Data Access and Visualization of Model data at the GES DISC

D. Ostrenga1,3, H. Rui1,3, B. Vollmer1, B. DeShong1,3, G. Lei1,3, S. Shen1,2, P. Huwe1,3, C. Loeser1,3, M. Greene1,3, and D. Meyer1

1 NASA GES DISC2CSISS, George Mason University

3 Adnet Systems, Inc.

Outline

• Introduction• How do I get the Data?• Data Services • Applications• Conclusion• Future work• Links/information

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The GES DISC: Who We ARE

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The Goddard Earth Sciences Data and Information Services Center (GES DISC) is one of the 12 NASA EOSDIS DAACS that manage, archive and distributes the Earth science data as part of NASA’s Earth Science Data Systems Program. We provide the support for the archive and distribution of the data for multiple satellite sensors, ground measurements, field campaigns and models. These include Aqua AIRS, Aura HIRDLS/MLS/OMI, SORCE, TOMS, TOVS, TRMM, UARS, LDAS and MERRA/MERRA-2.

The archives total volume exceeds 1.5 Petabytes consisting of almost 95 million granules covering over 2500 public and restricted datasets.

Through various available services and tools, the GES DISC provides users with multi-sensor and model visual comparisons and data access via various tools and services through a number of projects crossing several disciplines.

Model Data at GES DISC

• The GES DISC provides support to two main modeling groups:– Global Modeling and Assimilation Office (GMAO)– Hydrological Sciences Laboratory (HSL)

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Types of support:• Archival of MERRA, MERRA-2, and FP-IT data • Archival of LDAS data• Provide documentation support:

• Writing user guides• Registering DOIs• Creating Data Interchange Format (DIFs) documents• Web content and interface development

• Develop Value Added Services• User Support• Metrics• Provide Ancillary Data Support

Model Data at GES DISC

GMAO Data

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GMAO data sets archived and distributed through GES DISC:

•The Second Modern Era Retrospective-analysis for Research and Applications (MERRA2)

•95 data products •Jan 1980 - present•Analysis and History•Instantaneous and Time averaged•1 hourly, 3 hourly, 6 hourly, Monthly and Diurnal•Resolution of 5/8 x 1/2 Degree

•Modern Era Retrospective-analysis for Research and Applications (MERRA)•65 Data Products

•Jan 1979 – Feb 2016•Three Groups: Analysis. Chemistry Forcing, and History•Instantaneous and Time averaged•1 hourly, 3 hourly, 6 hourly, Monthly and Diurnal•Resolutions: 1.25 x 1 Degree and 2/3 x 1/2 Degree

GMAO data sets archived and distributed through GES DISC (con’t):

• GEOS FP-IT - This is a restricted data set and needs approval from GMAO before it is disseminated.

• 29 Data Products • Version 5.12.4• 3 hourly, 1 hourly, • time averaged and instantaneous. • Individual files. • 28 unique data product subsets • 1 generated value-added data product generated and archived for the U of Montana

•MERRA along A-Train track subsets •4 products•Available through the web interface

GMAO Data (Cont)

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HSL Data

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HSL data sets archived and distributed through GES DISC:

• Data products from North America Land Data Assimilation System (NLDAS)• Jan 1979 to present• 1/8 degree grid spacing• CONUS, parts of Canada and Mexico

• Global Land Data Assimilation System (GLDAS)• Jan 1979 to the present at 1 degree • Jan 2000 to the present at 0.25 degree

• Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS) –

• Jan 1982 to the present • 0.1 and 0.25 degree for Eastern Africa, Southern Africa, and Western Africa.

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Redesigned interfacehttp://disc.gsfc.nasa.gov

More efficient and user friendly design to find the information and data you need with new capabilities to search by mission, discipline, and other key information.

The GES DISC Web Interface

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Accessibility from the Start!

• Direct data product search and mission search

• Link to services from the Gateway

• Find related documentation

How Do I Find What I Need?

How Do I Find What I Need?

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• Faceted Filter• Measurement• Source• Discipline• Temporal

Resolution• Spatial

Resolution, etc

• Product Listing

• Product Information

The search result is a product listing of all availableProducts with the metadata tagged with your keyword. A more specific keyword will yield less more accurateresults.

How Do I Find What I Need?

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• Product description

• Documentation

• Data Access Methods

Click on the data product name will bring the user to the Data Set Landing Page.

Data and Services Facilitate Research and Applications

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Web Interface• Web interface to data products and services• Search and Download Mechanisms• Data Set landing pages

GDS – GrADS Data Server OPeNDAP - Open-source Project for a Network Data Access Protocol

OTF Data Subsetter – Parameter, Spatial, Time, Vertical, Mean averaging, formatconversion and regridding.

Giovanni – On-line Data Visualization and Analysis Tool which we have monthlyand daily instances.

HTTPS direct online access – Direct anonymous HTTPS accessSubscriptions – to mission teams and other “power” usersValue-added generated data products– for ex, Montana subset for UMT

SSW - Simple Subset Wizard allows subset and download of the data with obs datasets

Mirador and Simple Subset Wizard

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Mirador supports keyword, time span, and locationsearches. Keywords can be parameter names; science discipline areas (such as oceans); instrument, sensor, or model names; or data product short names. There is also an event search capability. Miradoris supported by a geographic feature Gazetteer.

Use the Simple SubsetWizard (SSW) to submitsubset requests for hundreds ofdata sets across multiple datacenters from a single unifiedinterface.

OPeNDAP and GDS

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The data are also available via the OPeNDAP the and GrADS Data Server(GDS) protocols. Some example of the functionalities you can perform are:1. Subset single point locations2. Visualize the data over a time series3. Subset by variables and time.

Use GrADS or OPeNDAP for single point variable subset to produce time series, great for

studying winds!

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OPeNDAP and GDS

HowTo’s for OPeNDAP and GDS:https://uui.gesdisc.eosdis.nasa.gov/uui/information/howto?title=how%20to%20obtain%20spatially%20subsetted%20time%20series%20data%20in%20one%20netcdf%20file%20via%20gds

https://uui.gesdisc.eosdis.nasa.gov/uui/information/howto?title=how%20to%20obtain%20spatial%20subsetted%20time%20series%20in%20ascii%20format%20via%20gds

What is Giovanni?Giovanni is a Web-based application developed by the GES DISC that provides a simple andeasy way to visualize, analyze, and access vast amounts of Earth science remote sensing andmodel data.

Select spatial area, parameters, and timerange. For 3D parameters, select verticallevels. Then pick a visualization.

Giovanni is Easy to UseThe Giovanni provides access to atmospheric, hydrological, environmental, and oceans data from multiple satellites, in situ observations, and models with well over 1000 parameters.

Giovanni

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Visualization Functions: Single time or time averaged Lon-Lat Map Single point or area averaged time series Animation Interannual variation analysis User defined climatology Histogram Vertical profile, or crossmap Scatter Plot Correlation Map Difference between two variables

Download Features: Image map (png, geotiff, KMZ) Image map data (netCDF) Time series plot (png) Time series data (CVS, netCDF) Image map or time series within a shapefile, such as country, watershed Lineage for getting intermediate data

Giovanni (Cont)

Visualize and analyze large volumes of data …

… with only a few mouse clicks.

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Giovanni (Cont)

L3/4 Subsetter and Regridder

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L3/4 Subsetter and RegridderOur most popular service that allows users to create subsets of the model data to reduce download volume and get only what a user needs.

• Spatial Subsetting• Temporal Search• Temporal Subsetting• Variable Subsetting• Vertical Subsetting• Calculate Daily Means• Regrid to another format• Re-Format the Output

…..The result is a list of subsetted granules. You have the option to download a list of subsetting URLs to invoke with curl or wget to automate a bulk download.

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L3/4 Subsetter and Regridder

Demonstration

• Web Interface, Giovanni and L3/4 Subsetterand Regridder

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Supporting Applications

Recent activities have been under way for creating new value-added products, Data Lists, and subsettingservices to support the following applications:• Renewable Energy• Extreme Weather• Air Quality

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Applications

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Left: MERRA-2 assimilated hourly column dust mass density, the dust travels eastward from Asia across the Pacific reaching California and even Maryland in about 6-10 days.

2001.04.04 00Z

2001.04.06 00Z

2001.04.08 00Z

2001.04.10 00Z

2001.04.12 00Z

2001.04.14 00Z

Example Dust Storm from Asia to North America

Above: True color image from MODIS, the famous “Perfect Dust Storm” on April 7 2001 over Northeast China. Courtesy: http://earthobservatory.nasa.gov/IOTD/view.php?id=8341)

Applications (Cont)

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Monthly Climatology of Aerosols(Base period: 1980-2014)

Example monthly climatology: aerosol scattering AOT at 550 nm and Dust wet deposition for Jan, Apr, Jul, and Oct, respectively. The average is made for 35 years period from 1980-2014.

The dust depositions are available as dry and wet at five dust particle size bins in the range from 0.1 to 10 (μm) in radius.

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Monthly Climatology of Aerosols(Base period: 1980-2014)

Applications (Cont)

Time series of global mean dust deposition for April (blue line) and July (black line) from 1980 to 2014. Both Wet and Dry dust deposition show systematic difference before and after about year 2000. More studies are needed to investigate if it is a real signal or the artifact due to different input satellite data.

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Animation of hourly precipitation (10Z August 26 ~ 12Z August 29, 2011) from NLDAS-2 Primary Forcing product.

Area-averaged time series of NLDAS-2 hourly precipitation for the U.S. East Coast.

Animation of hourly soil moisture (10Z August 26 ~ 12Z August 29, 2011) from the NLDAS-2 Mosaic model.

Applications (Cont)

Future Work

• Value-added products (e.g. renewable energy focus)• Additional customized data output such as along-path

subset and single point spatial subset service• More visualization capabilities • Optimizing file structure for time series

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Conclusion

• MERRA, MERRA-2, LDAS data are available at the NASA GES DISC

• Other global datasets (TRMM, NLDAS, GLDAS, MERRA, etc.) also available

• Data services to facilitate data access and evaluation (UUI, Giovanni, SSW, etc.)

• Applications (under development) to support various activities

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Information

• Search and download MERRA-2 data: http://disc.gsfc.nasa.gov

• Online visualization and analysis: http://giovanni.gsfc.nasa.gov or Google search “NASA giovanni”

• Comments and suggestions: – gsfc-help-disc@lists.nasa.gov– Dana Ostrenga dana.Ostrenga@nasa.gov

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