2002/2003 IfSAR data for Southern California: Digital Elevation Model (NAVD88)

Metadata also available as

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator:
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Publication_Date: 2004
Title:
2002/2003 IfSAR data for Southern California: Digital Elevation Model (NAVD88)
Publication_Information:
Publication_Place: Charleston, SC
Publisher: NOAA's Ocean Service (NOS), Coastal Services Center (CSC)
Online_Linkage: <http://www.csc.noaa.gov/ldart>

Description:
Abstract:
This metadata document describes the collection and processing of topographic elevation point data derived from Interferometric Synthetic Aperture Radar (IfSAR) measurement for coastal Southern California. Collection consists of topographic elevations from the California counties of Santa Barbara, Ventura, Los Angeles, Orange, and San Diego, and the hydrologic units within those counties that drain to the Pacific Ocean along with offshore islands within the Channel Islands. The resulting data include (1) Digital Elevation Model (DEM), (2) Raw magnitude radar reflectance data, and (3) Height Variance data. The data is first surface return (vegetation is in the dataset) X-band IfSAR with three meter point spacing and approximately one meter vertical accuracy in non-vegetated areas. The data is available in three vertical datums, NAVD88, GRS80 and NGVD29. This metadata record describes the DEM data in North American Vertical Datum of 1988 (NAVD88).
Purpose:
The mission of the NOAA Coastal Services Center is to provide coastal managers and partners with data and associated decision support tools to more effectively manage and preserve America's coastal zone. This project is a collaboration between the NOAA Coastal Services Center and the Southern California Water Research Project which is charged with contributing to the scientific understanding of linkages among human activities, natural events, and the health of the Southern California coastal environment. This project uses Interferometric synthetic aperture radar to create accurate, detailed elevation models and associated imagery to support an array of studies and analyses that include hydrologic modeling, watershed delineation and water quality assessment. When this data is combined with other geographic data layers, NOAA CSC and SCCWRP will have the ability to communicate an understanding of the linkages between natural and human activities to decision makers and other stakeholders, and to develop strategies for protecting the ocean environment for this and future generations.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20021020
Ending_Date: 20030706
Currentness_Reference: Ground Conditions

Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned

Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -118.00415
East_Bounding_Coordinate: -115.973179
North_Bounding_Coordinate: 33.631677
South_Bounding_Coordinate: 32.489551

Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: Elevation
Theme:
Theme_Keyword_Thesaurus: EDI Thesaurus
Theme_Keyword: Elevation
Theme_Keyword: Digital elevation model (DEM)
Theme_Keyword: Raw magnitude radar imagery (MAG)
Theme_Keyword: Height variance data
Theme_Keyword: DSM
Theme_Keyword: GeoSAR
Theme_Keyword: RADAR
Theme_Keyword: Mapping
Theme_Keyword: Bathymetry/Topography
Theme_Keyword: Interferometric Synthetic Aperture Radar (IfSAR)
Theme_Keyword: Interferometric
Place:
Place_Keyword_Thesaurus: Geographic Names Information System
Place_Keyword: United States of America (USA)
Place_Keyword: CA
Place_Keyword: California
Place_Keyword: Santa Barbara County
Place_Keyword: Ventura County
Place_Keyword: Los Angeles County
Place_Keyword: Orange county
Place_Keyword: San Diego County
Place_Keyword: Channel Islands
Place_Keyword: Coastal

Access_Constraints: None
Use_Constraints:
These data depict the heights at the time of the survey and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of it's limitations.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Department of Commmerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Contact_Position: CEM Project Scientist
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Ave.
City: Charleston
State_or_Province: South Carolina
Postal_Code: 29405-2413
Country: USA
Contact_Voice_Telephone: (843) 740-1200
Contact_Electronic_Mail_Address: tcm@csc.noaa.gov

Data_Set_Credit:
NOAA Coastal Services Center 2234 S. Hobson Ave. Charleston, SC 29405-2413 Tel. 843-740-1200 FAX. 843-740-1290 EarthData International of Maryland, LLC 7320 Executive Way Frederick, MD 21704 Tel. 301-948-9550 FAX. 301-963-2064
Native_Data_Set_Environment:
The following describes the hardware and software environment for the acquisition, processing/mosaicking and product finishing phases of the project. A. Acquisition 1. Gulfstream-II Jet Aircraft 2. Ashtech Z-12 GPS Receiver 3. Honeywell GPS/IMU (EGI) 4. Sandi National Laboratories Metrology System 5. Sony Data Instrumentation Recorder (DIR) 6. Sony 19mm tapes 7. GeoSAR X-band/P-band Collection - JPL developed software/hardware B. Processing/Mosaicking 1. SGI2400 Processors (a) DMF Ver. 2.7.0.0 (b) TMF Ver. 1.3.5.0 (c) Openvault Ver 1.4 (d) IRIX Ver. 6.5.12M 2. Ampex Storage (64 TB) 3. SGI Workstations (a) OS/UNIX (b) Erdas Imagine Ver. 8.5 (c) JURASSICPROK Jurx_20031024_cal (JPL) (d) DGX (JPL) (e) Multi-Mosaick, Ver 28 Jan 04 (JPL) (f) Multi-Match, Ver 28 Jan 04 (JPL) (g) Multi-Cull, Ver 28 Jan 04 (JPL) (h) Multi-Affine, Ver 28 Jan 04 (JPL) (i) Motion Measurement Processing, Ver 27 May 03 (JPL) (j) Terrasurver (k) Projector, Ver. .3a (l) ESRI ArcView 3.2a (m). EarthData Proprietary Software C. Product Finishing 1. Bentley - Microstation 2. Terrasolid - Terrascan Ver. 3.003 3. Terrasolid - Terramodeler Ver. 3.003 4. ESRI - ArcInfo ARC GIS Ver. 8.2 5. Microsoft Windows 2000 Ver. 5.0 6. EarthData proprietary software
Data_Quality_Information:
Logical_Consistency_Report:
EarthData International complied with the accuracy requirements through the placement of radar reflective corner reflectors, GPS ground control points, GPS base station locations and ABGPS/IMU. This data was integrated into the acquisition, processing/mosaicking and product finishing process to ensure that the accuracy requirements were met.
Completeness_Report:
The data set comprehensively includes all anticipated topographic elevation data for the region covered.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The horizontal accuracy was tested by comparing GPS ground control points against the data set. Test consisted of visual checks and the use of EarthData proprietary software. Reporting according to the National Standard for Spatial Data Accuracy, the accuracy statement is "Compiled to meet 4.3 meter horizontal accuracy at 95% confidence level."
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
The vertical accuracy value for the Southern California IfSAR survey is reported according to the vertical accuracy reporting standard published in the National Standard for Spatial Data Accuracy. The statement is "Tested 2.20 meter fundamental vertical accuracy at 95th percentile in mixed land covers." Thus, elevation values have been determined to be vertically accurate to within 2.20 meters. Compliance with the accuracy requirements was ensured by comparing National Geodetic Survey base stations within the study area to the processed elevation data set. The test consisted of subtracting interpolated (TIN) IfSAR elevation values from National Geodetic Survey (NGS) benchmark elevations. Differences between the two datasets were ranked and analyzed. The overall RMSE value was +/-1.04 meters based on a sample of 151 benchmarks. A Shapiro-Wilk statistical test indicated that the elevation differences were not normally distributed, so the vertical positional accuracy value was determined by calculating the elevation difference value at the 95th percentile of the total sample population following NSSDA guidelines.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: EarthData International, GeoSAR Mapping Services
Originator: EarthData International of Maryland, LLC
Publication_Date: 20040316
Publication_Time: Unknown
Title: GeoSAR Mapping of Southern California
Geospatial_Data_Presentation_Form: model
Publication_Information:
Publication_Place: Frederick, MD
Publisher: EarthData International of Maryland, LLC
Type_of_Source_Media: Digital data tape
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20040316
Source_Currentness_Reference: Publication Date
Source_Citation_Abbreviation: GeoSAR
Source_Contribution:
The project was flown using EarthData's modified Gulfstream-II jet aircraft. The IfSAR data was captured using a dual-frequency, dual-polarimetric, Interferometric airborne radar mapping system (GeoSAR) that generates digital elevation models (DEMs) and orthorectified radar reflectance maps near the tops of trees as well as beneath foliage. Data was captured simultaneously in both X-band (first surface, near the tops of trees) and P-band (beneath the foliage). X-band antenna are mounted under the wings close to the fuselage and have a 160 MHz bandwidth at a center frequency of 9.7 GHz. P-band antennas are mounted on the wingtips and have a center frequency of 350 MHz. Each X-band and P-band antenna provides two looks at each point on the ground for a total of four looks on each side. Flight lines are overlapped to provide coverage of the space directly beneath the aircraft. As a result, some points on the ground are covered eight times. Left-right look angles on each side of the aircraft combined with mosaicking process mitigates radar shadow and layover. X-band data has been processed for the entire project area and P-band has been processed for an area of approximately 300 square kilometers within the project area. Due to flight clearance requirements all data was normally collected between the hours of 10 PM and 7 AM.
Source_Information:
Source_Citation:
Citation_Information:
Originator: EarthData International
Originator: TerraSurv, LLC
Publication_Date: 2004
Publication_Time: Unknown
Title: Ground Control Survey
Geospatial_Data_Presentation_Form: model
Publication_Information:
Publication_Place: Frederick, MD, USA
Publisher: EarthData International of Maryland, LLC
Type_of_Source_Media: Paper/digital
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2004
Source_Currentness_Reference: Publication Date
Source_Citation_Abbreviation: GPS Ground Control
Source_Contribution:
Ground control and GPS base station locations were established to provide the necessary control to meet the accuracy requirements of the project. Radar reflective corner reflectors were deployed across the project area to be used in the mosaicking stage to ensue that the data met the accuracy requirements. A total of fourteen reflectors were deployed across the total project area with six reflectors deployed within the Phase I project area. A total of ten additional ground control points were established using GPS for vertical and horizontal coordinate values. These points were used during the quality control process to evaluate the accuracy of the final mosaicked data. Ground control references UTM Zone 11, NAD83, GRS80.
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Publication_Date: 2004
Title: 2002 Southern California IfSAR
Publication_Information:
Publication_Place: Charleston, South Carolina
Publisher: NOAA's Ocean Service (NOS), Coastal Services Center (CSC)
Online_Linkage: <http://www.csc.noaa.gov/ldart>
Type_of_Source_Media: Digital
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2004
Source_Currentness_Reference: upon processing
Source_Citation_Abbreviation: NOAA CSC
Source_Contribution:
NOAA Coastal Service Center obtained the final product deliverable from EarthData International, processed it, and loaded it into ArcSDE for distribution purposes.
Process_Step:
Process_Description:
EarthData has developed an in depth production process for processing GeoSAR data to meet NOAA's specifications. The following outlines the GeoSAR acquisition and processing workflow that was designed to produce the final product deliverables. 1. PROJECT PLANNING. The success of this project depended on effective management of all components of the project. To support this effort EarthData identified an experienced management team to oversee all aspects of the project. This team was responsible for ensuring that all project requirements outlined in the SOW and any subsequent amendments were met and that an open communication/reporting line was maintained with all participants. 2. GeoSAR ACQUISITION AND PROCESSING WORKFLOW. This section describes the general workflow for the GeoSAR system for the planning, collection, processing, and mosaicking of GeoSAR dual band IFSAR products. 2.1 Collection & Processing Requirements Production Steps Six major activities take place in this production step. A. Ground Control requirements are derived from the Project accuracy and QC specification in combination with the data take flight lines. The need for in situ corner reflectors, kinematic GPS profiles, and mosaicking control drive this task. B. Kinematic GPS is routinely specified for collection (where cost effective) to provide an independent means of quickly verifying the end mosaic product. This is an important part of the overall QA process, since this data is sequestered from the mosaicking staff until after the mosaic is completed. Kinematic GPS data is frequently collected prior to deployment in conjunction with the site survey (see item-D, below). C. GPS Base Station Location candidate sites are selected from the existing High Accuracy Regional Networks (HARN) in the project area, and the High Precision Geodetic Net (HPGN) in California. One or more such locations are usually occupied as the base stations during the flight mission. If such a station is not available within or close to the project site, then either an existing HPGN densification station is used or a new station is established through static GPS survey connected to HPGN stations and meeting the FGCS Order-C, Class-I relative positioning standard. D. Site Surveys are usually conducted several weeks to several months prior to deployment to identify reflector ground control locations, identify and resolve deployment issues (obtain permission or permits), and to verify that the GPS base station receives a high quality signal at the selected primary and backup locations. Kinematic dGPS traces are frequently obtained at this time using one of the base station locations. E. Detailed Acquisition Planning generates a complete acquisition plan including final notched frequency waveforms based upon coordination with the Army Spectrum Office. Flight lines are fully specified and the associated run-time data packets finalized and checked by the Project Manager and the Radar Operators for accuracy and completeness. F. Sortie Packing is the final planning step prior to initiating the Deployment & Acquisition of the raw radar data. In this step the various data take lines are bundled into a flight (sortie) and the corresponding logistical support requirements are determined (e.g., ground control, media, contingency supplies, etc.). The sortie schedule is specified, crews hired, personnel reserved, suppliers hired, and support material inventoried. 2.2 Deployment & Acquisition of Raw Data Production Steps Three major activities take place in this production step. A. Mobilization initiates the acquisition process. If the aircraft requires alternate basing, then it is moved to this base. The aircrew, the Radar operators, and the In-field Acquisition Manager secure local lodging and prepare for the initial sortie. The GPS base station and ground crews are deployed to the region, where upon they install the specified reflector ground control, check GPS equipment for proper operation, and secure local lodging. All supplies required to support the acquisition are propositioned. B. Sortie Generation consists of five basic steps, each requiring close coordination by the In-field Acquisition Manager. Some of these steps may not pertain to every sortie. a. Reflector Deployment-if not already in place, the specified corner reflectors are positioned and orientated per the sortie plan. b. Ground Station Deployment-the GPS ground crew deploy to their specified locations, install the monitoring equipment, and start collecting local GPS data at least 30 minutes prior to "wheels-up" and continue recording until notified of "wheels down". c. Preflight Logistics-sortie flight plan is filed, sortie supplies loaded, aircraft and radar equipment preflight checked, verify GPS ground crew in position. d. Data Takes-fly the specified plan. If problems arise, use best judgment to extract the maximum value from the sortie. e. Post Flight Logistics-notify GPS ground crew of landing, offload recorded data takes and auxiliary sensor data files and media, update operators' log, debrief In-field Acquisition Manager on mission, ship (as appropriate) data takes to production facility. This process is repeated for every sortie. Radar hardware failures and/or aircraft maintenance issues are resolved as quickly as possible and the sortie schedule is adjusted accordingly. C. Demobilization commences upon completion of the last sortie. All staff and aircraft return to home base. Post deployment inspection and maintenance are performed. 2.3 X-band and P-band Data Processing Production Steps Seven major activities take place in this production step. A. Data Take Ingestion is the process of incoming reception and logging of the data tapes and auxiliary data sent from the field into the production database. The base station GPS data is combined with the aircraft GPS data to create a dGPS location of the aircraft relative to the base station ground control point. This data is entered into the production database. B. Motion Measurement Processing (MMP) examines the auxiliary data for motion quality and prepares the parameters necessary for transferring the raw data off of the tapes. MMP is the beginning step of the Ground Processor. The motion data is sent through a QA process to verify its quality. The MMP inputs the dGPS aircraft position location data and combines it with the auxiliary antenna motion data to generate a Time Varying Parameter (TVP) file for the data take, which is used by the X-band and P-band processors to motion compensate the raw data. C. Tape Transfer is based upon data obtained from the MMP process, which identified what data is located where on the tape. The Tape transfer process requires 3 to 4 times real time to complete the transfer from the high-density Sony tapes into a format suitable for processing. D. X-band Swath Processing inputs operator or MMP specified parameters and outputs a coregistered X-band reflectance image and DEM at the specified ground sample distance. This is a computationally intense process, limited to about 4-quads/hour throughput. E. P-band Swath Processing inputs operator or MMP specified parameters and X-band DEM (or other suitable DEM) and outputs a coregistered P-band reflectance image and DEM at the specified ground sample distance. This is a computationally intense process, limited to about 2-quads/hour throughput. Steps 2, 3, and 4, while sequential, can be executing in parallel on different swaths. Up to a dozen different swaths may be in processing at single time. F. QC Swath occurs when the radar processors have completed their reduction of the raw data into reflectance and DEM swaths. This is a manual operation where each swath is examined for processing anomalies, such as phase-unwrapped regions, ambiguity jumps, of noisy data. Approximately 20% of this data will be reprocessed with different input parameters to mitigate the anomalies. G. Ready to Mosaic is the final QC check of the processed swaths to ensure that all the available data has been processed correctly and enough data is on hand to generate a composite mosaic for (a large portion of) the project area. 2.4 Wide Area Mosaicking Production Steps Three major activities take place in this production step. a. Segmentation-chop the swaths into segments containing usable, eliminating sub spec data (usually a result of severe motion artifacts due to turbulent weather during the data take). b. Swath De-Tilt-remove residual linear tilt in range for the swath (this is minimized by calibration, but might be required on wide swaths). c. Region Match Exclusion-mask out large water regions so they do not generate spurious interswath match points (this region is usually defined during the flight planning process). d. Control Point Extraction-using ground control information, extract the position of the radar corner reflectors to a fraction of a pixel. e. Swath Point Matching-in the overlap regions of any two swaths, find all reflectance (and/or DEM) points which correspond to the same point on the ground. This process generates hundreds to thousands of match points per swath-pair. f. Match Point Culling-severely cull the match points to retain only the very best, highly correlated points. B. Mosaic Affine Transformations is the process of combining the match points (produced by item-f above) and the ground control points in a weighted lease mean squared error swath-by-swath affine transformation for geographic registration to generate a composite mosaic of the region. Data from overlapping swaths are averaged in common areas and feathered at the boundaries. The same transformation parameters are applied for both the reflectance and height data. Null values in one swath are replaced by non-null values in overlapping swaths. Orthogonal tie lines provide powerful near range constraints to remove residual tilts. Ground control points remove residual systematic vertical bias (z-bump). C. QC and Mosaic Statistics are collected for the composite mosaic. Independent ground control is used to estimate the overall quality. Once the mosaic is declared completed by the mosaicking staff compare the kinematic GPS data values collected during acquisition against the mosaicked values to assess independently of the mosaicking statistics the overall quality of the final mosaic. If the mosaic is satisfactory, i.e., there are no major blunders, then optionally the kinematic data can be used as additional constraints to improve further the final product. If the result is not satisfactory, then the anomalies are noted and the composite mosaic is redone (usually from the swath point matching or from the affine transformation step. 2.5 Product Finishing and Packaging Steps. Seven major activities take place in this production step. A. Crop to Quads chops the composite mosaic into units suitable for ingestion by the DEM and Image editing workstation. B. Transfer data to product finishing team. C. DEM Edit is the manual process for removing residual radar artifacts from the DEM according to NOAA's specifications. D. Image Edit is cosmetic smoothing or removal of radar artifacts to enhance the photo-like quality of the imagery. E. QC is the final check on inherent data quality. Data, which fails to meet the delivery spec, is sent back to the processing team for remediation. F. Formatting established the data onto NOAA's specified media and formats. G. Delivery is the process of shipping the data to NOAA and following up that the data is found to be satisfactory. 3 DEM AND IMAGE CLEANING AND PRODUCT FINISHING The following provides an in depth description of the steps involved in this process. A Pre-Processing Data Review. Once the data acquisition and processing/mosaicking phase has been completed the data will be provided to the product development and finishing team to continue the processing and delivery development phase. B Data Preparation. Prior to beginning the processing and delivery development phase, all data will be processed into the workflow structure designed to support the delivery requirements. Data will be downloaded and placed into a folder or database. The downloaded data will then be transferred into a job folder where it will be extracted and cut into tiles roughly the size of a 7.5-minute quad. Automated data validation software routines will be run on the data to check for gross errors and anomalies. Once all of the data is validated it will be processed through an additional control check. A series of supplemental control points gathered during data acquisition will be utilized to provide an independent accuracy assessment and RMSE validation prior to beginning the final production phase. Once all of the data has been accepted, it is placed in a secure folder/database location to be used for the final processing and delivery development phase. C Image/DEM Edit The delivery development phase in broken into the Image edit and DEM edit phase. Each phase is made up of a series of steps designed to meet the delivery requirements outlined in the project SOW. The following provides an outline of the processes used to develop each set of deliverables. a. Image Edit. Our image edit process has been developed to meet the requirements for imagery deliverables outlined in the SOW. EarthData shall provide orthorectified radar reflectance imagery for the area of the main task order. (1) Imagery shall be in GeoTiff format and tiled with no compression to fit the 7.5-minute USGS quads. (2) Imagery shall have a horizontal resolution of 3 meters and a horizontal accuracy of 2.5 meters. (a) Translate to Tiff format. Data is withdrawn from the secure accepted database file location as needed and prepared for translation. EarthData utilizes proprietary software to coverts the existing Magnitude Image (or reflectance image) files to Tiff format. The converted data is visually viewed for completeness and prepared for the next step. (b) Merge tiles into final sheets. Based on the project limits EarthData will develop a tile structure that conforms to the limits of 7.5-minute USGS quads. This tile structure will be used as the template for merging tiles into the final sheets. To support this effort EarthData will utilize existing commercial off-the-shelf (COTS) and proprietary software to convert the Tiff format data into clipped and merged final 7.5-minute quad limits. The converted data is then reviewed for completeness and prepared for the next step. (c) Edit voids/PhotoShop. The GeoSAR preliminary flight planning and processing steps are intentionally robust to reduce and minimize the occurrence of void areas within the data. However, some limited void areas are typical for IFSAR-generated data. EarthData will utilize COTS and proprietary software to identify and fill identified voids. Each void will be individually reviewed and corrected during this process. At the end of this stage the base image product is complete and ready for input into the database. (d) Update index or database. A final QC of the data is performed on the completed data prior to input into the index or database. Based on acceptance, the final data is merged into the existing database structure. At this point the data is ready to start the next DEM edit phase of production. b DEM Edit. Our DEM edit process has been developed to ensure adherence to requirements outlined in the SOW. These include. (1) EarthData shall deliver DEM data in an ESRI floating point grid format with a 3.0-meter cell size. The data shall be split into tiles corresponding to USGS 7.5 minute quads. (2) Delivered reflective surface DEM data shall have a vertical accuracy of +/- 1.5 meter RMSEz or better. EarthData shall provide our "best effort" to meet vertical accuracy requirements within urban corridors (dense buildings of greater than 2-3 stories) due to shadowing and "layover" within these areas. (3) Elevation points used to generate the DEM shall have a horizontal resolution of 3 meters and a horizontal accuracy of 2.5 meters. (4) Data shall be delivered on DVD. (a) Digitize water polygons from Tiffs Based on the acceptance of the Tiff formatted data, EarthData technicians will interactively identify water polygons that require digitizing. All stream channels will be digitized for leveling if they exceed approximately twenty (20) meters in width. Open water bodies five (5) acres or larger will be digitized to level water in these areas. (b) Drape water polygons on DEMs. Using COTS and proprietary software the 2D collected water polygons are draped over generated DEMs. This process assigns each element with a "Z" value. (c) Fill water polygons with lowest elevation Using proprietary developed software the draped water polygons are imported and grids are dropped in to level to the lowest elevation within that polygon. A void map is generated for all edited voids. Color codes are used to identify void type, i.e. water, terrain. (d) Generate void polygons and fill. Using our proprietary developed software routines any remaining voids are identified and a polygon is generated around each void. Using the poly fill routine the software fills any remaining voids with an average of the surrounding data. A void map is generated for all edited voids. Color codes are used to identify void type, i.e. water, terrain. (e) Using TIN, Image and contours fix wells and spikes. During this step we generate a TIN and contours. Using the TIN and contours along with the magnitude image we identify and correct any wells, spikes and other anomalies. (f) Final Q/C of DEM using contours/TIN and Magnitude image An independent review of the data is conducted at this point to ensure that all wells, spikes and other anomalies were identified and corrected. This independent review is conducted by someone other than the technician who worked on that area. (g) Generate final DEM deliverable. Based on the acceptance of data from the final QC process the final DEM is generated. 4 DELIVERABLE GENERATION The Image edit and DEM edit phase prepare data for final deliverable generation. Based on final data acceptance, the data flowing from each phase will be formatted to an acceptable data delivery format and prepared for delivery. Final deliverables include. (1) Digital Elevation Model (DEM), (2) Raw Magnitude radar imagery (Mag). Supplemental data consists of (1) Height error layer (HEL), (2) Void mask, (3) Water mask, and (4) TIFF (8 bit raster of Magnitude imagery) Final deliverable formats consists of (1) DEM - ESRI Float Grid Format (2) Mag - IEEE 32 bit Float Format (3) Void Mask - ESRI Shape File Format (4) Water Mask - ESRI Shape FIle Format (5) Mag - 8 bit Raster TIFF Format 5 METADATA Project level metadata is provided for each phase of the project.
Source_Used_Citation_Abbreviation: GeoSAR
Source_Used_Citation_Abbreviation: GPS Ground Control
Process_Date: 2004
Source_Produced_Citation_Abbreviation: Topographic Elevation Mapping
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: EarthData International of Maryland, LLC
Contact_Address:
Address_Type: mailing and physical address
Address: 7320 Executive Way
City: Frederick
State_or_Province: MD
Postal_Code: 21704
Country: USA
Contact_Voice_Telephone: 301-948-8550
Contact_Facsimile_Telephone: 301-963-2064
Hours_of_Service: 9:00 AM - 5:00 PM (EST) Mon - Fri

Process_Step:
Process_Description:
In-house routines that used the GDAL open source library converted the floating point raster data sets into Environmental Research System Institute (ESRI) Arc Grids. These grids were then loaded into a single raster data set within ArcSDE using a utility developed with ESRI ArcObjects. Data was received in ellipsoid, and two other data sets (NAVD88 and NGVD29) were also created.
Source_Used_Citation_Abbreviation: NOAA CSC
Source_Used_Citation_Abbreviation: Topographic Elevation Mapping
Process_Date: 20070828
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Avenue
City: Charleston
State_or_Province: South Carolina
Postal_Code: 29405-2413
Country: USA
Contact_Voice_Telephone: (843) 740-1200
Contact_Electronic_Mail_Address: tcm@csc.noaa.gov

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid cell


Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 11
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: 117 degrees West
Latitude_of_Projection_Origin: 0
False_Easting: 500000 meters
False_Northing: 0 meters
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: Row and column
Coordinate_Representation:
Abscissa_Resolution: 3
Ordinate_Resolution: 3
Planar_Distance_Units: Meters
Geodetic_Model:
Horizontal_Datum_Name: Geodetic Reference System 1980 (GRS80)
Ellipsoid_Name: GRS80
Semi-major_Axis: 6378137.0 meters
Denominator_of_Flattening_Ratio: 298.257222101
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name: NAVD88
Altitude_Resolution: 0.01 meters
Altitude_Distance_Units: Meters
Altitude_Encoding_Method: Implicit coordinate

Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview: Elevation data
Entity_and_Attribute_Detail_Citation: none

Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Contact_Position: CEM Project Scientist
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Avenue
City: Charleston
State_or_Province: SC
Postal_Code: 29405-2413
Contact_Voice_Telephone: 843-740-1200
Contact_Electronic_Mail_Address: tcm@csc.noaa.gov
Resource_Description: Downloadable Data
Distribution_Liability:
Any conclusions drawn from analysis of this information are not the responsibility of NOAA, the Coastal Services Center or it's partners.
Custom_Order_Process:
This data can be obtained on-line at the following URL: <http://www.csc.noaa.gov/ldart>
Metadata_Reference_Information:
Metadata_Date: 20070828
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC)
Contact_Position: CEM Project Scientist
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Avenue
City: Charleston
State_or_Province: SC
Postal_Code: 29405-2413
Contact_Voice_Telephone: 843-740-1200
Contact_Electronic_Mail_Address: tcm@csc.noaa.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998

Generated by mp version 2.9.1 on Thu Sep 20 08:31:00 2007