In addition, the United State Geological Survey (USGS) National Map and the USGS EROS Data Center have aerial photography available for download. Most of this imagery is available for rural areas (sometimes urban areas are not available). The NAIP imagery can also be ordered online. These data can be streamed to your GIS application through an ArcIMS data service called the NAIP Data Viewer, or it can be downloaded (MrSid format) from the NRCS Geospatial Data Gateway. National Agricultural Imagery is a mosaic collection of 1-meter color, geo-referenced aerial photographs. The USDA, through the Aerial Photography Field Office (APFO), provides access to aerial photography acquired through the National Agricultural Imagery Program (NAIP). Try the national Geospatial One Stop to identify a wide variety of NGDC options which may have imagery of your area. The primary function of these organizations is to catalog and make aerial imagery discoverable. This information can be accessed through the National States Geographic Information Council (NSGIC) Web site.Īnother source of imagery is the National Geospatial Data Clearinghouses (NGDC). To determine the status of state-conducted imagery programs, contact your state GIS coordinator. Many regional and local governments have aerial imagery available free or at low cost. Highly accurate aerial imagery can be used as base data in a Geographic Information System (GIS) to help spatially correct or reference other data.Ĭheck your state, local, and regional governments for imagery in your state. If the aerial data contains metadata, you will be able to learn a great deal about the imagery, including its accuracy. Many of these states provide free imagery in 1 meter or 2 meter resolutions (pixel size) through a state imagery clearinghouse, and newer public domain aerial imagery may have an even finer resolution of 6 to 12 inches. Most states have participated in national and statewide imagery programs since the middle 1990s (some have been involved even longer). However, there are sources from which you may be able obtain aerial imagery for your area free of charge. Aerial photography is one type of geospatial data that may require a large monetary investment. Labels containing this ± symbol include data dependent on parcel lines.Aerial imagery can be very useful in the classroom, public meetings, and land management planning and for general historical purposes.The links below represent the most recent available data.Downloads are compressed zip files consisting of all necessary files for each data set including projection files and metadata.Metadata is provided in *.met text file, html, or xml files.In some cases, data must be acquired from the original source. Humboldt County is not the source for all data listed below. Most Humboldt County GIS data is in CA State Plane Zone 1 NAD27 Units Feet coordinates. GIS data is in CA State Plane Zone 1, UTM Zone 10, or Albers Equal Area projection coordinates. In rural areas the map data may be inaccurate by as much as 400 feet in any direction. In urban areas the GIS map data maybe inaccurate by as much as 50 feet in any direction. All GIS data should be verified before it is materially relied upon for property or project planning. While the GIS is useful for planning purposes, it should not be relied upon to determine property, zoning or general plan designation boundaries or be used in any way for project design. The accuracy of map data varies from location to location in the county. In the event of any difference or error, the law will take precedence. While every effort has been made to assure the accuracy of this information, it should be understood that it does not have the force and effect of law, rule, or regulation. The department assumes no liability or responsibility in the use of this data. It has not been fully reviewed for accuracy and is intended to be used for planning purposes only. The County of Humboldt makes no guarantee of the quality or completeness of this data. To access our web mapping applications, please visit our Web GIS.
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