Mapping Tornado Migration

John Nelson’s map of tornado migration in the United States, showing the seasonal variations in tornado occurrence, is a master class in data visualization and design—in deciding on the right way to present geographic information. The map combines three styles—impressionistic choropleth, weighted mean centre movement diagram, and small multiple—to present month-by-month information all at once; in the accompanying text (also here), Nelson discusses some of the alternatives he could have chosen instead. And in a separate post he talks about how he made the map. [Esri]

Previously: Mapping Tornado Tracks.

Online Map Updates

Yesterday’s updates to Apple Maps include four new Flyover cities, traffic data for Hong Kong and Mexico, public transit data for Los Angeles, and Nearby search for the Netherlands.

Google Earth Blog reports on the mid-January imagery update for Google Earth.

Google Earth Blog also reports that version 1.0 of ArcGIS Earth is now available. Announced last June and previously available as a series of public betas, ArcGIS Earth appears to be aimed at filling the gap left by Google when Google Earth Enterprise was discontinued last year.

Mont Blanc, the highest mountain in the Alps, is now in Street View.