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NERSC Honored for HPC Innovations Excellence

20th Century Reanalysis Project Support Cited

June 20, 2011

Linda Vu,, +1 510 486 2402


The Department of Energy’s National Energy Research Scientific Computing Center (NERSC) has been honored with an HPC Innovation Excellence Award for providing supercomputing, storage, and service support to the 20th Century Reanalysis Project—a collaboration of the University of Colorado, National Oceanic and Atmospheric Administration (NOAA), the Atmospheric Circulation Reconstructions over the Earth Initiative, and 30 international organizations.

Led by University of Colorado climatologists Gilbert Compo and Prashant Sardeshmukh, and NOAA meteorologist Jeffrey Whitaker, the Project uses supercomputers to reconstruct global historical weather maps from 1871 to present day.  This dataset helps the science community put current weather extremes in a historical perspective, determine how extremes are changing, and validate computer climate models. The winners were announced this morning at the 2011 International Supercomputing Conference in Hamburg, Germany. The award was created by International Data Corporation (IDC) to recognize noteworthy achievements by users of high performance computing technologies.

"The 20th Century Reanalysis project is a great example of how dedicated supercomputing time and technical support can significantly advance research in an area that has significant impact on our lives," said NERSC Director Kathy Yelick.

The project’s dataset is currently the longest comprehensive record of past weather variability. The dataset is unique in providing 56 different reconstructions of the global weather map from the surface of the Earth to the level of the jet stream every six hours from 1871 to the present. The mean of the 56 maps represents the best guess at the weather, and the standard deviation provides an estimate of the uncertainty in the reconstruction. These data offer valuable insights into historic extreme weather events such as the 1930s Dust Bowl, the deadly 1922 “Knickerbocker storm,” and a variety of El Niño episodes. It also provides the first long-term estimates of variability in the global troposphere—the lowest portion of the earth’s atmosphere that contains approximately 75 percent of the atmosphere’s mass and 99 percent of water vapor and aerosols.

"Producing this huge dataset required an international effort to collate historical barometric pressure observations and recordings from sources as diverse as 19th century sea captains, turn of the century explorers and medical doctors, all pieced together using some of the world's most powerful supercomputers at the US Department Energy's National Energy Research Scientific Computing Center in California and the Oak Ridge Leadership Computing Facility in Tennessee," says Compo.

Over the years, the 20th Century Reanalysis project has used more than 16 million computing hours at NERSC. The center’s user consultants have also helped these researchers achieve higher throughput by simplifying their data handling and creating script solutions to help them port, tune and debug their applications.

Additionally, NERSC staff have provided significant support to ensure that portions of the 20th Century Reanalysis dataset were successfully transferred to NERSC from supercomputing centers at the National Oceanic and Atmospheric Administration (NOAA), National Center for Atmospheric Research (NCAR) and Oak Ridge Leadership Computing Facility (OCLF) where the team has computed over the years.

NERSC is currently storing the master copy of the project’s entire dataset.

Selected variables with all 56 estimates from this dataset are currently available to researchers around the globe through the 20th Century Reanalysis Project Ensemble Gateway hosted at NERSC. The ensemble mean and uncertainty for many variables are available through the NOAA Earth System Research Laboratory and NCAR. So far portions of the dataset have been cited in four papers published by Compo’s team, and 11 other papers published by researchers who have accessed this data through the NERSC gateway, NOAA, or NCAR.

In addition to Compo, Sardeshmukh and Whitaker, there are 24 other co-principal investigators on the project.

»Read more about 20th Century Reanalysis Project.

»Read more about the HPC Innovation Excellence Award.

About NERSC and Berkeley Lab
The National Energy Research Scientific Computing Center (NERSC) is the primary high-performance computing facility for scientific research sponsored by the U.S. Department of Energy's Office of Science. Located at Lawrence Berkeley National Laboratory, the NERSC Center serves more than 4,000 scientists at national laboratories and universities researching a wide range of problems in combustion, climate modeling, fusion energy, materials science, physics, chemistry, computational biology, and other disciplines. Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California for the U.S. DOE Office of Science. »Learn more about computing sciences at Berkeley Lab.