One of the great things about the combination of maps, geo, location and London is that roughly once a month there's some kind of meetup happening in the city on these themes. One of the longer running players in this space is the Geospatial Specialist Group of the British Computer Society which is being relaunched and reinvigorated as the Location Information SG. Earlier this week I gave a talk, but what to talk about?

It didn't take too long to come up with a suitable theme. In my current day job, consulting with open data specialists Lokku, I come across the benefits and the challenges in using open data on almost a daily basis. One of the earliest lessons is that nothing is simple and nothing is straightforwards when you bring licensing into a field and open data is no exception.

My morning's reading today has been dominated by a map image that the UK's Environment Agency released on December 6th that, to quote the Tweet, shows "the extent of potential flooding of London if the Thames Barrier wasn't in place". If you know London at all, it's certainly an arresting image but like so many times when I encounter a map, I want to interact with it, move it, see whether where I live in London would have been impacted. So I started investigating.

Some background context is probably in order. On December 5th. the UK's Met Office issued severe weather warnings for the East Coast of England. A combination of a storm in the Atlantic to the north of Scotland, low atmospheric pressure and high tides were all combining to push a massive swell of water through the narrows of English Channel, in effect squeezing the water through the Dover Strait. As the North Sea and English Channel are relatively shallow, the sea would back up and had the potential to flood large areas of the East Coast of England as well as the areas surrounding the tidal stretch of the River Thames and that means London and possibly even where I live in Teddington, which marks the upper limit of the tidal Thames. Thankfully for those of us who live West of Woolwich, the Thames Barrier exists to protect London from such flooding, though I'm sure this is less of a comfort to those people who live to the East of the barrier.

Back in December of 2009, I wrote about Paul Clarke trying to solve the problem of where's my train; that there must be a definitive, raw source of real-time (train) information and that

I assert that train operators know where their assets are; it would be irresponsible if they didn't

Whilst the plethora of train operators that fragmented from the ashes of the old British Rail network haven't answered this challenge yet, Transport for London has, opening up just such data as part of the London Datastore API. In today's age of talented web mashup developers, if you release an API people will build things with it if the information is useful and interesting and that's just what Matthew Somerville of MySociety did at the recent Science Hack Day ... a (near) realtime map of the London Underground showing the movement of trains of all of the Tube lines. A screen grab wouldn't do it justice and it takes a while to load, so a video grab might help here.

A product launch from Google is accompanied by a massive media campaign that reaches far beyond the techy demographic; Google is a consumer brand these days and their messaging generates headlines in both traditional and new media. This is a good thing; right?

It's certainly high profile messaging, Ted Dziuba writing in the UK based Register with less than his usual profanity laden prose, first brought the term Googasm to my attention and the recent launch of Google Latitude certainly has all the hallmarks of Googasm, but this has rapidly turned into an inverse Googasm of shrill, rhetoric laden, fin de siecle doom with the BBC commencing and London's Metro newspaper going way overboard.

• Spy in your pocket?
• Google spying on workers?
• People covertly tracking you after leaving your phone in a bar?
• Suspicous partners tracking their loved ones?