A comphrehensive comparison of GISS and UAH global Temperature data

Part 1 of Comparison of GISTEMP and UAH MSU TLT Anomalies

Guest Post by Bob Tisdale

I originally started this comparison by looking at the differences between OI.v2 SST and the UAH MSU Lower Troposphere Temperature (TLT) anomalies for the same ocean segments. Since OI.v2 SST data has been used by GISS for their GISTEMP product since December 1981, I decided to add another comparison: GISS Land Surface Temperature (LST) versus UAH MSU TLT for the same continental land segments. Then I added one last comparison, which is the subject of this post.

Note 1: The data illustrated in the following graphs are as I downloaded them from the KNMI Climate Explorer website. I made no effort to offset either dataset in the comparative graphs so that the two curves rested on one another. The graphs will show that GISTEMP anomalies are higher than UAH MSU TLT anomalies. This is a function of base years. Focus on the trends and the shapes of the curves, not the location of the curves.

Figure 1 is a comparison of Global GISS Surface Temperature (GISTEMP) and UAH MSU Lower Troposphere Temperature (TLT) anomalies. Both datasets have been smoothed with 12-month running-average filters.
http://i41.tinypic.com/34ryski.jpg
Figure 1

Similar graphs always create speculative comments about the basis for the differences between GISS and UAH data. In this post, I’ve segmented the globe, Figure 2, to locate the areas with the largest differences, in an effort to narrow the possible reasons for those divergences. The coordinates used are listed on the graphs. I’ve plotted the data and added the linear trends, but I have not speculated about the causes for the differences in the data for the smaller global areas.
http://i40.tinypic.com/511opd.jpg
Figure 2

Note 2: GISTEMP data through the KNMI Climate Explorer is available with 250 km and 1200km smoothing. The graphs in the post use the 1200 km smoothing, which is the smoothing presented by GISS in their GISTEMP product. Figure 2, however, is the May 2009 GISS Global Temperature Anomaly map with 250km smoothing. Grey areas indicate locations with no data. These are the areas infilled by the 1200 km smoothing.

Note 3: Also keep in mind that the MSU TLT data reaches to 82.5N and 70S. The approximate locations of those latitudes are shown in Figure 2. UAH also fills in the polar data. On the other hand, MSU data has better global coverage in other areas where surface station data is lacking.

Note 4: And for the last note before looking at graphs and EXCEL-calculated trends, keep in mind that GISTEMP and UAH MSU TLT represent datasets made up of different variables. GISTEMP is composed of Sea Surface Temperature (SST) and of Land Surface Temperature data based on surface station readings. The UAH MSU TLT data represents the temperature of the lower troposphere.

COMPARISONS

Figure 3 illustrates GISTEMP and UAH MSU TLT anomalies for the Arctic, 65N to 90N. The GISTEMP linear trend for the period is 0.0595 deg C/decade while the UAH MSUTLT data has a linear trend of 0.0461 deg C/decade. Note how the GISS data exaggerates (or the UAH MSU data suppresses) the variations, especially after mid-2004.
http://i43.tinypic.com/1zp1q8j.jpg
Figure 3

The North America Plus datasets, Figure 4, also include the Eastern North Pacific and the majority of the North Atlantic. The trends are significantly lower than the Arctic datasets, as would be expected. The linear trend for the UAH MSU TLT data (0.0185 deg C/decade) is greater than the trend for the GISTEMP data (0.0159 deg C/decade).
http://i43.tinypic.com/4in94x.jpg
Figure 4

The South America Plus datasets, Figure 5, also show a UAH MSU TLT linear trend (0.063 deg C/decade) that is higher than the GISTEMP trend (0.05 deg C/decade). These datasets also include major portions of the eastern South Pacific and western South Atlantic. Both linear trends are again significantly lower than the North American Plus datasets. Note the dominance of the ENSO signal in the South American Plus data.
http://i42.tinypic.com/ohpnb5.jpg
Figure 5

The Europe Plus datasets show the highest trends of those examined in this post. This should be due to the impact of the North Atlantic on Europe. As illustrated and discussed in my post “Putting The Short-Term Trend Of North Atlantic SST Anomalies Into Perspective”, the linear trend of the North Atlantic SST anomalies is more than 2.5 times the dataset with the next highest trend. The GISTEMP trend (0.429 deg C/decade) for the Europe Plus dataset is slightly higher than the UAH MSU trend (0.379 deg C/decade).
http://i39.tinypic.com/x29niv.jpg
Figure 6

The difference in linear trends is greatest in the Africa Plus datasets, Figure 7. The GISTEMP linear trend at 0.194 deg C/decade is more than twice the linear trend of 0.093 deg C/decade for the UAH MSU data.
http://i43.tinypic.com/2iszbjt.jpg
Figure 7

For the Asia Plus subsets, Figure 8, the GISTEMP linear trend (0.256 deg C/decade) is also higher than the UAH MSU linear trend (0.179 deg C/decade). The Asia Plus datasets have the second highest linear trends of the areas illustrated in this post.
http://i41.tinypic.com/maudqf.jpg
Figure 8

The comparison of the Australia Plus datasets, Figure 9, illustrates another occasion when the GISTEMP linear trend (0.076 deg C/decade) is less than the USH MSU linear trend (0.096 deg C/decade).
http://i39.tinypic.com/2mrwtja.jpg
Figure 9

The first thing that stands out in the comparison of Antarctic datasets is the difference in the signs of the linear trends. The GISTEMP data show a positive trend of 0.048 deg C/decade, while the UAH MSU data show a negative trend, -0.091 deg C/decade.
http://i42.tinypic.com/an27et.jpg
Figure 10

The Antarctic datasets are also the noisiest of those illustrated in this post. But the real curiosity is the timing of the mid-to-late 1990s spike in the GISTEMP Antarctic data. At first glance, it appears to be a result of the 1997/98 El Nino. But the spike is more than a year early. In Figure 11, scaled NINO3.4 SST anomalies have been added to the comparative graph of Antarctic Plus GISTEMP and UAH MSU TLT data. The spike in the GISTEMP Antarctic data is not a response to the 1997/98 El Nino.
http://i41.tinypic.com/ngqeqq.jpg
Figure 11

Figure 12 illustrates the GISTEMP Surface Temperature and the two components of it: GISTEMP Land Surface Temperature, and OI.v2 SST data for the Southern Ocean. The source of the anomalous spike in the mid-1990s is the GISTEMP Land Surface Temperature data, not the SST data.
http://i40.tinypic.com/64dqft.jpg
Figure 12

Note 5: The GISTEMP Surface Temperature data from 90S to 60S is clearly dominated by the GISTEMP Land Surface Temperature data, though the surface area of the Southern Ocean (20.3 million sq km) is greater than the land mass of Antarctica (14.0 million sq km). This appears to be a function of Southern Hemisphere sea ice area, which can vary from 1.5 to 16.5 million sq km over the course of a year. During the winter, sea ice area increases. The land surface area then becomes greater than the sea surface area, making it the dominant dataset.

CLOSING COMMENT

I do not recall any discussions of a 1996 spike in the GISTEMP Antarctic surface temperature data. I have double-checked to assure I downloaded the data correctly. However, I have not tried to confirm whether or not the 1996 spike occurs in the individual Antarctic surface station data available from GISS:
http://data.giss.nasa.gov/gistemp/station_data/

A gif animation of the annual GISTEMP maps, Figure 13, does show elevated Antarctic surface temperatures in 1996.
http://i39.tinypic.com/2mwdopx.gif
Figure 13

SOURCE

THE GISTEMP Surface Temperature, GISTEMP Land Surface Temperature, UAH MSU TLT, and OI.v2 SST data are available through the KNMI Climate Explorer website:http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere

Posted by Bob Tisdale at 7:02 AM

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68 Responses to A comphrehensive comparison of GISS and UAH global Temperature data

  1. Adam says:

    Interesting that the UAH “North America plus” trend is greater than GISS. So, how can poor siting and UHI be exaggerating North America/US warming when a supposedly more accurate and representative satellite dataset actually has a greater trend?

  2. ohioholic says:

    I would say that the dominance of the Nino spike in the UAH trend pulls it upwards. The difference is only .0026C, and the Nino spike (1/30 or .0333) multiplied by the .7C swing in temperature over 2 years gave me .011667. I wouldn’t venture to say that it is unreasonable that the trend went higher because of the higher severity of the spike.

    Not being very exact here, just threw my eyeballs at it.

  3. ohioholic says:

    That is, the difference in the trends is only .0026C, barely a difference, really.

  4. tokyoboy says:

    I’d love to see the trend comparisons after reasonable correction for El Chichon & Pinatubo coolings.

  5. gt says:

    Alright, we can agree that there’s an upward trend for temperature. Any proof that it’s caused by anthropogenic CO2 output?

  6. Mike McMillan says:

    When we do graphs, any chance of doing .gif’s or .png-8′s instead of .jpg’s? Jpg’s are blurrier for computer generated stuff, and have larger file sizes.

    And I still think GISS hand-adjusted their 1998 value downward so they could top it in the future.

    Not that I don’t trust them or anything.

    REPLY:
    PNG’s at 24 bits is my choice, they reduce better when sized to fit. GIF’s and 8 bit PNG’s get crunchy edges. – Anthony

  7. Mike McMillan says:

    REPLY: PNG’s at 24 bits is my choice, they reduce better when sized to fit. GIF’s and 8 bit PNG’s get crunchy edges. – Anthony

    Aye, they do. A 24 bit png shouldn’t be much larger than an 8-bit, since I believe they all use RLE encoding and graphs have lots of white runs, even the spaghetti ones. I’ll have to check some day.

  8. paul maynard says:

    Some naive question.

    If the GISS dataset has the various problems described here and at surfacestations.org, why on an eyeball basis does it follow UAH so closely apart from the step difference?

    What is the right correction for the ENSO in 98. In otherwords, had it not happened, what wold the record for th past 20 years look like. I realise that this is stupid as ENSO is here to stay but it is important to try and find the underlying trensd if it is really there.

    Regards

    Paul Maynard

  9. Bob Tisdale says:

    Adam: You asked, “So, how can poor siting and UHI be exaggerating North America/US warming when a supposedly more accurate and representative satellite dataset actually has a greater trend?”

    With what has been presented so far, there’s no way to answer to your question. The graphs compare data for only the past 30 years, not for the entire term of the instrument temperature record. Also, as you can see in Figure 2, the datasets you’re drawing your conclusion from include large portions of the Atlantic and Pacific Oceans. Would you like to hold that question for Part 2 of this series? All you’ll have to do is cut and paste the same question from this thread to that one. I may not be able to answer it then to your satisfaction, but, at least, it will be a more appropriate place for it since we’ll be looking at land surface temperatures.

  10. Bob Tisdale says:

    Mike McMillan and Anthony: I’ll be happy to change formats for future posts, but I copy and paste the graphs from EXCEL to MS Paint and I only have one png choice in Paint. There’s no selection for 24 bits. Could you recommend some other image software?

    Reply: Gimp is free and open source and very powerful. ~ charles the moderator

  11. David Corcoran says:

    Man, with the Africa Plus dataset, GISS is shooting for the sky! Most of the variance is there. What could lead to such a large variance with sattelite data there in particular? Few and poor-quality stations? Large drop off?

  12. Bob Tisdale says:

    paul maynard: You asked, “What is the right correction for the ENSO in 98. In otherwords, had it not happened, what wold the record for th past 20 years look like. I realise that this is stupid as ENSO is here to stay but it is important to try and find the underlying trensd if it is really there.”

    You’d really have to remove the ENSO signal from the dataset over the entire term. But that leaves those nasty step changes caused by significant ENSO events and the lingering residual effects of ENSO that no one seems to account for.

    The step changes and their causes are discussed in my two part post that Anthony ran back in January. Here are the links to my copies of “Can El Nino Events Explain All of the Global Warming Since 1976”:
    http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of.html
    http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of_11.html

    The upward steps can also be seen in the North Atlantic SST anomaly data:
    http://bobtisdale.blogspot.com/2009/02/there-are-also-el-nino-induced-step.html

    And the lingering effects of the 1997/98 El Nino is very visible in my post on the RSS MSU TLT Time-Latitude plots here:
    http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html

  13. Roger McEvilly says:

    I have a serious question concerning climate warming in the last few hundred years, that has been unable to be refuted at various global warming websites. It appears to explain a great deal about T trends, and concerns heat lag effects following a peak of solar activity in the mid 20 century:

    1) Average daily heat lags are around 2 hours after peak solar incoming rays (about 2-3pm, after a peak around noon). This relates to a lag around 20-25% of total time of warming from dawn.
    2) Average annual highest T occurs about 6 weeks after the longest day of the year, again around 20-25% of total warming trend since the winter solstice.

    My question is: when this 20-25% is applied to the total warming trend of the sun from around 1750-1950, suggests a lag heat effect of T of around 40-60 years, peaking around the early 2000s, which is exactly what is observed.

    This seems to me a simple and powerful explanation of the entire solar warming trend, inclduing the T flattening that is currently occurring, withouth needing to invoke C02.

    Also, the lag effect of 40-60 years after peak solar activity shows more warming in the latter 20th century in the northern hemisphere, which is expected since there is less ocean in the northern hemisphere.

    Also, from this model, predictions can be made over the next 20 years, at least, since the sun has now waned slightly

    1) Northern hemisphere should not warm much over the next 20 years (well below IPCC forecasts). Current T flattening suggests ocean-land equilibrium has been reached in the northern hemisphere.
    2) Southern hemisphere T may continue to warm slightly, since the larger area of ocean may still exhibit a heat lag effect.
    3) Overall T should not increase much over the next few decades, if the sun is dominating climate change since ~1750-2000s.

    Note also: flattening of T around the 1950-70s relates to absorption by the oceans, paralleling a flattened, sustained peak in solar activity. Lag heat then kicked in from the 1980s-2000s. This heat lag effect should be now, largely over.

    I have never seen this conceptual model mentioned or debated, that is:

    that the lag heat effect in the latter 20th century relates to the ENTIRE warming trend of solar activity since ~1750-1950, ie, the total area under the curve of rising solar activity since 1750, ( and including flatenned solar activity since 1950), and not short term solar activity peaks and troughs, as depicted in various research papers (eg Usoskin 2005, Haigh 2003 etc).

    This model could explain much, including why many global warming websites point to the period 1978-1998 as being unexplanable by flattened solar activity, withouth examining the longer term heat lag effect on earth of about 40-60 years, from the ENTIRE warming trend from ~1750-1950.

    Could a serious scientists have a look at this. Every day on earth this time lag of 20-25% occurs, in average daily peak T.

  14. jmrSudbury says:

    “gt (21:50:02) : Alright, we can agree that there’s an upward trend for temperature.”

    You would be hard pressed to find anyone who does not agree that there was an upward trend in the 80s and 90s. — John M Reynolds

  15. Allan M R MacRae says:

    Thanks for this Bob,

    From previous comparisons of global ‘average’ temperature using UAH satellite LT (Lower Troposphere) and Hadcrut3 ST (Surface Temperature) , I concluded that there was a ~0.07 C/decade warming bias in the Hadcrut3 ST versus the UAH LT.

    This is best viewed in Fig. 1 at http://icecap.us/images/uploads/CO2vsTMacRae.pdf

    How does this compare with your analysis using UAH versus GISS?

  16. Bob Tisdale says:

    Allan M R MacRae: You wrote, “From previous comparisons of global ‘average’ temperature using UAH satellite LT (Lower Troposphere) and Hadcrut3 ST (Surface Temperature) , I concluded that there was a ~0.07 C/decade warming bias in the Hadcrut3 ST versus the UAH LT,” and asked, “How does this compare with your analysis using UAH versus GISS?”

    Subtracting the trends illustrated in Figure 1, it appears that GISS adds ~0.035 deg C/decade. Keep in mind, though, that the Hadley Centre data also includes an SST step change in 1998 due a change in data sources. I showed and discussed that step here:
    http://bobtisdale.blogspot.com/2008/12/step-change-in-hadsst-data-after-199798.html

    The supplier states, “ICOADS is supplemented by NCEP Real-time data (1991-date; limited products, NOT FULLY CONSISTENT WITH ICOADS,” and it looks as though the Hadley Centre didn’t fully correct for those differences.

    Regards

  17. tallbloke says:

    Bob Tisdale (01:16:30) :
    I only have one png choice in Paint. There’s no selection for 24 bits. Could you recommend some other image software?

    Reply: Gimp is free and open source and very powerful. ~ charles the moderator

    Fireworks is damn good too.

  18. Nick says:

    Why not do an analysis of temperature differences against population density?

    Chances of a correlation are high

  19. peter_ga says:

    Interesting how Asia and Africa have much greater GISS trends, suggesting strong UHI effect, while developed continents have GISS trends less than the satellite data, suggesting the old data was contaminated by poorly sited thermometers, and modern day attention to placement is over-countering this effect.

    GISS obviously needs to factor in some sort of “Anthony Watts coefficient” to balance out the trend.

    Somebody ought to graph GISS global warming trend verses GDP per capita for various countries. We may have stumbled on a brand new developmental index.

  20. tallbloke says:

    Roger McEvilly (02:50:02) :

    My question is: when this 20-25% is applied to the total warming trend of the sun from around 1750-1950, suggests a lag heat effect of T of around 40-60 years, peaking around the early 2000s, which is exactly what is observed.

    Roger, my graphs showing cumulative totals of solar activity may be of some interest to you.

    http://1.2.3.9/bmi/s630.photobucket.com/albums/uu21/stroller-2009/th_ssa-sst-ssn.jpg

    http://1.2.3.13/bmi/s630.photobucket.com/albums/uu21/stroller-2009/th_sst-nino-ssa.jpg

  21. John says:

    In several regions, the El Nino spike brings the two records much closer together, especially N America, Africa, and Australia. Does this suggest that when measuring a phenomenon which propagates from the atmosphere down to the surface, the systems are in close agreement, but when measuring temps which propagate from the land surface upward, they are not? If there is such a suggestion, would that be evidence that the urban heat island effect has not been adequately compensated for? My lack of expertise doesn’t allow me to make such a judgment, but I would like someone with more expertise to chime in.

  22. wws says:

    I don’t know the actual error of measurement for these readings, but I’m willing to bet that it is greater than .0026 degrees C.

    It is way too easy for everyone these days to get carried away with the false precision that digital analysis and graphing does, but the fact remains – you can NOT have a significant result that is less than the underlying error in measurement!

  23. DR says:

    HELLO!! Satellites will see the effects of UHI and land use change, but they cannot distinguish between whether a thermometer is placed on a rooftop, near a bbq or in a grassy field.

    Some will say removing those effects will lower the global average temperature significantly, and at the same time validate the CO2 AGW hypothesis for the troposphere warming at a faster rate than the surface.

    Not so. Think about it.

  24. Bob Tisdale says:

    John: You asked, “In several regions, the El Nino spike brings the two records much closer together, especially N America, Africa, and Australia. Does this suggest that when measuring a phenomenon which propagates from the atmosphere down to the surface, the systems are in close agreement, but when measuring temps which propagate from the LAND SURFACE upward, they are not?” (Caps added)

    The graphs above also include sea surface temperature data and TLT Data over oceans. With that in mind, there are different processes taking place in the oceans versus the troposphere after ENSO events. This is very apparent in the comparison of North Pacific SST anomalies to TLT anomalies over the same portion of the North Pacific Ocean. But that’s getting ahead of things. It’ll be on Part 3 of this post.

  25. tarpon says:

    Why doesn’t anyone ask how much reduction in the global temperature do we get for each trillion in new taxes. Seems like the simple thing to do … end the argument quickly.

  26. Tim Clark says:

    gt (21:50:02) : Alright, we can agree that there’s an upward trend for temperature.”

    We agree. But that’s irrelevant. For the “most sophisticated and spatially intensive weather collection system in the world” ie. North America, the average increase of the two data sets is 0.172 deg C/century. Tell me, how much will that increase sea level, cause starvation, kill polar bears, cause cancer, induce infertility, etc., etc., etc. From this analysis, the problems between the two datasets reside in areas with poor spatial distribution (for example, gray areas in Africa, Arctic), where Gisstemp imposes a flawed fill-in technique (similar to Steig et. al.).

  27. tallbloke says:

    Africa truly is the ‘heart of darkness’ where GISS is concerned.

  28. Mark Nodine says:

    A small correction,but for the Arctic graphs, either the slopes on the graph are mysteriously per decade, or the text should read 0.595 deg C/decade and 0.461 deg C/decade (i.e., 10x what it currently reads).

  29. GlennB says:

    jmrSudbury (03:11:32) :

    “gt (21:50:02) : Alright, we can agree that there’s an upward trend for temperature.”

    “You would be hard pressed to find anyone who does not agree that there was an upward trend in the 80s and 90s. — John M Reynolds”

    Not sure what you really mean here, but as to the upward trend in the 80 -90s, I’m hard pressed to find much of an upward trend at all, at least until the 1998 El Nino.
    http://wattsupwiththat.files.wordpress.com/2008/09/uah_august2008.png

  30. igsy says:

    Very informative post, Bob. Any chance you are able to dissect Asia into north and south? I would be interested in the difference in trends that can be attributed to North Asia and Africa combined. It has been widely noted elsewhere that the former USSR record has problems such as rural-to-urban station dropout, and the African history is as much a guess as it is science (and should probably be omitted from the ‘global’ temperature history series).

  31. Tim Clark says:

    Tim Clark (08:01:46)

    Opps, forgot to say; good analysis Bob! I’m counting on you to keep me posted on ENSO. I’ve got a lot of money riding on it. ;~0

  32. gary gulrud says:

    Another thorough, sober and informative analysis, thanks.

  33. Bob Tisdale says:

    Igsy: You asked, “Any chance you are able to dissect Asia into north and south?”

    In the second post, I’ve provided a look at Asia in general and that Soviet Union “Hot Spot”.

    You wrote, “I would be interested in the difference in trends that can be attributed to North Asia and Africa combined.”

    As noted in this post, I use the KNMI Climate Explorer for the data. It’s a coordinate-based system. The UAH MSU TLT data at KNMI, unfortunately, is not divided into Land or Ocean data, so I can only grab portions of each continent, in an effort to reduce the effects of any mixing of Land or Ocean data. Therefore, for the land and ocean comparisons, Parts 2 and 3 of this post, I can’t combine two continents without getting ocean data in there too.

  34. timetochooseagain says:

    A lot of instances of “degrees per decade” need to be changed to “per annum” or multiplied by ten.

    DR (06:26:48) :

    Uh, no. Satellites measure bulk atmospheric temps. Those effects would largely be restricted to the surface and not far beyond certain areas. Satellite would be negligibly influenced by them.

    Adam (21:02:08) : I wouldn’t be surprised if that region had the best data, however it should be remembered that trends higher up are generally supposed to be greater.

    Bob:
    A real interesting result would be if you scaled the satellite and surface data so that their interannual variability matched. ENSO events appear to have a larger impact aloft for instance. I try to make use of this with HadCrut and UAH annual data to figure out what the biases in the data are:
    http://www.climateaudit.org/phpBB3/viewtopic.php?f=3&t=740

    My conclusion is that the satellite data indicate significant bias in the surface data.

  35. Steve Hempell says:

    One thing that jumps out at me right away is how much influence El Nino and it’s aftermath (as outlined by Bob) has influenced the linear trend of temperature. Take away the El Nino peak alone (never mind the aftermath) and the trends are considerably less (for UAH). Look at Africa, SA, Australia, even the Arctic. By eyeballing it, they have insignificant trends are even negative trends pre ~ Oct 1997. Europe seems to run to a different drummer – AMO perhaps. Maybe I’m biased so time to try and repeats Bob’s work looking at pre/post El Nino.
    Eagerly awaiting parts 2 and 3.

  36. Flanagan says:

    Hey, have you seen the series of record high temperatures in Texas? The highest daily temp in San Antonio and Austin were broken, and it’s going to continue for a week or so…

    REPLY: Yes and I also heard about the record cold and continued snow cover in Churchill, but I didn’t write about that either. Nice try though. – Anthony

  37. Pamela Gray says:

    The likelihood of an El Nino or La Nina condition lasting only once would be an unsupportable idea. These events probably seasonally echo into the future for quite some time. The warm or cool pool eventually works its way to other parts of the ocean and has an echo affect. Until we know just how much subsequent temp changes are due to a previous oceanic oscillation, we won’t know how much of the data to remove in order to find a signal that is caused by something else. In my opinion, the subsequent stairstep rises or falls that we see are echoes (IE off-set) of oscillation influences. The sudden sharp and significant changes are due to their onset. The rest of the noise is probably related to regional and local complex weather chaos. Given the complex nature of endogenous natural weather pattern drivers, finding ANY signal that is tiny would be harder than finding a blond hair in a straw stack.

  38. Pieter F says:

    It would be interesting (and fun) to overlay Dr. Hansen’s prediction from his 1988 congressional testimony on Figure 4. As I recall, he insisted we would have an anomaly of around 1.1°–1.2°C by now.

  39. Tom in Texas says:

    Flanagan (11:04:30) : “Hey, have you seen the series of record high temperatures in Texas? The highest daily temp in San Antonio and Austin were broken, and it’s going to continue for a week or so…”

    I have, for the last year or so, been trying to convince my daughter (in Austin) that gorebull warming is a con.

    Right now in San Antonio it is 101°F (heat index 105). Has been triple digits for the last week, and also forecast to continue. The local utility set a record yesterday for energy usage. I’d be hard pressed right now to convince her it is just weather, but its been hotter – In June 1998 Austin was 111°F and San Antonio 107°F.

  40. John Galt says:

    Flanagan:

    That’s just weather.

    What does it prove? Just because it’s hot somewhere doesn’t mean anything. What’s causing the heat? Show us some direct evidence that it’s due to greenhouse gas emissions.

    Hot weather is not an indicator of AGW. Neither is climate change. That fact that someplace is unusually hot or the climate is changing means absolutely nothing.

    And the places where there is record cold? Well, it sure ain’t cold masking the warming, either!

  41. Larry Hamlin says:

    What these graphs clearly show is post January 1998 stable and declining global temperatures during the period of greatest ever manmade CO2 emissions growth. According to EIA data about 85% of the world’s growth in CO2 emissions since 1990 occurred after January 1998. Yet despite this huge CO2 emissions growth driven by the developing nations actual global temperatures moved in the wrong direction compared to strongly increasing temperatures predicted by IPCC climate change models. The models are wrong so the so called science underlying the models is wrong. We need to stop pretending otherwise.

  42. Flanagan says:

    Excuse me Anthony, but I wasn’t criticizing your reporting (or not) of these events at all, I was simply mentioning it. BTW, which Churchill are you talking about? Following weather underground, I found a Churchill Kansas (35 °C – 4°C above average), a Churchill Pennsylvania (32 °C – 5 °C above average) and Churchill Manitobe (CA – 7 °C, 4°C below average)?

  43. Flanagan says:

    But maybe what you could have reported is the 2 months-long heat wave in India, that alreaky killed hundreds of people…

  44. Richard M says:

    Flanagan (11:04:30) :

    “Hey, have you seen the series of record high temperatures in Texas? The highest daily temp in San Antonio and Austin were broken, and it’s going to continue for a week or so…”

    You complain when record cold weather is reported. Now, you report record warm temps. Does the word hypocrite mean anything to you?

    BTW, this warm weather is nice where I live under the same ridge in the jet. After temps 20+ degrees below normal earlier this month a nice 10-15 degrees above is welcome. We may even get back to normal for the month. Could do with a little less humidity though.

  45. Pamela Gray says:

    I think posts of daily updates of weather, be it hot or cold, should have a rule attached. If you wanna post it, tell us why this local event is happening weather wise. If you want to talk about weather, show us you know something about weather drivers.

  46. Bob Tisdale (01:16:30) :

    Mike McMillan and Anthony: I’ll be happy to change formats for future posts, but I copy and paste the graphs from EXCEL to MS Paint and I only have one png choice in Paint. There’s no selection for 24 bits. Could you recommend some other image software?

    Try IrfanView. http://www.irfanview.com/
    It is free, very lightweight and does all formats you can think of, plus some more. Very nice for resizing and many other tasks. I have used it for years, cannot live without it.

  47. Bob Tisdale says:

    Tim Clark: You wrote, “North America, the average increase of the two data sets is 0.172 deg C/century.”

    That should be 1.72 deg C/century. My mistake in the text. The per annum figures in the equations are correct. I’ve corrected the text in the version on my website.

    timetochooseagain and Mark Nodine:

    Thanks for picking up my typos on the trends. Arctic and North America were incorrect in the text of the post. They’ve been corrected in the versions at my website. That’s what I get for proofreading before 7:00am.

  48. Flanagan says:

    Hey Pamela, are you still keeping your bet about the northwest passage not opening? Because 1/3d of it is already free, and the rest doesn’t look nice.
    http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png

  49. Frederick Michael says:

    There’s something wrong with these graphs — look at the horizontal axis. Clearly, they display slightly less than 30 years of data, instead of slightly more (as Jan 1979-May 2009 would imply). If the endpoint is May 2009 (which seems to make sense) then a consistent interpretation of the axis means they start in January 1980.

    Right???

  50. Bob Tisdale says:

    Frederick Michael: You wrote, “There’s something wrong with these graphs — look at the horizontal axis. Clearly, they display slightly less than 30 years of data, instead of slightly more (as Jan 1979-May 2009 would imply). If the endpoint is May 2009 (which seems to make sense) then a consistent interpretation of the axis means they start in January 1980.”

    Nothing’s wrong with the graphs. Refer to the note directly above the dates in the title block of each graph. The data have been smoothed with 12-month running-average filters. This “shortens” the data at each end. The actual period covered can be seen in the start and stop points of the trends.

    Thanks for keeping an eye out for errors, though.

    Regards.

  51. Bob Tisdale says:

    Pieter F: You wrote, “It would be interesting (and fun) to overlay Dr. Hansen’s prediction from his 1988 congressional testimony on Figure 4. As I recall, he insisted we would have an anomaly of around 1.1°–1.2°C by now.”

    Lucia (The Blackboard) has compared Hansen and IPCC predictions versus the temperature record in numerous posts. Here’s a link:
    http://rankexploits.com/musings/

    Regards

  52. braddles says:

    Frederick Michael,

    I think that, with a 12-month running filter, the first 6 months and last months of the record are not presented because they don’t have a full 12 months to use for calculation. The last point would be Nov 2008 which is the average of June 2008 to May 2009.

  53. Bob Tisdale says:

    timetochooseagain: You wrote, “Bob: A real interesting result would be if you scaled the satellite and surface data so that their interannual variability matched. ENSO events appear to have a larger impact aloft for instance.”

    For the South Atlantic and North Pacific, there are significant differences between SST anomalies and TLT anomalies over the same ocean areas during the 1997/98 El Nino. The differences are so great there’s no reason to scale and overlay them.

  54. Jeff Alberts says:

    Flanagan (11:04:30) : “Hey, have you seen the series of record high temperatures in Texas? The highest daily temp in San Antonio and Austin were broken, and it’s going to continue for a week or so…”

    And while mowing my lawn today at 3pm, while wearing heavy pants, tshirt and sweatshirt, I was still cold, since the outside temp was barely 60. That’s a little north of Seattle.

    Global Warming Ain’t Global. The heat just gets moved around from place to place.

  55. Frederick Michael says:

    Bob Tisdale (15:30:31) :

    Nothing’s wrong with the graphs. Refer to the note directly above the dates in the title block of each graph. The data have been smoothed with 12-month running-average filters. This “shortens” the data at each end. The actual period covered can be seen in the start and stop points of the trends.

    Good point! I missed that. The endpoint of the regression lines is another clue. We return to your regularly scheduled broadcast.

  56. Allan M R MacRae says:

    timetochooseagain (10:27:01) :

    From you graphs and trendlines:
    0.0152 -0.0087 = 0.0065 C per year
    = 0 0.065C per decade
    versus my 0.07C per decade, posted at 03:26
    Close enough.

    The logical extension is that there has been NO net global warming since 1940, despite an ~800% increase in humanmade CO2 emissions.

    See
    http://www.iberica2000.org/Es/Articulo.asp?Id=3774

    Regards, Allan

    P.S. The warmists better find another scary story, and fast. Perhaps ocean acidification? Either that, or start saying that increased CO2 causes global cooling. That will soon be easier to support than their current untenable hypothesis.

  57. Allan M R MacRae says:

    PPS – A very interesting observation is that CO2 lags temperature at all measured time scales – this subject has been discussed here and elsewhere.

    In fact, we don’t even know what truly drives the various changes in atmospheric CO2. Clearly nature dominates on a seasonal time scale.
    Seasonal variations in the far North range up to almost 20ppm per year, and are near zero at the South Pole. Then there is that pesky 2ppm annual average increase that the warmists are so excited about – but this has “gone negative” occasionally during ~recent periods of modest global cooling.

    What do we know?
    That increased atmospheric CO2 does not significantly drive temperature.

    What don’t we know enough about?
    If and how much temperature drives atmospheric CO2.

    See the 15fps AIRS data animation of global CO2 at
    http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003562/carbonDioxideSequence2002_2008_at15fps.mp4

  58. timetochooseagain says:

    Allan M R MacRae (18:53:25) : Well I don’t know about that-without satellites over the period I really don’t feel comfortable talking about what the biases are/might be during the pre-1979 period. What I do know is that the surface appears to have warmed very little in 30 years. Unless of course for some strange reason the surface could behave differently in relation to the atmosphere in the long term than the short term-or, I don’t know, maybe there really is some problem with the satellites. But if that is the contention, then the opponents of the satellites need to publish explaining what could be wrong with them just as surface record critics have.

  59. Magnus says:

    I’ve noticed that the difference in trend between GISS and RSS is almost zero. Until 1979 they probably had lots of UHI and stuff and Hansen may have a hard work to keep (and lose!) the positive bias they have acheived? They may need more powerful stuff than errors from some Finish weather stations? ;)

  60. Magnus says:

    Correction: “(and lose!)” –> “(not lose!)”

  61. Allan M R MacRae says:

    timetochooseagain (19:51:58) :

    Well I don’t know about that-without satellites over the period I really don’t feel comfortable talking about what the biases are/might be during the pre-1979 period.

    **************************

    Actually time, just use the 1940 to 1979 Hadcrut3 data as-is with no ‘UHI adjustment’, and you will reach my conclusion of ‘No global warming since 1940′.

    If you assume a UHI adjustment of 0.07C/decade, you will conclude ~0.3C of COOLing since 1940.

  62. dennis ward says:

    I don’t know if this has been suggested before but has anybody contacted the TV program ‘Mythbusters’ and asked them if they would do an experiment with three stations (or replicas) within about thirty feet of each other, with one in the sunlight all day, one in the shade at least half the day and another within spitting distance of an A/C unit, say. I’m sure there may be other factors to be considered as well but you get the basic idea.

    Surely this would prove the case better than anything else as to what effect UHIs have on temperature? And think of the publicity value.

    REPLY: There are no explosions in temperature measurement. – Anthony

  63. Flanagan says:

    Heat wave in Texas with new records set:
    http://edition.cnn.com/2009/US/weather/06/25/heat.wave/index.html
    also in New Orleans, there’s a “heat wave marathon” with people struggling to maintain enough power for conditioning
    http://blog.nola.com/tpmoney/2009/06/no_shortage_of_power_for_airco.html
    Temperatures will approach or exceed the century mark in Oklahoma
    http://www.kristv.com/Global/story.asp?S=10591487&nav=menu192_2

    This is all consistent with the NOAA predictions on summer anomalies, with the northwest and northeast having slightly cooler than average temps. But what happens in the rest of the world?

    120 die in unrelenting heatwave across India
    http://blog.nola.com/tpmoney/2009/06/no_shortage_of_power_for_airco.html
    North China wilts under scorching heatwave
    http://www.chinadaily.com.cn/china/2009-06/26/content_8324862.htm

  64. timetochooseagain says:

    Allan M R MacRae (20:54:42) :

    I wouldn’t assume linearity over time either ;)

    Still, its a good point.

    Magnus (20:29:26) :

    I’m not sure why everyone assumes that 1. The trends should be the same and 2. RSS is superior. Both are incorrect. The trend in the LT should be greater than near surface, and research suggests UAH is superior:

    http://www.agu.org/pubs/crossref/2008/2007JD008864.shtml

    Flanagan (01:23:49) :

    Say it with me now: W-E-A-T-H-E-R. It happens. Never draw broad conclusions from it (this goes for coolers to!)

  65. Bob Tisdale says:

    Charles the Moderator, tallbloke, and Carsten Arnholm, Norway: Thanks for the suggestions.

    Anthony: Thanks.

  66. Tim Clark says:

    The all time record (69) in Dallas of days over 90 deg was set in 1980. Let me know when we get there. The temp here in Kansas today is 104 deg. This is consistent with historical evidence of the 1930′s and with my prediction made on this blog that we are returning to that almost identical previous weather.

  67. dennis ward says:

    Anthony says there are no explosions in temperature measurement so I presume he means ‘Mythbusters’ would not be interested but there is certainly a great deal of heat generated on the subject.

  68. peter schoubye says:

    I can strongly recommend another excellent homepage:
    http://www.climate4you.com,
    It is edited and updated every month professor in physical georgrapy at Oslo University Ole Humlum and gives you all kinds of climate data objectively, easy to read and with no data picking.

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