The Wacky World of Weather Stations: How To Check For Yourself

Monday 07/10/2019

Thanks to the Bureau of Meteorology’s very handy webpages, it is a fairly straightforward process to check how well their weather stations meet specifications set out in their Observation Specification 2013.1 “GUIDELINES FOR THE SITING AND EXPOSURE OF METEOROLOGICAL INSTRUMENTS AND OBSERVING FACILITIES” and  “Meteorological Observations and Reports Instrument Siting Requirements”    (2018).

It is a good idea to familiarize yourself with the specifications set out in these documents so you know what to look out for.

This is what I do.  I will use Sydney Observatory Hill as an example.

Go to the BOM Home Page.

Hold your mouse over the state of your choice, in this case NSW.

Select “All NSW Observations”.

Scroll through the forecast districts and stations.  In Sydney Metropolitan, click on your station (Sydney Observatory Hill).

This opens the latest 72 hours of  half hourly observations, which are interesting, but all you want is the Station ID Number: 066062.

Now open a new tab in your browser and go the BOM Home Page again.  Now scroll all the way to the bottom and click on “Climate Data Online”.

In CDO, at Option 1, click on the down arrow and select “Temperature”.

Now at Option 3 (Get the data), enter the station number (066062).

This immediately opens to daily maximum temperature, and that’s what we want: daily temperature records.  But I’m only interested in the Station details bar.

The station details bar tells you when the station opened, amongst other things, and at the extreme right is a tiny map of Australia with the word “Details”.  Click on the map.

This opens Site Information.  Scroll down to the bottom and click on basic site summary.

Voila!  This is a pdf document with Metadata about the site.  If you are lucky, the information will be up to date.

Scroll down several pages until you come to the site plans showing Instrument Location and Surrounding Features.  This is where you find how well the station complies with specifications.   Note the range ring sizes- this will help estimate distances on the plan.

There should be a little picture of a screen not too far from the centre of the range rings- that’s where the thermometers or temperature probes are housed.

There should be several pages of plans from previous inspections which reveal how the site has changed over time.

But now go back to the top of the pdf.   Note the Latitude and Longitude.  Copy these into your favourite mapping application (e.g Google Earth or Google Maps).  I usually enlarge the view to make it easy to copy.

Zoom in as much as possible in the satellite map to compare with the plan and see what else is nearby- often BOM plans leave out significant features like buildings, roads, runways, and the like.

Now list the good and the bad about the site- does it meet specifications?

I have bookmarked the important pages to save time.

(You could alternatively look at weather stations in your area of interest.  In that case, go to CDO Option 2 and enter the name of your town, then select the station you want from the list below.)

Have fun.

Tags: Acorn, adjustments, Australia, bom, temperature, weather