Is Earth warming up or not?

But the Earth is warming up, you say.  Well, the evidence for that is very skimpy and is, due to the poor quality of surface temperature recordings, not supported by an overwhelming quantity and quality of facts.  Moreover, what we can consider to be normal at any given time depends on the time interval into which a given point in time falls. 

The climate alarmists do not tell us that for the years following the "high" temperatures reached in 1998 the global average annual temperatures reached were in every single year below the "high" reached in 1998 and appear to have begun a downward trend.

Many surface temperature measurements that are being tracked and reported are being taken and recorded in or near large urban centres.  It would be no more accurate to extrapolate from them to the rest of the World than it would be to extrapolate from the reading in my kitchen right now and to conclude that we really and truly don't have now [in 2003] the coldest spring we've had for the last 150 years, ever since temperatures were recorded more or less on a global basis.

And that is where the problem lies.  We don't have a sufficiently accurate record of surface-air-temperature readings to tell us what our climate has been in this region, or in North America, or for that matter in the whole World, to tell us what normal is.  What we know is that "normal" is the average of a whole range of values.  What we don't know is what the whole range of values is and how far away from or how close to normal we are right now, or do we?

Whatever the length of the interval, whether it covers the last 12 thousand, 450 thousand, 5 million, 65 million or 500 million years, global average temperatures have been falling steadily.  The annual global average temperatures are now considerably lower than they were many times in the past. 

The rising global temperature trend that excites the climate alarmists covers only the last 100 years or so since we came out of the Little Ice Age.  Most of the warming that occurred during that interval occurred during the first 44 years of the last century, prior to the explosive, post-war growth of industry, traffic and transportation.  The global temperature saw a decline during the following years and reached the "high" temperatures experienced in 1944 not again until 1981.  The "alarming" warming that gets the climate alarmists' knickers into knots happened during the interval from the mid-1940s to 1998, even though in the longer temperature trend that warming trend is only a mere, almost-imperceptible blip and means nothing other than that global temperatures were many times in the recent and not-so-recent past considerably higher.

Systematic surface-air-temperature recordings were not taken everywhere or universally for more than about 150 years, and even at that, not even in the whole world, only in some portions of it.⁴  No doubt, as the Fraser Institute's Guide to the Science of Global Warming identifies, "The historical surface and proxy records suggest that temperatures rose about 0.5°C in the early twentieth century—before most of the greenhouse gases were added to the air by human activities."⁵  It must be stressed that the global temperatures didn't increase after the explosive growth of industry following W.W. II.

There are ways to infer from other evidence what the climatological record was, going back for quite a long time, thousands of years.⁶  

A surface temperature record, containing recordings from many weather stations around the world (the vast majority of them no longer operating, such as many in the Canadian Arctic), is available at the website of the Goddard Institute for Space Sciences.⁷

Source: GISS

Consider also the explanation offered by the Goddard Institute for Space Studies following that graph:

Global Surface Air Temperature is based on surface air measurements at meteorological stations. Click for temperature maps and more detailed data. Since corresponding data are unavailable over the ocean, surface air temperature anomalies are combined with ocean temperature anomalies to obtain a 'Land-Ocean Temperature Index'.

 

That is not the only problem afflicting the data reflected in the graph.   A major issue of concern is that the total number of land-based weather stations declined over time.  Not only that, but an increasingly disproportionate number of the weather stations remaining in operation are located in urban and not in rural areas.  The following graph shows an example of what these differences are.

Keep in mind that although these differences are well known and corrections have ostensibly been made to take them into account, the GISS data base used in the calculations of global warming trends nevertheless contains them.  The results of the calculation of regional and global averages are therefore tainted by the presence of the bias introduced through the heat-island effect.

However, consider also that even though airports are in the open, they do have large areas of paved runways that store day-time heat which they release slowly during the night.  I don't know where the temperature gauges for the Edmonton International Airport are located in relation to the runways, but the airport buildings are at the SE end of the expanse of the runways.

The calculations done by General Circulation Models (GCMs) are the main source of the information that fuels the global warming hysteria.  Nevertheless, not one of them comes acceptably close to accurately calculating what the climate presently is at any location, let alone of the whole Earth.  Not only that, but all of the GCMs differ widely from one another as to what the climate was in the past, and as to what it is supposed to be in the future.

Therein lies the problem.  No one in his right mind will base any decisions about the future on tools that cannot determine with acceptable accuracy what the present is and the past was.

• Reality check: UAH (University of Alabama in Huntsville) monthly globally averaged lower atmospheric temperature variations since 1979 as measured by NOAA and NASA satellites.

Update 2009 12 11:

The GISS temperature record can no longer be trusted. 

On or around about Nov. 14, 2009, GISS began to use a new global temperature data set that deleted temperature records relating to the late 19th and early 20th centuries.  Not only that, but the temperature data that remained in use were adjusted downward for dates preceding the year 2000 (increasingly downward the farther back in the temperature record they go), thereby creating or exaggerating "warming" trends for individual locations.

A discussion thread at http://wattsupwiththat.com details the nature of the data fiddling.

From that discussion thread:

...See under “What’s New”:
http://data.giss.nasa.gov/gistemp/graphs/

“Nov. 14, 2009: USHCN_V2 is now used rather than the older version 1. The only visible effect is a slight increase of the US trend after year 2000 due to the fact that NOAA extended the TOBS and other adjustment to those years.
Sep. 11, 2009: NOAA NCDC provided an updated file on Sept. 9 of the GHCN data used in our analysis. The new file has increased data quality checks in the tropics. Beginning Sept. 11 the GISS analysis uses the new NOAA data set. ”

The "visible effect" of the new, manipulated data set is far greater than the quoted note implies.  The data changes were without a doubt manufactured to create a warming trend where none exists or to exaggerate possibly existing warming trends.

This is not the first time that the gate keepers of climate data were caught in the act of large-scale falsifying of existing data.

Temperatures at our farm (the thermometer probe is located at the north side of the house, about 2.40 m above ground and about 0.75m away from the house) are on average about 3°C lower than the readings taken at the Edmonton International Airport.  Our house is located about 70 miles to the NE of the airport.  Here is an illustration of the differences between temperatures reported at some locations in the Edmonton area.

If temperature readings taken in a technologically advanced nation are unlikely to be accurate and instead probably fictitious or at best interpolated with a dubious degree of accuracy, what conclusions is one to draw for readings taken in underdeveloped nations?

For a discussion of the problems faced in determining correct assessments of surface temperatures and their averages even for individual locations, refer to the following:

Surface Temperature Analysis
The Elusive Absolute Surface Air Temperature (SAT),

By GISS

Aside from the design- and human errors that may and do creep in when setting up instrumentation and taking readings, the readings are affected by the heat island effect generated in urban areas.  The heat-island effect is substantial, measurable in communities of 250 or more residents, increasing over time as energy consumption and population density increase, and cannot be ignored.  Determining accurate correction factors for individual areas in which temperature readings are taken in uncharacteristic hot-spots becomes difficult and even impossible if no corresponding records of readings exist for the surrounding rural areas, and as more and more weather stations in rural areas are being taken out of service.

However, for a number of years now, temperature measurements have been made via balloons and, in an even more thorough and comprehensive fashion, via satellites.  The records established by those means show no or at worst only almost imperceptible global warming.  Of course, those records are unbiased by human error and undistorted by the fact that temperature readings taken in urban areas are affected by the heat-island effects of the cities in which many are taken and that taint the results of global averaging of global temperature records.

Measuring the Temperature of Earth From Space

Even with Needed Corrections, Data Still Don't Show the Expected Signature of Global Warming

By Dr. Roy Spencer 
Senior Scientist for Climate Studies 
NASA/Marshall Space Flight Center 

14 August 1998 

Full Story

Source: NASA

Source: NASA

It does not matter where you click on the global map or for which area you have the tool average the values, there is no indication anywhere that shows a global warming calamity!

Still, even though balloon and satellite records agree with one another, the surface record disagrees to some extent with both of them.  Why is that?  Dr. Hoyt explains:

Of the 2907 stations in the [GISS] database, only 161 (or 5.5%) have complete temporal coverage from 1900 to 1990. All but 19 of these stations are in the United States. The US, with the most complete record anywhere, has no trend in temperatures during this century [that is, the temperature trend is neither increasing nor decreasing with time —WHS]. In 1989 and 1990 about 30% of the stations ceased reporting. This may account for the difference in global temperature trends derived from surface observations when compared to balloon and satellite observations.  Support for this idea comes from the fact that 135 stations in the USSR ceased observing at the end of 1989. Subsequently there appeared to be a warming in the USSR but this warming is not supported by pressure observations. Thus, it appears half or more of the reported global warming from ground observations is arising from this change in station coverage. It is possible that as much as 0.2 C of the 0.25 C warming for 1979-1999 can be explained by this change in stations, although more study is required to refine this number. Other locations where the surface network has notable problems include South Africa, Nigeria, Timbuktu, Algeria, Peru, central and coastal Brazil, the Seychelles, Diego Garcia, New Guinea, and several Polynesian islands.

— Greenhouse Warming: Fact, Hypothesis, or Myth?
by Douglas V. Hoyt, [email protected]
March 24, 2001)

Douglas Hoyt further identifies in his discussion paper that "The so-called "global" measurements are not really global at all. At best, they once sampled 40% of the globe."  That was more than 40 years ago.  Now the area covered by surface temperature measurements comprises only about 20 percent or less of the global surface.

The Temporal Variations in Areal Coverage

Source: Douglas Hoyt

Douglas Hoyt discusses the implications of that in his paper.  He states that "it is important to realize that only 8% of the climate variability can be categorized as global with the remaining 92% being regional variations." 

It is normal practice to do sampling of less than a complete number of data measuring points in space and or time.  Although it is possible to draw accurate conclusions with a reasonable degree of confidence from such a small sample to the universe it represents, that is possible only if the sample was randomly selected.  The sample of data collection points available and used by any agency in determining trends for surface measurements is predetermined and not randomly selected, it is unevenly distributed over the globe (with very large concentrations in some areas and extremely low concentrations or even total absence in others) and can therefore not be considered to be a representative sample that permits to make valid conclusions for average global temperature trends.
   Furthermore, there are: the designed instrument error (+/-1°C in many of Canada's weather stations); the errors in placement of instruments and the human errors in taking readings.  In combination, those errors alone exceed by far any claims of the extent of temperatures record trends that are said to have been measured or calculated to be in the order of a 0.5°C increase during the past century.
   Within the range of possible values that could all be true, why pick an increase of 0.5°C during the past century and insist that it is evidence of global warming when two other, far more accurate and very comprehensive methods of measuring show no warming trend at all?
    Would it not be far more important to adjust the accuracy of surface measurements to the standards sets by balloon and satellite measurements, rather than to ignore the results of the latter two methods of measuring global temperature trends?   Why insist that a seriously flawed method of measuring surface temperatures that furthermore still only identifies a trivial amount of warming shall be the justification for trillions of dollars in expenditures to do the impossible and unnecessary: attempt to curb and control global warming?

John L. Daly, science advisor for the Greening Earth Society, discussed all of those issues and more in much greater and convincing detail in his essay,

The Surface Record: Global Mean Temperature and How it is Determined at Surface Level  (June 2000)   An argument for an independent review of the `surface record'. The satellites were reviewed, so why has the `surface record' escaped independent examination?

Gallery of Temperature Change Data (off-site)

This is the most comprehensive compendium of temperature graphs I have seen.  It quite nicely illustrates that the only constant of climate change is constant change.  The graphs cover records and reconstructions of temperatures covering intervals ranging from 1980 - 2007 to 542 million years before the present to now.  The gallery shows ten graphs in all.

And, yes, there were times during the past 542 million years when it was much hotter than it is now, but there were also times when it was much colder.  It is unavoidable to conclude that we will almost certainly soon have another interval when it will be much colder than it presently is.  In fact, the current levelling-off of the global average annual temperature trend (something that no self-respecting climate alarmist dares to tell the public about) could well signify the beginning of that cold period to come.

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