Philadelphia LiDAR 2018 - 2ft Contours


Identification_Information:
Citation:
Citation_Information:
Originator:City of Philadelphia
Publication_Date:2018
Title:
Philadelphia LiDAR 2018 - 2ft Contours
Geospatial_Data_Presentation_Form:vector digital data
Publication_Information:
Publication_Place:Philadelphia , PA
Publisher:Water Department - Information Systems and Technology
Other_Citation_Details:
03/01/2018 to 04/30/2018
Online_Linkage: http://www.pasda.psu.edu
Description:
Abstract:
Planimetric Coverage containing the delineation of topographic contours at two foot intervals.  Annotation of Contour Line elevations exists. LiDAR and LAS data was gathered for the City of Philadelphia in April 2018. DEMs were generated from the raw data. This dataset is lidar point cloud data covering the City of Philadelphia, PA, approximately 239 sq miles total. Each LAS file contains LiDAR point information, which has been calibrated, controlled, and classified. At the time of capture ground conditions were leaf-off, snow free, and water was at normal levels.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date:2018
Currentness_Reference:
publication date
Status:
Progress:Complete
Maintenance_and_Update_Frequency:As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -75.281560
East_Bounding_Coordinate: -74.955030
North_Bounding_Coordinate: 40.138940
South_Bounding_Coordinate: 39.871330
Keywords:
Theme:
Theme_Keyword_Thesaurus:ISO 19115 Topic Categories
Theme_Keyword:topography
Theme_Keyword:contours
Theme_Keyword:planimetric
Theme_Keyword:Elevation
Theme:
Theme_Keyword_Thesaurus:ISO 19115 Topic Categories
Theme_Keyword:elevation
Place:
Place_Keyword_Thesaurus:City of Philadelphia
Place_Keyword:Philadelphia
Access_Constraints:You must agree to the disclaimer and all other terms provided below prior to downloading City of Philadelphia GIS data.
Use_Constraints:
The City of Philadelphia makes no warranty or representation, expressed or implied, with respect to the quality, content, accuracy, completeness, currency, or non-infringement of proprietary rights, of any of the GIS or other data or information, or any other materials and items, that are displayed or made available for download from the Pennsylvania Spatial Data Access (PASDA) Internet site.  All such data, information, items and materials (collectively, the City GIS Data) are provided on an "as is" basis, and you are fully and solely responsible for your use of them and for any results or consequences of your use.  They have been created from a variety of sources, including sources beyond the control of the City of Philadelphia, and are subject to change without notice from the City of Philadelphia.  Users should be aware that the parcel dataset was created from the Philadelphia City Planning Commission's base maps and has not been updated since 1992.  To the extent you use, apply, add to, modify or implement this information in your own information system or other setting, or otherwise for your own purposes, you do so at your own risk.  In no event shall the City of Philadelphia or its agencies, officers, employees, agents, or representatives be liable for any damages of any kind or nature whatsoever arising from your downloading, modifying, sharing, distributing, or using of City GIS Data, including, but not limited to, direct, indirect, special, punitive, incidental, exemplary or consequential damages, even if notified of the possibility of such damages.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:Philadelphia Office of Innovation and Technology
Contact_Position:GIS Coordinator
Contact_Address:
Address_Type:mailing and physical address
Address:
1234 Market Street
City:Philadelphia
State_or_Province:PA
Postal_Code:19107
Country:US
Contact_Voice_Telephone:215-686-8101
Contact_Electronic_Mail_Address:brian.ivey@phila.gov
Hours_of_Service:8:00 am to 4:00 pm
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.1.1332
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Data_Quality_Information:
Attribute_Accuracy:
Logical_Consistency_Report:
Process	Data cover the entire area specified for this project. These raw LAS data files include all data points collected. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist. The raw point cloud is of good quality and data passes Fundamental Vertical Accuracy specifications. The specifications require that only Nonvegetated Vertical Accuracy (NVA) can be computed for raw lidar point cloud swath files. The vertical accuracy was tested with 10 independent surveys located in open terrain. The survey check points were distributed throughout the project. Specifications for this project require that the NVA be 19.6 cm or better AccuracyZ at 95 percent confidence level. 0.051 centimeters AccuracyZ at 95 percent Confidence Interval. The RMSEz was computed to be 0.1 meters. AccuracyZ has been compiled to meet 10 cm Fundamental Vertical Accuracy at 95 Percent confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines. Airborne GPS and IMU data were merged to develop a Smoothed Best Estimate (SBET) of the lidar system trajectory for each lift. Lidar ranging data were initially calibrated using previous best parameters for this instrument and aircraft. Using Optech LiDAR Mapping Suite 4.2 software, relative calibration was evaluated using advanced plane-matching analysis and parameter corrections were derived. This relative calibration was repeated iteratively until residual errors between overlapping swaths, across all project lifts, was reduced to 3 cm or less. Data were then block adjusted to match surveyed calibration control.

Lidar Post-Processing: After generation of the calibrated point cloud data in LAS format from Optech Lidar Mapping Suite (LMS), the data is imported into the TerraSolid software suite (running under Bentley MicroStation) for matching and classification. Upon import, the data is divided into tiles for the purpose of creating more manageable data. Once imported to TerraSolid, blocks of data containing overlapping flight lines are selected. The data in these blocks is analyzed by TerraMatch and adjustments to the roll, pitch, heading, and scale that minimize any data misalignment between the flight lines are computed. These adjustments are then applied to the entire mission's worth of data. Data across the mission is then manually reviewed to ensure proper alignment between flightlines has been achieved. This process is then repeated for each mission; once complete, intra-sortie alignment is verified.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Vertical_Positional_Accuracy:
Lineage:
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Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method:Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:String
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:Complete chain
Point_and_Vector_Object_Count:924266
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:Point
Point_and_Vector_Object_Count:196
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:Label point
Point_and_Vector_Object_Count:21288
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:Label point
Point_and_Vector_Object_Count:106238
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:Label point
Point_and_Vector_Object_Count:734
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution:0.000010
Longitude_Resolution:0.000010
Geographic_Coordinate_Units:Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name:North American Datum of 1983
Ellipsoid_Name:Geodetic Reference System 80
Semi-major_Axis:6378137.000000
Denominator_of_Flattening_Ratio:298.257222
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name:Philadelphia Vertical Datum - The Philadelphia datum was first established in 1600 by William Penn with a metal spike in the Delaware River pier at the foot of Chestnut St based on the mean height
Altitude_Resolution:0.01
Altitude_Distance_Units:feet
Altitude_Encoding_Method:Attribute Values
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Entity_and_Attribute_Information:
Overview_Description:
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:Pennsylvania Spatial Data Access (PASDA)
Contact_Address:
Address_Type:mailing address
Address:
Land and Water Building
City:University Park
State_or_Province:PA
Postal_Code:16802
Country:USA
Contact_Electronic_Mail_Address:pasda@psu.edu
Distribution_Liability:
The USER shall indemnify, save harmless, and, if requested, defend those parties involved with the development and distribution of this data, their officers, agents, and employees from and against any suits, claims, or actions for injury, death, or property damage arising out of the use of or any defect in the FILES or any accompanying documentation. Those parties involved with the development and distribution excluded any and all implied warranties, including warranties or merchantability and fitness for a particular purpose and makes no warranty or representation, either express or implied, with respect to the FILES or accompanying documentation, including its quality, performance, merchantability, or fitness for a particular purpose. The FILES and documentation are provided "as is" and the USER assumes the entire risk as to its quality and performance. Those parties involved with the development and distribution of this data will not be liable for any direct, indirect, special, incidental, or consequential damages arising out of the use or inability to use the FILES or any accompanying documentation.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name:Coverage or Shape-file
Transfer_Size:530.542
Fees:none
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Metadata_Reference_Information:
Metadata_Date:2018
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:Pennsylvania Spatial Data Access (PASDA)
Contact_Address:
Address_Type:mailing and physical address
Address:
115 Land and Water building
City:University Park
State_or_Province:Pennsylvania
Postal_Code:16802
Country:United States
Contact_Voice_Telephone:(814) 865 - 8792
Contact_Electronic_Mail_Address:pasda@psu.edu
Metadata_Standard_Name:FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version:FGDC-STD-001-1998
Metadata_Time_Convention:local time
Metadata_Extensions:
Online_Linkage:
Profile_Name:ESRI Metadata Profile
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