A Quantitative Assessment of 2 and 4 feet Sea Level Riseon the Broward County, FL Landuse Using GIS Ugur Dagkilic Student Competition-Undergraduate Category URISA, 2010
About the author;Ugur Dagkilic holds a bachelor’s degree in Urban Planning andcertificates in Environmental Planning and GIS. For more than a decade,he worked in South Florida as a truss designer. This experienceprovided him the opportunity to experience some aspects of the civilengineering and construction industry.After realizing his interest in analysis using various tools, he gotenrolled in the Advanced GIS Certificate Program at Florida AtlanticUniversity in 2008 and will complete the program in May 2010. Besidesthe academic education, he has been self-studying and improving hisknowledge in the field using various sources.He can be reached;By email at firstname.lastname@example.org orBy phone at 954-643-6053
About the project;The project is the author’s first project after completing his coreGIS classes. After observing assorted sea level risedemonstrations on the media, he personally wanted to experienceit. A quantitative effect of the sea level rise on urban environmentin terms of numbers and landuse categories would be a goodexercise.Broward County, FL was a good project location due to its lowelevation, dataset availability and familiarity due to the authorsplace of residence.
(Source: www.noaa.gov)• Global warming and melting glaciers• Sea level has been rising 1-10 mm/year around the continental U.S., probably faster
• Low-lying coastal towns are in danger in the long term• Federal & Local Govt’s should make long term plans
How can I assessthe impact of sea level rise for the Broward County using GIS ? Florida State Broward County
Relevant DatasetsLIDAR for the Broward County NED for the Broward CountyBare earth or unfiltered, 5 ft res. 1/9 arc-second (approx 3m res)(http://gis.ihrc.fiu.edu) 1/3 arc-second (approx 10m res) 1 arc-second (approx 30m res) 1 m vertical resolution (http://seamless.usgs.gov)
Relevant DatasetsBroward County vector DOQQ tiles for the(polygon) type landuse Broward County(http://www.broward.org/ (www.labins.org)planningcouncil/gisdata.htm)
Sea Level Rise & Elevation 11.75 Elevation Data Brightness Scale (1 ft vertical resolution) 2 2 ft 1 1 ft 0 0 Level -0.72A math query on the elevation dataset using the raster calculatorwould provide the desired sea level rise effect
Methodology Project Workspace Project Goal Setup Elevation Data Land-use Data Data Collection In raster format In polygon format Conversion Dissolve and into feet Merge Determination of 2 and 4 feet Symbolization sea level Conversion into Conversion into Remain as raster Remain as polygon polygon raster Determine the Multiply the files Intersect the lands above 2 and 4 in raster calculator feet sea level polygons Option 1 (Vector op)Option 2 (Raster operation) is Quantify andused for this project Visualize the results Option 2 (Raster op)
Preparation• Create the job folder, geodatabase• Project the datasets into same spatialreference• Clip the datasets with the Broward Countyborder
Elevation Conversion • Need the elevation data in feet • LIDAR vertical resolution is already in feet • DEM vertical resolution is 1 m • 1m = 3.28 ft Raster Calculator Query : Elev * 3.2811.75 38.56-0.72 -2.37 Elevation in meter Elevation in feet
2 and 4 feet sea level determination Raster Calculator Query : Elev ≥ 2 Land above 2 feet water = 1 Land below 2 feet water = 0 Raster Calculator Query : Elev ≥ 4Both LIDAR and NED datasets arecalculated for comparison purposes Land above 4 feet water = 1 Land below 4 feet water = 0
NED provides meaningful regions Ex: A Ex: BNED provides meaningful regions. In South NEDFlorida, if a house on a block is under watermeans the whole block is under water LIDAR (Bare earth)
LIDAR provides better accuracy Ex: A Ex: BThere are areas that are covered by NED butnot covered by LIDARSimilarly; NEDThere are areas that are covered by LIDARbut not covered by NED LIDAR (Bare earth)
Which one to use; NED or LIDAR ? NED LIDAR Accuracy Good Better Easy to use Better Good Computer crashes Better Good due to the file size Meaningful Regions Better Good1/3 arc. sec. NED is used since it is easier to work with and it hasmeaningful uniform regions. The idea and calculations of the project isbased on these regions.However, LIDAR would be better if there was a custom script thatproduces water based regions similar to NED.
Conclusion..• Mainly high residential (especially high rise buildings)and conservation areas by the beach submerse with 2 feetsea rise.•Almost half of the county submerses with 4 feet sea risepointing out the degree of vulnerability of the county to 4feet elevation difference.•The precision of the results depends on a comprehensiveenvironmental analysis that uses the most up-to-date dataand employs various hydrologic analysis techniques.