Polar DAAC User Working Group (PoDAG XII) Meeting

-- K. Stefffen, PoDAG Chariman, University of Colorado, Boulder
-- D. Bromwich, PoDAG Co-chair, Ohio State University
-- R. Weaver, NSIDC DAAC Manager, University of Colorado, Boulder

The 12th meeting of the National Snow and Ice Data Center (NSIDC) Polar DAAC User Working Group (PoDAG) was held June 17-18, 1997 in Boulder, Colorado. Following are the recommendations, action items, and abbreviated minutes of this meeting. Please visit the PoDAG home page at http://www-nsidc.colorado.edu/NASA/PODAG/ for further information. Some of the presentations given at PoDAG XII are linked to this webpage.

Recommendations

Near-Real-Time Ice and Snow Extent Product

The Near-Real-Time Ice and Snow Extent (NISE) product generation, which uses a multifrequency, multipolarization passive microwave algorithm, is supported by the PoDAG members; however, archiving these products is not recommended.

Generation of Microwave-Based Permafrost Extent Maps

PoDAG does not recommend pursuing research and data production on permafrost extent at the NSIDC DAAC at this time. The recommendation may be considered at a later time, with more-promising algorithms. Use of the DAAC resources rather to support ongoing and future field programs in data archiving (e.g., PARCA, SHEBA, and others) is recommended.

K-12 Outreach

PoDAG does strongly support and praise the effort of the NSIDC DAAC in K-12 outreach and curriculum development. However, given the budget constraints for the DAACs in the coming years, use of the DAAC Full Time Equivalents (FTEs) to support this effort is not recommended. Support for K-12 Outreach should be leveraged from special education grants (e.g., from NASA HQ, GLOBE, NSF, and others).

MODIS Snow and Sea-Ice Products

MODIS snow and sea-ice products should be processed in EASE-Grid projection, in addition to the sinusoidal grid. MODIS Level 2 Data should be sent without delay from the GSFC DAAC to the NSIDC DAAC for snow and ice product generation. This is crucial for those in the operational communities who need products within one day. NSIDC believes it can deliver these browse products within this time frame.

MODIS Snow and Ice Production Mask

PoDAG recommends that the current MODIS snow and ice production mask be extended from 40 degrees North and South, to include all areas on the Earth with seasonal snow cover and ice cover.

(1) Update on NSIDC activities since PoDAG XI, by Ron Weaver.

• Accomplishments Data Services
  1. Permafrost/frozen ground assessment completed. Report by Tingjun Zhang given in item 12.
  2. NISE product to be provided to EOS MISR and CERES instrument teams. Report by Anne Nolin in item 7.
  3. Greenland synthetic aperture radar (SAR) mosaic completed.
  4. AMSR data from ADEOS II to be archived and distributed by NSIDC.
  5. Arctic and Antarctic Research Institute (AARI, Russia) sea-ice data in EASE-Grid to be distributed by ftp.
  6. F11 brightness temperature and sea-ice concentration grid CD-ROM processing completed through September 1995. Daily and monthly grids available via ftp. F-13 brightness temperature grid CD-ROM processing completed through December 1996. Sea-ice concentrations available via ftp through December 1996.
  7. Special Publication Number 5 on F11/F13 intercomparison nearing completion.
  8. EASE-Grid processing of passive micro-wave global brightness temperatures through November 1992.
  9. Comiso bootstrap algorithm processing under way.
  10. 12,000 AVHRR scenes received and processed.
  11. Various intra-DAAC support activities completed.
  12. Transfer of data from MSFC to NSIDC completed.

• Major Accomplishments Systems Engineering
  1. Data Request Tracking Software online.
  2. Computer room modifications completed.
  3. EOSDIS Core System Release B Testbed hardware and software installed.
  4. Release B.0 hardware for EOSDIS Core System installed.
  5. Staffing increased for EOSDIS Core System activities.

• Major Accomplishments Data Support
  1. Richard Armstrong will collaborate with the EOS AMSR instrument team on snow-cover study.
  2. Anne Nolin will work on a snow-cover reflectance assessment in conjunction with the EOS MISR instrument team.

(2) Role and Charter of PoDAG

• PoDAG was originally tasked to provide scientific guidance to the NSIDC DAAC and to the EOSDIS Project regarding such issues as the usefulness and priorities of individual data sets and the addition of new data sets.

• NASA Headquarters provided guidance and selected new PoDAG members. NSIDC now proposes new PoDAG members.

• PoDAG now reports to Skip Reber, the acting EOSDIS Project Scientist.

• Support for PoDAG participation costs needs clarification. NSIDC may undertake to fund PoDAG participation to a limited extent.

• Feedback from PoDAG to NSIDC should, in part, involve the development of a long-term plan.

(3) Global Sea-Ice Data Set Don Cavalieri

• A 17-year global sea-ice data set at GSFC that merges SMMR and SSM/I data sets (10/78-9/95) is approaching completion. A NASA Technical Memorandum describing the processing is being prepared.

(4) Passive Microwave Products Jim Maslanik

• Processing of SSM/I sea-ice concentrations through December 1996 was completed with NASA Team and Comiso bootstrap algorithms. New products planned are the global sea-ice data set (see item 3), ice concentrations based on the corrected Comiso bootstrap algorithm, and sea-ice melt onset product based on research by Mark Anderson. Additional publications being prepared are new documentation on SSM/I brightness temperatures and two technical notes on inter-calibration and data corrections. The desirability of distributing multiple sea-ice data sets was discussed.

Previous action items were also considered. The effects of data set intercomparisons on derived sea-ice concentrations were generally small (see item 5). Additional masks to be provided by SSM/I processing are for land contamination and for open ocean weather effects.

(5) Sea-Ice Concentration Product Intercomparison Julienne Stroeve

• The impact of any adjustments to SMMR-, F8-, F11-, and F13-derived sea ice concentrations to improve consistency between different data sets would be only a few percent.

(6) SSM/I Pathfinder EASE-Grid Processing Mary-Jo Brodzik and Richard Armstrong

• Processing of F8 data should be completed by September 1997. F11 and F13 data processing is scheduled to be finished by October 1998.

• Richard Armstrong discussed the Northern Hemisphere product, which combines NOAA weekly snow cover on land with the passive microwave depiction of sea-ice concentration covering 1978 to 1995 on the EASE-Grid. He suggested the formation of an ad hoc working group to identify a snow-water-equivalent algorithm for application to satellite passive microwave data.

(7) NISE Product Anne Nolin

• This product has been proposed to support the processing of data from EOS instruments. The resolution will be 25 km globally, and the delay will be two-to-three days after real-time. Masks will be provided for snow extent and ice caps on land and sea-ice extent over the ocean. Discussion indicated that this experimental SSM/I product should be produced in an operational mode only, and not archived as a research quality data set.

(8) Tools for Use of Multiple Polar Pathfinder Data Sets Ron Weaver

• Six weeks is required for a senior programmer to write the necessary software for the Polar Pathfinder data sets. However, the participants in the Polar Pathfinder project have not yet decided on a common data format. Further more, some uncertainties with the EOS HDF data format still need to be resolved. The recommendation was to revisit this question at the next PoDAG meeting. For more information about the Polar Pathfinder products, please visit the Pathfinder webpage at http://www-nsidc.colorado.edu/NASA/POLAR_PATHFINDERS/.

(9) EOS Cryospheric Working Group Barry Goodison

• A new chairman has not yet been identified, but an individual who is part of one of the EOS interdisciplinary science projects is interested. (Addendum: It is now official that Dr. Robert Crane, Penn. State University, is the new CWG chair. We all wish Rob well in his new task.)

(10) Update on Global Land Ice Monitoring from Space (GLIMS)

• The goal is to describe the temporal evolution of all ice extent on land for the purpose of studying climate change. It started with the EOS ASTER instrument, but has evolved to incorporate all appropriate sensors. Tasks involved are much larger than can be handled by a single group, so regional centers have been established. Some progress has been achieved on algorithm development, but much more effort is needed.

(11) Update on AVHRR Polar Pathfinder Data Processing Ted Scambos

• Almost three years of 5-km products have so far been produced. One-km products are being produced for specific area and/or process studies. A cloud mask will be provided, based primarily on cloud motion detection. Distribution is planned to start after mid-1998.

(12) Role of Remote-Sensing Data in Permafrost and Frozen Ground Studies Tingjun Zhang

NSIDC reviewed a possible new research activity in support of EOSDIS data distribution to be housed at the data center. The application of passive and active satellite microwave observations to detect the thawing and freezing of snow-free ground was summarized. The primary unresolved problem is the need to determine whether the ground is free of snow. Also, the depth of freezing is a key variable for polar hydrological considerations and, in order to obtain it, information in addition to remote-sensing observations is required. Further studies of this application's feasibility are needed.

(13) Workshop on New Approaches to Sea-Ice Observations Ron Weaver and Koni Steffen

• The two-day workshop is designed to assess possible new avenues for sea-ice monitoring during the EOS time period by making use of current and new sensors in combination with process models. The main focus is on data assimilation and how it can advance current remote sensing for sea-ice monitoring on regional and global scales. The proposed date is early December 1997, just prior to the American Geophysical Union Fall Meeting in San Francisco. A draft letter of invitation was circulated. (Addendum: This Workshop was held in Boulder on December 3-5. The report will be distributed in the first quarter of 1998.)

(14) Educational Outreach David McGinnis and Brenton Burnett

• The K-12 educational initiative of the National Science Foundation's Arctic System Science (ARCSS) program, called Advancing Arctic Research into the Classroom (AARC), was discussed. Some basic observations were that many schools are not Internet-ready, data available are confusing, and students and teachers need tailored information. A developed curriculum with inquiry-based learning is the desirable approach. Both online (World Wide Web) and CD-ROM approaches are needed. Curricula must be built around available online data sets (NASA and NSF), which, in turn, must be adapted for use in the classroom. The course developers will seek funding from a variety of sources.

(15) MODIS Snow and Sea-Ice Products Robert Wolfe

• The processing of the data stream from the EOS MODIS instrument was discussed. Coordination of data processing between GSFC and NSIDC was reviewed, as was the need to have global depiction of all land ice, not just that poleward of 40 degrees latitude. Further consideration is required as to the spatial resolution needed for MODIS products.