An Update on GrADS

Brian Doty and Jennifer Adams

GrADS CapabilitiesGrADS is an interactive tool for the analysis and visualization of geoscience data• Open source and freely available

GrADS has 2 data models• 5-D gridded data• In situ (station data

GrADS can read all the standard data formats • Binary• BUFR• GRIB (versions 1 and 2)• HDF (versions 4 and 5) • NetCDF (versions 3 and 4)

Missing data handled consistently throughout

Expression syntax is flexible, compact, recursive

Programmable interface for scripting

Fast I/O and graphics

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GrADS is Used Worldwide

77,500 downloads February 2010 - Present

GrADS @ COLAHow does COLA benefit from GrADS? • Format neutralization facilitates COLA’s ”model agnostic” strategy• Collaboration expedited by script-sharing• Easy, format-independent metadata harvesting for COLA’s data management strategic plan• In-house expertise for immediate help and code changeso new and complex data sets o very high resolution datao optimization of scriptso beautification of published figures

How does GrADS benefit from COLA?• Feedback from scientists (deliberate and accidental)• Development needs are readily apparent• Pre-release testing of new features

Easy Multi-Model IntercomparisonError in July Mean Total Precipitation (in meters)

ECMWF IFS - TRMM

NOAA CFSv2 - TRMM NCAR CCSM4 - TRMM

Japan NICAM - TRMM

GrADS @ COLAHow does COLA benefit from GrADS? • Format neutralization facilitates COLA’s ”model agnostic” strategy• Collaboration expedited by script-sharing• Easy, format-independent metadata harvesting for COLA’s data management strategic plan• In-house expertise for immediate help and code changeso new and complex data sets o very high resolution datao optimization of scriptso beautification of published figures

How does GrADS benefit from COLA?• Feedback from scientists (deliberate and accidental)• Development needs are readily apparent• Pre-release testing of new features

GrADS 2.0.0 Highlights

Major changes to the core of GrADS:• Added 5th data dimension (targeted to ensembles)• Internal data handling in double precision• More consistent missing data handling• Very stable: bugs fixed, memory leaks patched

New data formats• GRIB2• HDF5• NetCDF4o Early adopter of compression features

GIS Interface• Read shapefiles• Output shapefiles, GeoTIFF, and KML

The New Shaded Contouring Algorithm

Station Data Shapefile from GrADS in ArcMap(Dressed up with Topography, Political Boundaries, and City Names)

OLR and Precip Data from GrADS in Google Earth

05Z 23May2009

An interactive, web-based system to display CPC products together with supplemental geographical data

Climate Prediction Center’s GIS Portal

What’s Next

New options for rendering the graphics• Use of Cairo library for X11, image, and hardcopy drawing• Old methods still available

Design of new data analysis capabilities• EOFs, Sorting, etc.• Internal/External operations on defined objects (defop)

• COLA has considerable expertise and experience in remote data analysis o Pioneered server-side analysis with GDSo Currently managing off-site computing at 3 remote centers

• Will mobile cloud-based computing change how we do our science work?

GrADS in the Cloud

Live Demo @ Poster Session Experimental prototype of GrADS running as a "cloud" service

Using GrADS in the new cloud computing paradigm