Friday, March 19, 2010

The Air Bases

Within the RCS Network, there are six air bases that are used to collect data. These are:
  1. 014932 - Tindal RAAF (NT)
  2. 040004 - Amberley RAAF (Qld)
  3. 061078 - Williamtown RAAF (NSW)
  4. 067105 - Richmond RAAF (NSW)
  5. 068072 - Nowra RAN (NSW)
  6. 087031 - Laverton RAAF (Vic)
The fact that military air bases are used as part of the RCS Network is important because, according to the BoM's website, preference has been given to stations with "a location in an area away from large urban centres".

In addition, the American NOAA/NCDC defines 5 classes of station quality ratings, as follows:
  • Class 1 (CRN1)- Flat and horizontal ground surrounded by a clear surface with a slope below 1/3 (<19deg). Grass/low vegetation ground cover <10 centimeters high. Sensors located at least 100 meters from artificial heating or reflecting surfaces, such as buildings, concrete surfaces, and parking lots. Far from large bodies of water, except if it is representative of the area, and then located at least 100 meters away. No shading when the sun elevation >3 degrees.
  • Class 2 (CRN2) - Same as Class 1 with the following differences. Surrounding Vegetation <25 centimeters. No artificial heating sources within 30m. No shading for a sun elevation >5deg.
  • Class 3 (CRN3) (error >=1C) - Same as Class 2, except no artificial heating sources within 10 meters.
  • Class 4 (CRN4) (error >= 2C) - Artificial heating sources <10 meters.

  • Class 5 (CRN5) (error >= 5C) - Temperature sensor located next to/above an artificial heating source, such a building, roof top, parking lot, or concrete surface.
Let's see how this first batch of stations measures up to the BoM's criteria and the CRN classification.

Tindal RAAF Base (1969)

The following two pictures provide different aspects of the station at the Tindal RAAF base. The first image is from the BoM website, and shows a typical rural setting for the weather station.


 


The second image is from Google Earth, which provides a birds-eye view of the general location. (The cross and numbers represents the co-ordinates of the station taken from the BoM site).


This image provides a vastly different aspect. As can be seen, the weather station is located adjacent to the runway and taxi-lane. Nothing in the BoM image indicates any of this environment. In fact, it provides a very misleading view of the situation of the station, IMHO.

Amberley RAAF Base (1941)

Again, we will compare and contrast the image provided by the BoM with the birds-eye view from Google Earth for this station. Again, the BoM image indicates that everything is fairly rural:




Meanwhile - check out the Google Earth view of the same location.


We see again that the station is adjacent to the runway and taxi-way of the airstrip. If we look at the top right of this image, we can also see the town of Ipswich (population ~155,000) encroaching on the air base.

Williamtown RAAF Base (1942)

Same drill for Williamtown RAAF base on the outskirts of Newcastle, NSW. BoM image:


Google Earth image:


Again, nothing in the BoM image that even hints at the close proximity of an airbase or runway.

Richmond RAAF Base (1993)

Same again for the Richmond RAAF base on the outskirts of Sydney. BoM image:


Followed by the Google Earth view:


Notice a pattern developing here?

Nowra RAN Base (2000)

BoM "rural view":


Google Earth "reality view".


Laverton RAAF Base (1941)

And for completeness, the Laverton RAAF base on the outskirts of Melbourne. First, the BoM "rural view":



Follwed by the Google Earth view:


As well as the nearby runway that we don't see in the BoM image, notice that a fair chunk of Melbourne also encroaches on the south-east.

Conckusion

This is quite a deceptive behaviour on the part of the BoM. A casual observer would be led to believe that the siting of these weather stations is fully compliant with both the internal BoM objectives, and the highest NOAA/NCDC classification (i.e. CRN1).

A more detailed examination indicates that nothing could be further from the truth. And of course Australia's "climate data" is sourced from these stations, amongst others.

The taxpayers that fund this should be outraged!

3 comments:

  1. Gday Eloi!
    You've saved me a lot of work- seems like we're on the same wavelength. I'm hoping to do similar checks here in Qld. Mackay RCS is particularly poor- surrounded by industrial sheds, roads, fuel tanks, sewage treatment plant, and an old rubbish dump.
    You have to be careful with BOM co-ordinates- they're not all that accurate I've found.
    Keep up the good work and see you at kenskingdom.wordpress.com sometime.
    Ken

    ReplyDelete
  2. @Ken
    Thanks. This started as an idea after reading the CSIRO+BoM work of fiction last week. The more I looked into it, the more staggered I was by just how poor some of these RCS station sites seem to be. I have a couple of your items noted that I intend to use when I get to those stations (e.g. Mt Isa).
    Eloi

    ReplyDelete
  3. Have you seen -

    http://chiefio.wordpress.com/2010/04/03/mysterious-marble-bar/

    ReplyDelete