29

It is on the new version of American Factfinder and don't feel bad, even Census Bureau employees are confounded by the new site. Example for population and housing for Newark, DE: Go to http://factfinder2.census.gov Choose 'Advanced Search' > 'Show Me All' Start searching for the theme you're after: Under Topics choose People > Basic Count/Estimate > ...


21

There are 13 multi-state US Census' ZIP Code Tabulation Areas (ZCTAs): 02861, 42223, 59221, 63673, 71749, 73949, 81137, 84536, 86044, 86515, 88063, 89439 & 97635. As others have mentioned, there are a few different ways to figure out the area covered by a ZIP Code, but ZCTAs are the easiest, and the only official version that I know of. So your ...


19

I don't know which projection engine ArcGis uses, but a very interesting question also for proj.4. So I give it a try to test the proj.4 projection engine within the GNU-R environment. I use the NAD 83 - UTM 17 corners and EPSG 26917 and reproject it 10000 and 1000000 times recursivly and calculate the difference to the start values. Here are the results: ...


19

There are no duplicate ZIP Codes. There are some ZIP Codes that are multi-part polygons, but those polygons are usually adjacent. Source: I manage/update ZIP Codes for the USPS


17

The Albers equal area conic is the typical projection for historical USGS maps of the lower 48, it being a general-purpose low-distortion compromise for mid-latitude short and wide extents. As a reference on map projections, I like the ESRI book Understanding Map Projections. Its first 30 pages are not unlike a short textbook, followed by ~70 pages of ...


15

Attempt to answer my own question: The cause of striping in the examples I provided are entirely due to my workflow, not any legacy issue with how the data was originally assembled or mosaiced together. The DEMs I was dealing with were all generated from newer techniques, as evidenced by this map: The two methods that cover the areas I was working with ...


13

There are some free applications that let you try and play with projections. like: flexprojector They also indicate to what extend they preserve size, shape or direction. Depending on you application a different priority might be set. For instance if I had to map an areal phenomenon like e.g. certain species habitat zones I'd prefer a projection that ...


12

In my experience, it usually means what you think it means: a range of address numbers. I've also seen it used as a way of writing an apartment or suite number, so 136-39 37 AVE would be 136 37th Ave, Apt. 39, and 1221-102 CANYON ROCK CT would be 1221 Canyon Rock Ct, Apt. 102. It's not a very good way to denote an apartment/room/suite number but I've seen it ...


11

This was down a bit in the comments at the link you provided: SF uses State Plane, NAD 83, Zone 3, US Survey Feet. This coordinate system is used vs lat/longs as they have greater accuracy for smaller areas. We are looking at ways to convert this to lat/long to make it easier for consumers to use.


11

There really isn't a way to tell this; since there is not a ZipCode boundary shape that is defined by the USPS. ZipCodes are defined by a bounding box of Streets delivered to by carriers from a particular distribution center. So you would need to take the USPS AIS data and extract by ZipCodes the streets that are delivered by a given Post Office, then Join ...


10

Microsoft just open sourced 124,885,597 million computer generated building footprints in all 50 US states https://github.com/Microsoft/USBuildingFootprints


10

If using the Google Geocoding API or another online source is your preference rather than local options, I'd suggest looking into the Tor Project (easily installed through the bundle called 'the Vidalia Bundle'). Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents .....


10

I found something closer to what I was looking for (US State and County boundaries) on github: https://github.com/johan/world.geo.json/tree/master/countries/USA The features are very generalized/simplified, but they'll work for a national scale map. Country boundaries for the whole world are available in this repo too.


9

You can download NED data for entire counties and also entire states (though I've never needed an entire state) using the National Map Viewer, click the "Download Data" button in the upper-right, then choose Counties or States as your reference area, click the county/state you're interested in, and a list of (usually just one) search result pops up on the ...


9

GEOID is the field used to join TIGER/Line geographic data to the demographic data in various American Community Survey products and in the Decennial Census. It is slightly confused by the fact that this field is called GEOID10 only in the TIGER/Line 2010 products (in fact, almost all of the field names in TIGER/Line 2010 end in 10), and by the fact that the ...


9

ESRI has defined three projections especially for the contiguos United states. These are included in QGIS as well: EPSG:102003 USA_Contiguous_Albers_Equal_Area_Conic +proj=aea +lat_1=29.5 +lat_2=45.5 +lat_0=37.5 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD83 +units=m +no_defs EPSG:102004 USA_Contiguous_Lambert_Conformal_Conic +proj=lcc +lat_1=33 +lat_2=45 +lat_0=39 ...


9

My guess is that 0558253.7 13083091W translates to 055.82537°N 130.83091°W which are decimal degrees lat and long, or 55° 49' 31.3" N and 130° 49' 51.3" W in deg-min-sec, located somewhere in the Alaska panhandle.


8

http://www.census.gov/geo/www/tiger/tgrshp2010/tgrshp2010.html allows you to download census blocks by county. Update: the TIGER/shapefiles does not have any demographic data - if that's what you are looking for you would need American FactFinder.


8

They are available on the Census FTP site at http://www2.census.gov/geo/tiger/TIGER2010BLKPOPHU/


8

The TIGER data from the census bureau is available at http://www.census.gov/geo/www/tiger/


8

Get a zip-code boundary layer and run Polygon Neighbors. Review How Polygon Neighbors Works and Up-To-Date Zip-Code Boundaries Picture below might be different than your ArcMap looks, but the buttons and procedure should be the same. Perhaps this is an open-source solution. I have not tested or used this solution which seems to require GRASS 6+ : from the ...


8

I just checked my old National Atlas bookmark and was redirected not to the National Map Viewer, but to the National Map's Small Scale data page. There are 197 datasets available for download there, to my eyes it looks like it's the same data that was available at the old National Atlas page and they just moved it to the new URL. Are you not being forwarded ...


8

I worked on updating some USGS quads, back in the 90s. It seemed like most of the style guidelines were published internally, long before the Internet, and never made it online. It's fairly common to show two sets of State Plane Coordinate System grid tics on quadrangles that are near a boundary between two zones. With UTM zones, it isn't such a big ...


8

It looks like it could be from the Project Linework website. Specifically, the "Angular" or "Twenty Seventy" datasets.


7

I poked around on the State of Hawaii GIS site but most of the layers were too general or too old. The NOAA Coastal Services Center has some Landsat ETM derived land-cover data for Hawaii. There's also some 2.4m Quickbird-derived land-cover data for all islands except the Big Island. Hope that helps!


7

Another USGS site is seamless.usgs.gov, been using that for years now. In the Download tab, select the NED version you want, then draw your area to download using the tool from the Downloads toolbar on the left. There are other methods of extracting areas as well in that toolbar. You can get GeoTiff or binary grids. Another option is bulk download, where ...


7

This data layer type is not usually freely distributed because: Privately owned (utility company) May not be in digital format If you want to see a general data model, check out the ArcGIS Pipeline Data Model.


7

I am not aware of any free source of shapefiles for pipelines. PHMSA's National Pipeline Mapping System (NPMS) does provide a viewer but it doesn't allow data to be downloaded. NPMS data can only be viewed one county at a time which is rather hard to use. NPMS data consists of gas transmission pipelines and hazardous liquid trunklines. It does not contain ...


7

The US Census Bureau derives approximate boundaries for ZIP codes based on the addresses contained within them, called ZIP Code Tabulation Areas (ZCTAs). They publish relationship files that describe how their ZCTAs map to various other geographies. If you examine the ZCTA to Place relationship file you can see how they map to cities and towns. You can ...


7

One could use either kind of latitude to locate points on the WGS 84 ellipsoid (used by the NED) or any other ellipsoid, but "everybody knows" that the values will always be given as geodetic latitudes. However, it is surprisingly hard to find an authoritative statement to that effect! Before we go on, it helps to understand that although a datum like the ...


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