National Agriculture Imagery Program
Encyclopedia
The National Agriculture Imagery Program (NAIP) acquires aerial imagery during the agricultural growing seasons in the continental United States. It is administered by the USDA's Farm Service Agency
(FSA) through the Aerial Photography Field Office (APFO) in Salt Lake City.
A primary goal of the NAIP program is to make digital ortho photography
available to governmental agencies and the public within a year of acquisition. This "leaf-on" imagery is used as a base layer for GIS programs in FSA's County Service Centers, and is used to maintain the Common Land Unit
(CLU) boundaries. Projects are contracted each year based upon available funding and the FSA imagery acquisition cycle. Beginning in 2003, NAIP was acquired on a 5-year cycle. 2008 was a transition year, and a three-year cycle began in 2009. Since the NAIP program began in 2003, vendors have been transitioning to digital sensors in imagery acquisition. In 2009, most NAIP imagery will be acquired with digital sensors rather than film cameras.
NAIP imagery products are available either as digital ortho quarter quad tiles (DOQQs) or as compressed county mosaics (CCM). The area for DOQQs corresponds to the USGS topographic quadrangles. Each image tile covers a 3.75 x 3.75 minute quarter quadrangle plus a 300 meter buffer on all four sides. CCMs are generated by compressing DOQQ image tiles into a single mosaic.
All individual tile images and the resulting mosaic are rectified in the UTM coordinate system, NAD 83, and cast into a single predetermined UTM zone.
NAIP imagery is acquired at a one-meter ground sample distance
(GSD) with a horizontal accuracy that matches within six meters of photo-identifiable ground control points. The default spectral resolution
is natural color (Red, Green and Blue, or RGB) but beginning in 2007, some states have been delivered with four bands of data: RGB and Near Infrared. Images have no more than 10% cloud cover
per quarter quad tile, weather conditions permitting.
Farm Service Agency
The Farm Service Agency is the USDA agency into which were merged several predecessor agencies, including the Agricultural Stabilization and Conservation Service . The ASCS was, as the FSA is now, primarily tasked with the implementation of farm conservation and regulation laws around the country...
(FSA) through the Aerial Photography Field Office (APFO) in Salt Lake City.
A primary goal of the NAIP program is to make digital ortho photography
Orthophoto
An orthophoto, orthophotograph or orthoimage is an aerial photograph geometrically corrected such that the scale is uniform: the photo has the same lack of distortion as a map...
available to governmental agencies and the public within a year of acquisition. This "leaf-on" imagery is used as a base layer for GIS programs in FSA's County Service Centers, and is used to maintain the Common Land Unit
Common Land Unit
A Common Land Unit is the smallest unit of land that has a permanent, contiguous boundary, a common land cover and land management, a common owner and a common producer in agricultural land associated with USDA farm programs. CLU boundaries are delineated from relatively permanent features such as...
(CLU) boundaries. Projects are contracted each year based upon available funding and the FSA imagery acquisition cycle. Beginning in 2003, NAIP was acquired on a 5-year cycle. 2008 was a transition year, and a three-year cycle began in 2009. Since the NAIP program began in 2003, vendors have been transitioning to digital sensors in imagery acquisition. In 2009, most NAIP imagery will be acquired with digital sensors rather than film cameras.
NAIP imagery products are available either as digital ortho quarter quad tiles (DOQQs) or as compressed county mosaics (CCM). The area for DOQQs corresponds to the USGS topographic quadrangles. Each image tile covers a 3.75 x 3.75 minute quarter quadrangle plus a 300 meter buffer on all four sides. CCMs are generated by compressing DOQQ image tiles into a single mosaic.
All individual tile images and the resulting mosaic are rectified in the UTM coordinate system, NAD 83, and cast into a single predetermined UTM zone.
NAIP imagery is acquired at a one-meter ground sample distance
Ground sample distance
In remote sensing, ground sample distance in a digital photo of the ground from air or space is the distance between pixel centers measured on the ground. For example, in an image with a one-meter GSD, adjacent pixels image locations that are 1 meter apart on the ground...
(GSD) with a horizontal accuracy that matches within six meters of photo-identifiable ground control points. The default spectral resolution
Spectral resolution
The spectral resolution of a spectrograph, or, more generally, of a frequency spectrum, is a measure of its ability to resolve features in the electromagnetic spectrum...
is natural color (Red, Green and Blue, or RGB) but beginning in 2007, some states have been delivered with four bands of data: RGB and Near Infrared. Images have no more than 10% cloud cover
Cloud cover
Cloud cover refers to the fraction of the sky obscured by clouds when observed from a particular location...
per quarter quad tile, weather conditions permitting.