The National Map: Quad Sheet Factory

Mark DeMulder of USGS briefed NSGIC on The National Map this week. He started with why the program exists, citing three basic reasons:

- serves info to decision makers
- supports our science mission of USGS too
- cross-jurisdictional maps are useful in emergencies

He then moved on to what The National Map got from the Stimulus Bill. Right now, it looks like the program will receive $15 million to add to its typical $60 million budget.

He went on to focus on basically one use of The National Map that’ll start showing itself in the coming months: electronic topo quads.

The National Map will be the source for the new electronics topos. He didn’t make this point, but I will: While many of us think of The National Map as a “portal for data,” it’s more than that. In this case its the “shop floor” for producing a key product for USGS customers. It’s other things, too, and I hope USGS wills start positioning it as serving many functions. I think that story got lost when many of us were disappointed in its early online presence.

These e-topos are now being produced in sync with the three year National Agricultural Imagery Program (NAIPs) data capture cycle. So, about 1/3 of the topos will be created each year. For 2009 the number is 15,250, a little less than a third. The process is almost entirely automated, with each topo taking a little less than an hour to produce. The human contributions include reviews of transportation data and “name conflict issues,” aka labeling issues. The topos are delivered in GeoPDF (TerraGo) format which DeMulder was clear is an unpublished proprietary format read by specific proprietary software. These maps will be available in the USGS store within the next few weeks.

The questions about the presentation were, in NSGIC tradition, pointed and valuable. I paraphrase them here:

Q: The area of interest is always at the corner of four quads. Is that still true with e-topos.
A: Initially, yes, it’s still same grid. In the long term, perhaps in the enxt fiscal year, the user may be able to set the coordinate of the center of a custom, on-demand, quad.

Q: Must you use leaf on imagery (NAIP) for wooded states like NY? Can you use the leaf off imagery that USGS hosts for the state of New York?
A: For now, for simplicity, each quad will have NAIP imagery (leaf on). But, the long term intent is to use the “best data” we can.

Q: This project organized over map sheets, when we are trying to create and use seamless datasets.
A: The data is only gridded when put into the quad product. The underlying databases are seamless and sometimes based on other geographic organizing principles (NAIP is gridded by quarter quad, hydro data by watershed, for example.)

Q: How do we help get our state data to be part of The National Map? This focus on quads suggests The National Map is not thinking of its partners (the states’) needs.
A: This is but one activity for which USGS is using The National Map. The states and their needs are also a priority.

Q: Who are the users of these quads? We don’t see them in our state offices.
A: Among others, NORTHCOMM, Northern Command of the Army.

Q: What’s up with the proprietary format for these quads? That’s a bad idea!
A: TerraGo is taking GeoPDF through the OGC standards process, so it will likely be an open standard. The reader is available on all platforms. [I guess he meant PDF readers. The TerraGo website says its products, including the optional GeoPDF Toolbar (link to this download on USGS store MapLocator is broken!) are only available on Windows. “Currently TerraGo solutions are Microsoft® Windows®-based applications”] Remember, GeoPDF is a product, USGS provides Web services using open standards.

Q: What’s up with this LiDAR standard? [Mentioned in a previous briefing with the suggestion few were consulted in its development.]
A: We will leverage state and fed partners for LiDAR. I’m not aware of the LiDAR standard discussions, but it’s in our best interest to engage community.

Q: What up with USGS and CubeWerx [Canadian company that provides OGC compliant server software]? There’s a compatibility problem with ESRI products.
A: Don’t know - but WFS is used to publish web services. ESRI is a long time member of OGC.

Published Wednesday, February 25th, 2009

Written by Adena Schutzberg

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