Thursday, April 29, 2010
In the first versions of the JPEG2000 mosaics the infrared band (band 4) did not display properly in ArcMap 9.3.x. This is a known bug for certain versions of JPEG2000 headers. USDA has revised the header to allow proper display for most of the Virginia mosaics. VGIN has recently made the new versions (identified as Countyname.v6) on the VGIN download page. If you are using the old mosaics you may wish to update to the new version. If v6 is not appended to the county name only the uncorrected version is available at this time.
VGIN has also received from USDA the NAIP 2008 imagery in quarter quad tiles in GeoTIFF format. If you have a need for uncompressed imagery for specific areas feel free to contact John Scrivani for access to this public domain imagery.
An excellent example of the uses of leaf-on-infrared imagery is the Urban Tree Canopy Analysis being done for various communities by the Virginia Department of Forestry and the Virginia Geospatial Extension (VGEP) at Virginia Tech.
Tuesday, April 27, 2010
Though the plaques were commemorated last week, the effort to survey and improve the boundary definition was completed and adopted by both state legislatures in 1997. The Leesburg Today recently covered the story with an article.
The indefinite nature of the West Virginia - Virginia state line, which mostly follows ridge lines of the Blue Ridge Mountains, generally does not get highlighted until issues of development arise (see previous blog post about the windfarm controversy in Highland County, VA). When the issue does arise, surveying is required and is challenged by historical descriptions going back 150 years or more to the political processes that created the boundaries.
Wednesday, April 21, 2010
TFTN is important to Virginia GIS because it follows what we already have established, a "Transportation for Virginia" if you will, through the Virginia Road Centerline efforts. Thanks to data sourced from local governments who provide updated local transportation data to VGIN, who then combines the data statewide and includes VDOT data, Virginia has the most complete and comprehensive road network available in Virginia. These data are then leveraged with federal and private collaborators. An example of how the US Census is using Virginia RCL for the 2010 Census was demonstrated by this presentation from the US Census in slides 14-20.
Monday, April 12, 2010
VGIN has coordinated three projects this spring to collect LiDAR for over 3,233 sq miles of coastal Virginia according to the latest USGS National Map LiDAR specification (funding was provided by USGS, The Nature Conservancy and University of Virginia). The map shows these projects as well as some existing LiDAR data sets for coastal Virginia.
To help coordinate the development of better elevation data for Virginia, VGIN is forming an elevation working group, or Elevation Framework Initiative Action Team (FIAT). This group will:
- Conduct an inventory of existing elevation datasets
- Recommend elevation data standards and best practices
- Promote coordination and collaboration on the development of new elevation datasets
- Promote data sharing and incorporate elevation data in existing clearinghouses
If you are interested in serving on this working group please contact me, John Scrivani, on or before April 26th. To learn more about elevation efforts in Virginia you may want to look at my presentation to the VGIN Board from April 7th.
Tuesday, April 6, 2010
From the draft model:
The Geospatial Technology Competency Model (GTCM) is depicted in a pyramid graphic with nine tiers. This shape illustrates how occupational and industry competencies build on a foundation of personal effectiveness, academic, and workplace competencies. Each tier is comprised of one or more blocks representing the skills, knowledge, and abilities essential for successful performance in the industry or occupation represented by the model.
All interested parties are encouraged to submit feedback as this has the potential to eventually trickle down from the US Department of Labor into our Human Resource departments.