The National Climate Assessment report denies that siting and adjustments to the national temperature record has anything to do with increasing temperature trends. Note the newest hockey stick below.
h/t to Steve Milloy
Source: http://nca2014.globalchange.gov/system/files_force/downloads/low/NCA3_Climate_Change_Impacts_in_the_United%20States_LowRes.pdf?download=1
Yet as this simple comparison between raw and adjusted USHCN data makes clear…
…adjustments to the temperature record are increasing – dramatically. The present is getting warmer, the past is getting cooler, and it has nothing to do with real temperature data – only adjustments to temperature data. The climate reality our government is living in is little more than a self-serving construct.
Our findings show that trend is indeed affected, not only by siting, but also by adjustments:
The conclusions from the graph above (from Watts et al 2012 draft) still hold true today, though the numbers have changed a bit since we took all the previous criticisms to heart and worked through them. It has been a long, detailed rework, but now that the NCA has made this statement, it’s go time. (Note to Mosher, Zeke, and Stokes – please make your most outrageous comments below so we can point to them later and note them with some satisfaction.).
Zeke Hausfather (May 7, 2014 at 11:55 am) “Thankfully most of the inhomogenities (including UHI) appear to show up more as a set of smaller step changes rather than a very gradual warming bias, though more would could be done analyzing this.”
Zeke, thanks for the information. It seems like the stepwise urbanization needs to be tested particularly when the step threshold is tuned for other discontinuities. Thanks for the link to the Williams paper. I just scanned it. I agree with their conclusion that increases in Tmax are probably underestimated with their method. But it seems likely to me that Tmin rises are overestimated. Those are the most significant effect of urbanization. Tmax rarely changes due to UHIE in my experience.
But… but UHI adjustments must be in the warmer direction! Look at it this way: the more people are at any place, the more energy is drawn from the surrounding environment because peoples body temperature is about 37°C and this is warmer than the air at most places. What do you think where the energy to heat those people up comes from? It has a cooling effect.
/sarc
There doesn’t seem to be anything terribly amiss with the (first three months of) 2014 HCN data when compared with the CRN data or the new Climate Division dataset.
http://www.ncdc.noaa.gov/temp-and-precip/national-temperature-index/time-series?datasets%5B%5D=uscrn&datasets%5B%5D=climdiv&datasets%5B%5D=cmbushcn¶meter=anom-tavg&time_scale=3mo&begyear=2005&endyear=2014&month=3
-Chip
my class 1s and 2s
then homogenization
silences their song
Nik, go jump in a lake! Steve asked questions, I pointed him in the direction of honest answers. He never replied back to this post, so he is either doing his homework as he should or he was a troll. The post is fairly easy to understand and the information he asked about is easy to get to. If you intend to post on a blog you should at least understand the subject. Or possibly think you understand it.
Sometimes parallels can be downright eerie.
eric1skeptic: [trimmed]
Will Nitschke, since Iron Man is often Steve’s most prolific commenter, I am exactly trying to DISCONNECT Goddard from being associated with him and by extension every skeptic too. If this issue isn’t blindingly obvious to you then it suggests a severe lack of both political savvy and emotional intelligence. It’s called constructive criticism. I say that as one of the most active online skeptics on news sites who also lives but four blocks from Hansen’s old office here on the Upper West Side. Goddard is just really bad at PR in what has become a PR war. Criticizing him isn’t some act of treason that reflects on my “credibity.”
David A: This is like that old episode of Saturday Night Live: “What’s the *PRICE* of the car?” but the sales guy won’t ever say it. I *know* where the archive of obscurely formatted data is, but its been months now that I’ve asked somebody, anybody with graphics software set up (like I did three years ago but no longer have) to finally just PLOT it, raw and adjusted. Each month more makes me quite suspicious if a classic Hide The Decline issue really exists, because nobody has shown the actual decline.
David Riser, what skeptics need to do isn’t offer homework and accusations but to offer quickly comprehendible infographics, which I happen to be expert at producing, but I don’t have graphing software that can parse obscure climate data files that rely on metadata for station identification. This is so terribly silly, that such an *extreme* claim of fraudulent data adjustment comes only from a single blogger’s software who refuses to show the two plots that created the difference curve! Am I dreaming or something? It’s quite surreal that Goddard’s plot is suddenly appearing here without comment, just as if it’s handed down from on high. Commenter Steve’s concern was spot on, that he couldn’t yet even show friends this claim for fear of ridicule. Goddard’s claim still exists in a bizarre sideshow vacuum, which is a shame.
@NikFromNYC – Love him or revile him, Steve Goddard is no “bizaare sideshow”. He is a pit bull that has found a target and will not let go – the temperature adjustments. As such, he has been cited numerous times on both blogs, and news sites for his insightful articles.
As long as you follow his rules of posting, he does not care about your private life. To tar him with a “guilt by association” is merely a diversionary tactic to those who either do not like him, or cannot debate him.
You are better than that.
@NikFromNYC
The Steve Goddard site is not interested in your opinions on how he should run his site. If you think of SkS and RealClimate as propaganda sites, think of Real Science as counter-propaganda. I’m not big on any form of propaganda, but other obviously feel it has its “uses.”
Goddard’s, according to my understanding, tolerates all comments as long as they are not overt trolling and not completely off topic. I presume he has that policy because the propaganda sites heavily censor negative commentary. Hence his desire to be “open”.
Goddard provided links to the data and explained how he calculated the graph. It seems to me that it would be far more interesting if you’d done an analysis rather than just concoct an accusation. I’m certainly open minded either way.
Well, give it a try you guys. Find someone you know who doesn’t have a strong position on any of these issues, and send them to Goddards site. What exactly will you tell them when they ask “Don’t you have any sources who aren’t nutcases and who don’t hide their identities? Can’t you send me to one of them instead?”
Zeke Hausfather (May 6, 2014 at 12:43 pm)
“This move leads to a big step change downward, which is removed via homogenization.”
Indeed. And it is very strange, especially if we assume:
Zeke Hausfather (May 7, 2014 at 8:43 am)
“UHI is real, but its impact isn’t huge.”
In fact, you do not know the magnitude of this impact because you can not assess the gradual increase in perturbations.
You could however use proxies, such as TLT :
Zeke Hausfather (May 7, 2014 at 8:56 am)
“If I recall correctly, the TLT amplification factor over land is actually right around 1.”
But with a better memory : http://img215.imageshack.us/img215/5149/plusuah.png
@Steven Mosher says: at May 6, 2014 at 1:58 pm:
“As always I will wait to examine the data as used
And code as run…”
Mr Mosher, you are to be congratulated on your rigorous approach to the science, and I’m heartened to see that you apply it universally.
I have no real standing here, and I was wondering if you could do the world of science a favor?
Could you please have a chat with Professor Michael Mann, Professor Stephan Lewandowsky, Dr Phil Jones, aah …
… I think I’ve got a list here somewhere …
… Can I get back to you?
@ur momisugly Matt G This indicates that cooling over recent years should show more with surface data than satellite data.This indicates that cooling over recent years should show more with surface data than satellite data.
Yes. It works both ways. Presence of heat sink will exaggerate both a warming and cooling trend. Since our 1979 – 2008 raw+MMTS data shows overall warming, the bias is towards warming. Same goes for 1998 – 2008, but reversed, with the cooling spuriously exaggerated.
Its worth pointing out that Anthony finds that the best sited stations have the same trend as the badly sited ones post-homogenization. They appear to have a lower trend prior to homogenization, though in Fall et al they had the same trend, so its worth looking in more detail exactly what changed in the ratings between the old and new papers.
I can answer that.
The old ratings are based on Leroy (1999) which measure only distance to heat sink. The new ratings are based on Leroy (2010), which account for both area and distance.
We noticed the problem with Leroy (1999) back when we were working on Fall et al. We had a running joke about how all Class 4 stations are equal, but some Class 4 stations are more equal than others.
evanmjones,
——
“@ur momisugly Matt G This indicates that cooling over recent years should show more with surface data than satellite data.This indicates that cooling over recent years should show more with surface data than satellite data.”
Yes. It works both ways. Presence of heat sink will exaggerate both a warming and cooling trend.
——
This is only true for high latitudes (above 60 °). Overall, the opposite is expected : tropospheric amplification due to change in absolute humidity.
This is only true for high latitudes (above 60 °). Overall, the opposite is expected : tropospheric amplification due to change in absolute humidity.
Oh, sorry for the confusion: I was only referring to heat sink effect, not LT/surface comparison. (I’ll let Dr. Chirsty address that; he’s the expert.)
I.e., if it cools, the badly sited surface net will exaggerate the cooling. If it warms, then warming will be exaggerated. Therefore, during the “pause”, trend will not be exaggerated in either direction.
evanmjones,
Thank you for the reply. I’m intrigued, what are these heat sinks that can act in both directions?
My understanding of the problem (based on an energy balance) is that the main anthropogenic influences are always going to warming (energy consumption and urban drainage).
@ur momisugly phi
Be sure not to confuse the actual reading and the trend. Theoretically, a station could have very high (spurious) readings, yet show no trend over time at all.
A heat sink is generally a structure or paved area. They store heat and release it at Tmin. The disparity between the sink and the sensor temp widens as warming continues. When cooling intrudes, the effects are reversed: there is disproportionately less heat stored by the sink as it cools, just as there was disproportionately more heat being stored on the way up.
Or, to look at it another way, when there is warming (natural or anthropogenic), the effect exaggerates the trend on the way up. On the way back down, there is less and less heat in the sink and the process reverses itself.
What goes up, must come down.
The sensor will be reading will too high in both cases. But the higher the temperatures, the more the greater the spuriously high offset. So it actually increases the trend.
That’s what NOAA missed. They figured if a station was offset 1C too high in 1979, it would be also be offset 1C too high in 2008. But during that warming period, the heat sink effect came into play and by 2008 it is reading over 1.5C too high. So the trend (sic) was exaggerated by 0.5C.
Then say it cools back down to 1979 levels: It will read just the same as it did in 1979. The same effect that created the extra warming has reversed itself to produce extra cooling. It is still reading 1C too high, of course. But it was reading 1.5C too high in 2008. So it cooled by an extra 0.5C on the way down just the same as it warmed 0.5C on the way up.
Waste heat (burn barrel, BBQ, AC exhaust) is an entirely different dynamic and may decrease trend (esp. at TMAX) as the effect swamps the sensor, even as the offset remains way too high.
evanmjones,
I think I got a good estimate of perturbations for a regional case thanks to the use of multiple proxies of high quality and consistent. I have not seen the phenomenon you describe on Tavg but a warming bias gradually increasing whether in an overall situation of warming or cooling.
In my opinion, the main effect of various pavements is not related to thermal inertia but to the lack of evaporation induced by the drainage. If you do the math, you will see that the additional energy available for sensible heat is about one third of the solar energy received. This is huge and more than enough (with energy consumption) to explain the bias. Which bias we can roughly estimate when a change of site occur.
NIk,
Info Graphics don’t help folks who ask questions which are plainly answered on the graphic and in the post if you bother to read it, demonstrate basic knowledge later in the post, and then say no one will read this without answering those questions. Hence I imply he may be a troll and give him homework if you will that answers the questions he already knows for someone who may actually care but have a hard time reading the post for some bizarre reason. Kind of like how you seem a bit trollish at times. Nothing personal but this post is pretty easy to understand and the hockey stick graph is pretty easy to figure out and duplicate, so maybe you didn’t actually read the whole thing in which case I would cut you a tiny bit of slack.
[snip this is wayyyyyyyyyyyy off topic. Stop posting this crap – Anthony]
@phi
On a regional basis, yes. All sorts of things can be going on there. I like the drainage construct. But you are using Leroy (1999). It’s insufficient for rating.
But that is a mesosite issue. I am looking at microsite, only. For my purposes, if 10% or less area within 30 m. is heat sink (etc.), it makes it a Class 2 and that’s as good as it gets. My “local USHCN site” in Central Park has very good siting (Frankie and Johnnie, paired Hygro and MMTS backup.). And — in the middle of Manhattan — it has quite a low trend.
Mesosite does matter. Trends in urban areas are a bit higher than the undeveloped. ’tis true. Cropland is even worse. “Rural” my patoot. It’s not even bucolic. But that is not what is making the GHCN trends a travesty.
Sorry UHI guys. But not to fear, I’m just going to draw you in a little closer. Microsite is where it’s at. The place to be.
Microsite is the new UHI. You heard it here first. Word up.
By the way, our study period is only from 1979 – 2008, a nice patch of US warming, coinciding with the satellite record and compatible with Menne (2009). And that means the metadata is quite tight, as far as these things go. COOP as a whole has sparse metadata, but USHCN meta is far, far better.
Anthony & Evan,
Best of luck in your submission and I hope you can get it published soon and in a journal you’re happy with!
Have you read our study of the Surfacestations results yet? Pdf here: http://oprj.net/articles/climate-science/11. Obviously we did not have access to your new Leroy, 2010 results, and so we were using the Fall et al., 2011 dataset. However, our results seem to roughly concur with your findings.
We found poor siting increased the unadjusted trends by about 32% and TOB-adjusted trends by about 18%. The nominal “good-poor” difference for the fully-adjusted trends is close to zero, but this seems to predominantly be a result of the blending problem with the Menne et al. homogenization algorithm.
We found two blending problems were occurring:
1. As Evan mentioned above, because the good stations are in the minority, the homogenization algorithm tends to adjust the good stations to better match the poor stations, i.e., more siting biases are introduced to the good stations than are removed from the poor stations.
2. Many rural USHCN stations are affected by urban blending in the fully-adjusted dataset. This introduces a general “warming” trend into the entire dataset, substantially increasing the average trends of the USHCN.
For anyone who doesn’t want to read our full paper (it’s quite long & detailed), we wrote a shorter summary of our main findings on our blog here
We have also uploaded all the data and code for our paper to FigShare: http://dx.doi.org/10.6084/m9.figshare.1004025
Anthony,
When do you think you will publish this?
Wow. I must be on a moderation list. Instant comment was most innocent question I’ve ever posted. IFAIK, I’ve never posted an immoderate comment anywhere.