Sea Level Rise in the Gulf Coast States

Background Information

Sea level rise his become an issue of concern associated with the topic of global warming and climate change.  The world's largest cities are located along coastal areas; hubs for international travel, shipping, and industry.  This study focuses on examining the number of people affected by various levels of sea level rise in states located along the Gulf of Mexico.

Data Sets

• Population Data: Census Tracts
• Sea Level Rise Data, CRESIS

Methodology

Census tract data was clipped down to the spatial extent of the Gulf states (Texas, Louisiana, Mississippi, Alabama, and Florida) using ArcGIS 10.1.  To insure accurate population values, the population density of each census tract was calculated.  Using the downloaded sea level rise file, the gulf states shapefiles were trimmed down to three files containing the spatial extent of  one, three, and six meter sea level rise.  Using field geometry, I calculated the adjusted area of  each census tract that is affected by each level of sea level rise.  To obtain the population affected per census track, the newly calculated area was multiplied by the original population density using the Field Calculator.  To acquire the total number of people affected by one, three, and six meter sea level rise per state, summary statistics were run on each file.  The sum of the adjust ed population field was calculated, and the state was used as a case field to separate the calculations by state.  The calculated populations affected per state where then exported and uploaded in ArcGIS for plotting.

Conclusions

This study found that an increase in sea level yields a positive increase in the number of people affected.  Due to its low elevation and higher area of coast line, more people are affected by sea level rise in Florida than the other four states. Florida displays the greatest disparity between a three and six meter rise in sea level, most likely do to its overall low elevation. Louisiana is the second most affected followed by Texas, Mississippi, and Alabama.

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