Web Cartography and the Dissemination of Cartographic Information about Coastal Inundation and Sea Level Rise

This chapter examines the Web cartography used in the United States to help citizens and local officials plan for storm surge and sea level rise — coastal hazards conveniently describedby hypothetical supplementary shorelines. Storm surge is addressed principally by federal flood-insurance maps, now available over the Internet but severely encumbered by a 1970s strategy requiring a huge number of large-scale paper map sheets. In addition, some states and localities address storm surge with storm evacuation maps, typically at a smaller scale that makes Web distribution more straightforward. Dynamic graphics, though not common, provide dramatic illustrations of plausible local impacts of coastal flooding. By contrast, coverage of sea level rise is not only biased toward scientists and policy makers interested in climate change or wetlands preservation but also marked by a heavy reliance on related text and graphics to communicate uncertainty and impact. Important maps embedded in PDF files are not easily located by search engines in image-mode, and a set of spatially detailed but politically sensitive maps made available online to confidential reviewers has not been released to the public. Anecdotal evidence suggests that the United States is more proactive than Britain, Bangladesh, and other coastal nations in using Web cartography to promote geographic knowledge of their coastal hazards.