show an artificially stronger trend.[editor: presumably, stronger towards a higher temp] Similarly stations that were good at the end, but average at the beginning will slow a weaker trend (or even negative trend). This selection bias may well explain the differences found in the trends for the various quality classes. The very least, these are issues, which a rigorous scientific paper would discus.
For now, I will not study this manuscript any further, expecting that it will never be submitted. If it is, I am happy to review it more closely, knowing how much Anthony Watts likes blog review.
So, what’s to be done about this criticism? Well, nothing……. no, not really. First of all, everyone should laugh. We should laugh at several things.
Without analysis or numbers or even reading any papers, first laugh at the assertion of vvenema ….. no, I didn’t say laugh at the name!!! Laugh at this….
McIntre [sic] is having some doubts about the manuscript.
I wonder if it is lost on these people about doubts and assertions and truly knowing something. You truly know something by faith and faith alone. All else is subject to doubt. I will expound if asked, but for the sake of brevity, I hope most here will understand this. If not, ask away! Steve McIntyre is simply being Steve McIntyre. And, I’ve no doubt his contribution will make the paper even more robust, and in all likelihood eliminate even more spurious warming. So, laugh at these people they think something is awry for the wrong reasons. Something is awry, but it is going horribly wrong for the alarmists.
But, the laughs shouldn’t stop there. One of my favorite places to laugh at is the rabbit run or whatever. It’s complete with 3rd person references and people who claim to be bunny rabbits or something. I’d call them furries, but it may insult the furries and/or the bunnies, or maybe they’re one and the same, so I’ll just leave it at that.
Eli (Dr. Hapsomething) seems to think stations improve themselves. (4th para of the critique) It’s like when my lawn takes care of itself. He seems to think the USHCN would originally placed a thermometer in some real crappy location, but then the site improves over time. (Editor note!! This does happen in the land of unicorns, sadly, not so much in real world.)
But, let’s get to the real critique. The TOBS bias.
“the trend in the raw data is about 0.2°C per decade. The trend in the data corrected for differences in the time of observation is 0.3°C per decade.“
For those confused by the vernacular, this is stating that there is a difference of 0.1°C/decade of warming which wasn’t properly accounted for in the raw temperature readings.
Watts et al states, “The Raw Tmean trend for well sited stations is 0.14°C per decade lower than adjusted Tmean trend for poorly sited stations..”
So, this is how warmist Eli and the rest of the warmista are considering this. ‘Watts found that simply measuring the raw data based on sighting issues it found 0.14°C per decade of spurious warming, but after considering TOB bias, most of that warming is eliminated’.
I suppose if you were a sophist such as the warmista, then this is the way you’d consider this. In which case, then Watts et al would have only found 0.04°C/decade spurious warming. Which, by itself, wouldn’t be a major accomplishment but, could add to the greater discussion.
But, we’re not sophists. The error in the thinking is that the TOB adjustment would be the same across the board for the sighting ratings or even more for the rural stations. (Urban settings should have better compliance for TOB) I don’t know the answer to how much bias would be to what rating. But, as shown above, a very notable statistician is looking into it.
Here’s the way I see it. If one is going to look at this in this manner (see final thoughts) then there is a hierarchy of application. First, remove all but the well sited stations. Then look for the TOB bias. I suspect, we will not see a 0.1°C/decade raise in the data. We should see a lowering. The confusion comes with the perception of what a “rural” station is vs an “urban” station. It is assumed rural means a better sited station, and this is true to a point. But, if we read Watts, we see airports. Many, if not most, would have a rural rating, but would not rate as a 1 or 2 on the standard set forth by Leroy (2010). Beyond airports, rural doesn’t mean “no structures or heat sinks”. These too, would be removed from the original hierarchy filter.
Final thoughts: What I’m hoping to do here is to get people thinking about how to assist Anthony and friends. Give them proper critiques. I don’t necessarily put much stock in temp readings. It is true that we should, over time, see a zero trend. Heat is not confined to our surface. Heat is not energy. But, it is a function of energy. So, take what I’ve offered, mull it around, and then go after Watts et al. The TOB may not be the proper avenue, if you’ve something to offer in that respect go to Anthony or Steve Mac. The self-healing sites? …… well let’s let the warmista’s have that one in unicorn land. The discussion paper is just that, a discussion paper.