There is no quality control on meteorological stations. Nobody knows how many sites are close to towns, buildings, central heating pipes; what instruments are used, who measures, how often.
Some years ago the Australians published pictures of their weather stations. They were withdrawn hurriedly as most could be seen to be subject to bias.. They have re-emerged recently with a new set of photos (BOM 2008), all of which look satisfactory, although the Melbourne station, in a busy city intersection, still seems to be used. Detailed information about the location of weather stations is not readily available. A recent “Google” search for photographs of weather stations provided very few outside the USA or Canada and very few appeared to be free from urban effects, or were from official sources. An exception was the Oklahoma Climatological Survey, which gave a wide range of pictures of its sites, from each compass direction. They supplied a paper (Martinez et al. 2007) which lists all the information they record regularly for each site. It should be obvious that this information cannot be obtained from a remote office and it cannot be extrapolated into the past. There seems to be an improvement taking place as a result of the publicity that is being given to unsuitable stations such as those by Davey et al. (2005) and Pielke et al. (2007) who showed that many of the US Global Historic Climatology Network (GHCN) are unsuitable. Perhaps these improvements are partially responsible for the fact that the surface and satellite records now show a measure of agreement, and both show no recent warming.
2.1.8. CORRECTION OF UNCERTAINTIES
The principles which have guided the correction of the Hadley climate data are given in Brohan et al. (2006). They say under "Uncertainties": "A definitive assessment of uncertainties is impossible because it is always possible that some unknown error has contaminated the data and no quantitative allowance can be made for such unknowns. There are, however, several known limitations in the data and estimates of the likely effects of these limitations can be made” (Defense secretary Rumsfeld, press conference June 6, 2002, London) It is touching that the famous poem of Donald Rumsfeld is now inspiring climate scientists. It is worth quoting.
"THE UNKNOWN
As we know
There are known knowns
There are the things we know we know
We also know
There are known unknowns
That is to say
We know there are some things
We do not know
But there are also unknown unknowns
The ones we don't know
We don't know".
Runnalls and Oke (2006) showed that the recorded temperature in meteorological stations can be influenced by "changes in vegetation, development (buildings, paving), irrigation, cropping and even the maintenance of the site and its instruments".
2.1.10. SEA SURFACE TEMPERATURE
An average global temperature anomaly needs to include the 71% of the earth’s surface that is ocean. There are many temperature measurements made from ships, but the quality control is much worse than on the land and even then whole regions have no figures. Folland and Parker (1995) have claimed to have found a way of incorporating the data. One difficulty is that many early measurements were from buckets drawn from the sea and it is sometimes uncertain whether the buckets were metal or wood. During the first World War measurements could not be made on deck. Also some measurements are from a weather station on board, often beneath the funnel.
Both American temperature compilers, the Goddard Institute of Space Studies (GISS) and The Global Historical Climatology Network (GHCN) have never accepted the use of the sea surface measurements for a global average and they have to resort to a whole host of dubious devices to claim that their figures are “global”. They use recent satellite measurements for the ocean (Reynolds et al. 2002) and extrapolate them into the past. It is very suspicious that incorporating the sea surface measurements seems to make little difference.
Although only 29% of the earth’s surface is land, it is remarkable that, the peak number of 5ºx 5º grid-boxes from land-based weather stations was 880 in 1980, which includes 34% of the earth’s surface. This has been achieved because there are many stations on small islands surrounded by ocean where the land temperature is assumed to be typical of the surrounding ocean. Also a proportion of sea surface measurements is from fixed buoys and weather ships. These and the land stations measure above the surface, whereas current sea surface measurements are made from ship’s engine intake, which is below the surface.
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