The South landscape unit (representing approximately the southern third of WCA1) was further divided into two zones (east and west, termed "Southeast" and "Southwest") based on marked changes in slope and aspect data generated from a DEM of the South landscape unit as a whole. Division of WCA1 into 4 zones reduces errors estimated by comparing DEM modeled water depths with those measured by EDEN Principal Investigators in the field. Subdivision of the South landscape unit into east and west zones resulted in lower error estimates for the Southeast zone without significantly affecting (i.e., improving or degrading) the quality of the Southwest zone - an area where DEM modeling is most challenging. To reduce artificial breaks in elevation along WCA1 subarea boundaries, models were overlapped by 1 cell at these boundaries and, for the North, Central and South zone boundaries, overlapping model values were averaged. For the boundaries between the Southwest and Southeast zones, cell values were "blended" based on weighted distance from the boundary edge. Finally, points along the North / Central and Central / South zone edges were subjectively selected and changed by adding or subtracting 0.03 meters (3 cm) to particular cells based on nearby cell values. This slightly reduces apparent artifacts without drastically affecting the integrity of the model. The EDEN offers a consistent and documented dataset that can be used to guide large-scale field operations, to integrate hydrologic and ecological responses, and to support biological and ecological assessments that measure ecosystem responses to the Comprehensive Everglades Restoration Plan. To produce historic and near-real time maps of water depths, the EDEN requires a system-wide DEM of the ground surface.
This file is intended specifically for use in the EDEN applications software. Therefore, it is a modification of the eden DEM released in January of 2010 (i.e., eden_em_ja10). The released January 2010 data was modified in two ways. First, elevation values have been converted from meters (m) to centimeters (cm). Second, data have been removed from the southern Big Cypress National Preserve and northwestern Everglades National Park area so that this DEM boundary matches the EDEN boundary still in use in EDEN applications software. Aside from this difference in horizontal units and area of coverage, the following data documentation applies.
To create a realistic region-wide elevation model for EDEN purposes, the elevation data were segregated by Water Conservation Areas and National Park boundaries so that local trends could be isolated, sub-region specific interpolation models could be developed, and realistic breaks in elevation along sub-region boundaries could be imbedded in a final, region-wide DEM.
For the previous release of the DEM, subarea DEMs were produced using the geostatistical approach called "anisotropic ordinary kriging". This version is composed of new models created for each new EDEN subarea in Water Conservation Area 1 (WCA1). For the latest iteration of the EDEN DEM "anisotropic universal kriging" was employed.
As with the previously released DEM, WCA1 surfaces were produced by removing all "upland" AHF points. However, in this version WCA1 "upland" was defined through a reclassification of the South Florida Water Management Vegetation Map rather than the Florida GAP map.
As the most challenging area from an elevation modeling standpoint, for this revision WCA1 was further subdivided into a total of 4 zones. First, boundaries between the North, Central and two South zones are based upon landscape units defined through the CERP Monitoring and Assessment Plan, Part 1 Figure 3-20 on p. 3-38 (p. 36 in the pdf file) at <http://www.evergladesplan.org/pm/recover/recover_docs/map/MAP_3.1_GE.pdf>. Then the South landscape unit (representing approximately the southern third of WCA1) was further divided into two zones (east and west, termed "Southeast" and"Southwest") based on marked changes in slope and aspect data that were generated from a DEM of the South landscape unit as a whole. Division of WCA1 into 4 zones reduces errors estimated by comparing DEM modeled water depths with those measured by EDEN Principal Investigators in the field. Subdivision of the South landscape unit into east and west zones resulted in lower error estimates for the Southeast zone without significantly affecting (i.e., improving or degrading) the quality of the Southwest zone - an area where DEM modeling is most challenging.
This file is intended specifically for use in the EDEN applications software. Therefore, it is a modification of the EDEN DEM released in January of 2010 (i.e., eden_em_ja10). The January 2010 released data was modified in two ways. First, elevation values have been converted from meters (m) to centimeters (cm). Second, data have been removed from the southern Big Cypress National Preserve and northwestern Everglades National Park area so that this DEM boundary matches the EDEN boundary still in use in EDEN applications software.
U.S. Department of the Interior, U.S. Geological Survey
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Generated by mp version 2.8.18 on Tue Feb 09 17:31:09 2010