UHI in the U.S.A.

Zeke Hausfather has contributed a guest post at RealClimate about his latest publication studying the impact of the “urban heat island” (UHI) effect on temperature trends, and how effective present correction methods are. The two-sentence summary:


The simple take-away is that while UHI and other urban-correlated biases are real (and can have a big effect), current methods of detecting and correcting localized breakpoints are generally effective in removing that bias. Blog claims that UHI explains any substantial fraction of the recent warming in the US are just not supported by the data.

Do take a look at the RC post, it has much more detail, and at the paper.

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33 responses to “UHI in the U.S.A.

  1. For AGU members or those with access to a library, you can get the final journal version (which, in my opinion, is much easier to read) here: http://onlinelibrary.wiley.com/doi/10.1029/2012JD018509/abstract

  2. I should also add that the guest post at RC is coauthored by Matt Menne (from NOAA’s NCDC), and that he, Claude Williams, Troy Masters, Ron Broberg, and David Jones all helped write the paper.

  3. I wonder what are the blogs that make the claim that the appearance of warming is entirely attributable to the Urban Heat Island effect.
    And why they are taken seriously.

    • Ask Mr Watts about his surface stations project..

      Ok, they couldn’t actually find a UHI effect no matter how hard they tried, but that was the implication of the whole surface stations thing.

    • Arthur,
      Never underestimate the power of an ideologue to delude himself…especially in the good ol’ US of A, the capital of stupid.

    • You need look no further than WUWT. Watt’s mission in life is to somehow prove that the U.S. temperature record is fundamentally flawed due to poor siting of stations in urban areas.

      Of course, he is completely wrong about that. Numerous other studies (including the latest paper by Zeke et. al.) show that the UHI adjustments in the various global temperature records are valid (consonant with rural stations in the same area) and necessary.

      Basically, the likes of Watts and his ilk start out with the answer that conforms with their ideology (there is no global warming, and if there is, we didn’t cause it. It’s all natural cycles), and then work backwards from there. The resulting twists and contortions they go through in trying to disprove reality are fun to observe… in a pathetic/funny kind of way.

      • Horatio Algeranon

        “Theory Wattsification”
        – by Horatio Algeranon

        Reality has been falsified
        This really can not be denied
        We’re confident
        100 percent
        Karl Popper must look down with pride

      • “Watt’s mission in life is to somehow prove that the U.S. temperature record is fundamentally flawed due to poor siting of stations in urban areas.”

        Note that it was RPSr that began flogging this horse, and Watts volunteered, apparently, to organize the “citzen anti-science” surface stations project. In a very real sense, Watts is RPSr’s protege.

    • From http://wattsupwiththat.com/2012/07/29/backstory-on-the-new-surfacestations-paper/:

      After Muller could not find strong signal that we knew must be there by physics of heat sinks…and neither could we in Fall et al 2011, we went looking, and discovered the new Leroy 2010 classification system and WMO ISO approval. We knew it would take a lot of work to get old metadatabase into shape. And so it began…

      Not examining the data to see what it says, but searching for anything to support for an answer they “knew” was true. Confirmation bias writ large…

  4. Why assume that belief is involved rather than dishonesty?

    I rewatched the 60s movie “The Train” the other day. In it Paul Scofield plays an art obsessed Nazi colonel who wants to spirit a whole museum of art back to Germany in the last days of WW2. The gag at the core is that the French curator mistakes the colonel for an art lover. What he’s been doing as he stares at the work is simply lusting over the amount of money he could make selling it.

    Why assume that denialists simply aren’t crude clowns who don’t want to give up their gas guzzlers or their jobs in the extraction industry? Isn’t the “tell” about their sincerity the willingness to cite often re-bunked arguments?

    • “Why assume that belief is involved rather than dishonesty?”

      In Watts’s case, I think you can get your cake and eat it to …

      1. The *belief* involved is his right-wing political ideology, and his opposition to the political consequences that necessarily follow if the seriousness of climate change is accepted across the political spectrum.

      2. He’s willing to be dishonest in order to support his political ideology …

  5. Also check out caerbaanog’s comment on that RC post, in which he/she describes updates to his/her tool for computing trends on any stations you’d like.

  6. To give folks an appreciation of how utterly pathetic the “Warming is due to UHI” drum that Watts has been beating on all these years, check out this little image: http://imageshack.us/photo/my-images/59/rural36x36.jpg

    It shows what I got when computed global-average temps from 32 rural stations scattered around the world. Results for both raw and adjusted GHCN V3 data are shown (the official NASA/GISS land temperature aka “meteorological stations” results are shown for comparison purposes).

    Summary of the data-crunching procedure:
    1) Divide up the Earth’s surface into 32 grid-cells of approximately equal size.
    2) Search each grid-cell for the rural station with the longest temperature record.
    3) Compute the temperature monthly-average temperature anomalies for all stations and average them all together for each year.

    That’s it — the “one station per grid cell” procedure means that you don’t even have to bother with area-weighting. Just simple dumb averaging is all you have to do.

    Performing an “in the ballpark” sanity-check on the GHCN temperature data that shows that UHI contamination isn’t a significant factor in the published global-average temperature results just isn’t that hard.

    Folks who want to play around with the temperature data in a pointy-clicky sort of way might want to download my global-temperature virtual-machine (VM) file from: http://tinyurl.com/NASA-HANSEN

    It’s a big download (about 1GB), but if you follow the simple instructions (link on the right-side of the download panel), you will be able to use the VM file to launch a “plug and play” virtual machine that will let you “roll your own” global-average temperature estimates by clicking on stations on a Google Map display. All data and software are bundled together and ready to go.

    The global-temperature averaging procedure that I implemented is a very dumbed-down version of the NOAA gridding/averaging algorithm — so the package should be considered to be more of a toy than a serious analysis tool.

    But it does a nice job of demonstrating how robust the NASA global temperature results are — surprisingly few stations are needed to produce a global-warming trend consistent with the NASA results. This is something that might be worth turning science students loose with.

  7. I guess I should have read through the comments here before posting mine. Tom Dayton already put up a post about that global-temperature tool.

    (So let me get this straight — drink coffee first, and *then* post)

  8. I had a comment for the ridge regression thread, but I guess it’s closed now, right? If you drop me an email, I’ll email it to you anyway, if you are interested.

  9. Horatio Algeranon

    Denywarmman

    – Horatio Algeranon’s rendition of “The Highwayman” (by Alfred Noyes)

    The blog was a torrent of stupid among the gutsy deniers,
    The host was a whiny weatherman denying on webby wires,
    The thread was a ribbon of Soonlight clouded by Cosmic Rays,
    And Denywarmman came denying—
    denying—denying—
    Denywarmman came denying, up on the blog home-page.

    II

    He’d a half-cocked-claim in his post-head, a bunch of ice on his graph,
    A trend showing global cooling, and pieces of broken hockey-staff;
    He fitted with many a wrinkle: his sigmas were up to the sky!
    He denied with a fossil-fueled twinkle,
    His fruits and nuts a-twinkle,
    His cherry pick a-twinkle, under the fossil-fueled lie.

    III

    Over the stats he clattered and clashed in the dark stat-yard,
    And he tapped school-math on the shutters, but all was locked and barred;
    He whistled a tune to the Window, and who should be waiting there
    But the Brenchley-Lord’s blog-eyed doter,
    Judith, the Brench-Lord’s doter,
    Painting a dark red Pause-line onto a rising stair.

    IV

    And dark in the dark old stat-yard a confidence-interval creaked
    Where Tamino the blogger listened; his curiosity piqued;
    His eyes were hollows of mathness, his hair like Thomas Bayes,
    But he loved the Brench-Lord’s fodder,
    The Brench-Lord’s flat-line fodder,
    Mum from his blog he listened, and he heard Denywarmman say—

    V

    “One post, my Uncertainty-slayer, I’m after a prize to-night,
    But I shall be back with the Station photo before the morning light;
    Yet, if they press me sharply, and harry me through the day,
    Then look for me by Soonlight,
    Watch for me by Soonlight,
    I’ll come to thee by Soonlight, though NOAA should bar the way.”

    VI

    He rose upright in his armchair; he scarce could reach Ayn Rand!,
    But he fetched Steve Galtard from the basement! His post burnt like a brand
    As the Cosmic Rays of Svensmark came beaming over his breast;
    And he blessed its rays in the Soonlight,
    (Oh, sweet, Cosmic Rays in the Soonlight!)
    Then he tugged at his mouse in the Soonlight, and galumphed away to the BEST.

    PART TWO

    I

    He did not post in the dawning; he did not post at noon;
    And out o’ the tawny sunset, before the rise o’ the Soon,
    When the thread was a Moebius ribbon clouded by Cosmic Rays,
    A scientist troop came sciencing—
    sciencing—sciencing—
    Jim Hansen’s men came sciencing, up to the blog home page.

    II

    They said no word to the Brench-Lord, they read his e-mail instead,
    And they gagged on his fodder and ground it — with a foot — and his flat-line dead;
    All of them knew what the case ment, with statistics on their side!
    There was warming at every window;
    And hell at one hot window;
    For scientists could feel, through the window, the warming he had denied.

    III

    She had tried to get their attention, with many a jousting jest;
    With Italian flag beside her, and a Muller beneath The BEST!
    But they kept good watch and they dissed her.
    She heard Denywarmman say—
    “Look for me by Soonlight;
    Watch for me by Soonlight;
    I’ll come to thee by Soonlight, though NOAA should bar the way!”

    IV

    She twisted her claims behind her; but all the Not!s held good!
    She waved her hands at her figures, she said were “Misunderstood!”
    She stretched and strained credibility, and the hours crawled by like years,
    Till, now, on the stroke of midnight,
    Warm, on the stroke of midnight,
    The tip of her mouse-finger touched it! The flag at least was hers!

    V

    The tip of her mouse-finger touched it; she strove no more for the BEST!
    Up, she stood up to attention, with a Burn-barrel beneath her post,
    She would not risk their mocking; she would not strive again;
    For the thread lay bare in the Soonlight;
    Blank and bare in the Soonlight;
    And the warming that remained in the Soonlight wilted the Russian grain.

    VI

    Click-click; Click-click! Had they heard it? The mouse-clicks ringing clear;
    Click-click, click-click, in the distance? Were they deaf that they did not hear?
    Down the ribbon of Soonlight, over the Bishop’s Hill,
    Denywarmman came denying,
    denying, denying!
    The scientists looked to their warming! She stood up, straight and still!

    VII

    Click-click, in the facty science! Click-click, in the echoing right!
    Nearer he came and nearer! Her face was like a light!
    Her eyes grew wide for a moment; she drew one last ice graph,
    Then her mouse-finger moved in the Soonlight,
    Her confidence shattered in the Soonlight,
    Shattered by BEST in the Soonlight and warned him—with the chaff.

    VIII

    He burned; he spurned the BEST; he did not know who stood
    Bowed, with her head o’er the keyboard, drenched with her own spilt food!
    Not till the dawn he heard it, his face grew grey to hear
    How Judith, the Brench-Lord’s doter,
    The Brench-Lord’s blog-eyed doter,
    Had watched for Denywarm in the Soonlight, and paused in the warmness there.

    IX

    Back, he spurned like a madman, shrieking a curse to the sky,
    With the open thread smoking behind him and his mouse-finger brandished high!
    Un-read were his spurns i’ the golden Soon; un-read was his latest post,
    When they shot his claim down on Denyway,
    Down at his blog on Denyway,
    And he lay in the mud on Denyway, with a bunch of links to burnt toast.

    X

    And still of a winter’s night, they say. when the blog is of deniers,
    When the host is a whiny weatherman denying on webby wires,
    When the thread is a ribbon of Soonlight clouded by Cosmic Rays,
    Denywarmman comes denying—
    denying—denying—
    Denywarmman comes denying, up on the blog home-page.

    XI
    Over the stats he clatters and clashes in the dark stat-yard,
    And he taps school-math on the shutters, but all is locked and barred;
    He whistles a tune to the Window, and who should be waiting there
    But the Brench-Lord’s blog-eyed doter,
    Judith, the Brench-Lord’s doter,
    Painting a dark red Pause-line onto a rising stair.

    • Ah, nostalgia and amusement both! You can come riding to the old blog-page anytime, as far as I’m concerned!

    • Geez Horatio, that’s approaching American Pie-ness :-)

    • If Watts didn’t exist we’d be denied [cough] your art, Horatio…

      • Horatio Algeranon

        The cast of characters is strong and deep
        But I have mockery to heap
        And denials to mow before I sleep
        And denials to mow before I sleep
        — from “Stopping by Blogs on a Poey Evening”

      • Horatio Algeranon

        here’s the rest

        “Stopping by Blogs on a Poey Evening”
        – by Horatio Algeranon — with a little help from the Frost kings (Robert and Anthony)

        Whose blogs these are, I think I know
        His host is in denial though
        He will not see me lurking here
        To watch his blog fill up with Poe

        My little mouse must think it queer
        To stop without a comment near
        About “Ice gain” on frozen lake
        The dumbest posting of the year

        He gives his mousey finger a shake
        To ask if there is some mistake
        The only other sounds the weap
        Of Wattsy whine and clowny fake

        The blogs are gobbledy gook — and deep!
        But I have mockery to heap
        And denials to mow before I sleep
        And denials to mow before I sleep

      • Horatio, you are the poet laureate of SIWOTI.

      • Horatio Algeranon

        “Somewatts Is Wrong On The Internet”
        – by Horatio Algeranon

        Somewatts is wrong on the internet
        Not “somewhat wrong”
        But “somewatts wrong”
        About as wrong as one can get

  10. Superb, Horatio. Pun density is impressive! :-)

  11. Australians

    complete list. Australian politicians, stance on climate change

    please spread around

    https://uknowispeaksense.wordpress.com/election-2013/

  12. infrared filter for astronomers, because the night sky is so bright in the infrared: A complex multi-notch astronomical filter to suppress the bright infrared sky

  13. Since there isn’t an open thread for a few pages back, I’ll post this off topic query here. I’ve been looking at a dataset that looks to be bimodal. Of course, I have very limited statistics, and most of the data are either upper limits (part failed below stress x) or lower limits (parts in “upper mode” didn’t fail). Taking the worst-case distribution consistent with the data (lower mode at the upper limits and upper mode at the lower limits), Pearson’s bimodality coefficient is still ~.5, close to significant, and the order statistics look more like bimodality than they do a thick-tailed distribution. Anyone have any suggestions for other tests I could apply?

  14. The Weathermen

    A tribute to misguided TV weathermen everywhere — by MetzO’Magic
    (with inspiration drawn from, and apologies in advance to, Horatio)

    The weathermen – they’re birds of a feather,
    The weathermen – they’re all in it together,
    The weathermen – can’t predict the weather, even when it’s yesterday’s

    (probably best when recited in rap style, even though I’m certainly no fan of the genre)