Global Warming Scam Part 4

2.1.2. UNREPRESENTATIVE SAMPLES
Weather stations are not distributed uniformly and representatively over the earth’s surface. You cannot obtain a plausible average unless you start with a representative sample (see Wunsch et al 2008). Those conducting public opinion polls know very well that their results are meaningless unless they have a sample which covers the whole population in a random and representative fashion. Similarly, the television authorities need to have some way of setting rates for advertisers. Unless they do so the rates will be unfair and they lose money. They go to a lot of trouble in finding a representative sample population upon whose TV sets they can put their set boxes which determine their rates. The whole point of these examples is that their mistakes are soon apparent. Climate “projections” and even “predictions” are always so far ahead that nobody can check on them, so they can never be checked for validity. Weather stations cannot supply a representative sample. They are nearly all near cities or airports and do not include most of the earth’s surface. There are no measurements from farms, pastures, forests, deserts, glaciers, or icecaps. 71% of the earth’s surface is ocean but measurements there are even less representative, with very poor quality control.

2.1.3. NO LOCAL AVERAGE
If you want a “global average anomaly” you must surely start with a “local average anomaly” derived from a local average. No actual measurement of a local average temperature are ever made or at least published. Since temperatures are irregular, it is not even clear what the term “average” may mean. Since there is no sunlight at night, the distribution is skewed, so it cannot be modelled by a symmetrical function. Even if it is possible to find an acceptable mathematical model, there would be several possible alternative “averages”, such as mean, median, geometric, harmonic etc.

At most weather stations there is only one temperature measurement a day. If there is a maximum and minimum thermometer a daily maximum and a daily minimum can be recorded. It seems to be assumed that the mean of these quantities represents some sort of average, but Hansen (2008a) denies its value. Gray (2007a) showed that if you compare this average with the average of the 24 hourly readings from one midnight to another, you get a large bias, which for the average of 24 New Zealand weather stations was +0.5ºC for a typical summer day with a range of +2.6ºC to -0.4ºC and an average of +0.9ºC with a range of +1.9ºC to -0.9ºC for a typical winter day. The positive bias of the max/min average over the mean hourly value can thus be larger than the claimed effects of greenhouse warming. Yet this unsatisfactory “average” is used to derive a “mean global average temperature anomaly.”

Then there is the question of how do they calculate each “anomaly”? The following explanation appears on the NCDC website (2008):
"NOTE: From February 2006 through April 14, 2006, the anomalies provided from the links below were inadvertently provided as departures from the 1961-1990 average. Anomalies are now provided as departures from the 20th century average (1901-2000)."

Now, maybe they were able to calculate an average for the year 2000 from 1,600 stations and 500 gridboxes available and in the year 1901 they had 1,600 stations and 300 gridboxes. It sounds comparable; but the world was a very different place in the year1901 from the year 2000. The total number of possible 5ºx5º gridboxes is 2592, so, even today, they only cover 20% of the earth, and mostly near cities. It was actually better in the year 1985 when there were 6000 stations and nearly 900 gridboxes. Many have been closed down since then, mostly in rural areas where the results are less contaminated by urban heating.

In the year 1901, Antarctica, Central Africa and South America, and most of Siberia had no weather stations. Figures for the oceans were minimal and most of the stations were in the Northern Hemisphere. It might be mentioned that there have never been readings near the North Pole because the Arctic is an ocean. yet they keep telling us it is getting warmer without supporting observations. In 1901 thermometers were graduated in intervals of one degree Fahrenheit and the standards of the equipment, shelters and supervision were very different from today.