Using IDL with Suomi NPP VIIRS Data

Using IDL with NPP VIIRS Data

HDF & HDF-EOS Workshop XV

Mark Piper

[email protected] idldatapoint.com

The information contained in this document pertains to software products and services that are subject to the controls of the Export Administration Regulations (EAR). The recipient is responsible for ensuring compliance to all applicable U.S. Export Control laws and regulations.

Agenda

> Overview of VIIRS data

> Using IDL with VIIRS data (examples)

> Summary / Q&A

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Presentation files: exelisvis.com/esg/Seminars.aspx

HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

About Suomi NPP VIIRS

> Overview: http://npp.gsfc.nasa.gov/viirs.html

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VIIRS data overview

> Data from NOAA CLASS site (http://www.class.ngdc.noaa.gov)

> VIIRS I-Band (imaging channel) EDR (level 2); single HDF5 file

> I(1,2,3,4,5) and GEO info (Longitude, Latitude, Height, etc.)

> Four granules:

> Band comparison:

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375 m pixel size granule

8241 pixels (~3100 km)

1541 pixels (~578 km)

cross

alo

ng

HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Example #0

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namespace = 'vis_viirs_'

display_domain

viirs_file string

.kml file

> Browse a VIIRS I-Band file with TX_NPP_BROWSER.

> View the domain of the data with IDL or Google Earth / NASA World Wind.

HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Example #1

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namespace = 'vis_viirs_'

make_rgb

viirs_file string

rgb bytarr [8241,6164,3]

scale_dataset

read_dataset

> Construct a VIIRS I-Band (3,2,1) false color composite image.

HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Example #1

7 HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Example #2

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namespace = 'vis_viirs_'

make_cloudmask

viirs_file string

mask bytarr [8241,6164]

scale_dataset

read_dataset

> Construct a cloud mask from VIIRS I-Band imagery.

HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Example #2

9 HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

References

Here are a few references that I found helpful in making this presentation.

> Suomi NPP Science Documents:

http://npp.gsfc.nasa.gov/science/documents.html

> About VIIRS:

http://npp.gsfc.nasa.gov/viirs.html

http://www.nesdis.noaa.gov/jpss/instruments.html

> Landsat 7 Automatic Cloud Cover Assessment:

http://landsathandbook.gsfc.nasa.gov/pdfs/ACCA_SPIE_paper.pdf

10 HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Summary

HDF5 makes it easy to work with Suomi NPP VIIRS data in IDL!

11 HDF and HDF-EOS Workshop XV 2012-April-19 Riverdale, MD

Using IDL with NPP VIIRS Data

HDF & HDF-EOS Workshop XV

Mark Piper

[email protected] idldatapoint.com

The information contained in this document pertains to software products and services that are subject to the controls of the Export Administration Regulations (EAR). The recipient is responsible for ensuring compliance to all applicable U.S. Export Control laws and regulations.

Presentation files: exelisvis.com/esg/Seminars.aspx