SRTM Grid Cell Area (3" resolution) derived from 3" SRTM DEM-S

Collection Title:

SRTM Grid Cell Area (3" resolution) derived from 3" SRTM DEM-S

Collection Description:

The SRTM grid cell area dataset has values of cell area in square metres. The grid cell area product was derived from the Smoothed Digital Elevation Model (DEM-S; ANZCW0703014016), which was derived from the 1 second resolution SRTM data acquired by NASA in February 2000. The calculation of grid cell area from the DEM-S accounted for the varying... more spacing between grid points in the geographic projection. less

Field of Research:

Environmental Management ;  Land Capability and Soil Degradation ;  Landscape Ecology ;  Natural Resource Management ;  Soil Sciences not elsewhere classified

DOI:

https://doi.org/10.4225/08/50AC89675E6DD

Start Date:

11 Feb 2000

End Date:

22 Feb 2000

Contact:CSIRO Enquiries
 CSIROEnquiries@csiro.au
 1300 363 400
Keywords:

Grid Cell Area ;  LAND Topography Models ;  ECOLOGY Landscape ;  TERN_Soils ;  Land Surface ;  Australia

Lineage:

Source data 1. 3 second SRTM-derived Smoothed Digital Elevation Model (DEM-S; ANZCW0703014016) Area calculation The 3 second resolution data has a cell size of 0.0008333333333 decimal degrees and the 1 degree extent input tiles have 1200 rows and 1200 columns. Cell width changes with latitude (decreases as latitude increases); width is recalculated for each row in the grid based on the centre of the cell. Radius for calculating distance around a parallel (constant latitude, in radians): N = a / sqrt ( 1 - e^2 sin^2(lat) ) e^2 is the square of the eccentricity, calculated from flattening (f) Radius for calculating distance along a meridian (constant longitude): M = a ( 1 - e^2 ) / ( 1 - e^2 sin^2(lat) ) ^ (3/2) The 1 - e^2 sin^2(lat) term is used in both M and N, so it is calculated as p a = 6 378 137 m (in WGS84) f = 1/298.257223563 (in WGS84) e2 = f * (2 - f) p = 1 - e2 * sqr(sin(lat)) N = a / sqrt(p) M = a * (1 - e2) / (p * sqrt(p)) The length of 1 degree in longitude and latitude are: long_len = N * cos(lat) * PI / 180.0 lat_len = M * PI / 180.0 The area of a 3 second grid cell is: lat_len * long_len / 1200^2

Credit:

Access to this data has been made possible by the Terrestrial Ecosystem Research Network (TERN), supported by the Australian Government through the National Collaborative Research Infrastructure Strategy and the Super Science Initiative.

Licence:

Creative Commons Attribution 3.0 Unported Licence

Organisations:

CSIRO (Australia)

Attribution Statement:

Gallant, John; Austin, Jenet (2012): SRTM Grid Cell Area (3" resolution) derived from 3" SRTM DEM-S. v1. CSIRO. Data Collection. https://doi.org/10.4225/08/50AC89675E6DD

Rights Statement:

All Rights Reserved (including copyright) CSIRO Australia 2012.

Access:

The metadata and files (if any) are available to the public.