Climate Change in Context

In my last post I showed some plots of temperature data derived from ice cores at Vostok base in Antarctica, which indicate we are close to the end of the Holocene.

Here are some more plots from the same data so we can put present concerns about warming in some context.  Please remember- temperatures calculated from ice cores have a resolution of from 20 years recently to 40 to 50 years in the mid-Holocene, to 80 to 85 years in the glacial maximum.  Temperatures shown may be regarded as a rough average of conditions over those intervals.  Also note this dataset is for one point on the earth’s surface, not a global average.  Nevertheless it is a very important dataset as it shows polar conditions over a very long period.

Figure 1:  Vostok temperatures relative to 1999 over the last 20,000 years

The previous glacial maximum had temperatures in the Antarctic about 9 degrees colder than now.  This was followed by a strong warming, the Termination of glacial conditions, resulting in 11,000 years of warm conditions, the Holocene.  The Holocene was not uniformly warm but featured fluctuations of up to 2 degrees above and below current temperatures.  I will look at this later, but first I shall take a closer look at the Termination.  

Figure 2:  Vostok temperatures during the Termination

Point A marks the start of the Termination warming.  Temperatures rose from A to B (by about 6.5 degrees in 3,000 years- about 0.2 degrees per 100 years- so not exactly “rapid” warming).  Temperatures then fell about 2 degrees, before rising even more sharply from C to D, the start of the Holocene.  Figure 3 shows temperatures in this final part of the Termination.

Figure 3:  Vostok temperatures in the steepest part of the Termination

Temperatures increased by about 5 degrees over a bit more than 1,100 years.  Yes, the warming rate was indeed steeper- 0.44 degrees per 100 years on average.  However, the temperature rose 1 degree in less than 50 years at the end of this period.

During the Termination, long term temperature rise was gradual, but punctuated by short periods of much more rapid rise.

Now let’s look at temperature change in the Holocene.

Figure 4:  Vostok temperatures 7,000 to 9,000 years ago

Conditions were not uniformly warm, with fluctuations from -1 to +.5C relative to 1999 over hundreds of years.  But there was one episode with a rise of 2.93 degrees in less than 100 years- now that’s rapid warming.

Figure 5:  Vostok temperatures in the last 2,020 years

More recently, temperatures rose 1.94 degrees in 155 years to 1602, and again 2.2 degrees in 44 years to 1809.

You will notice I have shown 3 datapoints showing 21 year mean annual surface air temperatures at Vostok (1970, 1990, and 2010, with zero at 1990).  This is merely for interest- instrumental air temperatures should never be appended to ice core data.  What it does show is that the rate of present temperature change is well within the range of natural variation.

This is also evident when a Greenland ice core series is compared with modern surface air temperatures.

Figure 6:  Greenland (GISP2) temperatures in the last 4,000 years

I have inserted the decadal average of -29.9 C at the GISP borehole from 2001-2010.  Notice how unremarkable that is.

As the fluctuations at GISP and Vostok have been occurring for thousands of years something other than carbon dioxide emissions must be responsible.

So what about carbon dioxide? Data in the next figure is from Dome Fuji, also in Antarctica.

Figure 7:  Insolation, temperature, and CO2 in the last 350,000 years

Notice that at no time in previous interglacials did carbon dioxide concentration exceed 300ppm, (and despite the higher temperatures than now there was no “runaway” warming.)    And as the Carbon Dioxide Information Analysis Centre says

There is a close correlation between Antarctic temperature and atmospheric concentrations of CO₂ (Barnola et al. 1987). The extension of the Vostok CO₂ record shows that the main trends of CO₂ are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO₂ rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO₂ record shows the present-day levels of CO₂ are unprecedented during the past 420 kyr. Pre-industrial Holocene levels (~280 ppmv) are found during all interglacials, with the highest values (~300 ppmv) found approximately 323 kyr BP. When the Vostok ice core data were compared with other ice core data (Delmas et al. 1980; Neftel et al. 1982) for the past 30,000 – 40,000 years, good agreement was found between the records: all show low CO₂ values [~200 parts per million by volume (ppmv)] during the Last Glacial Maximum and increased atmospheric CO₂ concentrations associated with the glacial-Holocene transition. According to Barnola et al. (1991) and Petit et al. (1999) these measurements indicate that, at the beginning of the deglaciations, the CO₂ increase either was in phase or lagged by less than ~1000 years with respect to the Antarctic temperature, whereas it clearly lagged behind the temperature at the onset of the glaciations. (My emphasis).

Therefore, carbon dioxide did not drive, but followed, temperature change in the past; past rapid warming did not lead to positive feedbacks and runaway warming; and the instrumental record is far too short to draw any definitive conclusion about recent warming, which cannot be differentiated from past Antarctic and Greenland temperature fluctuations.

There is no climate crisis.

How Accurate Is Australia’s Temperature Record? Part 1

In my last post I showed that maximum temperature (Tmax) as reported by ACORN-SAT (Australian Climate Observations Reference Network-Surface Air Temperature) appears to be responsible for the growing divergence of the difference between Tmax and tropospheric temperatures from Australia’s rainfall.

In this post I show how Tmax is related to rainfall, and show that while this relationship holds for discrete periods throughout the last 110 years, Tmax has apparently diverged from what we would expect.  In other words, the Acorn Tmax record is faulty and unreliable.

For much of this analysis I am indebted to Dr Bill Johnston who has posted a number of papers at Bomwatch using the relationship between Tmax and rainfall.

At any land based location annual maximum temperature varies with rainfall: wet years are cooler, dry years are warmer.  More rainfall (with accompanying clouds that reflect solar radiation) brings cooler air to the ground; provides more moisture in the air, streams, waterholes, and the soil which cools by evaporation; causes vegetation to grow, the extra vegetation shading the ground and retaining moisture, with transpiration providing further cooling; and in moist conditions deep convective overturning moves vast amounts of water and heat high into the troposphere- especially evident in thunderstorms.  Less rainfall means the opposite: more solar radiation reaches the ground with fewer clouds and less vegetation; there is less moisture available to evaporate; less vegetation growth and transpiration; and much less heat is transferred to the troposphere through convective overturning.

While more rainfall than the landscape can hold results in runoff in rivers and streams, thus removing some moisture from the immediate area, this affects large regions only in tropical coastal catchments- the Kimberleys, the Gulf rivers, the Burdekin and Fitzroy.  Across the bulk of Australia there is very little discharge of water to the oceans.  In the Murray-Darling Basin, on average less than 0.005% of rainfall is discharged from the Murray mouth. (BOM rainfall data and 1891-1985 discharge data from Simpson et al (1993))

This temperature ~ rainfall relationship is particularly evident in desert areas far from any marine influence.  Alice Springs provides a good example.  Figure 1 shows how annual maximum temperatures at Alice Springs Airport vary with rainfall since 1997.  Data are from ACORN.

Fig. 1: Tmax and Rainfall, Alice Springs

The slope of the trend line shows that for every extra millimetre of rain, Tmax falls by 0.0047 of a degree Celsius, which is about half a degree less for every 100 mm.  The R-squared value shows that there is a good fit for the data- 79% of temperature change is due to rainfall.

I said above that this relationship holds for land locations.  An island, with a little land surrounded by water, is mostly affected by sea temperature and wind direction.  Locations near the coast are also affected by marine influence.  At Amberley in south-east Queensland daily maximum temperature can be moderated by the time of arrival of a sea breeze or whether it arrives at all.  (Site changes also can change Tmax recorded.)

Fig. 2: Tmax and Rainfall, Amberley

Further inland, the relationship is strong: at Bathurst, there is 0.4C temperature variation per 100mm of rainfall and 61% of temperature change is due to rainfall alone.

Fig. 3: Tmax and Rainfall, Bathurst

The BOM has sophisticated algorithms for area averaging temperature and rainfall across Australia and provide national climate records back to 1900 for rainfall and 1910 for maxima.  Averaged across Australia individual station idiosyncrasies are submerged so that the 1997 to 2019 relationship between Tmax and rainfall is very strong (and similar to that of Alice Springs):

Fig. 4: Tmax and Rainfall, Australia 1997-2019

However, the relationship is not strong throughout the whole record:

Fig. 5: Tmax and Rainfall, Australia 1910-2019

The relationship from 1910 to 2019 is poor.

In the next figure I compare the Tmax – rainfall relationships for the first 10 years of the record with the last 10 years.

Fig. 6: Tmax and Rainfall, Australia, first and last decades

The trendlines are almost exactly parallel, with tight fits, showing strong relationships 100 years apart- but the trendline for 2010 to 2019 is about 1.7 degrees above that for 1910 – 1919.  How can that be?

It is possible to compare rainfall and temperature throughout the last 110 years.  In the next figure, rainfall is inverted and scaled down so as to match Tmax at 1910.

Fig. 7: Tmax and Inverted Scaled Rain, Australia

Running 10 year means allow us to see long term patterns of rainfall and temperature more easily:

Fig. 8: Tmax and Inverted Scaled Rain, Decadal Means, Australia

Rainfall has increased over the last 110 years (despite what you might hear in the media), and so apparently have maximum temperatures.  In the above figures Tmax and rainfall track roughly together until the mid-1950s, then Tmax takes off.

I calculated an “index” of temperature ~ rainfall variation by subtracting scaled, inverted rainfall from Tmax, commencing at zero in 1919.  This allows us to identify when temperature appears to diverge markedly from inverted rainfall:

Fig. 9: Index of Temperature ~ Rainfall Variation: Tmax minus Inverted Scaled Rain, Decadal Means, Australia

There is a small increase from the mid-1950s, but the really large divergence commences in the 1970s, with the decade from 1973 to 1982 about 0.6 units above the decade to 1972.  The index decreases to 1995, then there is another steep increase to 2007, and a final surge to 2019.

This index alone shows how poorly the official temperature record represents the temperature of the past.

 While there are other times, in the next figures I compare four periods: 1910 to 1972, 1973 to 1995, 1996 to 2007, and 2008 to 2019.  Here I use annual data.

Fig. 10: Tmax and Rainfall, Australia, four periods

Again, trendlines are almost parallel with similar slopes, showing that the Tmax ~ rainfall relationship is fairly constant for all periods- (about 0.5C per 100mm after 1995 and about 0.4C per 100mm before 1995).  However, the lines are separated.  Temperature for each later period is higher than the ones preceding, such that the temperature recorded now is about 1.5 degrees Celsius higher than it would have been for similar rainfall before 1973. And rainfall has increased in that time.

Global Warming Enthusiasts and apologists for the BOM will claim that these breaks between separate periods are real and caused by changes in circulation patterns due to climate change- in particular the Southern Annular Mode.  That will be the subject of Part 2.

Whatever the reasons, Australia wide the Tmax ~ rainfall relationship has remained constant for the past 110 years (as it should) but the temperatures reported in the Acorn dataset have increased by more than 1.5 degrees Celsius relative to rainfall.

Conclusion:

The ACORN-SAT temperature dataset is an unreliable record of Australia’s maximum temperatures.

Australia’s Wacky Weather Station Comparison 4: Penrith (NSW)

After surveying 666 weather stations across Australia and finding nearly half (49.25%) are not compliant with Bureau of Meteorology siting specifications, in this series of posts I compare daily temperature data from pairs of compliant and non-compliant stations. Here’s the first in this series.

Penrith and Richmond RAAF

These stations are in western Sydney, 16km apart.

Fig. 1:  Penrith map location per Google Maps

Fig.2:  Penrith and Richmond

Penrith Lakes AWS 67113 is beside a large area of excavation and bare soil, and 200 metres from a large artificial lake.

Fig. 3:  Penrith (Google satellite image 2019)

Richmond RAAF 67105 is at an Air Force base. It is open, flat, and at least 50 meters from any concrete or tarmac.

Fig. 4:  Richmond RAAF site plan 2016

Fig. 5:  Richmond RAAF (Google satellite image 2020)

Richmond is 6 metres higher than Penrith.  Both are Automatic Weather Stations with electronic temperature probes transmitting data every minute. While there can be no observer error, as we shall see there can be instrumental error.

Richmond RAAF is an ACORN station. The Bureau says in its Station Catalogue: “The region is a major growth corridor for Sydney and there is evidence of anomalous warming of minimum temperatures in recent years.”

If we plot all daily maxima from 2010 to 2019 for Richmond against Penrith, we see that temperatures match quite closely:

Fig. 6:  Tmax at Richmond as a function of Tmax at Penrith

Richmond is on average cooler than Penrith. A time series of the 31 day centred mean of the daily difference between them shows more detail:

Fig. 7:  31 day mean daily difference Penrith minus Richmond Tmax

Values above zero mean Penrith is warmer than Richmond; below zero, Penrith is cooler.  Most summers Penrith is warmer, and winters slightly cooler, though the record appears to have breakpoints in early 2012 and early 2016, and some unusually high values.

This is a plot of mean differences by month:

Fig. 8: 31 day mean daily difference Penrith minus Richmond Tmax by month

Penrith is warmer in every month, especially in summer, though there are some cooler values in every month.

Minimum temperatures at Richmond are much cooler than Penrith:

Fig. 9:  Tmin at Richmond as a function of Tmin at Penrith

Fig. 10:  31 day mean daily difference Penrith minus Eichmond Tmin

Penrith is 2C to 2.5C warmer in cooler months and up to 0.5C warmer in summer.

Fig. 11: 31 day mean daily difference Penrith minus Richmond Tmin by month

A note on accuracy:

The centred 31 day running correlation is useful for detecting inconsistencies.

Fig. 12:  Centred  31 day running correlation between Penrith and Richmond maxima

Fig. 13:  Centred  31 day running correlation between Penrith and Richmond minima

The much poorer correlation in the summer of 2013-2014 shows in Figures 7 and 10. Here are the actual minimum temperatures recorded:

Fig. 14:  Daily minima at Penrith and Richmond Summer 2013 – 2014

It appears that the Richmond probe began malfunctioning in mid-December and failed completely in mid-January. It failed again a few months later.

In recent years, Penrith Lakes AWS 67113 has recorded generally warmer maxima than Richmond RAAF 67105 in summer and comparable or slightly cooler maxima in winters. Minima are always much warmer at Penrith. This may be due to the proximity to the large artificial lake.

In this example, siting non-compliance has a large effect on temperature.

***

This will be the last comparison, as it is very difficult to identify non-compliant stations with nearby compliant sites with similar environment. We can conclude however that non-compliance with siting specifications affects temperatures recorded, which varies between locations. Sometimes maxima are much warmer, sometimes minima. Temperatures at 329 non-compliant stations cannot be regarded as reliable for weather or climate analysis.

Australia’s Wacky Weather Station Comparison 3: Echuca (Vic)

UPDATE 20/02/2020: As reader Phil has reminded me and as I said after Figure 5 below, Kyabram appears to be irrigated and so should be added to the non-compliant list (making 329 or 49.25% of checkable stations). Therefore these sites are not suitable for comparison as factors other than siting (e.g. cooling due to evapo-transpiration following irrigation) will affect temperature difference. It is very difficult to find compliant sites that are near enough to non-compiant stations- but these are still interesting sites.

After surveying 666 weather stations across Australia and finding nearly half (49.25%) are not compliant with Bureau of Meteorology siting specifications, in this series of posts I compare daily temperature data from pairs of compliant and non-compliant stations. Here’s the first in this series.

Echuca and Kyabram

These stations are about 170km north of Melbourne, about 33km apart.

Fig. 1:  Echuca map location per Google Maps

Fig.2:  Echuca and Kyabram

Echuca Airport 80015 is right beside a large gravel parking area and less than 40 metres from the tarmac aircraft parking area.

Fig. 3:  Echuca Airport (Google satellite image 2019)

Kyabram 80091 is at a former research station in an open paddock as the 2008 plan shows:

Fig. 4:  Kyabram site plan 2008

Fig. 5:  Kyabram (Google satellite image 2020)

Kyabram is 9 metres higher than Echuca.  Again, an important difference is that Echuca is a manual station with liquid-in-glass thermometers, while Kyabram is an Automatic Weather Station (installed 1998) with an electronic temperature probe transmitting data every minute. The satellite image shows the enclosure is not well maintained with what appears to be long grass. The area around the enclosure is probably irrigated so this station should probably be classified as non-compliant as well.

If we plot all daily maxima from 2010 to 2019 for Kyabram against Echuca, we see that temperatures match quite closely:

Fig. 6:  Tmax at Kyabram as a function of Tmax at Echuca

The trend equation shows Kyabram is on average cooler than Echuca. A time series of the 31 day centred mean of the daily difference between them shows more detail:

Fig. 7:  31 day mean daily difference Echuca minus Kyabram Tmax

Values above zero mean Echuca is warmer than Kyabram; below zero, Echuca is cooler.  Note that apart from a few brief episodes, Echuca is always warmer than Kyabram.

This is a plot of mean differences by month:

Fig. 8: 31 day mean daily difference Echuca minus Kyabram Tmax by month

Echuca is warmer in every month- apart from those brief periods shown in Figure 7.

Minimum temperatures don’t match as closely…

Fig. 9:  Tmin at Kyabram as a function of Tmin at Echuca

Fig. 10:  31 day mean daily difference Echuca minus Kyabram Tmin

Echuca is generally warmer. There are several examples of odd deviations.

Fig. 11: 31 day mean daily difference Echuca minus Kyabram Tmin by month

A note on accuracy:

The centred 31 day running correlation is useful for detecting inconsistencies.

Fig. 12:  Centred  31 day running correlation between Echuca and Kyabram maxima

Fig. 13:  Centred  31 day running correlation between Echuca and Kyabram minima

The weaker correlation in 2011 is coincident with the unusual difference as seen in Figure 10 and is worth a closer look.

Fig. 14:  Daily minima at Echuca and Kyabram Winter 2011

Here we see probable examples of temperatures being recorded on the wrong date.

In recent years, Echuca 80015, a manual station that does not comply with site specifications, has warmer maxima than its neighbour Kyabram 80091 except for brief episodes, and mostly warmer minima.

In this example, siting non-compliance has a large effect on temperature, but may affect both sites.

Australia’s Wacky Weather Station Comparison 2: Wagin (WA)

After surveying 666 weather stations across Australia and finding nearly half (49.25%) are not compliant with Bureau of Meteorology siting specifications, in this series of posts I compare daily temperature data from pairs of compliant and non-compliant stations. Here’s the first in this series.

Wagin and Katanning

These stations are about 200km south-east of Perth.

Fig. 1:  Wagin map location per Google Maps

Katanning is in a paddock 48.7km south-east of Wagin.

Fig.2:  Wagin and Katanning

Wagin 10647 is in the middle of a small town. The screen has a bare dirt path leading to it. It is 10 metres from a bitumen street. A colourbond fence is to the north-east and an 18 metre tree is less than 20 metres away. More trees are to the south.

Fig. 3:  Wagin (Google satellite image 2019)

Katanning 10916 is in an open rural setting, on a slope as the 2013 site plan shows:

Fig. 4:  Katanning site plan 2013

Fig. 5:  Katanning (Google satellite image 2020)

Katanning is 64 metres higher than Wagin, but the surrounding country is similar- dry, flat or gently sloping.  Again, an important difference is that Wagin is a manual station with liquid-in-glass thermometers, while Katanning is an Automatic Weather Station (installed 1998) with an electronic temperature probe transmitting data every minute.

If we plot all daily maxima from 2010 to 2019 for Katanning against Wagin, we see that temperatures match quite closely:

Fig. 6:  Tmax at Katanning as a function of Tmax at Wagin

The trend equation shows Katanning is on average more than 0.5C cooler than Wagin. A time series of the 31 day centred mean of the daily difference between them shows more detail:

Fig. 7:  31 day mean daily difference Wagin minus Katanning Tmax

Values above zero mean Wagin is warmer than Katanning; below zero, Wagin is cooler.  Note that apart from a brief episode in 2012, Wagin is always warmer than Katanning.

This is a plot of mean differences by month:

Fig. 8: 31 day mean daily difference Wagin minus Katanning Tmax by month

Wagin is warmer in every month- apart from a three month period in 2012 which shows in the black ellipse.

Minimum temperatures don’t match as closely…

Fig. 9:  Tmin at Katanning as a function of Tmin at Wagin

Fig. 10:  31 day mean daily difference Wagin minus Katanning Tmin

Wagin is warmer in summer but cooler in winter. Possibly, due to the sloping ground at Katanning, cold air flows downhill away from the screen in cool months, keeping recorded minima higher than in Wagin.

Fig. 11: 31 day mean daily difference Wagin minus Katanning Tmin by month

A note on accuracy:

The centred 31 day running correlation is useful for detecting inconsistencies.

Fig. 12:  Centred  31 day running correlation between Wagin and Katanning maxima

Fig. 13:  Centred  31 day running correlation between Wagin and Katanning minima

Although there are a couple of obvious inconsistencies in maxima, the correlation in minima has been much worse every year.

Fig. 14:  Daily difference in maxima

There are examples of up to 6 degrees difference on some days, and some much larger, possibly due to observation or recording error- for example, by recording temperature on the wrong day, or recording 19.6 instead of 29.6.

In recent years, Wagin 10647, a manual station that does not comply with site specifications, has warmer maxima than its compliant neighbour Katanning 10916 all year round, and has warmer minima in summers. 

In this example, siting non-compliance has a large effect on temperature.

Australia’s Wacky Weather Station Comparison 1: Keith (SA)

After surveying 666 weather stations across Australia and finding nearly half (49.25%) are not compliant with Bureau of Meteorology siting specifications, in this series of posts I compare daily temperature data from pairs of compliant and non-compliant stations.

The difficulty is to find pairs of sites in close physical proximity and similar surroundings.  Large numbers of non-compliant stations especially in WA and SA have no compliant neighbours. 

Another difficulty is that it is impossible to control variables other than siting.  Screen maintenance, enclosure maintenance, probe or thermometer accuracy, are some of the variables that may adversely affect comparisons.  Never-the-less, we shall try.

I have restricted analysis to the last 10 years (2010 – 2019).

Keith and Munkora

These stations are in the far south-east of South Australia, not far from the Victorian border:

Fig. 1:  Keith map location per Google Maps

 They form the closest pair of stations I have found, just 2.66 kilometres apart, as this map shows.

Fig.2:  Keith and Munkora (Keith West)

Keith 25507 is in the middle of town between the highway and the rail line between Adelaide and Melbourne.

Fig. 3:  Keith (Google satellite image 2019)

Munkora 25557 is in an open rural setting, but is really “marginal” rather than compliant, as the grass in the enclosure is up to 0.5m high, and the surrounding paddock has at times been a cultivation, as the 2017 site plan shows:

Fig. 4:  Munkora site plan 2017

Still, it’s better than Keith.

Fig. 5:  Munkora  (Google satellite image 2020)

There is only 2 metres difference in altidude.  However, an important difference is that Keith is a manual station with liquid-in-glass thermometers, while Munkora is an Automatic Weather Station (installed 2001) with an electronic temperature probe transmitting data every minute.

If we plot all daily maxima from 2010 to 2019 for Munkora against Keith, we see that temperatures match quite closely:

Fig. 6:  Tmax at Munkora as a function of Tmax at Keith

A time series of the 31 day centred mean of the daily difference between them shows more detail:

Fig. 7:  31 day mean daily difference Keith minus Munkora Tmax

Values above zero mean Keith is warmer than Munkora; below zero, Keith is cooler.  Note that Keith is warmer in cooler months but Munkora is warmer in summer and autumn.  Note also strange things happen in the summers of 2010-2011, 2014-2015, and 2015-2016.

This is a plot of mean differences by month:

Fig. 8: 31 day mean daily difference Keith minus Munkora Tmax by month

Keith is warmer in cool months (May to September).  However, the warmer maxima at Munkora in warmer months may be due to the rapid response of the AWS probe to sudden temperature changes which an LIG maximum thermometer will not detect.  The BOM denies this happens.

Minimum temperatures don’t match as closely…

Fig. 9:  Tmin at Munkora as a function of Tmin at Keith

But minima at Keith are consistently warmer (averaging about 1.5 degrees C) than 2.7km out of town, and the differences are much greater:

Fig. 10:  31 day mean daily difference Keith minus Munkora Tmin

Keith is warmer in all seasons, especially spring and summer.

Fig. 11: 31 day mean daily difference Keith minus Munkora Tmin by month

A note on accuracy:

The centred 31 day running correlation is useful for detecting inconsistencies.

Fig. 12:  Centred  31 day running correlation between Keith and Munkora maxima

Fig. 13:  Centred  31 day running correlation between Keith and Munkora minima

Although there are a couple of obvious inconsistencies in maxima, the correlation in minima has been getting worse over the years and was much worse in 2019.

Fig. 14:  Daily difference in minima

There are examples of up to 10 degrees difference on some days, possibly due to observation or recording error- for example, by recording temperature on the wrong day.

In recent years, Keith 25507, a manual station that does not comply with site specifications, has warmer winter maxima but cooler summer maxima than the AWS at Munkora 25557 just 2.66km out of town, and has warmer minima all year round. 

Keith, with a population of just over 1,000, appears to have an Urban Heat Island (UHI) effect, due to its poor siting.

In this example, siting non-compliance has a large effect on temperature.

Australia’s Wacky Weather Stations: Final Summary

(Updated 17/01/2020)

Australia, being a wealthy, modern, western nation with a very well-resourced Bureau of Meteorology (BOM), might be expected to have weather stations that set a high standard of siting and reliability.

Unfortunately, that is far from the case.  This pie chart shows the percentage of weather stations that comply with siting specifications, don’t meet those specifications, or are “marginal”- not fully compliant but not as bad as some.

Nearly half do not comply with siting guidelines as outlined in Observation Specification No. 2013.1 (drafted in January 1997).

Less than a third comply and may be relied on (assuming that the screen and the immediate area around it is kept well maintained with a few centimetres of natural grass, and the surrounding environment does not change).

The marginal stations may or may not be reliable.

In Australia it is apparently quite OK to have thermometers beside houses, in bitumen carparks, in a vegetable garden surrounded by a corrugated iron fence, beside incinerators, behind 6 metre prison walls, beside piles of human excrement, in the middle of a dirt road, on the roof of a wharf shed, beside a multi-lane highway, shaded by trees, or in screens that are covered in spider webs, invaded by mud wasps, or used by cattle as a back-scratcher.  The area around the screens can be dusty bare dirt, overgrown with grass and weeds, or sprayed out to bare ground.

This map, thanks to Lance Pidgeon, shows the locations of weather stations audited.

As you can see, removing non-compliant and marginal sites leaves very large gaps.

Australia’s climate analysis is based on 112 stations in the ACORN-SAT network.  I surveyed 111 Acorn stations.  (Wittenoom stopped reporting in July 2019 and is now apparently closed).  Here is a pie chart of Acorn station compliance:

Again, thanks to Lance, this is a map of Australian Acorn stations….

…and this map shows the layout of the Acorn network with non-compliant stations removed, leaving marginal and compliant sites.

Only New South Wales has a decent density of compliant sites.  There are huge gaps in Queensland, Western Australia, and South Australia.  No wonder the Bureau is desperately defending their realm!

Here are the non-compliant Acorn sites.

Adelaide (Kent Town)	Mackay
Albany Airport	Marble Bar
Barcaldine	Marree Airport
Bridgetown	Melbourne (Olympic Park)
Camooweal	Merredin
Cape Borda	Mildura
Cape Bruny	Miles
Cape Leeuwin	Morawa Airport
Cape Moreton	Moruya Heads
Cape Otway	Nuriootpa
Charters Towers	Point Perpendicular
Coffs Harbour Airport	Richmond (Qld)
Cunderdin Airport	Robe
Dalwallinu	Rockhampton
Deniliquin	Rutherglen
Geraldton Airport	Scone Airport
Giles	Snowtown
Halls Creek	Sydney – Observatory Hill
Hobart	Townsville
Kalumburu	Wandering
Kerang	Wilcannia Airport
Kyancutta	Wilsons Promontory
Larapuna (Eddystone Point)	Woomera
Longreach	Yamba

Summary

Of 666 weather stations I was able to identify and survey, nearly half (328) did not comply with siting specifications.

Less than a third (209) fully comply (assuming that the screens and surroundings are well maintained).

Another 129 are marginal- not fully compliant but not as bad as the non-compliant sites.

48 of the 111 remaining Acorn stations are not compliant, and a further 22 are marginal.

The Bureau of Meteorology starts its climate analysis using Acorn from 1910.  Reasons given are that the network, especially in remote areas, and also Western Australia and Tasmania,  was extremely sparse before this, and except in Queensland and South Australia (where Clement Wragge had instituted Stevenson screens and standardised practises by the mid-1890s) temperature observations and instrument siting were non-standard.  Temperature records before 1910 are not recognised by the Bureau.  For example, the hottest temperature recorded, 53.1C at Cloncurry on 16 January 1889 is discounted as it was not recorded in a Stevenson screen; and the temperature of 51.6C in Bourke on 3 January 1909 is discounted, even though it was in a Stevenson screen.  How can we be any more confident in current temperatures recorded at non-compliant sites?

With only 209 stations of the 666 surveyed fully complying with specifications, doubt must be raised not only about the modern network coverage but also the reliability and comparability of modern and historical temperature records.

The next step:

Over some time, I will be comparing data from several pairs of compliant and non-compliant stations to see if siting has any detectable effect on temperatures recorded.

Appendix:- Background and details of survey: 

In July 2019 I commenced a 6 month long survey of 666 weather stations that currently report temperatures to the Latest Weather Observations pages for each state (also to Climate Data Online and to international weather and climate agencies).  Many are used to make adjustments to Acorn stations. Of the 753 stations listed (and these change from time to time) I was able to identify and examine 666. 

I did not include offshore island territories or islands far distant from the mainland (e.g. Willis island) but islands close to the coast were included.  Other stations not included were those in the National Tidal Centre network, which are located on wharves and breakwaters and have beehive screens instead of Stevenson screens; Lucas Heights nuclear facility; a number of recent defence stations that were impossible to locate; stations in areas where satellite imagery has poor resolution, and a number of sites that have not yet been included in the BOM metadata and thus have no site plans and can’t be located- a good example is Wellcamp Airport in southern Queensland. (See below for the full list.)

The process I used is outlined  in my post “How to check for yourself”.  I also made use of information and photographs supplied by colleagues with local knowledge.

There are 328 examples of stations that are not compliant with specifications, listed by state here.

This is an example of a compliant station:  Amberley AMO  40004 which is an Acorn station.

Google satellite image: 

This is an example of a marginal station:  Nullo Mountain 62100

Google satellite image: 

It has patches of rougher/ longer vegetation nearby and a large tree about 20 metres away.

(And the more I look at marginal sites the more I find that I should really have classified more as not compliant.)

These are the marginal stations (Acorn marked *):

Adelaide Airport	Middle Point
Armidale	Milingimbi
Batchelor	Moomba Airport
Batemans Bay	Mortlake
Bathurst *	Moss Vale
Boulia *	Mount Boyce
Bourke *	Mount Bundey North (Defence)
Bowen Airport AWS	Mount Crawford
Bradshaw-Angallari Valley (Defence)	Mount Ginini
Brisbane	Mount Ive
Brisbane Airport *	Mount Magnet Airport
Bulman	Mount Moornapa
Burketown Airport *	Mudgee
Cape Grim	Nambour
Cape Sorell	Neptune Island
Central Arnhem Plateau	New May Downs
Cerberus	Ngayawili (Elcho Island)
Charlton	Ngukurr AWS
Combienbar	Nhill Aerodrome *
Cooktown	Noarlunga
Coonawarra	Noonamah
Cootamundra	Nullo Mountain
Cowley Beach (Defence)	Oakey
Cultana (Defence)	Oodnadatta *
Darwin Airport *	Orbost *
Derby	Palmerville *
Devonport Airport	Parramatta
Dum In Mirrie	Pearce
Dwellingup	Port Augusta
Eildon Fire Tower	Port Fairy
Elliott	Portland Airport
Esperance Airport	Redland (Alexandra Hills)
Essendon Airport	Rhyll
Eucla *	Sheffield
Fingal	Sheoaks
Forrest *	Shepparton
Fowlers Gap	St George *
Gabo Island *	Stawell
Gelantipy	Stenhouse Bay
Grafton Airport	Swan Hill
Grove *	Sweers Island
Hamilton Island	Sydney Olympic Park
Horn Island *	Tabulam
Hume Reservoir	Tarcoola *
Hunters Hill	Taree Airport
Jervis Bay Airfield	Temora
Jervois	Tennant Creek *
kunanyi / Mount Wellington	Terrey Hills
Kununurra Airport	Thargomindah *
Lake Julius	The Monument
Lake Macquarie – Cooranbong	Tibooburra Airport *
Lake St Clair	Tocal
Lancelin (Defence)	Townsville Air Weapons Range (Defence)
Launceston Airport *	Trepell
Laverton (WA)	Tunnack
Legendre Island	Turretfield
Leigh Creek	Victor Harbor
Leonora Airport	Wadeye (Port Keats)
Lombadina	Warruwi
Lostock	White Cliffs AWS
Low Head *	Windorah
Luncheon Hill	Woolbrook
Mackay Airport	Yanakie
McArthur River Mine	Young
Melbourne Airport

These are the stations listed in Latest Weather Observations that I did not use (plus offshore island territories). You are welcome to try- let me know if you have any success.

Adele Island	Melville Water
Arlington Reef	Middle Percy Island
Banana Bank	Mount Buller
Barrow Island	Mount Bundey South (Defence)
Bedout Island	Mount Hope
Bradshaw-Koolendong Valley	Mount Hotham Airport
Brewon	Mount Keith
Broome Port	Mount Read
Browse Island	Mulurulu
Bulga Downs	Noona
Burnie Port	North Head
Busselton Jetty	North Island
Canungra (Defence)	Oberon
Cape Ferguson	Ocean Reef
Cape Wessel	Outer Harbor (Black Pole)
Christmas Creek	Paynes Find
Colpoys Point	Point Avoid
Coondewanna	Port Kembla Harbour
Croker Island Airport	Portland Harbour
Darwin Harbour	Puckapunyal-Lyon Hill (Defence)
Degrussa Aerodrome	Rosslyn Bay Harbour
Doongan	Rowley Shoals
Edi Upper	Sellicks Hill
Esperance Harbour	Smithville
Evans Head	Solomon Airport
Fawkner Beacon	South Channel Island
Fort Denison	Spitfire Channel
Fortescue Dave Forrest	Spring Bay
Frankston	St Kilda Harbour RMYS
Gluepot	Swan Island
Gooseberry Hill	Sydney Harbour
Hay Point	Thevenard Island
Heron Island	Thursday Island
Hillarys Point Boat Harbour	Townsville – Fanning River (Defence)
Hindmarsh Island	Troughton Island
Inner Beacon	Urandangi
Kingfish B	Varanus Island
Kurnell	Warburto Point
Little Bay	Warburton
Lochington	Wattamolla
Low Rocky Point	Wellcamp Airport
Lucas Heights (ANSTO)	West Roebuck
Maatsuyker Island	Yampi Sound (Defence)
Maitland Airport

The Wacky World of Weather Stations by State

Here are 328 Australian weather stations that are not compliant with Bureau of Meteorology specifications for siting.

Site compliance is important because temperature data from these stations is liberally reported in the media especially if hot or cold records are set. They also contribute to AWAP (the Australian Water Availability Project) and ADAM which produce maps of present and past temperatures. As well, data from these stations is used to homogenise data at stations in Australia’s ACORN-SAT network, which are used for showing trends since 1910. Finally, this data is exported to be used by international databases (GISS, CruTem4) for regional and global climate analysis. If the data is affected by site specific factors, e.g being too close to a road, this may affect the quality of the analysis.

I am agnostic as to the overall effect of these poorly sited stations. Maxima at some sites may be artificially low, or minima may be artificially high, and this may vary with seasons and rainfall. Analysis and comparison of temperatures will come later. My focus here is to show the large number of modern stations whose data may be unreliable.

The quality of these non-compliant stations varies. While some are truly horrendous, others are not nearly as bad, but all fail on one or more specifications.

Find your favourite station, click on it, and the link will take you to my assessment of its siting quality. Use the back arrow to return here.

South Australia	Victoria
Adelaide (SA)	Aireys Inlet (Vic)
Andamooka (SA)	Ararat (Vic)
Arkaroola (SA)	Avalon (Vic)
Cape Borda (SA)	Bairnsdale (Vic)
Cape Willoughby (SA)	Ben Nevis (Vic)
Cleve (SA)	Cape Nelson (Vic)
Cleve Airport (SA)	Cape Otway (Vic)
Cummins Airport (SA)	Castlemaine (Vic)
Edinburgh (SA)	Coldstream (Vic)
Edithburgh (SA)	Dartmouth (Vic)
Elliston (SA)	Echuca Airport (Vic)
Eudunda (SA)	Falls Creek (Vic)
Kadina (SA)	Ferny Creek (Vic)
Karoonda (SA)	Horsham (Vic)
Keith (SA)	Kerang (Vic)
Kimba (SA)	Lake Eildon (Vic)
Kingscote (SA)	Lakes Entrance (Vic)
Kuitpo (SA)	Latrobe Valley  (Vic)
Kyancutta (SA)	Longerenong (Vic)
Lameroo (SA)	Maryborough (Vic)
Loxton (SA)	Melbourne (Vic)
Maitland (SA)	Mildura (Vic)
Marree (SA)	Moorabbin (Vic)
Meningie (SA)	Mount Nowa Nowa (Vic)
Minlaton Aero (SA)	Mount William (Vic)
Minnipa (SA)	Omeo (Vic)
Mount Barker (SA)	Point Hicks (Vic)
Mount Lofty (SA)	Redesdale (Vic)
Murray Bridge (SA)	Rutherglen (Vic)
Naracoorte (SA)	Scoresby (Vic)
Nullarbor (SA)	Tatura (Vic)
Nuriootpa (SA)	Viewbank (Vic)
Padthaway (SA)	Walpeup (Vic)
Pallamana (SA)
Price (SA)	Wangaratta (Vic)
Robe (SA)	Warracknabeal (Vic)
Roseworthy (SA)	Warragul (Vic)
Snowtown (SA)	Warrnambool (Vic)
Streaky Bay (SA)	Westmere (Vic)
Warooka (SA)	Wilsons Promontory (Vic)
Whyalla (SA)	Wonthaggi (Vic)
Woomera (SA)
Yongala (SA)	Tasmania
	Bushy Park (Tas)
Northern Territory	Cape Bruny (Tas)
Black Point (NT)	Cape Bruny AWS (Tas)
Centre Island  (NT)	Cressy (Tas)
Charles Point (NT)	Dover (Tas)
Curtin Springs (NT)	Flinders Island Airport (Tas)
Jabiru (NT)	Friendly Beaches (Tas)
Kangaroo Flats (NT)	Hartz Mountain (Tas)
Kintore (NT)	Hobart (Tas)
Kulgera (NT)	Lake Leake (Tas)
Lajamanu Airport (NT)	Larapuna (Eddystone Pt) (Tas)
Murganella Airstrip (NT)	Launceston (Tas)
Pirlangimpi (NT)	Marrawah (Tas)
Point Fawcett (NT)	Maydena (Tas)
Point Stuart (NT)	Orford (Tas)
Territory Grape Farm (NT)	Ouse (Tas)
Yulara Airport (NT)	Scotts Peak (Tas)
	Strahan (Tas)
	Warra (Tas)
	Wynyard (Tas)
West Australia	New South Wales
Albany (WA)	Albury (NSW)
Albany Airport (WA)	Balranald (NSW)
Argyle (WA)	Bankstown (NSW)
Badgingarra (WA)	Barraba (NSW)
Barimunya (WA)	Bathurst Airport (NSW)
Beverley (WA)	Bombala (NSW)
Bickley (WA)	Bombala AWS (NSW)
Bidyadanga (WA)	Brewarrina (NSW)
Bridgetown (WA)	Burrinjuck Dam (NSW)
Busselton (WA)	Cape Byron (NSW)
Cape Leeuwin (WA)	Cobar Airport (NSW)
Cape Naturaliste (WA)	Coffs Harbour (NSW)
Carnamah (WA)	Collarenebri (NSW)
Carnegie (WA)	Coonabarabran (NSW)
Collie East (WA)	Coonabarabran Airport (NSW)
Corrigin (WA)	Cowra (NSW)
Cunderdin (WA)	Deniliquin (NSW)
Cygnet Bay (WA)	Dunedoo (NSW)
Dalwallinu (WA)	Forster (NSW)
Denham (WA)	Grafton Airport (NSW)
Donnybrook (WA)	Green Cape (NSW)
Eyre (WA)	Grafton AgRS (NSW)
Geraldton Airport (WA)	Griffith (NSW)
Giles (WA)	Gulgong (NSW)
Goomalling (WA)	Gundagai (NSW)
Gosnells City (WA)	Guyra (NSW)
Halls Ck (WA)	Hillston (NSW)
Hopetoun North (WA)	Holsworthy (Defence) (NSW)
Hyden (WA)	Katoomba (NSW)
Jacup (WA)	Lake Cargelligo (NSW)
Jarrahwood (WA)	Lake Victoria (NSW)
Jurien Bay (WA)	Lightning Ridge (NSW)
Kalbarri (WA)	Lismore Airport (NSW)
Kalumburu (WA)	Mangrove Mountain (NSW)
Karijini North (WA)	Menindee (NSW)
Karratha (WA)	Merimbula (NSW)
Kellerberrin (WA)	Montague Island (NSW)
Lake Grace (WA)	Moruya Heads (NSW)
Lancelin (WA)	Mount Seaview (NSW)
Leinster (WA)	Mungindi  (NSW)
Mandora (WA)	Murrurundi (NSW)
Mandurah (WA)	Murwillumbah (NSW)
Manjimup (WA)	Narooma (NSW)
Marble Bar (WA)	Nelson Bay (NSW)
Merredin (WA)	Newcastle (NSW)
Millendon (WA)	Newcastle Univ. (NSW)
Morawa (WA)	Norah Head (NSW)
Mount Elizabeth (WA)	Nyngan (NSW)
Mount Barker (WA)	Parkes (NSW)
Mullewa (WA)	Peak Hill (NSW)
Munglinup West (WA)	Penrith (NSW)
Murchison (WA)	Perisher Valley (NSW)
Narembeen (WA)	Pindari Dam (NSW)
Narrogin (WA)	Pooncarrie (NSW)
Newman Aero (WA)	Point Perpendicular (NSW)
Northam (WA)	Quirindi (NSW)
Ongerup (WA)	Scone (NSW)
Pemberton (WA)	Singleton (NSW)
Perth Metro (WA)	Smoky Cape (NSW)
Pingelly (WA)	Springwood (NSW)
Ravensthorpe (WA)	Sydney  (NSW)
Red Rocks Point (WA)	Sydney Airport (NSW)
Salmon Gums RS (WA)	Taralga  (NSW)
Shark Bay Airport (WA)	Tenterfield (NSW)
Southern Cross (WA)	Thredbo Village (NSW)
Swanbourne (WA)	Tocumwal (NSW)
Telfer (WA)	Tumbarumba (NSW)
Wagin (WA)	Ulladulla (NSW)
Warmun (WA)	Wanaaring (NSW)
Wiluna (WA)	Wellington (NSW)
Witchcliffe (WA)	Wilcannia Airport (NSW)
Wongan Hills (WA)	Yamba (NSW)
York (WA)	Yanco (NSW)
Wandering (WA)
Queensland
Alva Beach (Qld)	Low Isles (Qld)
Applethorpe (Qld)	Lucinda (Qld)
Ayr DPI (Qld)	Mackay MO (Qld)
Barcaldine (Qld)	Mareeba (Qld)
Beaudesert (Qld)	Miles (Qld)
Bedourie (Qld)	Mitchell (Qld)
Bollon (Qld)	Mornington Is Airport (Qld)
Cape Flattery (Qld)	Mount Isa  (Qld)
Cape Moreton (Qld)	Mount Stuart Defence (Qld)
Camooweal (Qld)	Point Lookout (Qld)
Cardwell (Qld)	Rainbow Beach (Qld)
Century Mine (Qld)	Redcliffe(Qld)
Charters Towers (Qld)	Richmond (Qld)
Coconut Island (Qld)	Rockhampton (Qld)
Collinsville (Qld)	Rolleston (Qld)
Cunnamulla (Qld)	Rundle Island (Qld)
Double Island Point (Qld)	Sandy Cape (Qld)
Emerald (Qld)	Seventeen Seventy (Qld)
Gladstone Airport (Qld)	Springsure (Qld)
Gladstone Radar (Qld)	Stanthorpe (Qld)
Gold Coast Seaway (Qld)	South Johnstone (Qld)
Greenbank (Qld)	Sunshine Coast Airport (Qld)
Gympie (Qld)	Surat (Qld)
Hervey Bay (Qld)	Tambo (Qld)
Ingham (Qld)	Taroom (Qld)
Injune (Qld)	Tewantin RSL Park (Qld)
Innisfail (Qld)	Texas (Qld)
Innisfail Aero (Qld)	Tin Can Bay (Qld)
Kowanyama Airport (QLD)	Townsville (Qld)
Lady Elliott Island (Qld)	Woolshed (Qld)
Logan City (Qld)	Yeppoon (Qld)
Longreach (Qld)

The Wacky World of Weather Stations: No. 328- Ferny Creek (Vic)

Friday 10/01/2020

Please refer back to my first post for site specifications and to No. 92- Logan City for 2018 specifications.  If you wish to check on this (or any) site for yourself, go to my post on how to check for yourself.

Station: Ferny Creek 86266

Opened: 2011

Daily Temperature data from: 2011

Data used to adjust Acorn sites at: —

Co-ordinates: -37.8748 145.3496

35km east of Melbourne CBD.

BOM site plan 2018:

Google satellite image:

Google ‘street’ view 2019 (photo Glenn Batchelor):

Drone photo:

The screen is on sloping land and is a few metres from shrubs; a 50m tall tree is about 40 metres away.

This station is non-compliant, with temperatures reported at Latest Weather Observations  but not used to adjust data at Acorn sites.

FAIL

Percentage of all sites non-compliant: 49.25%.

That’s it: I think I’ve finished. Next I’ll update the index.

The Wacky World of Weather Stations: No. 327- Lake Grace (WA)

Friday 10/01/2020

Please refer back to my first post for site specifications and to No. 92- Logan City for 2018 specifications.  If you wish to check on this (or any) site for yourself, go to my post on how to check for yourself.

Station: Lake Grace 10911

Opened: 1997

Daily Temperature data from: 1997

Data used to adjust Acorn sites at: Esperance

Co-ordinates: -33.1006 118.4647

275km south-east of Perth

BOM site plan 2015:

Google satellite image:

Google street view 2008:

The screen is 15 metres from a bitumen road, 36 metres from a bitumen carpark, and 18 metres from the railway track. It is also close to bare dirt. Further, in 2008, either the area was watered or else the natural grass was worn away or removed to bare dirt to within a few metres.

This station is non-compliant, with temperatures reported at Latest Weather Observations  and used to adjust data at Acorn sites.

FAIL

Percentage of all sites non-compliant: 49.1%.