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Earth2012 degree-2160 topography, shape and potential models - readme-file V1.0
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Contact: Christian Hirt 
Western Australian Centre for Geodesy
Curtin University Perth
c.hirt(use the at here)curtin.edu.au &
c.hirt(use the at here)tum.de

Last edited 2015-03-24

1. SUMMARY
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Earth2012 is the first release of Earth's topography models (topography, 
bedrock, rock-equivalent topography) in spherical harmonic coefficients to
harmonic degree 2160. The model suite provides spherical harmonic coefficients 
of   1.) elevation grids,  2.) Earth shape grids, and 3.) Earth topographic 
potential. The models were released back in August 2012. In March 2015, they
have been updated by the Earth2014 suite of models which is based on newer data 
sets and offers higher resolution. The Earth2012 models will be maintained as
archive.

The use of Earth2014 data sets is recommended.

Permanent link to the Earth2012/14 data sets 
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http://ddfe.curtin.edu.au/models/Earth2012/            
http://ddfe.curtin.edu.au/models/Earth2014/ 

2. INPUT DATA AND PROCESSING
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is described at geodesy.curtin.edu.au/research/models/Earth2012/
which is available as pdf-copy at
http://ddfe.curtin.edu.au/models/Earth2012/earth2012_website.pdf

3. DIFFERENCES EARTH2012 and EARTH2014
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The most important differences are:
- Earth2014 has been released as gridded data (1-arcmin and 5 arcmin) and as
  SHCs up to degree 10,800 [Earth2012 only in SHCs to degree 2,160]
- Earth2014 is based on up-to-date data sets, notably Bedmap2 over Antarctica
  [Earth2012 is based on older data such as ETOPO1/Bedmap1 over Antarctica].
  Updates  are also over Greenland and the Oceans.
- The Earth2014 models offer a significantly improved description of the 
  masses.

4. EARTH2012 ARCHIVED PRODUCTS
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are organized in following directories

/topo_shape_to2160      .. contains SHCs of the Earth2012 topography and
                           shape files, all represented in spherical harmonics
                           to degree 2160
                               
/potential_models       .. contains SHCs of the topographic potential models 
                           dV_SPH_RET2012 and of dV_ELL_RET2012, and a guide
                           on the use of these models

/icgem_delivery         .. as before, but with header information and in 
                           IAG's ICGEM format. Data in this folder has been
                           delivered to http://icgem.gfz-potsdam.de/ICGEM/

/pdf_journal_papers     .. pdf copies of journal papers describing the 
                           development and use of the Earth2012 models
  
REFERENCES
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are given in file
http://ddfe.curtin.edu.au/models/Earth2012/earth2012_website.pdf
and in the journal papers in folder
http://ddfe.curtin.edu.au/models/Earth2012/pdf_journal_papers

DISCLAIMER
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Neither Curtin University nor any of its staff accept any liability in 
connection with the use of data and models provided here. Neither Curtin 
University nor any of its staff make any warranty of fitness, completeness, 
usefulness and accuracy of the data and models for any intented or unintended 
purpose.