Hurricane Sandy and the Geographies of Flooding on Twitter

With the worst of Hurricane Sandy now past, we wanted to build on our initial map of references to "Frankenstorm" and construct a fuller picture of how the storm was represented and discussed on Twitter. The first alternative representation we offer visualizes how Twitter discussed the most obvious impact of the storm, the massive flooding (felt particularly acutely in New York City) that has not only disrupted the every functioning of the city, but also had likely long-lasting impacts on many individual lives and the way we prepare for and attempt to manage such 'natural' disasters.

To begin, we have been collecting tweets containing the terms "flood" and "flooding" in order to examine how Twitter usage might reflect lived experiences of the storm. By examining the digital data shadows of an intensely material event, we can hope to gain some understanding of how the intertwining and interfacing of virtual and material spaces apart from the immediate consequences of this particular event.

An interactive version of this map is available at:

http://oxfordinternetinstitute.github.com/InteractiveVis/usmap/

The map reveals a few important findings. First, like the map of references to Frankenstorm, tweets referencing flooding are almost exactly where you would expect them to be; in other words, the vast majority of tweets were located in the path of the hurricane. Nonetheless, it is interesting that so few people elsewhere in the US are tweeting about the unprecedented flooding and resulting damage taking place on the East Coast. In this sense, the geography of data shadows drawn from Twitter appear to be quite effective at reflecting experiences of the storm. The hurricane, in essence, leaves a digital trail.

Second, we are able to see that these data become significantly less useful if we want to draw insights at a scale finer than the county level. Until noon GMT on Tuesday, October 30th, there were only 5,209 geocoded tweets about flooding, a fairly small number over such a broad area. We even initially intended to map references in both English and Spanish to reflect the potential differences in experience between different linguistic groups affected by the storm, but despite the millions of Spanish-speakers undoubtedly affected, we were only able to collect five Spanish-language tweets!

In other words, it is the absences on this map that are almost more interesting than the mapped results. The lack of published content in Spanish means that we are necessarily only including published content from English speakers in these representations. The absences in the rest of the country are also revealing. Why are so few people in Kentucky, Missouri, Wisconsin, etc. tweeting about East Coast flooding? Is it because the act of tweeting about such an event is only really likely to be performed by people in situ, experiencing the storm? Are people outside the direct path of the hurricane interested in other impacts apart from flooding (for instance, the significant snowfall in parts of central Appalachia)? Are they interested at all? Or does the necessarily limited representation offered by Twitter constrain any possible explanations?