MERRA Data Access and Services

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MERRA Data Access and Services
Stephen Berrick GES DISC, NASA GSFC Dana
Ostrenga GES DISC, NASA GSFC Suhung Shen GES
DISC, GMU
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What is Giovanni?
Giovanni is a Web-based application developed by
the GES DISC that provides a simple and easy way
to visualize, analyze, and access vast amounts of
Earth science remote sensing and model data.
Only a Web browser is needed. There is no
need to learn data formats, programming, or
download large amounts of data.
Visualizations for MERRA data include
latitude-longitude maps, time series diagrams,
latitude-time and longitude-time Hovmöller
diagrams, and animations. New visualizations will
be introduced over time.
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Giovanni is Easy to Use
Users simply make selection criteria
Spatial Area
Parameters
Time Range
Visualization
Vertical Levels for 3D
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Giovanni - Results
Result Image/Animation
Spatial selection
Temporal Selection
Image Resize
Additional revision parameters Decoration
Axes etc Color bar Projection
Pixilation
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What is currently in Giovanni?
Currently available Giovanni instances
are Monthly 2D Monthly 3D
http//gdata1.sci.gsfc.nasa.gov/daac-bin/G3/gui.cg
i?instance_idMERRA_MONTH_2D
http//gdata1.sci.gsfc.nasa.gov/daac-bin/G3/gui.cg
i?instance_idMERRA_MONTH_3D
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What is to come for MERRA Giovanni?
Daily Data will be available in the future
Subsetting MERRA along CloudSat track
Example shows plotting of the vertical profile
for air temperature along a CloudSat track from
0000am - 100am
Inter-comparisons between MERRA and
Satellite/Model Data
Example shows plotting of MODIS Terra monthly and
MERRA monthly single level, native resolution
Cloud-Top Pressure
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Hands on case studies

• Case 1 Lat-lon map Time averaged ? Winter
  Precipitation
• Area ( 180W 180E, 50S-50N)
• Total precipitation ( in group Land surface
  diagnostics)
• Begin Date Jan 1979, End Date Feb 1979
• Lat-lon map, Time averaged
• Click Generate Visualization, to process and
  generate the image
• On the result page, modify min/max to ( 0,
  0.0003), or color palette,
• note that the value has been scaled on the plot
• Click Generate Visualization to re-generate the
  image
• Click on download data at the top
• Click on KMZ icon to display through GoogleEarth

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A-Train Example