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IN the very first report from the United Nation’s Intergovernmental Panel on Climate Change (IPCC) the Medieval Warm Period was evident as a period, about as warm as the present, occurring from AD 950 to 1250. In subsequent IPCC reports there is no such warm period in this historical record. Instead there is a graph, shaped like an ice-hockey stick, which suggests temperatures were flat until the 20th Century, when sudden and sustained warming occurs.

The change, from the presence of a clear warm period about 1000 years ago to none at all in more recent reports, is justified by the IPCC on the basis that while it may have been warmer in Europe when the Vikings founded settlements on Greenland, and England was exporting wine to France, this warming was not global. The warming, according to the IPCC, was restricted to the North Atlantic region. Which begs the question, how important is regional variability when we are discussing global warming?

Furthermore, no-one lives in a world climate. It’s what happens locally and regionally that is most important to individual communities. We should expect that an El Nino event in the Pacific Ocean, for example, is going to affect the western United States very differently from eastern Australia. Indeed, such events are often associated with wetter conditions in southwest USA, and hotter, drier conditions in eastern Australia.

The focus on mean global temperatures, rather than regional variability, has been a consequence of the politicization of climate science and the desire to use the authority of science to force political change. Many of those opposed to this political agenda, often labelled sceptics or deniers, have focused on temperature series that show little or no global warming, while the mainstream climate science community has gone to ever more extreme lengths to make particular temperature time series conform to their theory of anthropogenic global warming.

Some so-called sceptics had been focusing on the satellite record over recent years, because that component of this record based on the mean global temperature, showed no increase since the El Nino event of 1997/98, Chart 1a. However, more recently, and largely as a consequence of the relatively warm and wet winter in the northern hemisphere, there has been another spike in the global mean temperature based on this satellite record.

This signifies the end of “the pause” in the mean global temperature for the UAH satellite record. Though, interestingly, some have simply changed their geographic focus, much as the IPCC did with the Medieval Warm Period.  In particular, some so-called sceptics now emphasis the geographic variability in the satellite record, in particular, that southern hemisphere temperatures showing no recent spike.

The satellite record as compiled by scientists John Christy and Roy Spencer, at the University of Alabama (UAH), Huntsville, includes monthly updates for the entire globe, for the northern and southern hemispheres, the south and north poles, the tropics, the United States of America, and also for Australia. The UAH satellite record also separates out ‘land’ and ‘ocean’. So, for the northern hemisphere, as an example, it is possible to understand temperature trends for the land versus ocean components of this record. When we consider the land component of the UAH satellite record for the northern hemisphere, the recent spike in temperatures is particularly pronounced, Chart 1b. Meanwhile, for Australia, there is no such recent spike in temperatures. Rather temperatures appear to cycle within an approximate 4 degree Celsius band, Chart 1c.

Patterns in the historical temperature record, and geographic variability in temperature trends, potentially gives us insight into the drivers of climate change. Many, however, would argue that as the satellite temperature record only goes back 38 years to 1978, that this is too short a period for discerning correlations with sunspots, and other extraterrestrial phenomena. In fact, consistency between the UAH satellite record for Australia, and records from individual weather station in Australia over this same period (December 1978 – March 2016), potentially gives us the opportunity to infer what temperatures would have been like at least back to when these weather stations were first installed. There is, for example, a reliable thermometer temperature record for Richmond in north eastern Australia back to 1893. Considering just the trends, not the absolute temperatures, the thermometer record for this location shows a remarkably good correlation with the satellite record for all of Australia for the period December 1978 to March 2016, Chart 2.

The much longer unadjusted historical temperature record for Richmond also shows significant intra-annual variability but broadly with a cooling trend to 1950, following by warming to the present. The hottest year in the entire record for Richmond, consistent with many locations in eastern Australia, is 1915.

The pattern in the unadjusted thermometer record for Richmond, and the shorter satellite records for all of Australia, the northern hemisphere and the globe, are not consistent with carbon dioxide as a significant driver of temperature change.

Additional Information: 

For more information on the UAH satellite record compared with other global data bases consider reading a recent post by Bob Tisdale at WUWT: https://wattsupwiththat.com/2016/03/12/february-2016-global-surface-landocean-and-lower-troposphere-temperature-anomaly-update/

For more information on the temperature record for Richmond, and why this unadjusted series is so unique and important consider reading a recent post focused on Darwin, but also considering other sites in northern Australia, here:  https://jennifermarohasy.com.dev.internet-thinking.com.au/2016/02/12910/

I have commented in more detail on the ‘end of the pause’ and the likely reason for the recent surge in the global mean temperature, as measured by satellites, in a recent popular article at On Line Opinion here: http://www.onlineopinion.com.au/view.asp?article=18111

I was invited to speak at the Liberal Democrats Conference in Sydney last Sunday.   I began by explaining that while the delegates may have though homogenization was a term used exclusively for milk, that homogenization is also a technical term used in climate science, but with an altogether different meaning. It allows scientists to remodel historical temperature data so it’s closer to the heart’s desire.

These few words – closer to the heart’s desire – have been borrowed from that famous poem the Rubaiyat of Omar Khayyam. The stanza reads:

Ah, Love! could thou and I with Fate conspire
To grasp this sorry Scheme of Things entire!
Would not we shatter it to bits-and then
Re-mould it nearer to the Heart’s Desire!

Omar used the word “remould”, climate scientists say they are improving the data.

The end result is the same: something has been changed.

The scientific revolution rejected unnatural causes to explain natural phenomena, rejected appeals to authority, and rejected revelation, in favor of empirical evidence. Today, the biggest threat to science is from the sophisticated remodeling of data, known in climate science as homogenization.

An analogy can be made between the remodeling of scientific data, which is now common in a variety of disciplines from conservation biology to climate science, and “fitting up” people the police know to be guilty, but for whom they can’t muster enough forensic evidence for a conviction. This is also a form of “noble cause corruption”.

Why is it a form of corruption? Because we expect the criminal justice system to be fair, to be based on legitimate evidence. Science should also be about facts, and evidence.

Let’s consider a real world example of homogenization, specifically the maximum temperature record for Darwin.

There are very few continuous, surface temperature recording from northern Australia that extend beyond 60 years. The Australian Bureau of Meteorology, Hadley Centre (UK Met Office), Goddard Institute for Space Studies (NASA GISS), and other institutions concerned with the calculation of global temperature trends, join temperatures recorded at the Darwin post office from 1882 until January 1942 with temperatures from the Darwin airport recorded from February 1941 to the present, and then make adjustments. There is no temperature record at the post office after 1942 because the Darwin post office was bombed in Japanese air raids.

Temperatures were recorded at the Darwin post office from 1882, but are only shown in Figure 1 from 1895, which is the first full year of recordings in a Stevenson screen.

In the above chart I’m only showing the temperatures from 1895, even though they were measured from 1882, because I’ve excluded the early years when measurements were not recorded in a Stevenson screen. So, I’m only showing temperatures recorded from recognized official standard equipment.

The temperatures as recorded from the mercury thermometer in a Stevenson screen at the post office from 1895 to 1942 show statistically significant cooling of almost 2 degrees Celsius per century.

This clearly does not accord with the theory of anthropogenic global warming. And indeed these raw observational values are not incorporated into official temperature time series used to calculate national and global temperature trends. First the data is homogenized.

In particular, the Bureau of Meteorology truncate the record so it starts in 1910, rather than 1895. Then they drop down the temperatures as recorded at the post office by -0.18 degree for all values before February 1941, and by a massive -1.12 for all values before January 1937. This has the effect of creating a warming trend, as shown by the red line in the following chart, Figure 2.

The homogenized series for Darwin, which is incorporated into official data sets, shows warming of 1.3 degree Celsius, which accord much better with global warming theory.

Is this drop-down justified? Let’s consider some other series from northern Australia.

There are very few long continuous temperature records for northern Australia. The records for Broome, Derby, Wyndham and Halls Creek in Western Australia, and for Richmond, Burketown and Palmerville in Queensland are the only continuous high quality series that extend from 1898 to at least 1941. This includes the period of the adjustments to the Darwin post office data. These towns are marked in red on the map of northern Australia, Figure 3.

To be clear, I have compared Darwin post office against the series for these locations because they were recorded at the same site, in proper equipment (mercury thermometer in a Stevenson screen), and the individual series do not show any discontinuities when appropriate statistical tests are applied.

Considering the series from Western Australia, Figure 4, it is apparent that there is much inter-annual variation. This is typical of observational temperature data from around the world. While annual temperatures fluctuate from year to year, it is apparent that there is considerable synchrony between locations. Indeed, there are synchronous peaks in 1900, 1906, 1915, 1928, 1932 and 1936. Note that temperatures at Wyndham, Derby and Halls Creek all dip together in 1939, while temperature at Darwin decline from 1936, Figure 4.

Temperatures at Darwin are less synchronous with temperatures from northern Queensland, Figure 5. In particular the peaks in the Darwin temperature series appear to lag the Queensland series.

There is considerably synchrony between the Queensland locations with Burketown, Palmerville and Richmond all showing spikes in 1915. Of course this was an El Nino drought year, and the year that the Murray River ran dry in south eastern Australia. Interestingly the Queensland series all show a significant drop-down from 1939, Figure 5.

None of the temperature series, either from Western Australia or Queensand, show the expected global warming from 1898 to 1941.

Only one of these northern locations has a continuous temperature record from 1898 to the present, that location is Richmond in Queensland. The maximum temperature series for Richmond, which is shown by the green line in Figure 6, doesn’t actually look anything like the homogenized series for Darwin, which is shown by the red line.

The series for Richmond, which represents temperatures for the one location recorded by a mercury thermometer in a Stevenson screen, is actually remarkably similar to the un-homogenized series for Darwin, Figure 7.

What I’ve discovered, after looking at hundreds of such raw time series from eastern Australia, is that they tend to follow a similar pattern: there is almost always cooling in the first part of the record and then warming at least from 1960. Yet whenever I look at the homogenized official records for these same locations they all show statistically significant warming from the beginning of the record.

Let’s now consider the Bureau’s justifications for the homogenization of Darwin.

The first thing that the Bureau does to the Darwin temperature series is discard all the data recorded before 1st January 1910 on the basis it might not be reliable. Yet we know that a mercury thermometer in a Stevenson screen was the primary instrument used to record temperatures at the Darwin post office from March 1894, and that there was no site move, or equipment change, for the period to 1910. Yet this valuable 15 whole years of data from 1895 to 1910 are just discarded.

Then the Bureau drop the maximum temperature series down by -0.18 degree Celsius for all data/all recorded observations from February 1941 back to January 1910, and then again by -1.12 degree Celsius for all data before January 1937 back to January 1910. So the adjusted/homogenized series has a statistically significant warming trend of 1.3 degree Celsius per century for the period from 1910 to 2014.

This largest drop-down of -1.12 degree Celsius is justified on the basis that the site became “overshadowed by trees, especially after 1937”. This is what is written in the official catalogue. If shading from trees were the cause of the cooling, then it’s curious that the adjustment is made for the period before the site ‘deteriorated’ because of shading. This is not rational. If the problem occurred from 1937, the correction should be for this period.

Furthermore, photographic evidence from the Northern Territory State Library does not support the hypothesis that the site became progressively more shaded, Figure 8.

In particular, the trees behind the Stevenson screen along the front of the post office building are tallest in the first photograph taken in 1890. In the middle 1930 photograph, the trees immediately in front of the post office appear to have been removed. In the 1940 photograph (third), the trees have apparently regrown in front of the post office and there appears to be some shrubbery where the modified Greenwich thermometer stand was positioned in 1890.

What all of this ignores, is the cyclone that hit Darwin on 10th March 1937. According to the Northern Standard newspaper reporting immediately after the cyclone, “it raged and tore to such vicious purpose that hardly a home or business in Darwin did not suffer some damage… Telephone wires and electric mains were torn down by falling trees and flying sheets of iron, windmills were turned inside out, garden plants and trees were ruined, roads and tracks were obstructed by huge trees…”.

Is it possible that rather than the cooling being due to ‘shading’ from 1937, there was actually less vegetation following the cyclone? In fact, the drop in maximum temperatures is likely to have been due to removal of trees and shrubbery by cyclonic winds. It is more likely that vegetation which had previously screened the post office from the prevailing dry-season south easterlies that have a trajectory over Darwin Harbor, was removed by the cyclone.

While shading can create cooling at a site, a similar effect can be achieved through the removal of wind breaks.
In a study of modifications to orchard climates in New Zealand it has been shown that screening could increase the maximum temperature by 1°C for a 10 meter high shelter.

In conclusion, the homogenization of the record at Darwin is by no means unusual. I used the example of Rutherglen, in north eastern Victoria, in my request late last year to the Auditor-General of Australia for a performance audit of the procedures, and validity of the methodology used by the Bureau of Meteorology.

At Rutherglen a cooling trend of 0.35 degree Celsius per century in the minimum temperature series is homogenized into warming of 1.73 degree Celsius.

In support of this request to the Auditor-General a colleague, Tom Quirk, showed how the raw record for Dubbo in NSW is changing from cooling of 0.16 into warming of 2.42 degree Celsius per century through homogenization. Brisbane in Queensland is changed from cooling of 0.68 to warming of 2.25. Warming at Carnarvon in Western Australia is increased from 0.18 degree per century to 2.02, and so the list goes on.

At an online thread at The Australian newspaper’s website last Monday – following a terrific article by Maurice Newman further supporting my call for an audit of the Bureau of Meteorology – I noticed the following comment:

“Don’t you love the word homogenise? When I was working in the dairy industry we used to have a homogeniser. This was a device for forcing the fat back into the milk. What it did was use a very high pressure to compress and punish the fat until it became part of the milk. No fat was allowed to remain on the top of the milk it all had to be to same consistency… Force the data under pressure to conform to what is required. Torture the data if necessary until it complies…”

Clearly the Bureau uses force to remodel historical temperature data so it’s closer to what they desire.

This is not science. But given the Bureau’s monopoly, and the extent of the political support they received from both Labor and the Coalition, they can effectively do whatever they want.

Western elites are beset by the fear of a coming environmental apocalypse, and climate scientists at the Bureau of Meteorology have undertaken industrial scale homogenization of the historical temperature data to support this phobia.

The late Professor Bob Carter wrote in 2003:

“To the extent that it is possible for any human endeavor to be so, science is value-free. Science is a way of attempting to understand the world in which live from a rational point of view, based on observation, experiment and tested theory.”

“The alternative to a scientific approach”, according to Prof Carter, “is one based on superstition, phobia, religion or politics.”

What the Bureau does to the data from Darwin could even be described as a form of art, based on a mix of desire and phobia. It is not science, and we need to rally against it, against this homogenization.

*****

A PDF version of this presentation with charts can be downloaded here:  https://jennifermarohasy.com.dev.internet-thinking.com.au/wp-content/uploads/2014/08/Marohasy-LibDemNationalConvention-Darwin-Feb2016-VERSIONF.pdf