Create land ownership stats

[shawnbot]

We need per-state county maps that also show federally owned and Native American ("Indian") lands. Along the way we'll need to generate data that gives us the land area and ownership percentages of state and national land (we can check our numbers against this paper by the Federation of American Scientists). State maps should include as individually addressable (and style-able) layers, from bottom to top:

1. State polygons (ideally, cropped to the area around each state)
2. County polygons (as-is)
3. Land ownership polygons (or raster, barring overly complex shapes)
4. County boundaries (line mesh)
5. State boundaries (line mesh)

Ownership percentage stats should be rolled up into YAML that looks something like:

XX: # e.g. 'CA'
  area: 10000
  federal:
    total: 20000
    BLM: 12000
    NPS: 5000
    # etc.
  indian: 4000

I'm really liking the idea of using static SVG for the maps and coloring counties dynamically. Eventually, I'd love to replace the <eiti-map> component (which loads the TopoJSON, projects the data, and creates SVG on the fly) with one that loads SVG and leverages the <use> element to fill shapes, as in this pen. This should load and render much more quickly, even if the resulting SVG documents are larger than the TopoJSON, because the duplicate topology arcs will be compressed en route to the browser. It'll also result in less repetition in the page templates.

The result of this should be one SVG file per state, e.g. maps/states/UT.svg for Utah.

The best data probably comes from the National Atlas:

• Federal Lands

  [...] lands owned or administered by the Federal Government, including the Bureau of Land Management, the Bureau of Reclamation, the U.S. Department of Agriculture Forest Service, the Department of Defense, the U.S. Fish and Wildlife Service, the National Park Service, the Tennessee Valley Authority, and other agencies. Only areas of 640 acres or more are included. Descriptive information includes the name and type of the Federal land and the administering agency. There may be private inholdings within the boundaries of the Federal lands in this map layer.

• Indian Lands

  Indian lands are areas with boundaries established by treaty, statute, and (or) executive or court order, recognized by the Federal Government as territory in which American Indian tribes have primary governmental authority. The Bureau of Indian Affairs is responsible for the administration and management of 55.7 million acres of land held in trust by the United States for American Indians, Indian tribes, and Alaska Natives, and maintains a list of the 562 Federally recognized tribal governments.

• Protraction and Leasing (offshore areas)

  Official Protraction Diagram and Leasing Map boundaries cover areas of the outer continental shelf within Federal jurisdiction. They are generated by the Minerals Management Service (MMS) in accordance with 30 Code of Federal Regulations (CFR) 256.8. Leasing Maps are irregularly shaped areas, developed early in the MMS offshore minerals management program, for near-shore areas in the Gulf of Mexico. Official Protraction Diagrams cover the remainder of the area included in the MMS offshore minerals management program.

[shawnbot]

Okay, so as of 2c86b93 we have state and county maps that show federal land ownership. Adding Indian lands to this should be technically easy, but now we have a serious design challenge on our hands, because these maps are going to get hard to read pretty quickly, e.g.

@gemfarmer and I have made lots of headway in getting these maps incorporated into the new state pages, and adding the rest shouldn't be too difficult. The page linked above exists as a stress test of sorts, and in its current state even Chrome fails in it sometimes (some maps randomly don't load one or more "layers", for instance), so this approach might not be bulletproof. But I think that if we keep the number of maps on a single page as low as possible and minimize the number of layers on them, then this could work.

Next up is to figure out how to make these maps legible, IMO. What do you think, @ericronne?

[ericronne]

@shawnbot (and perhaps @meiqimichelle) Can we set up a chat to discuss? I can work on this next week. thx!

[meiqimichelle]

We're going to split these into two issues. The map display should be separate for @ericronne to work on. The stats issue should remain for @shawnbot and @gemfarmer .

[shawnbot]

Okay, land ownership stats work will continue here. For map design concerns, see #1391.

[shawnbot]

For posterity: The current land ownership stats only list federally owned acreage and percentages by state:

AL:
  total_acres: 32678400
  federal_acres: 844026
  federal_percent: 2.6

There's also a US key in there, so you can get the nationwide federally owned acreage and percentage with:

{{ site.data.land_stats.US.federal_acres }}
{{ site.data.land_stats.US.federal_percent }}