On Monday, 11 July from 3:00 p.m. through Wednesday, 13 July until 5:00 p.m. (USA Mountain Time), NSIDC data distribution, services, and Web site will be unavailable to accommodate a major upgrade to our data center. We apologize for any inconvenience this may cause you. Need to talk to us? You can always contact our friendly User Services Office at firstname.lastname@example.org or + 1 303.492.6199.
In this Issue
GLOBAL CHANGE RESEARCH
PRODUCTS AND SERVICES
ARCTIC SYSTEM SCIENCE (ARCSS)
DEFENSE METEOROLOGICAL SATELLITE PROGRAM (DMSP)
ONGOING RESEARCH ACTIVITIES
The Arctic is known to be a region where the consequences of global environmental changes, notably climate changes, will be particularly severe. The currently existing global climate models all share the common feature of a significantly larger rise in mean surface temperatures at high northern latitudes than elsewhere. This is particularly disturbing since a number of feedback processes, involving a shrinking sea ice cover or the release of greenhouse gases from thawing permafrost, are believed to enhance any initial warming. This will have a bearing on the rest of the world and underlines the importance of high-latitude processes for the state of the global system.
It is these considerations that have led to a growing awareness that global change research cannot leave out the polar regions. Consequently, the International Geosphere-Biosphere Program (IGBP) through its START-Initiative (SysTem for Analysis, Research and Training) and the World Climate Research Program (WCRP) through its recently launched Arctic Climate System Study (ACSYS) have acknowledged these facts.
Right from the start, the International Arctic Science Committee (IASC) and its member countries recognized the importance of global change research as a major thrust of the newly formed organization. One of the first working groups initiated by IASC was the Global Change Working Group under the chairmanship of Gunter Weller (University of Alaska). During a first workshop in Reykjavik, Iceland, in April 1992, the Working Group outlined the possible scope of an Arctic Global Change Research Program (AGCRP). During the subsequent IASC council meeting, also in Reykjavik, it was felt that some supporting structure was needed in order to get the AGCRP off the ground. Finland offered to host what was to become the IASC Global Change Program Office (IASC-GCPO). During their recent meeting in Abisko, Sweden, the Council decided to accept this offer and to charge the Arctic Centre at the University of Lapland in Rovaniemi, Finland, with the task of implementing the IASC-GCPO. Headed by Manfred Lange, the Office will primarily support and implement the scientific initiatives and decisions of the Global Change Working Group. It will also be a contact point between the Group and other international global change research programs active in or with an interest in the Arctic.
The Scientific Committee on Antarctic Research (SCAR), also under the leadership of Gunter Weller, has worked out a plan for global change research in Antarctica. It is hoped that both initiatives will eventually be merged in the future in order to join forces in what is bound to become a very important component of research on global environmental changes.
For further information please contact: Dr. Manfred Lange, Global Change Program Office, Arctic Centre, P.O. Box 122, SF-961061, Rovaniemi, Finland or at +358-324-771; fax: +358-60-324-760.
Beginning 1 October 1993, NSIDC will have available for distribution the Historical Arctic Rawinsonde Archive (HARA) on 3 CD-ROM volumes. Containing over 1.2 million vertical soundings of temperature, pressure, humidity and wind, this set represents all available rawinsonde ascents from Arctic land stations poleward of 65 degrees. North from the beginning of record through 1987. For most stations the record begins in 1958, a few begin in 1947 or 1948. The data are one file per year per station. Coverage is relatively uniform, except in the interior of Greenland. Typically 20 to 40 levels are available in each sounding. Documentation is provided on the CD-ROM volumes, and in hard copy (NSIDC Special Report 2, 1992). Software (Fortran and C) is provided on the CD-ROM volumes to retrieve a subset of the sounding data. Data for 1988 to 1990, and monthly averaged data, will be prepared for CD-ROM volume 4 during 1993. Sounding data were obtained from the National Center for Atmospheric Research (NCAR), Boulder, Colorado, and the National Climatic Data Center (NCDC) of NOAA in Asheville, North Carolina. When the CD-ROM stock is exhausted, we will determine whether to re-print the discs or to provide data via anonymous ftp, depending on feedback we receive from the science community.
The HARA CD-ROM set is being distributed at no charge. Request copies from NSIDC User Services (Michelle Holm, Internet: email@example.com. or (303) 492-2366.)
Volume 2 of SSM/I Ice Concentrations (1990-1991) is being mailed during the week of 20 September to all registered SSM/I CD-ROM users. Watch for your copy in the mail, and let us hear from you if there are questions, problems, comments, suggestions, or any other feedback you would like us to hear. Also, a reminder that we would like to receive one reprint of your papers or other publications that cite the use of data we have distributed, particularly the SSM/I CD-ROM product. The resulting bibliography will help us determine the level of use of the data product, which helps to justify continued funding for distribution of data products in support of basic science. Thank you!
During October, NSIDC expects to complete Version 1 of the User's Guide for Nimbus-7 SMMR Polar Radiances CD-ROMs. This document has been in an extended development and review process in order to provide the proper amount of information in a format that is helpful to users. The User's Guide supplements the SMMR Atlas [Gloersen, P.; Campbell, W.J.; Cavalieri, D.J.; Comiso, J.C.; Parkinson, C.L.; and Zwally, H.J. Arctic and Antarctic Sea Ice, 1978 to 1987: Satellite Passive Microwave Observations, NASA SP-522, 1992]. NSIDC will automatically distribute the User's Guide to all recipients of the 12 SMMR CD-ROM volumes. Details on availability of the SMMR Atlas will be announced shortly.
The Navy - NOAA Joint Ice Center project to quality-check and correct the 1972 to 1990 Arctic and Antarctic weekly sea ice data base is underway. We are unable to provide a status report at this time, but we expect an update (and significant progress) in time for the next newsletter issue.
If you are using or have used these data, and have not received the April 1993 notification of data errors, please contact NSIDC User Services for information on the extent and type of errors in the data base.
Missing SMMR Data
Volume 9 of the SMMR Polar Radiances CD-ROM is missing data for the dates October 6, 1981, through December 25, 1981, for all channels. The files exist on the CD-ROM but they do not contain data.
The data for the missing days will be reprocessed and volume 9 will be redistributed with the corrected files to NSIDC's mailing list of SMMR CD-ROM recipients. The distribution date has not been determined, and is dependent on the length of time required to reprocess the data, among other factors.
In June 1992, NSIDC distributed a questionnaire to approximately 350 recipients of the CD-ROM SSM/I Sea Ice Concentration Grids, Volume 1, Revision 1;. The data contained on the CD-ROM were packaged in the Hierarchical Data Format, an EOSDIS Version 0 standard for data distribution. The purpose of the questionnaire was to obtain an indication of the appeal of HDF as a distribution format to the user community served by NSIDC. The results of the survey were compiled by Matt Cross and are summarized in the following tables.
Are you now using (or planning to use) the SSM/I sea ice concentration grids on CD-ROM?
What type of system will be used?
|PC-IBM or clone||NEC-PC||Macintosh||UNIX||DEC-VMS||IBM Mainframe||SUN||SUN SparcStation||SGI (indigo)|
If you have used HDF tools to display and analyze data, which tools have you used?
|XImage||XDataSlice||DataScope||Image||PCShow||Spyglass||IMDISP||GKS||PUWAVE||NCSA Layout||GET SSM\I|
What additional functions would you like to see added to the HDF tools?
Which statement best describes your level of familiarity with HDF at the time you began using HDF data sets and tools?
|No prior knowledge||Had heard about HDF||Had used HDF formatted|
|Am an expert|
user of HDF
With what other standard data formats are you familiar?
CCT, VICAR, PDS LABELED,
FITS, Miami DSP, TIF (2), GIF,
IMDISP, ARC/INFO, AutoCAD
Are there other data sets you would be interested in receiving in HDF format?
Contact NSIDC User Services for additional details regarding the results of the HDF survey. (Michelle Holm, Internet: firstname.lastname@example.org or (303) 492-2366.)
There are several data projects in the works at NSIDC targeted for the Arctic System Science (ARCSS) research community. We have been telling you that these products are under development and due soon, and at newsletter press time that news has not changed. In the next issue of NSIDC Notes, look for availability announcements for one or more of these Arctic data products.
If you have a requirement for Arctic data that you have been unable to locate or obtain, or an idea for a new Arctic data product, please contact NSIDC User Services.
Development of the DMSP Digital Data Archive at the NOAA/National Geophysical Data Center (NGDC) continues. NSIDC and NGDC are jointly involved in the effort to archive all U.S. Air Force Defense Meteorological Satellite Program (DMSP) data in digital form. NSIDC is involved in much of the design and development work, and will provide user services for data related to the climate-cryosphere system once the archive is fully functional. Funding for this effort is from the Department of Defense, NOAA and NASA.
Though data from the archive are not available yet, we expect to beginprocessing data during October 1993. The data which have been copied to 8 mmtape by Air Force Global Weather Central on an experimental basis since March1992 will also be processed beginning later this fall.
Work at NSIDC is currently focused on the X-window-based Graphical User Interface (GUI) for searching and browsing data. Prototype software modules for several parts of this system are now being tested. Searches of the satellite data base inventories can be based on several types of input criteria (latitude/longitude coordinates for specific geographic points or areas, day versus night coverage [or limited to images with a specified percent of each], % moon, time of day, sensor type(s), spectral band, and resolution). Search output granules will be in the form of orbit files that meet these criteria. Selecting a granule will result in the display of other GUI modules. These include a browse image viewing tool, and a graphical orbit mapping tool that displays a map of the world, in several map projection options, with overlays of the orbit and area covered by the image. Political and geographical overlays can be added. The browse images can be adjusted to enhance brightness and contrast. At first this system will be used by in-house (NSIDC and NGDC) user services staff, but will later be adapted to serve remote data queries from outside on- line users.
For more information, contact Greg Scharfen, Internet: email@example.com or (303) 492-6197.
NSIDC has received funding for the 1-km Polar AVHRR project, which is intended to archive and generate products from a bi-polar collection of 1-km HRPT and LAC AVHRR imagery. Initial ingest and archiving of data from the McMurdo and Palmer receiving stations and a group of northern HRPT stations, as well as LAC coverage of both poles, is currently underway. The sources of the data are a polar subset of the Global Land 1-km AVHRR Data Set, currently collected by the Eros Data Center (EDC), and Antarctic 1-km HRPT AVHRR data from the Scripps Institution. Combined, these two data sets will provide nearly complete coverage of both poles; sea ice, land ice, and polar lands at nearly 1-km resolution, and for all 5 channels of the AVHRR sensor. The effort is in response to the stated highest-priority satellite data requirements from the Polar DAAC User Working Group (PODAG), and to numerous requests from the user community at large.
The archive contains data starting from April 1, 1992, for the Antarctic HRPT stations, and from August 1, 1993, for the north polar stations. NSIDC intends to pursue continuing the data collection through 1994 and beyond. Funding (from NASA) has been approved for data ingest and initial processing beginning August 1 of this year through the end of the calendar year; follow-on funding for 1994 is currently under consideration.
Users will be able to request 'raw' image data consisting of unprocessed, uncalibrated data as well as derived products such as georegistered or calibrated images, and, eventually, image maps of derived products such as snow surface temperature. NSIDC hopes to be able to respond to some requests from the polar science community for the raw image data before the end of the year.
For more information contact: Ted Scambos, Internet: firstname.lastname@example.org or (303) 492-1113.
NSIDC has begun providing interested users with radar altimetry data for user-requested, limited, areas of the polar ice sheets from the SEASAT, GEOSAT, and GEOSAT ERM missions. Access to the satellite radar altimetry data sets, which reside at NASA Goddard Space Flight Center, is provided through remote login from a workstation at NSIDC. Data types available in the NASA data set are gridded elevations, ice data records, and raw waveform data for the GEOS, SEASAT GEOSAT Mission, and GM Exact Report Mission, of Greenland and Antarctic land-ice regions. NSIDC also expects to begin testing of CD-ROMs containing the altimetry data this year. This medium will allow us to provide more general distribution of altimetry data to interested users. ERS-1 altimetry data are expected to be included in the archive at NASA beginning in the next few months, although CD-ROMs containing ERS-1 data are not expected in 1993.
For more information contact: Ted Scambos, Internet: email@example.com or (303) 492-1113.
GD-25, Snow Watch '92 and Workshop on Cryospheric Data Rescue and Access, has gone to the printer. It will be ready for distribution in October. This report contains the proceedings and recommendations of two workshops: