Australian Tropical Cyclones: Data Availability

I work for the Australian Bureau of Meteorology on systems used to forecast Tropical Cyclones. It's great work, and I'm really enjoying both the technical side (lots of domain to learn) and the public service side (feels like I'm working on something that matters).

As a member of the Australian public, I am curious about what and exactly how much data is available regarding cyclone forecasts. For my own sake, I'm interested if one could write a script or build a little app to monitor Australian cyclones, provide information about them, and maybe provide an alert when a new cyclone "arrives" (is forecasted).

I started thinking about this during TC Yasi (Wikipedia link for Yasi) earlier this year. I came across some very interesting ad hoc community pages thrown together by enthusiasts. I thought that they could be providing more information on the cyclones that just a copy of the track map product.

I am going to use this blog post to explore public data that available (at least that I can find) for Tropical Cyclones and provide a few little scripts that may provoke some thought.

The Bureau's Current Tropical Cyclones page is a good place to start. It provides a map of Australia's area of responsibility and marks any current cyclones. Clicking a cyclone on the map takes one to the most prevalent warning for the cyclone (such as the track map or TC Advice). Below the map, Each current disturbance is listed along with the primary warnings associated with it. These warnings are also available from each states respective warnings page. There is a ton of information hidden away in this page on the science of tropical cyclones and the warnings provided. There are also spreadsheets that provide historical Australian cyclone information.

A much more interesting place to look is the anonymous FTP site for the Bureau. Specifically the directory ftp.bom.gov.au/anon/gen/fwo/ which contains the raw products used to provide a lot of information the Bureau's website. To map the product codes to a human readable warning or forecast name, use the product identification code listing page. Of particular interest are the machine readable CXML, GML and Shapefile TC products.

Most tropical cyclone warning products are partitioned first by tropical region (roughly by state: WA, QLD, NT), and then by the disturbance number in the region (3 in WA and QLD and 2 in NT). Using this breakdown, the following summarizes the interesting machine readable tropical cyclone products:

• Western Australia (WA)
• System 1: 
• GML/ShapeFile: IDW60266
• CXML: IDW60350
• System 2:
• GML/ShapeFile: IDW60267 
• CXML: IDW60351
• System 3:
• GML/ShapeFile: IDW60268 
• CXML: IDW60352
• Northern Territory (NT)
• System 1:
• GML/ShapeFile: IDD65401
• CXML: IDD65441
• System 2:
• GML/ShapeFile: IDD65402
• CXML: IDD65442
• Queensland (QLD)
• System 1:
• GML/ShapeFile: IDQ65248
• CXML: IDQ65255
• System 2:
• GML/ShapeFile: IDQ65249
• CXML: IDQ65256
• System 3:
• GML/ShapeFile: IDQ65250
• CXML: IDQ65257

I believe the GML and Shapefile products share the same filename, although the GML product has the .gml extension, where as the Shapefiles are zipped and provided with a .zip extension.

An additional interesting product is the three day cyclone outlook for each of the tropical regions:

• Western Australia: IDW10800
• Northern Territory: IDD10610
• Queensland: IDQ10810

I believe these product numbers are right, but I may have messed up a code or two. Also, I am not aware of the terms of service on these products regarding how or where they may be used or grantees of their consistency or continued generation. I do know that the content is copyright (creative commons), and the conditions for acknowledgement are clear.

Some small programs one could write using this data include:

• Summarize the likelihood of a cyclone each day for each of the three tropical regions
• Summarize the forecast tracks for current disturbances
• Visualize the forecast tracks for current disturbances
• Write an email notification problem when a new disturbance is forecast to effect a given region or area of interest.

I may write one or two of these myself. For example, I'd really like an application that sent me an email when a new (previously unseen) disturbance is forecast for the Australian tropical region, and maybe provide me with daily updates for all disturbances in the region. To tackle this app, one would have to write a script to monitor for the presence of specific products on the public FTP (such as the TC Advice products) for all regions, then parse machine readable products when available to provide details on the active disturbances. I might have a crack in coming weeks...

Cyclone image from Wikipedia.