Keywords
Theme:
Area of Primary Viewshed Concern - Mt. Vernon
Place:
Prince George Co. and Charles Co., MD
Description
Abstract
The Area of Primary Concern represents an area potentially visible from George Washington's Mount Vernon Estate (East Lawn), with the removal of forest cover and construction of buildings 36 feet high.
The original analysis was performed by EDAW, Inc. in 1991 using GIS visual simulation, and was adjusted in 2007 by Michael G. Clarke, AICP using ArcView and 1:24,000 USGS topographic maps, enhanced by National Geographic (TOPO series).
The accuracy of the Area of Primary Concern diminishes as the distance increases from Mt. Vernon. Field verification is required to confirm whether specific locations are within Mt. Vernon's viewshed.
Purpose
For use by Conservation Partnership Program of Mt. Vernon and Accokeek Foundation
_________________
Status of the data
Data is order-of-magnitude and requires further analysis
Data update frequency:
As needed
Time period for which the data is relevant
Date and time:
2008
Description:
publication date
Publication Information
Who created the data: Michael Clarke
Date and time:
February 20, 2008
Contact
Name:
Michael Clarke
Title:
Principal
Organization:
Michael G. Clarke
Phone:
518.523.8224
email:
clarke@hughes.net
Hours of Operation:
_________________
Constraints on accessing and using the data
Access constraints:
Permission required from Mt. Vernon Estate and Accokeek Foundation
Use constraints:
Incl. notation on limitations of data
Details about this document
Contents last updated: 20110715
at time 07251500
Who completed this document
Michael Clarke
Michael G. Clarke, AICP
REQUIRED: The mailing and/or physical address for the organization or individual.:
REQUIRED: The city of the address., REQUIRED: The state or province of the address. REQUIRED: The ZIP or other postal code of the address.
518.523.8224 (voice)
clarke@hughes.net
Standards used to create this document
Standard name: FGDC Content Standards for Digital Geospatial Metadata
Standard version: FGDC-STD-001-1998
Time convention used in this document: local time
Metadata profiles defining additonal information
ESRI Metadata Profile: http://www.esri.com/metadata/esriprof80.html
Horizontal coordinate system
Projected coordinate system name: NAD_1983_StatePlane_Maryland_FIPS_1900_Feet
Geographic coordinate system name: GCS_North_American_1983
Details
Map Projection Name: Lambert Conformal Conic
Standard Parallel: 38.300000
Standard Parallel: 39.450000
Longitude of Central Meridian: -77.000000
Latitude of Projection Origin: 37.666667
False Easting: 1312333.333333
False Northing: 0.000000
Planar Coordinate Information
Planar Distance Units: survey feet
Coordinate Encoding Method: coordinate pair
Coordinate Representation
Abscissa Resolution: 0.000256
Ordinate Resolution: 0.000256
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
Altitude System Definition
Resolution: 1.000000
Encoding Method: Explicit elevation coordinate included with horizontal coordinates
_________________
Bounding coordinates
Horizontal
In decimal degrees
West:
-77.194962
East:
-76.922118
North:
38.735502
South:
38.585336
In projected or local coordinates
Left: 1256720.542309
Right: 1334549.133485
Top: 389254.209638
Bottom: 334625.058355
_________________
Lineage
FGDC lineage
Process step 1
Process description: Dataset copied.
Source used: F:\All GIS Files\Mount Vernon\Mt. Vernon Analysis Layers\Monitoring Areas Parcel Analysis Series\20008 Viewshed 36'.No Veg.
Process step 2
Process description: Dataset moved.
Source used: F:\All GIS Files\Mount Vernon\Mt. Vernon Analysis Layers\Analysis Layers 2008\20008 Viewshed 36'.No Veg.
Process step 3
Process description: Dataset copied.
Source used: \\PPD-GELNER\C$\work\Working.gdb
Process date: 20100730
at time 06343800
Process step 4
Process description: Dataset copied.
Source used: Service=sde:Oracle11g:/;local=ppdsde; User=gis_reader; Version=ARCDBA.DEFAULT
Process date: 20101022
at time 10521600
Process step 5
Process description: Dataset copied.
Source used: Service=sde:Oracle11g:/;local=arcsde; User=gis_reader; Version=ARCDBA.DEFAULT
Process date: 20110705
at time 11174200
Process step 6
Process description: Dataset copied.
Source used: \\PPD-GELNERR\C$\Work\SDE_Archive.gdb
Process date: 20110705
at time 13113400
Process step 7
Process description: Metadata imported.
Source used: C:\Documents and Settings\Robert.Gelner\Desktop\metadata.xml
Process date: 20110705
at time 13142300
Process step 8
Process description: Dataset copied.
Source used: \\PPD-GELNERR\C$\Work\Working.gdb
Process date: 20110706
at time 06443500
ESRI geoprocessing history
1. Process
Date and time:
20100727
at time 150107
Tool location:
C:\Program Files\ArcGIS\ArcToolbox\Toolboxes\Conversion Tools.tbx\FeatureClassToFeatureClass
Command issued
FeatureClassToFeatureClass C:\work\Primary_Viewshed.shp C:\work\Working.gdb\SDE_Prep Mt_Vernon_Viewshed_Poly # "Id 'Id' true true false 6 Long 0 6 ,First,#,C:\work\Primary_Viewshed.shp,Id,-1,-1" # C:\work\Working.gdb\SDE_Prep\Mt_Vernon_Viewshed_Poly
_________________
Spatial data quality
Horizontal positional accuracy
Accuracy diminishies with increased distance from Mt. Vernon. Area of primary concern represents potential viewshed from East Lawn of Mt. Vernon, assuming removal of vegetation and construction of 36' high buildings. Field assessments will be required to confirm extent to which any particular location would be within Mt. Vernon's viewshed.
_________________
Spatial data description
Vector data information
ESRI description
ARCDBA.Mt_Vernon_Viewshed_Poly
ESRI feature type: Simple
Geometry type: Polygon
Topology: FALSE
Feature count: 11
Spatial Index: TRUE
Linear referencing: FALSE
SDTS description
Feature class: SDTS feature type, feature count
ARCDBA.Mt_Vernon_Viewshed_Poly:
G-polygon, 11