Monday, November 16, 2009

This is a special blog for National Geographic's Geography Awareness Week. It is brought to you by James Cook University (I wrote it at work).
I am the Cartographer at James Cook University, where the most common request always starts with “I need a map of”. Then there will be a long list of parameters, or perhaps just one or two, but what the person requesting the map is always surprised to find out, is that such a map doesn’t exist, or if it does exist, it is for a much smaller scale than they imagined.
Large scale mapping, a useful scale that you would use in the field like 1:50,000 (a map sheet being about 26x26 square kilometres, or 676 sq. kms) is still only available for the coastal and built-up areas of Australia. This scale is topographic mapping, with very little thematic mapping done.
The issues are cost and effort. To get the information together to make a map takes a very skilled group a very long time, and so this sort of effort is only made rarely, for something really important.
Lucky for me there has been a really big effort going on for over 12 years in the Wet Tropics Management Authority. They are a Government Agency charged with the management of Australia’s World Heritage rainforests, which cover almost 900,000 ha of land, mostly National Parks, between Townsville and Cooktown, north Queensland. Why does that make me lucky? Because after all those years getting the information right, they asked for my help to make it into maps, real maps that are published on paper.
You see, the problem with a big data gathering effort is that you can gather so much data that it becomes really difficult to map. So while I had access to this data for my researchers, if they wanted me to make a map of it, visualise so they could see it, hold it and understand it, I always had to do so for each person individually. Everyone wanted to see something different, or specific combinations of data that were of interest to them alone. So using the same data, I would make something new of it again and again.
Since I understood the dataset so well it was a bit easier to develop a cartographic model that would show an overview of the data while providing the full detail of every single polygon down to one mm in size. I wanted it to work like Google Maps, zooming in with your brain and the information provided in the legend, instead of using their interactive programming.
Soon the mapping project will be finished and launched. It took us another two years to finish all the maps. There are 52 maps needed to cover the Wet Tropics Bioregion. We have had 30 of them published on waterproof paper, the full set will be available on DVD or to download from the web.
I think they are very beautiful, as well as very useful. Good cartography should be lovely to look at. I chose to use colour families that you could recognise (broadly) by looking at the map.
The detail is in the alphanumeric identifier on each little polygon. Flip the map over and you can read the whole story of what lies within it.

So far everyone who has used the maps finds them really easy to navigate. I think it is a good example of the expectation of rich information that you get from data in a GIS (Geographic Information System) finding its way onto a paper map with no loss of detail.

And how detailed is it? There are over 90,000 polygons describing over 200 vegetation types. The GIS team at WTMA calculated that all the polygon arcs they digitized would reach ¼ of the way to the moon.

I hope the maps will be available early in 2010. Visit the Wet Tropics web site at http://www.wettropics.gov.au and find out more about our amazing World Heritage rainforests, and hopefully download one of the maps. I think they are a joy to behold!

2 comments:

Bluenoser said...

I hate boats. But I love maps. I like the way you've done that with being able to flip the map and identify the veg.

They are very pretty maps. The colours... Nice to look at Dee.

-B

Dee said...

I am really proud of them, they are my best work ever.