Enhancing emergency communication with social media: Identifying hyperlocal social media users and information sources

Local social media users share and access critical information before, during, and after emergencies. However, existing methods can identify local social media users only after an emergency has occurred, and only then discover a small proportion of users sharing information in a geographic area. To address these limitations, we introduce the method of Social Triangulation to identify local social media users who access community information before an emergency in order to develop emergency communications strategies that contribute to community resilience. Social Triangulation identifies local users vis-a-vis the community organizations they curate within their social networks and, as a result, helps reveal the information infrastructure of a community. Consequently, social triangulation can inform emergency communications planning by identifying "filter bubbles" among social media users loosely embedded in an information infrastructure, as well as community influencers who are well-positioned to redistribute official information during an emergency.