Underwater Video and Still Ground Validation Imagery of the Florida Keys

This project is a cooperative effort between the NationalOcean Service, National Centers for Coastal Ocean Science, Center forCoastal Monitoring and Assessment, the state of Florida andAnalytical Laboratories of Hawaii, LLC. The goal of the work is to useNOAA-developed mapping methods to produce benthic habitat maps of southern Florida.The maps are generated by photo interpreting georeferenced IKONOS satellite imagery.These underwater video and still images are collected to perform ground validation ofseafloor habitat features during map preparation.

The National Ocean Service is conducting research todigitally map biotic resources and coordinate a long-term monitoringprogram that can detect and predict change in U.S. coral reefs, andtheir associated habitats and biological communities. The purpose ofthis survey was to investigate areas of imagery where uncertaintiesexist on the photo interpreter's behalf during the decision makingprocess of benthic habitat type for southern Florida.

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These data were prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Although all data have been used by NOAA, no warranty, expressed or implied, is made by NOAA as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by NOAA in the use of these data or related materials.

Contact NOAA for distribution options (see Distributor).; Links to the Underwater Video and Still Ground Validation Imagery are embedded in the Google Earth file -http://nosimagery.noaa.gov/images/ikonos/fl_keys_sampling_locations.kmzThe IKONOS satellite imagery used for benthic habitat mapping can be obtained in GeoTIFF format fromhttp://nosimagery.noaa.gov/images/ikonos/fl_keys_ikonos_noaa.kml;

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Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 1; ESRI ArcCatalog 9.0.0.535

The GPS points in this thematic data layer were acquired by GPS data using a Trimble GeoExplorer 3 with acustomized data dictionary designed to reflect the NOAA Classification Scheme for Benthic Habitats of the southern Florida.All habitat determinations were made in the field, recorded in the GPS data logger and seamlessly transferred to ArcView GISusing Trimble Path Finder Office Software. Attributes are all expected to be correct.

Point accuracy was determinedby three tests producing circular RMS statistic. Point GPS data wereacquired by repeated occupation of a fixed point yielding a 95% sigmaRMS of 5 meters compared to the position mean. Replicate GPSpositions were collected after navigating to a way point by boatyielding RMS value of 5 meters. Registered monuments were occupiedand replicate positions collected yielding an RMS value of 3 meters.Thus, all point features in these ground validation data are at least95% sigma of 5 meters.

Several hundred ground validation field positions wereoccupied and habitat characterization conducted for ground validationduring this work. These data were included in the dataset as a GISlayer and the first draft map was edited based on this ground truth.All areas where uncertainty existed on the part of thephoto interpreter during habitat delineation were investigated in thefield. All data were collected and integrated into the mappedproducts as planned.

The sites for collecting underwater video and still imagery for ground validation were selected to specificallyinvestigate habitat types and gradients of habitat spectral signatures and spatial extent. All areas where uncertaintyexisted on the part of the photo interpreter during habitat delineation were investigated in the field. Waypoints inthese habitats areas were generated on the georeferenced imagery using a GIS. The waypoints were then loaded into a GPS and,using a boat, were navigated to. Underwater video or still imagery and exact GPS positioning were obtained. For GPSpositioning, one hundred GPS positions were collected at one-second intervals. The 100 positions wereaveraged to obtain a single survey point. The data were post processed for differential correction. The general area wasexplored and, as needed, additional underwater or still imagery and GPS positions were collected to mark transitionsbetween habitat types of areas mapped at the level of the minimum mapping unit (MMU). These data are believed to be consistent.