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Do we need to encode location in news feeds?

There has been a great deal of discussion of late about the use of geotags – meaning the enccoding of location information within a web page or a news feed. Many proposals have been made for how to do this in RSS and Atom. See Geotags – the answer to everything? for earlier views of this blogger.

I would like to argue now that RSS, ATOM, and even web pages SHOULD NOT encode location information at all – the possible exception being the encoding of observations – otherwise the locations should be done ONLY by reference. Such a mechanism is simple, respects the notions of modularity and orthogonality in design, and allows web feeds to “stick to their knitting”.

I would propose that we have some sort of link mechanism like rdf:resource, the <a> in HTML or xlink:href as used in GML. In fact, all might be used (in different places). The link then references a geographic or geometric object and the source for that object is then a standardized server such as an OGC WFS (Web Feature Service). Processing the return is up to the data consumer and the range of choices is wide indeed.

One possibility is to have a glink tag with the syntax

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    <glink xlink:href="http://www.myobjects.org/obbjects#t11" mce_href="http://www.myobjects.org/obbjects#t11">content</glink>

Here the content is a word in the news feed or the web page.

It is up to the reader to de-reference the link and process the content returned by doing so. This could be to draw a map, create an animation, etc.

So this might look like:

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Hurricane Zeta is forming in the <glink xlink:href="http://www.myobjects.org/obbjects#t11" mce_href="http://www.myobjects.org/obbjects#t11">Gulf</glink> and its
<glink xlink:href="http://www.myobjects.org/obbjects#t11" mce_href="http://www.myobjects.org/obbjects#t11">track</glink> is such that landfall will be near
<glink xlink:href="http://www.myobjects.org/obbjects#t12" mce_href="http://www.myobjects.org/obbjects#t12">Corpus Christi</glink>.  
Zeta has already done a great deal of damage throughout a
<glink xlink:href="http://www.myobjects.org/obbjects#t13" mce_href="http://www.myobjects.org/obbjects#t13">wide area</glink>.

This approach allows a great deal of flexibility. Any word can be associated with a geographic context. Any sort of geographic context can be supported.

This seems much simpler than embedding information about Corpus Christi in dozens of web pages. There is only one Corpus Christi and only one track for hurricane Zeta.

What about observations? In the case of an observation – we take a “measurement” at some time and some location. The most obvious example would be that of taking a photograph. Again it would make sense to handle this the way images are handled in HTML. We don’t embed the image we reference it. So let’s not embed the observation let’s reference it also.