What projection are the imagery services in The National Map viewer?

Imagery services in The National Map (TNM) use WGS 1984 Web Mercator (Auxiliary Sphere). The USGS ImageryOnly Service (under Base Maps) is cached (pre-generated) at this projection. Imagery services can be easily reprojected to many other popular projections for use in GIS desktop applications as background services.

Learn more: Training videos for using The National Map Products and Services

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What is the difference between tiled and dynamic services?

A tiled service contains cached tiles that render the map in small tile images. This allows the map to perform much faster when panning and zooming, compared to a dynamic service. Dynamic is considered an "older" way of displaying web maps, where each feature is called from the source data and drawn separately for every pan and zoom. Tiled base...

Are the scanned aerial photographic images georectified?

Scans of traditional aerial photography film products (air photos) are not georectified . The USGS does, however, offer several orthoimagery (georectified aerial photograph) products: Digital Orthophoto Quadrangle (DOQ) High Resolution Orthoimagery (HRO) National Agriculture Imagery Program (NAIP, NAIP Plus) NAIP orthoimagery has been collected...

How often is orthoimagery in The National Map updated and what are the acquisition dates?

Orthoimagery (georectified aerial photography) available through The National Map Downloader and The National Map Services is from the USDA Farm Service Agency's National Agricultural Imagery Program (NAIP), which is 1-meter resolution. Generally, NAIP imagery is refreshed on a 3-year cycle with approximately one third of the continental U.S...

What are the URLs for imagery services in The National Map, and are they cached or dynamic?

There are several imagery services for The National Map . Some imagery services are cached and some are dynamic: USGSImageryOnly (under Base Maps), for example, is a tile cache base map service of orthoimagery. It has different imagery data sources depending on view scale. The USGSImageryOnly service uses cache tiles of 256x256 pixels in size and...

What do the different colors in a color-infrared aerial photograph represent?

Color-infrared (CIR) aerial photography--often called "false color" photography because it renders the scene in colors not normally seen by the human eye--is widely used for interpretation of natural resources. Atmospheric haze does not interfere with the acquisition of the image. Live vegetation is almost always associated with red tones. Very...
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Date published: October 21, 2019

Aerial Photo Scan Reveals Rare Image of Two Airplanes in Flight

Every work day at the USGS Earth Resources Observation and Science (EROS) Center, contractor Mike Austad pulls up a chair and begins scanning aerial photographs of the Earth’s surface into the massive public database that is EarthExplorer.

Date published: August 27, 2018

Hazards Data Distribution System Releases Thousands of Aerial Images of Kilauea Impact

The eruptive behavior of the Kilauea volcano that began in May 2018 on Hawaii’s Big Island has created an unparalleled opportunity for understanding volcanic systems.

Date published: May 23, 2018

Keeping Current with Map Services Made Easier

The National Map provides a new Simple Notification Service and has new URLs for some of its thematic cartographic map services.

Date published: November 1, 2016

USGS National Map Orthoimagery Map Services Transition and Other Map Service Changes

As part of The National Map transition to cloud hosting, several of the National Map NAIP Orthoimagery Services will be provided under new URLs.

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Updated 2015 version of Saint Landry quadrangle with orthoimage turned on

Updated 2015 version of Saint Landry quadrangle with orthoimage turned on

Updated 2015 version of Saint Landry quadrangle with orthoimage turned on. (1:24,000 scale) 

Images from HDDS Explorer

Images from HDDS Explorer

Various images from HDDS Explorer including a cyclone, fire, flood, tornado, earthquake, and volcano