The Geography of USCRN Average Air Temperature Trends during the 2004-2014 Decade over the Contiguous United States

Guest essay by Samuel I Outcalt

The USCRN monthly average air temperature records were searched for continuous records covering the 2004 to 2014 decade over the contiguous United States. The average values were selected as these averages represented the average of several sensors. The records represent mid-month averages so a simple interpolation algorithm was used to convert the x-axis of plots from continuous months with an initial index value of zero to fractional years [ x = 2004+(1/24) + (x/12) ]. As mid month data was used, the record stream ran from 1 January 2004 to 1 January 2015. The graph for Elgin, Arizona is displayed as Figure 1.

Figure 1. The record for Elgin, Arizona.

It was later discovered that Elgin was the only record that could NOT be easily included in within an area of stations having a negative trend during the decade.

The map of the station location slopes in temperature change during the decade is presented as Figure 2.


Figure 2. A map of the average temperature (C) change during the decade. In some cases the station labels were shifted slightly to avoid state border lines and label overlap.

It is apparent that the region between the Appalachian and Rocky Mountains is cooling compared to warning regions along the northern sections of both the Atlantic and Pacific Coasts. It should be noted that in some states with paired station records there is a significant difference in the magnitude of the decade trend. These differences indicate significant site effects especially in the flat agricultural regions in along the Gulf and Atlantic Coastal Regions. Some of these variations may have been introduced by downwind crop rotation and increased aerodynamic roughness produced by the rather massive structures use to shield precipitation gauges.

The absolute magnitude of larger decade trends extrapolated to degrees [ C ] / Century far exceeds the magnitude of the approximate 3 to 5 C global warming since 1870. The warming of 3 C / Century was first documented from an analysis of the geothermal profile at Barrow, Alaska. That analysis, which was completed and reported by the Alaskan Branch of the USGS in 1970. The well documented post 1870 warming is considered by some to mark the end of the Little Ice Age and others to be an artifact of the onset of the industrial revolution. If the present decade trends were to extend for a century, the 2104 air temperature contrast between Arco, Idaho and Wolf Point, Montana would be near 20 C.

A precision spatial interpolation of the data due to the lack of records in many areas. Even with a dense network the geographic interpolation algorithm would have to be conditioned by topography. In order to drive home the pattern of the decade trend contrasts a hand drawn border was used to draft Figure 3.


Figure 3. The area with cooling temperatures is shaded light blue.

In Figure 3 the location of Elgin. AZ is indicated (*) but not labeled. The the trend sign boundary would have become too irregular to include it in the cooling area. However, the contrast between it’s value of -0.25 and the nearby value of +0.16 indicate that the trend values in complex terrain are not only conditioned by local site effects by the local topography.

This brief analysis indicates that the areas of warming and cooling display a strong degree of spatial correlation.

However, there are strong indications that the expansive addition of more USCRN stations will produce more complex contrasts by the end of the next decade.

The pronounced mid continent cooling appears to be the product of the increased frequency and/or lowered temperatures of winter Arctic Air invasions. The pronounced warming New England and the Pacific Coast, which extends over most of the Southwest may be traceable of ocean circulation changes.

This short exploration indicates that simple linear regression applied to all the variables supplied by the USCRN data will provide a robust image of the Geography of Modern Climate Change, when applied to the present data over shorter time spans. The calculation requirements are massive when the large number of stations added during this decade is considered. However, this task as well as the design of topography conditioned extrapolation algorithms is well within the capacity of the computers at the National Center for Atmospheric Research, now with massive computers at both Boulder and Cheyenne.


90 thoughts on “The Geography of USCRN Average Air Temperature Trends during the 2004-2014 Decade over the Contiguous United States

  1. Since the PDO & AMO are, or were, in their warm phase warmer coastal regions are to be expected, not climate change just a phase change of natural oceanic cycles.

  2. In absolute newspeak, this known problem with climate is called “the warming hole”, and it is theorized to be due to irrigation and changes to cloud/precipitation patterns, due to human use of water for irrigation.

    I swear I did not make any of that up. Except for calling it an example of newspeak. It should be called the cooling hole. It shows up clearly using any temperature data, not just recent high quality data.

  3. I am not sure what you are getting at in the text of the article. Trying to find a statistically significant trend in only 10 years of temperature data is tricky.

    • It depends on what one is attempting to demonstrate. You need a longer period (with an eye on negative vs. positive PDO, etc., to judge medium-term warming.

      But sometimes less is okay: we use an 11-year period, 1998 – 2008, to demonstrate what happens during a (US) cooling period. The amount of cooling offsets the shortness of the series. We could have gone to the present, but that would attenuate the change, and we wanted a cooling interval not a near-flat trend. That short series is excellent to judge that — but if one tried to impute global (or US) cooling based on that interval, it would be a horrendous cherrypick.

      • Here’s a short trend for you that displays climatalogical fact: Tempurature decreases from Summer into Winter. That a short enough period for you?
        Even Better, its cools down going from the afternoon into nightime! its repeatable, and rarely happens any other way! never mind that it warms up again the next day, thats the future, nothing to worry about.

        As you point out, you picked the period to demonstrate your point, you ignored other data because it would have lessened the impact of what you are trying to demonstrate. Idiocy

  4. I hope you are using unadjusted GHCN data, since the adjusted file excludes 2014 data from various stations, as well as instances where blocks of years were deleted from the last decade.

    My study of US CRN1 stations, top-rated for their siting quality, shows that GHCN adjusted data produces warming trends several times larger than unadjusted data.

    The analysis shows the effect of GHCN adjustments on each of the 23 stations in the sample. The average station was warmed by +0.58 C/Century, from +.18 to +.76, comparing adjusted to unadjusted records.

    19 station records were warmed, 6 of them by more than +1 C/century. 4 stations were cooled, most of the total cooling coming at one station, Tallahassee.

    So for this set of stations, the chance of adjustments producing warming is 19/23 or 83%.

    Details here:

    • He says clearly in the post that they are using USCRN (US Climate Reference Network) not GHCN (Global Historical Climatology Network). Different Data sets

      • Ric, I’m aware of those posts. I’m wondering why a site like Corvallis would use inferior siting or technology to report to HCN and a better setup to report different numbers to CRN.

      • Here’s some further info on CRN dataset.

        Daily data are calculated using the station’s local day.
        E. There are no quality flags for these derived quantities. When the
        raw data are flagged as erroneous, these derived values are not
        calculated, and are instead reported as missing. Therefore, these
        fields may be assumed to always be good (unflagged) data, except
        when they are reported as missing.
        F. The daily values reported in this dataset are calculated using
        multiple independent measurements for temperature and precipitation.
        USCRN/USRCRN stations have multiple co-located temperature sensors
        that make 10-second independent measurements which are used to
        produce max/min/avg temperature values at 5-minute intervals. The
        precipitation gauge is equipped with multiple load cell sensors to
        provide independent measurements of depth change at 5-minute
        I compared the Tmean for Corvallis to HCN Tavg, which are both calculated the same way: (Tmin+Tmax)/2.

        I still puzzle over the differences in the records; maybe different sensors are being used.

      • Why do you laugh? The well known and famous “Mann-made” Global Warming was and is obviously politically supported by liberal thinking people. So the verdict is perfectly true… ;-)

    • And I thought it was the ending of National League dominance of the All Star game what caused it.

      • No No No , it is the Tiger Woods factor, a lot fewer people are watching golf now and tv’ set are turned of temperaments are cooling and there is less use of golf courses. So fewer people are using golf carts that spew electrical wasted energy into the atmosphere
        There you go global cooling.

    • Correlation: Urban areas experience the urban heat island effect and are generally liberal?

  5. One can go back all the way to 1998 to detect a cooling taking place in United States

    The trend of United States annual and seasonal temperature anomalies has been declining for 18 years or since 1998. The only exception is the summer and more particularly, the month of June


    ANNUAL (-0.48 F/DECADE)

    These temperature anomaly trend declines are similar to past temperature declines in United States during 1895-1920 and again 1953 -1979. A similar cool period seems to have started during the current decade.
    Just look how the individual monthly temperatures are declining in United States since 1998, namely 9 months of the year show cooling, three show warming.. Spring , Winter and Fall are cooling and only the Summer is still warming due to one month only, namely June.


    The following are monthly temperature anomaly trends per decade for Contiguous US or 48 states as calculated by the NCDC/NOAA Climate at a Glance web page for the last 18 years [1998-2014]. The figures reflect the linear trend in Fahrenheit degrees per decade per NCDC/NOAA web page data using base period of 1998-2015. Blue colors show cooling, red colors show warming.

    DEC -0.41F/decade (declining)
    JAN -1.23 F decade (declining)
    FEB -2.73 F/decade (declining)

    SPRING (-0.06 F/DECADE) – DECLINING flat
    MAR +0.57 F/ decade (rising) but dropped 10 degrees F since 2012 alone
    APR -0.28 F /decade (declining)
    MAY -0.47 F/decade (declining)

    JUN +1.02 F/decade (rising)
    JUL -0.10 F /decade (declining)
    AUG -0.24 F/decade (declining)

    SEPT +.08 F/decade (declining) flat
    OCT -0.03 F/decade (declining) flat
    NOV -1.53 F/decade (declining)

    • Whoops, Herkimer. I didn’t see your post when I showed a graph showing declining Winter temperatures for the U.S. Yours is even worse than mine, though that might have been helped by the fact yours stopped at 1998 which had unusually warm temperatures.
      Still that 2.73 F drop per decade for February is astonishing. That’s a 27 degree Fahrenheit drop for February over a hundred years.

      Bob Clark

      • Hey you guys are so good at cherry picking i want to hire you when the season gets going! Will you all wait for me outside of home depot?
        I swear i’ll come for you, as long as the drought doesn’t kill all the trees (then there will be no cherries to pick)

      • Bob Clark
        It would be wrong to take a decadal February winter trend of -2.73 F based on an 18 year trend only and then say that this translates to 27F per century assuming that the trend will continue for the next 100 year . That is very remote. However we could use it to speculate a few decades ahead and that during the next 2-3 decades of continued cooling ( typical cooling pause last at least 20- 30 years) that February temperatures could drop by 2x 2.73 = 5.46 F to 3×2.73 = 8.i9 F more. If we check the last US cooling period 1945 to 1980, February anomalies did drop about 12 F from peak 1954 to low of 1979. Now the alarmists will say this will not happen due to global warming , but in fact, they apparently are not aware that it has already started since 1998 or they would not be making these silly warming projections for US . Sure, we will have some warm years in between when El NINO conditions prevail , but the decadal trend could show a continued February decline for the next 2-3 decades in my opinion

  6. Label your two regions in the graphic A and B. Their average temperature is (A+B)/2. Their IR radiation is A^4+B^4 (in arbitrary units).

    Now, according to GHG theory, the average temperature should remain the same if IR radiation remains the same.

    Start with A=10, B=10. average = 10, IR = 20,000

    Now change A and B. Increase A=11, decrease B=8.556.

    new average = 9.778, new IR = 20,000.

    We are told over and over again that GHG causes Climate Change, but as we can see regional changes in temperature change the climate, without the slightest change in GHG!

    • what this shows is that climate change is indeed man made. it stems from using a linear average to measure climate, when IR energy is a 4th power effect. As the earth moves heat between the Northern and Southern hemisphere to balance incoming and outgoing radiation between the hemispheres, this give rise to the polar see-saw. This changes regional temperatures, which affects the calculation of average temperature and climate, even when energy remains constant.

  7. 1) actual temperatures not anomalies. 2) displayed to wx.yz which is probably below the resolution of the instruments and is a statistical artifact not a real measurement. Certainly violates the rule for significant figures.

    • Satellites have smooth coverage, but they don’t do lookdown; they must view across to get the sweep. That makes them poor for polar coverage. They are also an MW proxy, and those readings can be spuriously affected by clouds and ice. It is also LT, not surface, so both warming and cooling is accentuated (Dr. Christy’s “upper bound” hypothesis).

  8. This is interesting, the coastal states primarily populated by left leaning warmists are warming and the fly-over states primarily populated by right leaning skeptics are cooling. Perhaps this partially explains the different perceptions of each group.

    • If only it was true. It would be interesting to add an in additional overlay representing urban sprawl and population growth figures for the same period.

      • In terms of macrosite and mesosite, the affects are not great. But the exurbanization (paved roads, driveways, etc.) has had a serious effect on microsite over the last century, and that has never been accounted for. And Microsite is the New UHI.

  9. Regional trend of US Annual temperatures since 1998 shows that except for the WEST , all regions have declining temperature anomaly trends

    8 out of 9 climate regions show a cooling trend .

    • OHIO VALLEY -0.9 F
    • UPPER MIDWEST -1.5 F
    • NORTH EAST -0.1F
    • NORTHWEST -0.1 F
    • SOUTH -0.5 F
    • SOUTHEAST -0.4 F
    • SOUTHWEST -0.1 F
    • WEST +0.7 F

    All climate data above is from NOAA Climate at a Glance web page and includes 2014 annual figures .

    This trend is similar to Canada . North America has cooing trend since 1998, .

    • 1998 is a high point, though. I prefer to run these things back to either 2001 or 1997. Nearly anything between 1998 (high) and 1999-2000 (low) turns out to be a cherrypick when one gives it the hairy eyeball. (I love it when sks grafts a smoothed series to the current record in 2000 — pimp my trend, friend!)

    • What would be the Winter declining trends for these regions? I would imagine they would be pretty bad particularly for the East and Midwest.

      Bob Clark

      • US CLIMATE REGIONS MONTH OF FEBRUARY temperature anomaly changes since 1998 OR 18 WINTERS per NOAA CLIMATE AT A GLANCE

        7 out of 9 regions show a dramatic rate of decline except WEST and NORTHWEST
        • OHIO VALLEY -6.1 F/ DECADE
        • UPPER MIDWEST -7.5 F/ DECADE
        • NORTH EAST -4.4 F/ DECADE
        • NORTHWEST + 0.8 F/ DECADE
        • SOUTH -3 F/ DECADE
        • SOUTHEAST -.2.3 F /DECADE
        • SOUTHWEST -0.3 F/ DECADE
        • WEST + 2.1/ DECADE

  10. That is a very interesting map. Are there any other maps like this for any other regions in the world like Europe, Australia or South America? It would also be interesting to see maps of the US from earlier, different decade long time spans.

    • This only for February 2015 , but it does illustrate what is happening in North America in comparison to the rest of the globe . This from Roy Spencer’s GLOBAL TEMPERATURE REPORT FEBRUARY 2015 . Notice the similarity to the graph at the beginning of the above article .

  11. “However, there are strong indications that the expansive addition of more USCRN stations will produce more complex contrasts by the end of the next decade.”
    -I’m not really sure what you mean by this. It sounds like you’re saying the trends you observed are an artifact of there being relatively few stations.

    “The pronounced mid continent cooling appears to be the product of the increased frequency and/or lowered temperatures of winter Arctic Air invasions.”
    -Could you expand on this? There’s no doubting that the past couple of winters have seen some pretty dramatic “arctic air invasions”. But also that was preceded by a winter in which a blocking high gave ridiculously high temps throughout “cooling” region. I’m wondering if the cooling trend might be simply due to the inclusion of two sequential cold winters that occur at the end of the period analyzed. Is there really a consistent trend of increased arctic air invasions?

    “This short exploration indicates that simple linear regression applied to all the variables supplied by the USCRN data will provide a robust image of the Geography of Modern Climate Change, when applied to the present data over shorter time spans.”
    -I’m not sure that it does. It definitely shows that short-term trends generally correlate between geographically similar stations, but does that make the trends “robust”? Or does it simply mean that the stations near each other exhibit the same trend biases as they experience the same anomalous winters at the end of the period?

  12. When you look specifically at the Winter temperatures the cooling trend is even worse for the U.S., at -1.13 degrees F per decade:

    This is more than a -10 degree F drop over a century, about -5 degrees C. The IPCC says there would be dire consequences of a 2 degree C increase in temperatures over a century, but nobody is considering this possible 5 degree C drop in Winter temperatures for the U.S.
    I got to believe this is comparable to the drop in Winter temperatures for the Little Ice Age.

    Bob Clark

    • There is no doubt that winters have been getting colder more in North America than other parts of Northern Hemisphere. There is some evidence that the trend of NORTHERN HEMISPHERE LAND ONLY WINTER TEMPERATUREANOMALIES have actually been declining since 1995 or 20 years at (–0.18C/decade) . Since 1998 the NORTHERN HEMISPHERE WINTER LAND ONLY TEMPERATURE ANOMALIES have declined more rapidly at (- 0.35C /decade.) Good example of this is in Eastern Canada

      Globally, the trend of GLOBAL WINTER LAND ONLY TEMPERATURE ANOMALIES declined at (-0.22C/decade.)

      I don’t think this is any start to an ice age but just part of a typical 30 year warm cycle followed by a 30 year cool cycle . If one looks back to the start of the last cool cycle after say1945 , North America started to cool first followed by Europe and Asia .

    • It’s worse than we thought!

      An 11.3 degrees F drop is 6.3 degrees C.

      Shivers me timbers!

  13. The 960 year solar activity cycle peaked in about 1991. The corresponding climate temperature peak lags the driver peak by about 12 years and the earth entered the beginning of the cooling trend in about 2003.
    Outcalt.s the current Guest Post show the typical pattern which develops in NA during a cooling trend i.e. more frequent Arctic air invasions.

    For the 960 year +/- periodicity. See Figs 5 -9 at
    Fig 9 shows clearly that earth is just approaching, just at or just past the peak in the latest millennial cycle.
    Fig14 shows that the solar driver peak occurred in about 1991 .
    The sharp drop in the Ap index from 2005 -6 seen in Fig 14 should produce significantly sharper cooling in 2017- 18
    The simplest working hypothesis is that the general trends from 1000 – 2000 will more or less repeat from 2000- 3000.
    Any forecasts from models which ignore this 960 year periodicity are entirely worthless and provide no useful basis for climate discussion.

    • This seems absolutely arbitrary. there is no hard proof that the so called 960 year cycle is over, it could be just a natural variation within the cycle and the maximum is still to come. thats if this is even a valid theory.

      Article itself is poorly written, in need of editing (words are missing…) and simply cherrypicking data. Conveniently he left of the data point that didn’t fit his drawing, because drawing a little squigglier line is a lot hard than drawing a “look i almost made it straight! be proud of me!” line.

      To the guy above who posted the graph of a crazy downward trend in winter tempuratures: one of the key tenants of climate change is that the extremes (i.e. hot and cold, wet and dry) become more extreme. your cherrypicking a measurement that is sure to demonstrate your point. And if the NOAA really released that graph, link to it. otherwise, it has been edited and misappropriated.

      • So absolutely everything including cooling is caused by global warming….

        You discount the very paradoxical presentation of the earths cycles without missing an alarmist beat.

        If the world is cooling a wide swing will happen towards the equator as we see today in an effort to bring the mid latitude areas down in temp. The result is an increased of negative temperature readings as we see today and continued wild swings to precipitate cooling further.

        In a warming world we would again see wide sweeps initially but as the temps rose mid latitudes the polar regions would be tightly contained. The mid latitudes would see and increase of temperature. This is not currently the case.

        The mid latitudes are the key… As this was shown earlier in a post above:

        “US CLIMATE REGIONS MONTH OF FEBRUARY temperature anomaly changes since 1998 OR 18 WINTERS per NOAA CLIMATE AT A GLANCE

        7 out of 9 regions show a dramatic rate of decline except WEST and NORTHWEST
        • OHIO VALLEY -6.1 F/ DECADE
        • UPPER MIDWEST -7.5 F/ DECADE
        • NORTH EAST -4.4 F/ DECADE
        • NORTHWEST + 0.8 F/ DECADE
        • SOUTH -3 F/ DECADE
        • SOUTHEAST -.2.3 F /DECADE
        • SOUTHWEST -0.3 F/ DECADE
        • WEST + 2.1/ DECADE

        The mid latitudes are indeed cooling and have been for a long time. Since 2002 the trend has been negative and the large swings of the polar jet continue.

      • “To the guy above who posted the graph of a crazy downward trend in winter tempuratures”: If you want to be viewed seriously, always quote what you are responding to. The graph is from NOAA, anyone who knows NOAA software and data will recognize it right away.

        “And if the NOAA really released that graph, link to it. otherwise, it has been edited and misappropriated.” Linking to sources is always good form, and certainly in this case that is still true. If you are talking about this image

        It is from the CAG page, found here

        If you generate your own, and try to link to it, you will find the trend line will not link correctly.

  14. Bob Clark
    I agree with you that the winters are taking a beating in United Sates . You mentioned the national winter cooling trend of -1.13 F/decade since 1995. The trend since 1998 is about -1.44 F/decade. But locally it is even worse since 1998 . UPPER MID WEST trend is 4.0/F /decade, OHIO VALLEY is -2. 7F/decade and NORTHERN ROCKIES AND PLAINS is -2.4 F /decade . Every climate region shows a decline except the WEST and NORTHWEST.

    • Have you seen the weather patterns that are causing the Hot/Cold dipole pattern over the US? Im sure if you only look at the last 3 years, you will get some impressive “decadal cooling” values.
      The bigger problem is the weather pattern that is causing the hot west/cold east. it is highly anomalous, has been contibuting to the greater drought in the southwest region, and certainly as extreme as the cooling in the east.

    • exactly how much have the sea levels dropped in your proposed ice age solution? I am impressed you know where, and to what extent (and even the names!) the ice age will cover.

  15. and to whomever these posts have to be “moderated” through, don’t be a bitch: post my comments and let the “scientific community of WUWT” answer for themselves.

  16. Judith Curry just looked at Australian temperature records on the interior. There was no change. The changes were on the coast. Somewhat similar?

    The CH4 levels have not changed since 2000 +/-, while the global temperatures have been flat but CO2 levels have risen.

    My suspicion is that the oceans have warmed historically, driving CH4 production and the global average. The global rise is thus (largely) a Computational Truth rather than Representational Truth: the math gives a global appearance of cause that does not reflect the actual, regional (distribution of) cause.

  17. “There is no doubt that winters have been getting colder more in North America than other parts of Northern Hemisphere.”

    GISS data shows the cooling trend clearly for winters.

    Siberia is cooling more than North America, and has been cooling longer.

    • Thanks for that link, sfx2020:

      It shows a pronounced cooling trend for Winter from 1988 to 2015 for the East region of North America and also for much of Europe and Asia. For some areas the drop is 4 degrees C, about 8 degrees F. Over a hundreds years, if the trend continued, it would be a drop of 30 degrees F in those regions(!)

      Bob Clark

      • Living here in Texas, I can tell that winters down here have gotten colder over the last 27 years, but it has been especially colder and more wintry down here in the last five. A couple of our biggest snowstorms here happened in late January/February 2011 and just a couple of weeks ago in early March (snow, ice, AND sleet!). So there is something to colder winters in North America, although I have not specifically checked the official weather records.

  18. If you think of the equatorial oceans as a boiling kettle, all of that hot water goes elsewhere, ie it tracks poleward where it warms the surface, and drizzles it’s way into cooler/drier air where it finally finishes falling as snow or rain.
    So then land surface temps respond to the oceans warm spots, and as they move land temps change. Both of those warm zones look to me to be the main tracks of ocean air masses as they cross the US.

  19. Cohen theorizes a strong negative feedback from early and heavy snow is causing a climate change. Certainly if NH winters are cold enough to bring the global mean to a negative state, something is changing.

    I checked, and just as multiple papers have stated, it is mostly Jan-Feb that is causing the colder winters.

    Ain’t that something?

  20. Good to see USCRN data starting to be examined. As already stated, the amount of data are not adequate to show any statistical significance. The first stations only started coming on-line in 2002. There were over 100 stations on-line in 2008, with more being added every year.
    The data from the USCRN should never require any adjustments of any kind.

    • When you also take into account the period from the 40’s to 70’s where global temperatures were dropping in which Winters were particularly harsh in the latter portion, the Northern Hemisphere has actually been cooling for most of time AGW theory said it should be warming. The cooling period was certainly larger than the warming period. Does this mean long term the NH is undergoing a cooling?
      Based on the evidence that view would be more valid than the AGW view.

      Bob Clark

  21. I’m a little late to the party – Herkimer et al around 8:16 am, this is an interesting article from [November] 2014. I have referenced it before, but it looks a lot like what Herkimer posted for the cold spot over NA, along with some hypotheses on why there is a cold spot on the central plains and the eastern coast:

    [NA = North America ? (Not North Atlantic, right?) .mod]

    • Thanks for that. At least some climate scientists are acknowledging that Winter temperatures have been dropping in the Northern Hemisphere. This is very concerning if the trend continues. At present rates, it could lead to Little Ice Age conditions in the Northern Hemisphere in just a few more decades, well before the 100 year timeframe the IPCC warns of harmful effects of AGW.
      The article has a link to this report:

      Asymmetric seasonal temperature trends.
      Judah L. Cohen,1 Jason C. Furtado,1 Mathew Barlow,2 Vladimir A. Alexeev,3
      and Jessica E. Cherry3
      GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L04705, doi:10.1029/2011GL050582, 2012

      The first sentence says:

      “Current consensus on global climate change predicts
      warming trends driven by anthropogenic forcing, with
      maximum temperature changes projected in the Northern
      Hemisphere (NH) high latitudes during winter.”

      So the actual cooling in the NH is in conflict with the theory of AGW. Leading AGW theorists are proposing theories to explain it, but this is ANOTHER area where the consensus predictions of AGW are contradicted by evidence. This fact still has not filtered down into the public discussion on the issue.

      Bob Clark

  22. I personally would like to see annual, seasonal and monthly figures of temperatures reported by continent rather than global and hemispheric . We should be more aware to what is happening in our neck of the woods. Berkeley Earth is way ahead of the other temperature data collectors in this approach . It makes little sense for NOAA to report global warming figures for the globe and yet fail to tell Americans year after year that their continent has been cooling and not warming at all for almost 20 yeas now . We should have figures for North America at the minimum. Perhaps dr Spencer could do the same at UAH

  23. I remain astonished at the fixation of those who work with climate data, especially temperatures, on linear trends. There is little to suggest that climate, or perhaps any other “natural” phenomenon, has much to do with linearity on almost any scale. We all know this from everyday experience, as has been pointed out in an earlier posting.

    Conventional climatologists seem to me to use every available technique to deny the possibility of abrupt change in measured climate parameters. Why should this be? Maybe because the annual average concentration of CO2 in the atmosphere increases effectively in a linear manner, Its forcing properties presumably run in close step with its concentration, therefore step changes in climate are impossible. It follows that only well-behaved models can be contemplated. Thus step changes are ignored, even if they are detected or obvious. Smoothing holds sway and inconvenient observations are soothed away by the unctions of averages and linear trends. Life just isn’t like that. Get real!

    A linear fit is just fine if the underlying data on the scale in question are clearly, graphically, linear. Otherwise the trend is merely a convenience, not a serious attempt to deduce anything of real value.

  24. “Conventional climatologists seem to me to use every available technique to deny the possibility of abrupt change in measured climate parameters. Why should this be? ”

    That is a very good question. Could be an entire topic actually.

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