Technically, I am a “climate scientist” ( atmospheric physicist, long retired) but I find myself turning more and more to your stuff for the excellent graphs and penetrating summaries so useful in my current role… that of writing for the layman. We both know that every time someone hauls out the Stefan-Boltzmann equation and starts turning the mathematical crank handle, most folks eyes start to glaze over. Summarizing the vast amount of new climate information into a form the general public ( and our government policy makers ) can understand is a daunting task, indeed… and you are frankly quite good at it.

I was thinking of volunteering to pay a visit to my nearest USHCN recording station in Cornwall, Vermont, but I see someone has already beaten me to it. Your project to shed more light on the results these stations have been producing is a valuable research project, and like it or not, you have morphed into a genuine climate scientist - and project manager, at that.

Along those same lines, are you familiar with a possible alternate temperature data set related to another network of weather sites used for aviation? These reports, known as hourly Meteorological Actual Reports METARS, are safety critical, so they need to be accurate.

The observation equipment is usually placed out of direct influence of buildings and airport surfaces (for safety). There is doubtless some UHI effect for some airports, but airports are large areas and often on the outskirts of towns and rarely inside the urban areas. The records for many of these airports reportedly go back at least 50 years and sometimes more and are to a global International Civil Aviation Organization ( ICAO) standard.

Wouldn’t it be interesting if we could track down some of the METARS historical data and compare it to at least a few nearby USHCN stations on a given day at the same time?

Just a thought. I haven’t a clue as to where the METARS historical data is stored, we might hope it is out there somewhere. As if you didn’t have enough on your plate already…

Best Regards,

Jim Peden

REPLY: Thanks Jim, its my TV meteorologist training. It was always my job to take complex concepts and make them understandable to the layman in under 3 minutes.

REPLY: I haven’t finished it yet, other pressing matters in the last week.

However, until there’s proof that any of the alarmist scenarios can occur, I’m not willing to pay attention to them. If we thought when building huge cities in coastal areas that the sea would be ever-static, then we’re, as a species, ignorant. The same way now if we think that global climate will ever be static or “normal” then we’re ignorant.

This whole debate needs to be re-booted. Is the planet getting warmer … YES or NO? That’s the easiest question for science to answer definitively. If YES, so what? As human beings why should we care?

Is it the warming itself that concerns us? Or is it the potential effects of the warming on human civilization? I suggest it’s the latter. And if it is, then why do we care what’s causing the warming? The effects don’t care.

If the ice is going to melt … if the seas are going to rise .. if the weather patterns are going to change because the planet is getting warmer, then these things will happen regardless of what’s causing the warming.

If the IPCC and Nobel Laureate Gore issued a joint statement tomorrow saying, “We were wrong. Human activity is NOT a significant cause of global warming. But the planet IS getting warmer,” what should we do?

Do we shrug our shoulders like Ms Litella and mutter a collective “Nevermind”?

Or are the potential effects of global warming on human civilization — regardless of its causes — still an issue to be reckoned with?

Because we don’t fully understand what causes hurricanes or how to stop them, do we therefore not concern ourselves with mitigating their effects on human beings?

Sure, it moves the zero point. How can anyone expect anything but a different histogram then? (Or rather a similar histogram with the X axis shifted somewhat.)

I don’t know what happened though since the histograms look very different (look at the two first UAH ones). The adjustment should be just minus or plus a constant.
Of course, the histogram bins are located in slightly different places then but still, the changes are quite drastic.

Of course, the original post, Part 1, with the different baselines were different and thus the histogram zeros were all over the place, you said this of the GISS data for example:
“Here, we see a much more lopsided distribution in the histogram. Part of this has to do with the positive trend, but other things like UHI, microsite issues with weather station placement, and adjustments to the temperature records all figure in.”

If you are an honest person, you could state that you were completely wrong in the above sentence.

In the very least the mistake was that you published part 1 and claimed GISS has errors, before doing part 2 which showed that this is not the case, but you had made an error in the data comparison.

People make mistakes, but most are a little more humble and think for a while that they have perhaps done something wrong themselves and don’t go publishing and claiming someone else is wrong instantly if they discover something that looks funny. Be especially careful if you are an amateur trying to correct professionals and check your work a few times and perhaps ask even someone to review it, or at least use a good tone when publishing. Then maybe your learning effort is taken at more face value.

REPLY: Interesting how you can’t wait for part 3, and immediately say “If you are an honest person….”

and dscott replied:

Interesting, are you saying it is actual measuring the physical surface? Because if you are, then there is a problem which such a measurement as a proxy for the air above it. [...]

Yes, basically. Unlike the MSU/AMSU microwave channels, the thermal infrared channels on AVHRR that are used to estimate SST are basically responding to the temperature of the ocean surface itself, not the air temperature. So one might wonder why the surface temp records would combine air temperatures (over land) and SSTs (over the ocean).

The short answer is that air temperature measurements over the ocean are still rather sparse, at least in comparison to the ease of measuring SST wall-to-wall via satellite. At the same time, while you’re right that the surface temperature can depart significantly from air temp, particularly as a function of wind speed … it turns out that this doesn’t matter all that much when you’re looking at temperature anomalies integrated over longer periods of time.

In other words, it wouldn’t make sense to try to calculate some instantaneous temperature product by combining air temps and SSTs, but studies have shown that over months/years the trends in the two types of measurements are comparable, even if the absolute values aren’t.

There’s a brief comment on this in the FAQ at the Hadley Center website:

Over the ocean areas the most plentiful and most consistent measurements of temperature have been taken of the sea surface. Marine air temperatures (MAT) are also taken and would, ideally, be preferable when combining with land temperatures, but they involve more complex problems with homogeneity than SSTs (Rayner et al., 2003). The problems are reduced using night only marine air temperature (NMAT) but at the expense of discarding approximately half the MAT data. Our use of SST anomalies implies that we are tacitly assuming that the anomalies of SST are in agreement with those of MAT. Many tests show that NMAT anomalies agree well with SST anomalies on seasonal and longer time scales in most open ocean areas. Globally the agreement is currently very good (Rayner et al, 2003), even better than in Folland et al. (2001b). However, some regional discrepancies in open ocean trends have recently been found in the tropics (Christy et al., 2001).

The emission curve looks very much like the emission of IR at 667 cm-1 (15 micrometers) There is a flat bottom and steeply rising emission on either side. The T4 sensor measures on the bottom of the valley, corresponding approximately to just above the tropopause. T1 sees only emission from the surface. T2 also sees the surface at high altitudes like the Tibetan Plateau, Antarctica and and the peak of the Andes. That is why there is no lower troposphere satellite temperature from those regions.

A good indication that the satellite orbital drift/decay corrections are valid has been demonstrated by the agreement between data using the old satellite #15 and the new Aqua AMSU which has station keeping jets and doesn’t require the drift correction. See the Jan 03 2008 readme at the UAH site.

While the rationale for all these adjustments sounds reasonable when first proposed in textual scientific form, when you look at what they “actually” did to the data (not that they explain what they actually did, it has to be post-adjustment audited), it makes no sense whatsoever unless you assume they are biased in adjusting the temperature records upwards to prove their pro-AGW bias.

At least it appears that the MSU data from RSS and UAH is not biased so we should just rely on it and throw the GISS, Hadley Centre and GHCN data OUT (or just go back to the raw temperature data instead.)

You’ve clearly done some thing other than just change the overall offset as the shape of the distributiions (number of entries in each bin has changed).

If you want to compare the 4 data sets should you not plot the distributions of the absolute values of the temperatures and then compare their means and spread?

As a minimum, any differences in the mean absolute temperature in the four data sets would informative.