Trulia Hindsight
This is a fun find.
I happened across a tool, Trulia Hindsight, that animates population (housing) growth over time on top of satellite imagry. The tool is a “side-show gimmick” for a real estate search site but, it’s pretty cool anyway.
It’s interesting to see some of the population trends that you’ve always heard about. For example, I’ve always heard that my town was mainly farmland until the 50’s; my neighborhood was a late 50’s development and; that the little lake near my house was a 20’s tourist (camp) destination. You can actually see those facts with Trulia. You can zoom in and out and the data gets finer/coarser corresponding to zoom level. Zoomed out, you can see broader trends like the city growth around the turn of the century, growth around rail lines and, the more “spattered” growth that having a car that can take you anywhere created.
I’m not sure how clean the data are. You see some pretty big bumps, for instance, at 1900. Is that just a book keeping artifact and lots of pre-1900 stuff gets “recognized” for the first time in that year or is the data real and the bump shows the impact of absorbing lots of immigrants? Regardless, it’s a fun data visualization.
That is very cool. I wish they could show the development of the roads over time too! The archive of satellite shots from the mid 1800’s is pretty thin, eh? ; )