Environment/Nature

2007 global temperature second hottest since 1880

2007 GISS data-map

On January 16, 2008, Dr. James Hansen of NASA’s Goddard Institute for Space Sciences (GISS) released the summation of temperature data for 2007 with apparently very little fanfare. Given the data collected by Dr. Hansen, the lack of fanfare itself might well be notable. But regardless, the data itself bears more public attention that it’s had.

2007 is now tied with 1998 as the second hottest year for global temperature in a century.

According to the the GISS 2007 summation press release online, all eight of the hottest years for global temperature have been since 1998, and 14 of the hottest years have been since 1990. The global temperature map (shown in image above – larger version available), the Arctic and Siberia had the greatest temperature increase, between 3 and 4 degrees Celsius. This heating was responsible for, or a direct result of, the smallest Arctic ice cap since records have been kept.

If you look closely at the eastern Pacific ocean in that map, though, you’ll notice a horizontal strip of blue right about the equator, indicating a strip of cooling. The 1998 temperature spike was caused by one of the hotter and bigger El Niños recorded – 2007 was as hot even though the Pacific Ocean had a La Niña cooling event instead. Not only that, but in 1998, total solar output was on its way up toward its solar maximum (a result of the solar sunspot cycle) instead of being pretty much at minimum solar irradiance (for this solar cycle) in 2007.

In other words, we had the second hottest year in the last century even though the sun’s output was low and the Pacific had a cooling La Niña event. Any bets what will happen in the next 5 years or so as the solar irradiance goes up, we have our next El Niño, and while greenhouse gas concentrations continue increasing?

Global heating skeptics said last year that the earth had already started cooling down – the data doesn’t support this conclusion. Skeptics have also said this year that the unusually cool January put the lie into global heating – given that 2007 was so hot even though there were cooling events, the data suggests that a cooler 2008 is entirely reasonable and even expected. And it’s not like a single year, or even two or 5 years of below average temperatures negate the fact that, as the image above shows, there has been a 30-year heating trend globally.

30 replies »

  1. Pingback: www.buzzflash.net
  2. You actually believe this crap? Haven’t you heard that the data was skewed? Google NASA global warming data flaw.

  3. Brainiac – actually, not only have I blogged about that very data error myself here (Changes in U.S. climate data do nothing to debunk global heating), but the link above discusses the corrected error itself. Allow me to quote it for you:

    The data processing flaw was failure to apply NOAA adjustments to United States Historical Climatology Network stations in 2000-2006, as the records for those years were taken from a different data base (Global Historical Climatology Network). This flaw affected only 1.6% of the Earth’s surface (contiguous 48 states) and only the several years in the 21st century…. In the contiguous 48 states the statistical tie among 1934, 1998 and 2005 as the warmest year(s) was unchanged. In the current analysis, in the flawed analysis, and in the published GISS analysis (Hansen et al. 2001), 1934 is the warmest year in the contiguous states (not globally) but by an amount (magnitude of the order of 0.01°C) that is an order of magnitude smaller than the uncertainty.

    In other words, the error affected only the contiguous 48 U.S. states, not the entire globe, and the error had no impact on the global temperature data.

    Feel free to look at this pair of graphs, where the data before the correction is graphed at the same time as the data after the correction. Please note that you can’t tell the difference between the before/after correction graphs on the global data.

  4. But. But. There’s a marginal error, so how can we trust the whole thing???!!! [/sarcasm]

    The lack of logic of some deniers – Denialists even, considering the almost religious conviction inherent – bothers me to no end. What really is so difficult about assuming there’s truth to it and doing something, even a small part, to offset it?

  5. What the wingnuts are doing is conflating weather with climate, that is, deliberately confusing relatively local/limited weather phenomenon with global climate measurements. The wingnuts are cherrypicking weather snapshots and trying to pass these off as representing the entire global climate picture.

    For instance, a global warming skeptic, who listens to Rush Limbaugh and watches Faux News, told me in the Fall of 2006 that the Atlantic Ocean waters were cooler than normal, so this disproved global warming.

    I, however, had read the actual article which reported in the several sentences following this information about the Atlantic being cooler than normal that the Gulf of Mexico and Caribbean Sea waters were warmer than normal.

    My prediction, therefore, for last years 2007 hurricane season: tropical depressions that formed out in the Atlantic would be hard-pressed to develop into monster hurricanes, while anything forming or making it into the Gulf of Mexico or Caribbean further to the South, due to the warmer-than-normal waters, would probably form into Category 4 or 5 hurricanes.

    Sure enough, the Atlantic tropical storm systems were relatively weak, while two tropical systems that entered the Caribbean became Category 5 hurricanes that hit Mexico. In the case of one of these 2007 Category 5 hurricanes, the Republican governor of Texas mobilized emergency measures in South Texas, just in case the tropical storm veered to the north.

    If this trend of cooler temperatures in the Atlantic (due to the melt-off of the freshwater ice up near the Arctic, I believe, with the Gulf Stream finally transporting this cooler water further south) and the warmer temperatures in the Gulf of Mexico and Caribbean continue, then this year’s hurricane season will probably look much like last year’s, but the Gulf Coast states may not dodge the bullet like they did last year. I expect some more Category 5 hurricanes in the Gulf of Mexico and the Caribbean this upcoming hurricane season, possibly impacting the Gulf Coast like Hurricane Katrina and Hurricane Rita did.

  6. ent- unless you can provide me proof when Hansen lied and fudged his data (which is the most serious charge you can ever lay at a scientist), you’re just engaging in an ad hominem attack.

    The January 2008 GISS data set mentioned at your second link is the on I’m talking about, but the image shown is January only. The other datasets show the other months, but the GISS data at Wattsupwiththat is a snapshot, and thus cannot be compared, as was done, accurately with the other datasets shown. And I’ve just pointed that out to Anthony Watts at his site.

    In addition, the HadCrut data Watts uses is both correct and misleading – the yearly variation shown in the actual HadCrut data does show a little cooling, but only 0.02 degrees, NOT the -0.595 degrees Watts shows. It’s the difference between a January-January snapshot (Watt’s use of the data) and a yearly average.

    The RSS data is missing 7% of the planet (it’s not as “global” as Watts says), and according to the yearly average temperature over the globe again, 2007’s average anomaly was actually GREATER than 2006, not less (2006 was .281 by my calculations, 2007 was .297 degrees C). Again, Watts is using January-January shapshots, NOT yearly averages.

    And yet again, my calculations on the UAH data show that Watts is wrong. 2006 had a anomaly of 0.260 yearly average, 2007 shows 0.282 degrees C.

    Fundamentally, Watts presents a difference from one year to the next that shows a trend toward cooler temperatures in 2008, but his data is based on January 2007 vs. January 2008 snapshots instead of yearly averages. And so his conclusions are biased.

    And given that the “4 Sources say ‘globally cooler'” link is almost verbatim from Watts’ site, it’s just as biased as Watts’ own conclusions are.

    Feel free to forward this on to Watts himself – I’d love to hear his explanation for why he’s right when three of the 4 datasets he uses contradict his conclusions.

  7. Not sure I’m following you. True, one of the three graphs is based on two data points, but the other three are not and they all show a fairly steady decline throughout the year. It stands to reason that if the total temperature dropped by 6-7 tenths during that year, then the average temperature for the year would be roughly half that, or 3-3.5 tenths, still a whopping amount compared to the few hundredths a year that set the global warming alarmists atwitter.

    As for the credibility of the GISS data and how it has changed over time, there is a lot of discussion on the Internet. Here’s a starting point:

    Should NASA climate accountants adhere to GAAP?

    Check out the rest of the website. Mr. McIntyre seems to really be on top of the issues. I would trust his conclusions far more than the politicians, entertainers, and obviously politically compromised scientists at the UN.

    As for Hansen’s objectivity, there’s a lot of talk about that, too, for example:

    Flawed NASA Global Warming data paid for by George Soros

    I don’t know about the Soros claim; I haven’t seen convincing evidence, but how many objective nose-to-the-grindstone scientists do you know of who spend their time on the road giving 1400+ speeches and interviews? He would seem to have an axe to grind and partisan political forces funding him in the grinding.

  8. Ent – You seem to be arguing tht If the temperature increases .5 degrees total over 11 months but then drops 1.5 degrees in December, the average temperature change for that year should be -0.5 degrees. In fact, it should be +0.33 degrees (334 days of +0.5 degrees plus 31 days of -1.5 degrees, divided into 365 days to get the average). The same is true of the datasets you’re misreading, although the changes aren’t as blatant as my intentionally extreme example. Three of the datasets show that the yearly average was higher than 2006, and the fourth shows 0.02 degrees of cooling.

    What’s even more interesting is that the temperature drops shown in 2007 are actually smaller than the drops in 2006. and there most certainly wasn’t 12 months of cooling – there was 1 month of heating (J), 4 months of cooling (FMAM), followed by 3 months of heating (JJA), followed by 4 more months of cooling (SOND). And this pattern was nearly identical for all four datasets.

    Temperatures were higher on average than 2006 until November and December, when the La Nina that started in July really took off. That is why the yearly average for 2007 contradicts Watts’ conclusions. And let’s not forget that January 2007 was one of the hottest Januarys on record, so Watts choose, perhaps unintentionally, the hottest month of 2007 from which to baseline his erroneous conclusion.

    I’ve been around McIntyre’s site several times, and he’s generally got his ducks in a row like Watts generally has his. And I applaud their attention to details and how they help improve the state of climate science and correct data errors. But they can make errors, be misquoted, and misinterpret data just like the scientists they’re criticizing can.

    This is, after all, why looking at multiple datasets, not just the GISS data, is so valuable. Each set of data has it’s own unique errors, biases, corrections, measurement techniques, etc.

  9. Can anyone explain why there appears to be a roughly 40 year period (1940 – 1980) where the temperature is not increasing and may actually be decreasing?

  10. Looking at these graphs it is tough to be convinced that there is any trend over the past 5 years. I guess we will have to see how the rest of 2008 plays out but unless there is a large bounce off the low in January 2008 then 2008 will be a cool year.

    Wattsupwiththat link

  11. Stillunconvinced – check out this link. It’s to the debunking I did last year where I discuss this very thing.

    Also, I discussed that exact Wattsupwiththat link in comments 9 and 11 above. Remember, though, that most of the graphs use different techniques to window and average the monthly data. Some use Jan-Dec yearly averages, some use moving averages of the last 12 months, others use windowed averages of the 2.5 years before and after with trapezoidal weighting (I think this is what GISS does). So you have to take the data and look at it using the same methods to make heads or tails of it.

    I’ll post some graphs using the base data myself in the next week or two and the put a link here in the comments to that post.

  12. Global warming is good! We need more of it!

    I asked my 14-yr old to think of the place in the world that is the “greenest” – that is, the most favorable for growth of vegetation. His answer – the Amazon rain forest. Okay, then, why is it the most favorable? Warm temperatures, lots of rain and water vapor in the air, and, of course, lots of carbon dioxide. For those of you listening at home, water vapor and carbon dioxide, in that order, are considered to be the two greenhouse gases most responsible for global warming. At this point, a light bulb went off over his head. He came to the same conclusion that I did – increased carbon dioxide that results in an increase in the global temperature is the best thing for vegetation. What’s good for vegetation is good for animals that live on the vegetation, and it’s good for the animals that live on the animals that live on the vegetation. Get it? An illustrative point: farmers in the Midwest USA are seeing some of the highest crop yields in history. So next time you think about global warming, think about it as vitamins for the Earth!

  13. longhorngopher:

    So on the one hand we have the massive majority of all the Earth’s climatological scientists, and on the other we have your 14 year-old?

    I’m reminded of Jimmy Carter’s nuclear proliferation chats with his daughter Amy…

  14. longhorngopher:

    So, the countries with lots of rain forest are the wealthiest, most productive countries in the world, right?

    The fact is, rain patterns will change across the globe. Some areas will be winners and some losers. But think of this: The infrastructure for farming — adequate topsoil, harvesting equipment, distribution outlets, storage facilities, etc. — is limited to only a few, arable spots in the whole world. If those places dry up, the world goes hungry. Well, at least the poor people go hungry.

    Adding rainfall to the Sahara desert will not make it fertile for centuries. And if adding rain to the Sahara is supposed to make up for subtracting rain from, say, the Ukraine, it’s not going to happen any time soon.

  15. Dammit, Brian, I just formed a new band….

    I guess my only option is to believe longhorngopher’s 14 year old and buy Hawaiian shirts for the group.

    Oh, did I mention this is terrifying…?

  16. Wow – nobody posts anything here for 2 months, and then my little entry causes a firestorm.

    Okay, let me address some of your comments.

    1. I was making 2 points with my post. First, people aren’t using common sense. The fact is that the earth has been warmer, far warmer, in the past than it is now, and, as far as I can tell, the planet wasn’t destroyed. Second, even if the earth is undergoing a dramatic climate change, how do we really know that that is a bad thing? Fact is, we don’t, which leads me to my second point.
    2. “Scientific consensus” is not science. Science, to put it in small terms that you can understand, is about being able to actually prove a theory by replicating results in a closed environment. Global warming theory is simply theory. Scientists cannot prove the cause(s) (they have ideas, theories, but no proof), cannot replicate results, and cannot predict the effects. Meteorologists cannot accurately predict today’s high temperature; how in the hell do you think they can project temperatures 50 years from now? Come on, use your brains, people.
    3. JS OBrien, your post is wrong on so many counts, I don’t know where to start. The amount of arable land on the globe is tremendous and more than is currently needed to feed the world. The US government still pays farmers not to grow crops in order to keep prices stable. Patterns of precipitation change over time, as you say, and there is nothing we can do about it. Plain and simply, people, we cannot contol the weather. The idea that we can is the greatest practical joke in history. Let me say it again – we cannot control the weather.
    4. Jim, what is terrifying? Global warming is terrifying? Puh-leeze. If you’re terrified, you need to get a life.

    Have a nice day!

  17. longhorngopher –

    You seem to be confusing a number of issues, so let’s address them one at a time.

    The fact is that the earth has been warmer, far warmer, in the past than it is now, and, as far as I can tell, the planet wasn’t destroyed.

    This is true. However, humanity wasn’t a dominant species with a population of 6+ billion the last time the earth was this hot. We didn’t have hundreds of millions of people in low-lying coastal cities that might be flooded directly by sea level rise or indirectly by storms. We didn’t have entire nations that could be flooded – affected populations simply picked up and moved, and likely fought wars with clubs, knives, spears, and bow and arrow. Before, the magnitude of losses was tiny, both in terms of percentage of human population and in total number of people. This time around, if climate-driven war does occur, the losses could be massive, both as a percentage of human population and in total numbers.

    So global heating won’t destroy the planet. Even if it results in a mass extinction, it won’t destroy all life on the planet either. But it might be responsible for creating the conditions where humanity destroys a significant percentage of itself.

    [E]ven if the earth is undergoing a dramatic climate change, how do we really know that that is a bad thing?

    This depends on what you mean by “bad.” Based on prior mass extinctions where a changing climate played a part (which is at least two of them – see the second section of this Carboholic), if you define “causing the extinction of 50% of more of all life on earth” as bad, then global heating is a “bad thing.” If you consider the possible conflicts over energy, food, fresh water, and arable land that I described just above as a problem, then global heating qualifies a “bad thing.” If you enjoy a high standard of living and don’t want it to be dragged down by climate refugees, resource conflicts, desertification of farmland, and the shifting of optimal growing regions further toward the poles, then global heating still qualifies as a “bad thing.”

    Science, to put it in small terms that you can understand, is about being able to actually prove a theory by replicating results in a closed environment.

    Incorrect. The scientific method is as follows:

    observe
    formulate hypothesis to explain observations
    test hypothesis
    observe results
    formulate new hypothesis based on new observations
    repeat steps 3-6

    Note that the scientific method doesn’t say anything about needing a “closed environment” in order to test – closed environments are useful in science because they reduce errors, not because they’re required. In fact, some science is impossible to perform in a closed environment, yet that doesn’t make it any less scientific. For example, it’s not possible to prove plate tectonics in a closed environment, yet plate tectonics underlies nearly everything that’s known about geology today and it has been verified repeatedly since it was initially proposed. For a more detailed discussion on the scientific method than I could possibly perform here, Wikipedia has a decent article on the subject with a very good list of notes, references, and links at the bottom.

    Global warming theory is simply theory.

    Incorrect on a couple of different levels. First, that the planet has heated up since 1880 is scientific fact – we have directly measured data that shows it, as the GISSTEMP images above illustrate. Anthropogenic global heating (the idea that human beings are the cause of the observed heating), however, is a scientific theory. A scientific theory, as defined by the Encyclopedia Brittanica, is a “systematic ideational structure of broad scope, conceived by the human imagination, that encompasses a family of empirical (experiential) laws regarding regularities existing in objects and events, both observed and posited. A scientific theory is a structure suggested by these laws and is devised to explain them in a scientifically rational manner.” In simpler terms, a scientific theory is a hypothesis that has been tested, refined, retested, re-refined, etc. almost innumerable times and found to be an accurate representation of the data. Some other examples of scientific theories are plate tectonics, evolution, the Big Bang theory, and both chaos and complexity theory.

    The sense that you’re using the word “theory” is that of definition 6.b at Mirriam Webster, namely “an unproved assumption : conjecture”. Please stop conflating the two uses of the word, as they are most definitely not the same.

    Scientists cannot prove the cause(s) (they have ideas, theories, but no proof), cannot replicate results, and cannot predict the effects.

    Your use of the words “prove” and “proof” suggest a lack of understanding of how science works.

    Science never “proves” something in the mathematical, A=B sense. There is always uncertainty due to errors and biases in data collection and to untestable axioms and assumptions that must be used as starting points. However, in the sense that the probability of being wrong can be calculated in a statistical sense as being vanishingly small due to the large number of tests conducted, review and verification of results by qualified peers, etc., scientists can be certain beyond a reasonable doubt of the accuracy of their scientific theories and laws, just not beyond all doubt.

    As for replication of results, this is not true. Because of the lack of a closed system on which to perform experiments (creating an actual alternate Earth isn’t feasible), Scientists have developed computer climate models that enable them to run virtual experiments. Because the scientists know that their models aren’t perfect, they run lots of different tests to determine the sensitivity of the outcome to small changes in model parameters. This is called a sensitivity analysis, and the variability in the output enables a statistical analysis of the quality of the model. A recent paper analyzed the quality of the latest generation of climate models and found them statistically equal to a re-analysis of measured climate data.

    One of the other things that scientists who rely on modeling have to do is verify that the outputs of the results are correct. In a model of something like climate, where we have to wait decades or centuries to have solid data, scientists use a modeling technique called a Monte Carlo method. While Wikipedia can give you a decent overview of how it works, the gist is that it relies on random variations in input parameters to produce different outputs, and then the statistical properties (mean, median, and standard deviation) of the outputs are used to make predictions. Because we cannot know all of the inputs to a climate model, and because climate models are attempting to model a highly dynamic system, the use of a statistical process provides some level of rigor to the science.

    In the case of the most recent generation of climate models, they all agree that a) the Earth is heating up and b) that human activity is the primary driver of it. This result has been replicated innumerable times and statistically validated. The standard deviation (a statistical measurement of error) of the model is much smaller than the predicted global heating over the next 92 years.

    Finally, the predictions of the models are being validated, and I report on those validations all the time in the Weekly Carboholic. The jet streams were predicted by the models to move further toward the poles and away from the equator as a result of global heating – they have done so. The upper troposphere was predicted to heat up, and a recent paper shows that it actually has, contrary to prior data that had so much statistical deviation that it was scientifically useless (not that this fact stopped global heating skeptics from trumpeting the results as proof that the models were bad). Climate models predicted that ocean temperature would rise faster than it apparently did, but a recent paper revealed a measurement device construction error that created a systematic bias in the data that pushed ocean temperatures down artificially – the corrected data matches up with the climate models.

    Meteorologists cannot accurately predict today’s high temperature; how in the hell do you think they can project temperatures 50 years from now?

    Meteorology and climatology are both branches of atmospheric science, but you are implying that meteorology is equivalent to climatology – it is not. The science of meteorology concerns itself with understanding how the broader climate produces local weather and attempts to predict, over short time scales, local weather. Climate is fundamentally the weather averaged over a large region and over years or decades, and it’s this average that climatology studies. Climatology does not try to predict the weather, only the average weather a region is likely to have over the course of years or decades. Saying that the desert southwest will be even hotter and dryer in 10 years than it is today, or that hotter temperatures will lead to greater evaporation, higher concentrations of water vapor, and thus likely higher intensity storms and more flooding is something that speaks to the climate, but says very little about the weather.

    The amount of arable land on the globe is tremendous and more than is currently needed to feed the world.

    True. However, soil is a finite resource, so it may not necessarily stay this way even without desertification and a poleward shift of growing regions. In addition, the surface area of a sphere within latitude bands gets smaller as you exit the equator, so the geometry of the earth, combined with its geology, may well produce smaller areas of arable land. Finally, human beings aren’t the only things that require that land to survive. I’m quite comfortable with valuing human life over that of animals, but even I still like seeing wild animals and plants and unspoiled wilderness to fish and hike in. There may well be less of that, or less of it of certain types (boreal forest, for example) as a result of global heating.

    Plain and simply, people, we cannot control the weather.

    Again, there’s a big difference between climate and weather. Just because we cannot control weather doesn’t mean we cannot influence it (we can – cloud seeding works on some scales). Similarly, we can influence climate. Humanity does so all the time – atmospheric contrails cool the planet, the ozone hole over Antarctica created by man-made CFCs is suspected as having artificially cooled that continent, and deforestation of the Amazon has already changed precipitation patterns throughout the Amazon basin.

    In other words, while we can’t control the weather, we can influence it to make more or less to our liking. The same is true of the global climate.

    All that said, I’d like to address something that what you said in your initial post:

    [F]armers in the Midwest USA are seeing some of the highest crop yields in history.

    You’re stating that higher carbon dioxide (CO2) concentrations are good for crops, and that it’s the higher CO2 that’s responsible for for the higher yields. This is simultaneously true and false – more CO2 does mean greater yields, but higher yields don’t necessarily mean higher yield with equivalently high nutritional value. In fact, a number of studies have shown the opposite for a number of crops. In addition, if you look at this report from the Pew Center on Global Climate Change, you find that the effects of global heating on agriculture is not at all as settled as you believe.

    I agree with you that global heating shouldn’t be terrifying. However, it should be of concern. A complete lack of concern illustrates either ignorance or denial, although this comment should have dispelled some of the ignorance.

  18. Brian, I appreciate the fact that you took the time to respond in such detail to my post. I completely disagree with your characterization of my lack of concern as denial or ignorance. I have a wife; I have three children; I have a more than full-time job and numerous outside activities. Global warming is not something that occupies my time because, first, I think the “predictions” are ridiculous (that’s really what I meant by “global warming theory” – the predictions of seas rising 20 feet, 50% of the population being destroyed? – what are you smoking?) and, second, it’s low on my priority list. Neither of these things has anything to do with ignorance or denial. Personally, I think if you take some of dire warnings seriously, then you are ignorant.

    That being said, I’m a staunch believer in conservation. We recycle everything we can, use CF light bulbs, have a highly-energy efficient home (keep our thermostats up in the summer and down in the winter, much to the chagrin of our children), and use ethanol blend fuels when possible. I do have to drive a great deal for my job, but we have planted numerous plants and trees around our yard to help offset that.

  19. Gopher: Brian laid out a simply overwhelmingly scientific case. Your response? “What are you smoking?”

    I don’t doubt that you love your family and I’m glad you use CF bulbs. But your contributions here, in toto, amount to little more than “mama said Jesus loves me.”

  20. There are a number of possible responses to those Monckton pieces. The first is that the second link is a false meme.

    From the APS website

    The American Physical Society reaffirms the following position on climate change, adopted by its governing body, the APS Council, on November 18, 2007:

    “Emissions of greenhouse gases from human activities are changing the atmosphere in ways that affect the Earth’s climate.”

    An article at odds with this statement recently appeared in an online newsletter of the APS Forum on Physics and Society, one of 39 units of APS. The header of this newsletter carries the statement that “Opinions expressed are those of the authors alone and do not necessarily reflect the views of the APS or of the Forum.” This newsletter is not a journal of the APS and it is not peer reviewed. (emphasis added)

    In other words, the newsletter editor’s statements are not the official APS position, this policy statement is.

    As far as Monckton’s science goes, that requires a detailed debunking outside the scope of a comment. Not only have others pointed out that he’s making a bunch of fundamental math errors and unsupported assumptions and double-counting his climate sensitivity reductions, but he’s used 7 years of a trendline without pointing out that a) the r2 statistical value of accuracy indicates that anything less than about 15 years is statistically meaningless for trends and b) the trend is so short that the 95% confidence error on his trendline is about 3x the trend itself. In other words, he’s either misunderstanding or misrepresenting his data.

  21. Notice they don’t publish the temperatures from before 1880? That’s because if they do, it will show that global warming is minimal over long term. The GISS removed that information from their website so it looks like there is a dramatic increase in temperature. Read Michael Crichton’s book State of Fear, he has a very good bibliography in the back regarding the subject.

  22. Sorry, wildfire, but you’re wrong. The data doesn’t go before 1880 because that’s as far back as direct measurements of temperature on a significant percentage of the planet go. As I pointed out in “Changes in U.S. climate data do nothing to debunk global heating”, direct temperature measurements go back to 1785 in India, 1788 in Australia, 1872 in Japan, and 1765 in France. The US data starts in 1880 because it’s related to the number and geographic coverage of surface temperature measurement stations, just like the RSS/UAH satellite data starts in 1979 because that’s when the MSU satellites were first launched. HadCRUT data also starts in 1880 because that’s when the British had wide enough coverage of land stations to start having a chance of estimating global temperature.

    Before 1880 scientists have to use proxies instead of direct measurements, and the GISS et al measurements aren’t proxy-based.