Archive for February, 2010

Cherries, anyone? Another data “trick” in Australia

February 23, 2010

Ken Stewart, February 2010

Update: 25-02-10

I have improved the graphs after readers’ suggestions and assistance from Jo Nova.  I have revised the GISS warming from 1.7 to “over 1.6” degrees /100 years.

As a follow up to my analysis of temperature data for Mackay and Te Kowai, this study compares Goddard Institute of Space Studies (GISS) data with data from the Bureau of Meteorology for Gladstone and “nearby” sites in regional Queensland, and finds further inexplicable treatment of data leading to an exaggerated warming trend.

Gladstone is an old port, meatworks, and fishing town, now an industrial city with a power station, bauxite refinery and aluminium smelter, plus a coal terminal.  Interestingly, GISS makes NO homogenisation adjustment for Gladstone, and that aroused my curiosity.

 

The Australian Bureau of Meteorology (BOM) has 3 records for Gladstone.  The Post Office from 1909 to 1956 which is dead flat at about 22 degrees; Gladstone Radar from 1958 to 2009, which is immediately 1 degree warmer, and the Airport from 1994  to 2009, half to 1 degree cooler than Radar.  Please note: all my analysis is from 1908-2009, 102 years.  BOM data starts at 1909.

GISS get their data directly from GHCN (Global Historical Climatology Network). Which do you think GISS/GHCN uses? 

The warm one of course.  But how they use it is cynical- and informative.

When developing station data, GISS state that Step 1 is “combining sources at the same location”.  While GISS correctly claim they make no adjustment to their Gladstone data, GHCN/GISS have  “accidentally” ignored 41 years of the earlier BOM data, which shows a flat trend at about 22 degrees.  They have also completely ignored data from the Airport which is about 0.8 degree below Radar.   

But- and this is critical- they splice the last 6 years from the PO onto Gladstone Radar.  Have a closer look at this.

The Radar data is about 1 degree warmer than the PO. Making a trend from this spliced data is very questionable.   As well, the data for Radar shows an upwards movement of about 0.5 degree in the last decade. 

Possibly GISS would say they’re only interested in 1951-1980 figures.  However this has the effect of dropping the starting point.

The result is a warming trend of over1.6 degrees per 100 years where none can reasonably be calculated.  The best they could reasonably have hoped for, by leaving out those 6 years might be about 1.5 degrees per 100 years, which is close but leaves out a lot of data, or by splicing the PO with the Airport, about 0.9 degrees.  Here are plots of these two options:

Option 1- Radar trend, with PO 1951-1956 deleted (1.5 C):

 

Option 2- Post Office spliced with Airport (0.9C):

I would propose a far better solution: they could have adjusted Radar down by 0.8 degrees (the average difference from Airport) to produce this:

Option 3- Radar adjusted -0.8C for Airport, then spliced to PO (0.7C):

Now isn’t that a more elegant solution?  That produces a trend of ~ 0.7 degrees per Century.

So perhaps GHCN chose this 1.6 degrees per century slope to match that of nearby rural stations?  Well actually, no, nothing matches. Then perhaps GISS homogenises Gladstone’s data to match the mean of neighbouring stations.  No again- GISS have not made any adjustments for “inhomogeneities” such as station movement from PO to Radar.   I have included the graphs and notes in an Appendix below for you to check- I find them interesting.  For the sake of brevity, I will skip straight to the conclusion.

Conclusion:

Although GISS can truthfully say they have not adjusted the GHCN data, the splicing of the last 6 years of the Post Office dataset to the warmer Gladstone Radar leads to a trend of more than 1.6 degrees Celsius per Century. 

I have shown three possible options for more appropriate adjustments to combine all temperatures at the one site. Of these, the highest trend is about 1.5 degrees, which is close to the trend (1.4 degrees) of the nearest rural sites.  Examination of these sites shows that their data is of questionable quality.  The second option produces a trend of 0.9 degrees, and the third and (in my opinion) best option, 0.7 degrees. The average trend of the 5 nearest long-record rural sites (0.8 degrees) is between these last two options and so matches well.  Nearby cities of Rockhampton and Bundaberg show adjusted trends of about 0.7 and 0.5 degrees respectively, and Maryborough, ignored by GHCN, shows a trend of 0.4 degrees. 

Thus the GISS record for Gladstone is derived from cynically cherry-picked data.  The resulting trend of more than 1.6 degrees Celsius per Century cannot be justified.  The record is false.  

At the GISS website, the responsible NASA official is listed as Dr James Hansen.  I will leave it to others to decide what he is responsible for.

References

http://data.giss.nasa.gov/gistemp/station_data/

http://www.bom.gov.au/climate/data/weather-data.shtml

http://www.bom.gov.au/other/disclaimer.shtml

http://www.bom.gov.au/other/copyright.shtml#acknowledgements

http://www.appinsys.com/GlobalWarming/climap.aspx?area=australia

Appendix

Mt Morgan has a cooling trend but has many gaps.

Biloela DPI, like many stations,  has a gap of 8 years from 1956-1965.  When the data resumes, it has jumped by 0.5 degree and  continues rising at this 2 degrees/ 100 years rate.  Why would a rural site, only 83 km from Mt Morgan, be warming at this rate?  Interesting.

Yeppoon’s data is too short and patchy to be much use.

Monto has a patchy record with gaps, only from 1962.  It also shows a trend of 2 degrees per 100 years.  The airport’s very scanty data appears to be half to 1 degree below the township.  What happened to the data before 1962?  Monto was settled in the 1920s.  GISS calls it “Monto Post Office was 03”.  What was the “03” ?  Without the missing data no conclusions can be reached.

Lady Elliott Island shows a trend of about 1.6 degrees warming, but note the cooling, warming, cooling- very interesting.  I will check coastal and island data in a later study.

Baralaba’s record is far too short and patchy.

Although the average of  these 4 stations (excluding Yeppoon and Baralaba) of 1.4 degrees is still less than the warming at Gladstone shown by GISS/GHCN, the data quality may not be good enough to  use any of these except Lady Elliott Island to “justify” Gladstone’s data.  Let’s look at some longer records.

Childers has a trend of about 0.9 degree per 100years (according to GISS),  but only about 0.2 degree up to 1956 when there’s an 8 year gap.

Gayndah, one of the oldest towns in Queensland, shows a linear trend of about 1.4 degrees /100 years.  Note the 4th order polynomial clearly shows the flat trend to the 1950s, and the 1.1 degree rise since then.  Incidentally, Gayndah’s record goes back to 1893, with the hottest year on record being 1897, but I will stick with my 102 year analysis as that matches the majority of long records and BOM is not confident about much data before 1910.

Sandy Cape Lighthouse shows a linear trend of about 0.5 degree/ century, and a small cycle is very evident.  Note the 1940s.

Gympie is 291km south, and a large regional town, once a roaring gold rush town.  GISS shows a trend of about 0.5 degrees/Century, and BOM 0.3 degrees.  30 years cooling!

Emerald, 316km inland, shows maybe 0.8 degrees over 100 years.  Note the large step up (UHI effect?), after a declining trend, from the 1970s onwards, when the town boomed with expansion of irrigation, then coal mining.  Also note the warm period in the early 20th Century.  Airport data seems flat or lower.  Handle cautiously.

The average of these long term stations’ trends is 0.8 degrees- midway between my adjustment Options 2 and 3.

Next, let’s compare Gladstone with its next door cities, Rockhampton, 95 km north, and Bundaberg, 159 km south, both adjusted appropriately.  I will be studying their adjustments in detail in the near future.

 Rocky– adjusted trend about 0.7 degree.

Bundy– adjusted trend about 0.5 degrees.

Even more interesting is a station that GHCN and GISS totally ignore- Maryborough, a small city with a long record, about 240 km south. 

The trend?  Maybe 0.4 degrees.

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Post Script to GISS at Mackay

February 12, 2010

UPDATE:

Breaking News:  An initial brief look at the data suggests data manipulation at Cairns and Mount Isa and something very strange at Gladstone!  I will be checking this in the next few days- watch for another post.

I have made a number of small changes to my original post below.  These mainly reflect a revision of data for Barcaldine and Willis Island, and some small text changes.  I no longer claim GHCN data is  “out”, just much of it is inexplicably missing. 

These changes have not made any change to the overall conclusions. 

The adjustments, presumably for Urban Heat Island effect, are UPWARDS for both Te Kowai and Mackay, when any correction should try to reduce the effect. 

In contrast, Mackay’s neighbouring regional cities of Rockhampton (330 km south) and Townsville (400km north) both have been adjusted correctly (although I have yet to verify the surrounding rural stations). 

Rocky:

Townsville:

Those who mistake me for a ratbag denialist who sees no good at all in the opposite camp, please note:  it seems GISS can adjust temperatures for UHI correctly when they want to. 

The question remains: why did they make such unwarranted adjustments to Mackay, and why did they make such a huge reversal to Te Kowai (Mackay Sugar Mill Station)?

Thank you to readers who have given me much encouragement.  I am very chuffed by your support.

Ken

GISS manipulates climate data in Mackay (3rd Edition)

February 5, 2010

Another Smoking Gun from Australia?   How GISS adjusts temperature records in two adjacent sites

Ken Stewart, January 2010

(Updated November 2010 with better graphs)

Introduction

Despite its assurances, GISS has adjusted the temperature records of two sites at Mackay to reverse a cooling trend in one and increase a warming trend in another.   This study presents evidence that this is not supportable and is in fact an instance of manipulation of data.

I decided to have a look at the temperature records of the weather stations closest to where I live, near Mackay in North Queensland.  The Bureau of Meteorology lists 3 current stations: Mackay MO, Mackay Aero, and Te Kowai Exp Station, plus the closed station Mackay Post Office.  GISS has a list of nearby stations.  One is “Mackay Sugar Mill Station”.  I had never heard of it.  Te Kowai Exp Station, only a few kilometres from Mackay, is in fact at the same co-ordinates as Mackay Sugar Mill.  I checked on AIS for the GHCN  site, and there is Mackay Sugar Mill on the map.  The co-ordinates given by GHCN put it  in the middle of a cane paddock 600m to the south of Te Kowai Sugar Experiment Station, so that’s definitely it!  (If not, it’s identical in every other way!)  And that is the closest weather station to my home, so I became even more interested.

Te Kowai is an experimental farm for developing new varieties of sugar cane, run by scientists and technicians since 1889.  It has a temperature record of over 100 years with only a couple of gaps.  So in fact it’s an ideal rural station for referencing a nearby urban station, as it should have a similar climate.

Analysis

I plotted data from BOM for maxima and minima and obtained the means for Te Kowai, all Mackay city stations, all GHCN stations in our 5 x 5 grid, and several other towns and cities with long records (Te Kowai’s starts at 1908).   This is because “ In our analysis, we can only use stations with reasonably long, consistently measured time records.”

GISS combines GHCN data from all urban stations at the same location, and then homogenises this with data from neighbouring rural stations.  So I then plotted the same-location data and the post-homogenisation data.

A problem that appeared immediately is that the GISS annual mean runs from December to November, while BOM’s raw data is for calendar years.  Most of the time it matches pretty well, but there are several examples of poor quality data.  Another problem is that BOM does not compute a mean for any year with even one month of data missing, while GISS tolerates several missing months.

Here are graphs of the results.

First, BOM data for Mackay:

Mackay- composite of the Met Observation office from 1959, Mackay Airport, observations from the old Post Office, and a short Comparison  series.

Note:

  • The airport, on the outskirts of Mackay, is cooler by nearly 0.5 degree-  (More on this later).
  • You can see why they abandoned the PO after 1949!

As an aside, add in Te Kowai’s BOM figures to compare:

Note:

  • The airport’s temperature from 1999-2009 differs from Te Kowai’s by an average of 0.1 degrees warmer, whereas the Met Office is an average of 0.5 warmer than Te Kowai for the same period.
  • The PO tracks Te Kowai for a few years but about 0.25 degree warmer, then goes haywire.  Apart from the anomolous jump in the 1940s, the warmest year in both was 1931.

Surely GISS would have used Te Kowai data when analysing Mackay, wouldn’t you think?  As they say,

“The GHCN/USHCN/SCAR data are modified in two steps to obtain station data from which our tables, graphs, and maps are constructed. In step 1, if there are multiple records at a given location, these are combined into one record; in step 2, the urban and peri-urban (i.e., other than rural) stations are adjusted so that their long-term trend matches that of the mean of neighboring rural stations. Urban stations without nearby rural stations are dropped.”

Well, you’d be wrong.

This is what happened.  Step 1: the unadjusted GISS data:

Note:

  • The unadjusted data tracks BOM very closely, except it trusts the airport temperatures over the MO!  So far, so good.
  • They completely disregard the PO data.

Now, Step 2:  adjust with the mean of neighbouring rural stations

Note:

  • What’s going on?  The homogenised data starts out cooler and catches up.
  • The adjustment makes the slope of the adjusted data trend line STEEPER!   The trend increases from 0.9 to 1.2 degrees C over 58 years, or 2 degrees per 100years!
  • If they had included and adjusted PO data to the same trendline, 1908 would have been more than 1 degree cooler.

Here’s the plot of adjustments from the GHCN data:

Now let’s look at Te Kowai, in the country about 7km from Mackay.

Te Kowai/ Mackay Sugar Mill Station

  • Look how hot it was in the 1920s and 1930s!
  • Also note a steady increase of say half a degree from 1950-2008, and a linear trend of less then 0.2 degrees per 100 years.

Let’s look at what GISS does with this.

Note:

  • The unadjusted temperatures pretty well match the BOM data, except that like most rural stations GISS stops the record in 1992.
  • The linear trend of the unadjusted data slopes down, although the BOM data trends up again.
  • Temperatures were much higher in the 1920s and early 30s.  The hottest year was 1931.  (The hottest summer was 1922-23).  The next highest year after the 1930s was 1973.  Only in the last 10 years have temperatures approached (but not reached)  these levels.
  • Some would say it’s a “Travesty”.

But have a look at what they do next!  Here’s the graph of the homogenised data:

Note:

  • Wow- when they adjust, they don’t muck around!
  • Once again, the homogenised data is obviously different, showing much cooler temperatures in the first 40 years and higher at the end, with the result that the linear trend of the homogenised data slopes UP!
  • There is now a warming trend of nearly 1 degree per 100 years.
  • They have reduced the earlier warming but not eliminated it-1931 is still the hottest year.

Below is a graph of the adjustments GISS has made to the GHCN data.  Notice the step pyramid shape you’ve seen before at Darwin.  1908 is suddenly 0.9 degrees Celsius cooler.  The adjustments finally peter out to 0 in 1976.

Homogenisation adjustments to GHCN


So why didn’t GISS use the Te Kowai data to adjust the Mackay data, and make the Mackay trend less, not more?  After all, Mackay has an Urban Heat Island effect, whereas Te Kowai’s should be very small.  And why did they adjust the Te Kowai data at all, and so much?

Supposedly, they compare with nearby sites and make adjustments.  But what nearby sites?  To adjust Te Kowai, they must surely use only those with records from the early decades of the 1900s, like Clermont, Bowen, Charters Towers, Emerald, Barcaldine (too far away in my book).  These are small-ish towns from the same 5 x 5 grid area as Mackay, even though they have vastly different climates- much drier for a start.  Because they are “rural” GISS does not adjust their data at all.  The good thing is, I’m familiar with all of them.   I also looked at Ayr and Mt Morgan, “nearby” rural towns but outside the 5 x 5 grid, and Willis Island, out in the ocean.

Clermont (250km southwest) has a 0.8 increase/100years and  was warm in the 1920s-1930s.

Charters Towers  (328km north west)

0.7 degrees?  But note the jump (UHI effect?) in the 1980s and the step down with the change to the airport, so handle cautiously.  Also, warm years earlier.

Bowen (159 km north, on the coast)

Again note the big jump (UHI?) in the 1980s, and the big drop with the move to the airport.  Use cautiously.  Say 0.9 degrees per 100 years?  (Or flat if you join the beginning to the end of the airport data.)

Emerald (289 km south west)

0.8 degrees over 100 years?  Note the large step up (UHI effect?), after a declining trend, from the 1970s onwards, when the town boomed with expansion of irrigation, then coal mining.  Also note the warm period in the early 20th Century.  Airport data seems flat or lower.  Handle cautiously.

Ayr  (256km north west)

A huge jump of over one degree in early 1970s after a declining trend, so probably a change in surroundings- UHI, it’s a council depot after all- when compared with the DPI research farm just 6.3 km away.   Also, this is evidence that GISS did NOT combine all records at this location.  Not reliable.  If used, an increase of 1 degree over 80 years, or 1.2 degrees per 100 years.

Mt Morgan (Walter Hall) (304km south)

Many gaps.  A small decrease (1920s definitely hotter).

Barcaldine  (487km inland)

Far inland, Barcaldine has a continental climate.  Nearly 1 degree rise over 100 years, dropping lately.  Too far away to be seriously considered as “nearby”.

I also looked at Willis Island, far out in the Coral Sea, and only from 1923, but the nearest island site with a long record.

Willis Island (542km north east)

Flat as a tack.  BOM shows a very small rise.   Should be a good site for checking ENSO effects.

There are no other sites within 500km with a long record.

The mean of the warming trends of all land based rural stations excepting Te Kowai is 0.77 degree Celsius approximately per 100 years.  Leave out Mt Morgan it is 0.93.  With Te Kowai it is 0.7.

Conclusion:

First, an observation:

  • Two unexpected consequences of this study are I believe I have discovered an Urban Heat Island signal in small towns, and it seems airports are not necessarily warmer places.

So:  The GISS adjustments result in increasing the warming trend in Mackay, and introducing a non-existent warming at Te Kowai.  Te Kowai and Mackay both end up with warming trends of 1 degree and 2 degrees per century.  Now, GISS probably have a perfectly satisfactory algorithm which applies over most of the world, which averages the data of nearby stations to correct UHI effects in urban areas.  However, only ONE “neighbouring” station has a warming trend of over 1 degree per 100 years, and it has a noticeable UHI effect of its own and in my opinion shouldn’t be relied on, (and another high one is hundreds of km inland.)  All of the other nearby sites with long records have much less than 1 degree warming, and most have noticeable UHI effects.   Most, like Te Kowai, show a warm period in the early 20th Century.  The mean of the trends of all neighbouring long term stations (0.77 degree Celsius approximately per 100 years) does not warrant these adjustments. Even if they use the trend of the long term mean of the rural stations this is still only 0.9 degrees, and less than the homogenization adjustment for Te Kowai.  Further, the UHI of Mackay is corrected UPWARDS.

How can GISS justify their manipulation of the data, which they claim not to do?   How have they arrived  at the adjustments for Te Kowai and Mackay?  And besides, don’t they say that urban stations are adjusted by comparing with rural stations, not the other way around?  They don’t adjust any other rural stations that I’m aware of.

Here’s the explanation, and THIS IS THE SMOKING GUN-

They are allowed this manipulation simply because GHCN has declared at some stage “Mackay Sugar Mill Station” (Te Kowai) to be a  “small town”, with a population of 35,000.  Exactly the same population as Mackay.

Well, actually it’s surrounded by cane fields which have not changed much for the last 130 years, is about 7 km from Mackay and 2.5km from the nearest suburb (Ooralea).

There are 2 or 3 buildings around it for the manager, greenhouses, and laboratories, and its population on a good day might be… 10.

This has allowed them to adjust its data, when other rural sites are not adjusted.  It also allows them to NOT include the pre-1950 data from Te Kowai with the other rural stations, when adjusting Mackay’s data.

Why do I suspect this is deliberate?  Because the Te Kowai GHCN data ends in 1992, just like all the other rural stations in this area.   It was once classified as rural.

What would be the reason for this adjustment?  Who knows, but the effects are obvious:

  • Early warmer temperatures are artificially cooled.
  • These two stations now have an extra warming trend and now do their bit to support the warming trend at the other 2,300 stations worldwide.

And it’s happening in my own backyard!  I’m furious!

References 

http://data.giss.nasa.gov/gistemp/station_data/

http://www.bom.gov.au/climate/data/weather-data.shtml

http://www.bom.gov.au/other/disclaimer.shtml

http://www.bom.gov.au/other/copyright.shtml#acknowledgements 

http://www.appinsys.com/GlobalWarming/climap.aspx?area=australia

Breaking News! Ken Starts Blogging!

February 4, 2010

In a world’s first, Ken today commenced blogging in an effort to raise the bar of the blogosphere.

“Well, you’ve gotta start somewhere,” he said.

So far, this has not been picked up by any other blogs, media, in fact, anyone…

Hello world!

February 4, 2010

Welcome to WordPress.com. This is your first post. Edit or delete it and start blogging!