Difference between revisions of "GSM"

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== GSM Product Family Description ==
+
== GSM Products Family Description ==
 +
<p>The ocean color products available here were made using Level 3, daily, binned imagery from SeaWiFS, MODIS-Aqua, Meris, and Viirs. The products themselves are 9km if SeaWiFS is involved, 4km otherwise, daily, 8-day and monthly imagery of GSM products, confidence intervals and coverage maps. The products were generated using the Garver-Siegel-Maritorena (GSM) model described in:<br>
 +
<br>
  
−
<p>The ocean color products available here were made using Level 3, daily, binned imagery from SeaWiFS, Meris, and MODIS-Aqua. The products themselves are 9km daily, weekly (8D) and monthly imagery of GSM products, confidence intervals and coverage maps. The products were generated using the Garver-Siegel-Maritorena (GSM) model described in:<br>
+
Maritorena S., D.A. Siegel & A. Peterson. 2002. Optimization of a Semi-Analytical Ocean Color Model for Global Scale Applications. Applied Optics. 41(15): 2705-2714.
−
<br>
 
−
Maritorena S., D.A. Siegel & A. Peterson. 2002. Optimization of a Semi-Analytical Ocean Color Model for Global Scale Applications. Applied Optics. 41(15): 2705-2714.[http://people.eri.ucsb.edu/~stephane/Maritorena_et_al_2002_AO4.pdf pdf]<br>
 
 
<br>
 
<br>
−
When multiple sensors are used, the GSM model uses the Normalized Water-Leaving radiances (LwNs) from all available sources over a given bin of the L3 grid as described in:<br>
+
When multiple sensors are used, the GSM model uses the remote-sensing reflectance (Rrs) from all available sources over a given bin of the L3 grid as described in:<br>  
 
<br>
 
<br>
−
Maritorena, S. and D.A. Siegel. 2005. Consistent Merging of Satellite Ocean Color Data Sets Using a Bio-Optical Model. Remote Sensing of Environment, 94(4): 429-440.[http://people.eri.ucsb.edu/~stephane/Marito_Siegel_merging_RSE.pdf pdf]<br>
+
Maritorena, S. and D.A. Siegel. 2005. Consistent Merging of Satellite Ocean Color Data Sets Using a Bio-Optical Model. Remote Sensing of Environment, 94(4): 429-440.
 
<br>
 
<br>
−
Maritorena S., O. Hembise Fanton d’Andon, A. Mangin, D.A. Siegel. 2010. Merged Satellite Ocean Color Data Products Using a Bio-Optical Model: Characteristics, Benefits and Issues. Remote Sensing of Environment, 114, 8: 1791-1804 (doi: 10.1016/j.rse.2010.04.002). [http://people.eri.ucsb.edu/~stephane/Maritorena_et_al_RSE_2010.pdf pdf]<br>
+
Maritorena S., O. Hembise Fanton d?Andon, A. Mangin, D.A. Siegel. 2010. Merged Satellite Ocean Color Data Products Using a Bio-Optical Model: Characteristics, Benefits and Issues. Remote Sensing of Environment, 114, 8: 1791-1804 (doi: 10.1016/j.rse.2010.04.002). [http://people.eri.ucsb.edu/~stephane/Maritorena_et_al_RSE_2010.pdf pdf]<br>
 
<br></p>
 
<br></p>
  
Line 17: Line 17:
 
For daily files:<br>
 
For daily files:<br>
 
<br>
 
<br>
−
Prod_name.YearDay.L3b_DAY.Sat_combo.Proc_vers.Type<br>
+
Prod_name.YearDay.L3[b|m]_DAY.Sat_combo.Proc_vers.Type<br>
 
<br>
 
<br>
−
where:<br>
 
 
<blockquote>
 
<blockquote>
−
Prod_name:<br>
+
        Prod_name:<br>
 
----------<br>
 
----------<br>
 
<table>
 
<table>
−
<tr><td>''GSMchl''</td> <td>(Chlorophyll concentration)</td></tr>
+
<tr><td>''GSMchl''</td><td>(Chlorophyll concentration)</td></tr>
 
<tr><td>''GSMacdm''</td><td>(Dissolved and detrital organic matter absorption coefficent at 443 nm)</td></tr>
 
<tr><td>''GSMacdm''</td><td>(Dissolved and detrital organic matter absorption coefficent at 443 nm)</td></tr>
 
<tr><td>''GSMbbp''</td><td>(Particulate backscattering coefficient at 443 nm)</td></tr>
 
<tr><td>''GSMbbp''</td><td>(Particulate backscattering coefficient at 443 nm)</td></tr>
Line 31: Line 30:
 
<tr><td>''GSMbbp_sig''</td><td>(Confidence interval of the bbp product)</td></tr>
 
<tr><td>''GSMbbp_sig''</td><td>(Confidence interval of the bbp product)</td></tr>
 
<tr><td>''GSMcovMask''</td><td>(Coverage map)</td></tr>
 
<tr><td>''GSMcovMask''</td><td>(Coverage map)</td></tr>
−
<tr><td>''GSMbin''</td><td>all the above in [http://oceancolor.gsfc.nasa.gov/DOCS/ocformats.html bin-indexed] format</td></tr>
+
<tr><td>''GSMbin''</td><td>(all the above in ISIN Grid bin format, instead of plate carrée mapped images)</td></tr>
−
</table>
+
</table>     
−
<br>
+
mapped products are 2160x4320 for combinations that include SeaWiFS, all others  4320x8640(4km)<br>
 +
 +
        bin format is  ISIN grid index and the products for the bin.  http://oceancolor.gsfc.nasa.gov/cms/L3Bins.html   1/12deg bin boundaries (9km) for SeaWiFS and 1/24 deg (4km) for all others.<br>
 +
 
 +
<br>
 
Year:<br>
 
Year:<br>
−
----------<br>
+
-------<br>
 
Year in yyyy format<br>
 
Year in yyyy format<br>
 
<br>
 
<br>
−
Day:<br>
+
Day<br>
−
----------<br>
+
-------<br>
 
Day in ddd format (i.e. sequential day of the year)<br>
 
Day in ddd format (i.e. sequential day of the year)<br>
 
<br>
 
<br>
−
Sat_combo:<br>
+
   
−
----------<br>
+
Sat_combo<br>
−
Describes which sensor or combination of sensors were used to produce the data: (formed from decimal representation of 4 bit flag,  lsb corresponds to Seawifs, 2nd is Aqua, 3rd Terra, 4th Meris)<br>
+
---------<br>
−
SeaWiFS only = 01<br>
+
Describes which sensor or combination of sensors were used to produce the data:<br>
−
MODIS-Aqua only = 02<br>
+
01 SeaWiFS only<br>
−
Meris only = 08<br>
+
02 or 'A' Aqua only ('A' is used 2012 and on)<br>  
−
SeaWiFS and Aqua = 03<br>
+
04 Meris only (else 'M')<br>
−
Meris and Aqua = 10<br>
+
                V Viirs only<br>
−
SeaWiFS,Meris, and Aqua = 11<br>
+
07 SeaWiFS, Aqua, and Meris<br>
−
<br>
+
                AV Aqua and Viirs<br>
−
Proc_vers:<br>
+
                AM Aqua and Meris<br>
−
----------<br>
+
<br>
−
Refers to the version of the data.<br>
 
  
−
'''Note on Version Number'''
+
−
Version 7 refers to Aqua [http://oceancolor.gsfc.nasa.gov/WIKI/OCReproc20120MA.html R2012.0], SeaWiFS [http://oceancolor.gsfc.nasa.gov/forum/oceancolor/topic_show.pl?pid=15555;hl=R2010#pid15555, R2010.0], Meris V3.1 Products that don't use Aqua, remain version 6.
+
Proc_vers<br>
−
 
+
---------<br>
−
Version 6 refers to SeaWiFS [http://oceancolor.gsfc.nasa.gov/forum/oceancolor/topic_show.pl?pid=15555;hl=R2010#pid15555, R2010.0], Meris  V3.1
+
Refers to the version of the data (current processing is 8 associated with the Aqua R2014.0 reprocessing effort http://oceancolor.gsfc.nasa.gov/WIKI/OCReproc20140MA.html with Meris R2012.1 http://oceancolor.gsfc.nasa.gov/cms/reprocessing/OCReproc20121ME.html) Version 6 is associated with the R2010 reprocessing effort (http://oceancolor.gsfc.nasa.gov/WIKI/OCReproc20100MA.html.  The latest processing versions can be found here http://oceancolor.gsfc.nasa.gov/cms/reprocessing.<br>
−
<br>
+
<br>
−
Type:<br>
+
Type<br>
−
----------<br>
+
-------<br>
−
Describes the type of file (HDF or PNG)<br>
+
Descibes the type of file (HDF or PNG)<br>
 
<br>
 
<br>
−
</blockquote>
 
 
 
−
'''Examples of daily file names''':
+
Examples of a daily file name:<br>
−
----------------<br>
+
------------------------------<br>
−
''GSMchl.2003121.L3b_DAY.01.6.hdf'' -> GSM chlorophyll product from SeaWiFS only L3b data for day 121 of 2003 (May 1, 2003), version 6<br>
+
GSMbbp.2008009.L3m_DAY.02.8.hdf  Aqua bbp<br>
−
<br>
+
GSMchl.2008009.L3m_DAY.07.8.hdf Seawifs Aqua Meris merged chl<br>  
−
''GSMacdm.2005021.L3b_DAY.03.5.hdf'' -> GSM acdm(443) product from SeaWiFS and MODIS-Aqua L3b data for day 21 of 2005 (January 21, 2005), version 5<br>
+
GSMcovMask.2008009.L3m_DAY.07.8.hdf  Seawifs Aqua Meris coverage <br>
−
<br>
+
GSMchl_sig.2012005.L3m_DAY.AV.8.png  Aqua Viirs merged chl confidence interval<br>
 +
GSMchl.2014013.L3m_DAY.V.8.hdf Viirs chl<br>
 +
GSMchl.2012013.L3m_DAY.06.8.hdf  Aqua Meris merged chl<br>
 +
GSMbin.2012013.L3b_DAY.04.8.hdf  Meris bin file<br>
 
<br>
 
<br>
−
For composite data:<br>
 
−
<br>
 
−
Prod_name.SYearSDayEYearEDay_ID.Sat_combo.Proc_vers.Type<br>
 
−
<br>
 
−
<blockquote>
 
−
Prod_name:<br>
 
−
----------<br>
 
−
same as for daily except no GSMcovMask.  In the GSMbin product the covMask SDS is
 
−
  replaced with the number of pixels composited.
 
  
−
Definitions of Sat_combo, Proc_vers and Type are identical to those for the daily files.<br>
+
For 8 day and monthly data<br>
 +
---------------------------<br>
 +
Prod_name.SYearSDayEYearEDay_ID.L3[b|m].Sat_combo.Proc_vers.Type<br>
 +
<br>
 +
Definitions of Prod_name, Sat_combo, Proc_vers and Type are identical to those for the daily files<br>
 
<br>
 
<br>
−
YearFDayYearLDay:<br>
+
YearFDayYearLDay<br>
−
----------<br>
+
-----------<br>
−
Year (in yyyy format)<br>  
+
Year (in yyyy format) <br>
 
First day (in ddd format, i.e. sequential day of the year) of daily data used to create the composite image.<br>
 
First day (in ddd format, i.e. sequential day of the year) of daily data used to create the composite image.<br>
−
Year (in yyyy format)<br>  
+
Year (in yyyy format) <br>
 
Last day (in ddd format) of daily data used to create the composite image.<br>
 
Last day (in ddd format) of daily data used to create the composite image.<br>
−
<br>
+
<br>
−
_ID:<br>
+
_ID<br>
−
----------<br>
+
-----<br>
−
 
+
is "_8D" for 8 Day and "_MO" for Monthly data. <br>
−
is "_4D" for four-day, "_8D" for weekly, and "_MO" for Monthly data<br>
+
<br>
−
<br>
+
Examples of composite images names<br>
−
</blockquote>
+
----------------------------------<br>
 +
GSMbbp.20080012008031.L3m_MO.07.8.png  Jan-2008 bbp from Seawifs Aqua Meris<br>
 +
GSMbbp.20083362008366.L3m_MO.04.8.hdf  Dec 2008 bbp from Meris<br>
 +
GSMbin.20080012008008.L3b_8D.02.8.hdf  8 day composite (days  1-8) from Aqua<br>
 +
GSMchl.20031852003192.L3b_8D.01.6.hdf  8 day composite (days185-192) SeaWiFS chl<br>
 +
<br>
  
−
'''Examples of composite image names''':<br>
 
−
----------------<br>
 
  
−
''GSMchl.20030012003031_MO.03.5.hdf'' -> Monthly GSM chlorophyll product from SeaWiFS and Aqua data for January 2003, version 5<br>
+
The data products are available in HDF (Hierarchical Data Format) files. Each product is represented in a 4320 x 2160 array. For each time period considered (Day, 8D, Monthly) there is one HDF file per product. HDF files are compressed and will self extract when opening. PNG images are also available for browsing purposes.  <br>
−
<br>
 
−
''GSMbbp.20050812005088_8D.02.5.hdf'' -> Weekly GSM bbp(443) product from Aqua only data (March 22-29, 2005), version 5<br>
 
−
<br>
 
−
<p>The data products are available in HDF (Hierarchical Data Format) files. Each product is represented in a 4320 x 2160 array. For each time period considered (Day, 8D, Monthly) there is one HDF file per product. HDF files are compressed and will self extract when opening. PNG images are also available for browsing purposes.  </p>
 
 
<br>
 
<br>
 
'''Product Units''':<br>
 
'''Product Units''':<br>
 
----------------<br>
 
----------------<br>
 
<table>
 
<table>
−
<tr><td>GSMchl</td><td>mg m<sup>-3</sup></td></tr>
+
<tr><td>Chlorophyll-a</td><td>mg m<sup>-3</sup></td></tr>
−
<tr><td>GSMacdm</td><td>m<sup>-1</sup></td></tr>
+
<tr><td>acdm443</td><td>m<sup>-1</sup></td></tr>
−
<tr><td>GSMbbp</td><td>m<sup>-1</sup></td></tr>
+
<tr><td>bbp443</td><td>m<sup>-1</sup></td></tr>
 
<tr></tr>
 
<tr></tr>
−
<tr><td>GSMchl_sig</td><td>mg m<sup>-3</sup></td></tr>
+
<tr><td>ci_Chloriphyll-a_sig</td><td>mg m<sup>-3</sup></td></tr>
−
<tr><td>GSMacdm_sig</td><td>m<sup>-1</sup></td></tr>
+
<tr><td>ci_acdm443</td><td>m<sup>-1</sup></td></tr>
−
<tr><td>GSMbbp_sig</td><td>m<sup>-1</sup></td></tr>
+
<tr><td>ci_bbp443</td><td>m<sup>-1</sup></td></tr>
 
</table>
 
</table>
 
<br>
 
<br>
Line 124: Line 122:
 
== Data (links to FTP site) ==
 
== Data (links to FTP site) ==
  
−
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Seawifs/ SeaWiFS]
+
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Seawifs/ SeaWiFS (9km)]
  
 
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Aqua/ MODIS Aqua (4km)]
 
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Aqua/ MODIS Aqua (4km)]
Line 130: Line 128:
 
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Meris/ Meris (4km)]
 
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/Meris/ Meris (4km)]
  
−
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedSAM/ Merged (Aqua,SeaWiFS,Meris 9km)]
+
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedSAM/ MergedSAM (Aqua,SeaWiFS,Meris 9km)]
  
−
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedAM4/ Merged (Aqua,Meris 4km starts 1/1/2011 ends 4/6/2012)]
+
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedAM4/ MergedAM (Aqua,Meris 4km starts 1/1/2011 ends 4/6/2012)]
  
−
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedAV4/ Merged (Aqua,Viirs 4km starts 1/2/2012]
+
* [ftp://ftp.oceancolor.ucsb.edu//pub/org/oceancolor/MEaSUREs/MergedAV4/ MergedAV (Aqua,Viirs 4km starts 1/2/2012]
  
 
== Acknowledgments & Citation ==
 
== Acknowledgments & Citation ==

Latest revision as of 08:32, 20 October 2015

GSM Products Family Description

The ocean color products available here were made using Level 3, daily, binned imagery from SeaWiFS, MODIS-Aqua, Meris, and Viirs. The products themselves are 9km if SeaWiFS is involved, 4km otherwise, daily, 8-day and monthly imagery of GSM products, confidence intervals and coverage maps. The products were generated using the Garver-Siegel-Maritorena (GSM) model described in:

Maritorena S., D.A. Siegel & A. Peterson. 2002. Optimization of a Semi-Analytical Ocean Color Model for Global Scale Applications. Applied Optics. 41(15): 2705-2714.
When multiple sensors are used, the GSM model uses the remote-sensing reflectance (Rrs) from all available sources over a given bin of the L3 grid as described in:

Maritorena, S. and D.A. Siegel. 2005. Consistent Merging of Satellite Ocean Color Data Sets Using a Bio-Optical Model. Remote Sensing of Environment, 94(4): 429-440.
Maritorena S., O. Hembise Fanton d?Andon, A. Mangin, D.A. Siegel. 2010. Merged Satellite Ocean Color Data Products Using a Bio-Optical Model: Characteristics, Benefits and Issues. Remote Sensing of Environment, 114, 8: 1791-1804 (doi: 10.1016/j.rse.2010.04.002). pdf

File Naming convention:


For daily files:

Prod_name.YearDay.L3[b|m]_DAY.Sat_combo.Proc_vers.Type

Prod_name:
----------

GSMchl(Chlorophyll concentration)
GSMacdm(Dissolved and detrital organic matter absorption coefficent at 443 nm)
GSMbbp(Particulate backscattering coefficient at 443 nm)
GSMChl_sig(Confidence interval of the Chl product)
GSMacdm_sig(Confidence interval of the acdm product)
GSMbbp_sig(Confidence interval of the bbp product)
GSMcovMask(Coverage map)
GSMbin(all the above in ISIN Grid bin format, instead of plate carrée mapped images)

mapped products are 2160x4320 for combinations that include SeaWiFS, all others 4320x8640(4km)

bin format is ISIN grid index and the products for the bin. http://oceancolor.gsfc.nasa.gov/cms/L3Bins.html 1/12deg bin boundaries (9km) for SeaWiFS and 1/24 deg (4km) for all others.


Year:
-------
Year in yyyy format

Day
-------
Day in ddd format (i.e. sequential day of the year)

Sat_combo
---------
Describes which sensor or combination of sensors were used to produce the data:
01 SeaWiFS only
02 or 'A' Aqua only ('A' is used 2012 and on)
04 Meris only (else 'M')
V Viirs only
07 SeaWiFS, Aqua, and Meris
AV Aqua and Viirs
AM Aqua and Meris


Proc_vers
---------
Refers to the version of the data (current processing is 8 associated with the Aqua R2014.0 reprocessing effort http://oceancolor.gsfc.nasa.gov/WIKI/OCReproc20140MA.html with Meris R2012.1 http://oceancolor.gsfc.nasa.gov/cms/reprocessing/OCReproc20121ME.html) Version 6 is associated with the R2010 reprocessing effort (http://oceancolor.gsfc.nasa.gov/WIKI/OCReproc20100MA.html. The latest processing versions can be found here http://oceancolor.gsfc.nasa.gov/cms/reprocessing.

Type
-------
Descibes the type of file (HDF or PNG)

Examples of a daily file name:


GSMbbp.2008009.L3m_DAY.02.8.hdf Aqua bbp
GSMchl.2008009.L3m_DAY.07.8.hdf Seawifs Aqua Meris merged chl
GSMcovMask.2008009.L3m_DAY.07.8.hdf Seawifs Aqua Meris coverage
GSMchl_sig.2012005.L3m_DAY.AV.8.png Aqua Viirs merged chl confidence interval
GSMchl.2014013.L3m_DAY.V.8.hdf Viirs chl
GSMchl.2012013.L3m_DAY.06.8.hdf Aqua Meris merged chl
GSMbin.2012013.L3b_DAY.04.8.hdf Meris bin file

For 8 day and monthly data


Prod_name.SYearSDayEYearEDay_ID.L3[b|m].Sat_combo.Proc_vers.Type

Definitions of Prod_name, Sat_combo, Proc_vers and Type are identical to those for the daily files

YearFDayYearLDay
-----------
Year (in yyyy format)
First day (in ddd format, i.e. sequential day of the year) of daily data used to create the composite image.
Year (in yyyy format)
Last day (in ddd format) of daily data used to create the composite image.

_ID
-----
is "_8D" for 8 Day and "_MO" for Monthly data.

Examples of composite images names


GSMbbp.20080012008031.L3m_MO.07.8.png Jan-2008 bbp from Seawifs Aqua Meris
GSMbbp.20083362008366.L3m_MO.04.8.hdf Dec 2008 bbp from Meris
GSMbin.20080012008008.L3b_8D.02.8.hdf 8 day composite (days 1-8) from Aqua
GSMchl.20031852003192.L3b_8D.01.6.hdf 8 day composite (days185-192) SeaWiFS chl


The data products are available in HDF (Hierarchical Data Format) files. Each product is represented in a 4320 x 2160 array. For each time period considered (Day, 8D, Monthly) there is one HDF file per product. HDF files are compressed and will self extract when opening. PNG images are also available for browsing purposes.

Product Units:


Chlorophyll-amg m-3
acdm443m-1
bbp443m-1
ci_Chloriphyll-a_sigmg m-3
ci_acdm443m-1
ci_bbp443m-1


Data (links to FTP site)

Acknowledgments & Citation

If you use the GSM products for a work that appears in a publication, please give proper credit to our work by citing the 2010 RSE paper:

Maritorena S., Hembise Fanton d’Andon O., Mangin A., Siegel D.A. 2010. Merged Satellite Ocean Color Data Products Using a Bio-Optical Model: Characteristics, Benefits and Issues. Remote Sensing of Environment, 114, 8: 1791-1804 (doi: 10.1016/j.rse.2010.04.002).pdf

and/or by mentioning the source of the data in the "Methods" section or the acknowledgements with something like:

The satellite CHL (and/or CDM and/or BBP) data were obtained from the Ocean Color MEaSUREs project at UCSB (http://wiki.icess.ucsb.edu/measures/Products).

Metadata

  • GSM01 Validation Results

Matchups using daily level-3 data (see Maritorena et al., 2010).

  • (recent results TBA)

Software


References

Maritorena S., O. Hembise Fanton d’Andon, A. Mangin, D.A. Siegel. 2010. Merged Satellite Ocean Color Data Products Using a Bio-Optical Model: Characteristics, Benefits and Issues. Remote Sensing of Environment, 114, 8: 1791-1804 (doi: 10.1016/j.rse.2010.04.002). pdf

Maritorena, S., and D.A. Siegel, 2005: Consistent merging of satellite ocean color data using a semi-analytical model, Remote Sensing of the Environment, 94, 429-440. pdf

Siegel, D.A., Maritorena, S., Nelson, N.B., Hansell, D.A., Lorenzi-Kayser, M., 2002. Global distribution and dynamics of colored dissolved and detrital organic materials. Journal of Geophysical Research, 107, 3228, doi:10.1029/2001JC000965. pdf

Maritorena, S., D.A. Siegel and A.R. Peterson, 2002: Optimization of a semianalytical ocean color model for global-scale applications. Applied Optics-LP, 41, 2705-2714. pdf

Garver, S.A., and D.A. Siegel, 1997: Inherent optical property inversion of ocean color spectra and its biogeochemical interpretation: I. Time series from the Sargasso Sea. Journal of Geophysical Research., 102, 18,607-18,625. pdf

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