Community Newsletter
Winter 1996

Table of Contents

Unidata: Reaching Out

by Dave Fulker, Unidata Program Director

Last September, in a meeting of the Policy Committee at National Science Foundation (NSF) headquarters, NSF personnel expressed an interest in having Unidata extend its program to more disciplines within the geosciences and perhaps beyond. To date, the program has been funded by the Atmospheric Sciences Division (ATM) of NSF and has focused largely on providing data and services for the atmospheric-science community. NSF is interested in supporting interdisciplinary research and is looking for ways to integrate the research and education functions of universities. They believe that opportunities and new enabling technologies now exist to foster interdisciplinary research and education, and that these activities will strengthen science and produce fundamental new knowledge. We were pleased to be told that ATM sees the Unidata Program--which makes no distinction between research and education and which emphasizes the use or development of enabling technologies--as a model for how this can be achieved.

Both the Unidata Policy Committee and NSF believe that some of Unidata's systems may be of interest to other geosciences. In addition, the exchange and dialog between the atmospheric sciences and other disciplines could benefit both groups. If an outreach program is successful, it might broaden the support base for the Unidata program.

In an effort to evaluate whether other disciplines are indeed interested in Unidata systems, and what form this interest takes, the Unidata Program has sponsored a series of forums. Two of these forums were held at American Geophysical Union (AGU) meetings: the first at the general fall meeting (December) in San Francisco and the second at the AGU February Ocean Sciences meeting in San Diego. We also held a planning forum at this year's American Meteorological Society meeting in Atlanta.

In the course of these meetings, several interesting facts emerged:

  1. While Unidata is not well known outside the atmospheric sciences, a number of disciplines use Unidata's netCDF for data storage.

  2. Few other geosciences are traditionally as dependent on real-time data as is meteorology. However, some disciplines--among them, hydrology, seismology, oceanography, and atmospheric chemistry --appear to be interested in having access to these data.

  3. Within the atmospheric-sciences community there is considerable interest in acquiring less traditional data. Categories mentioned include soil-moisture and river-flow data; oceanographic information; air-pollution and other air-chemistry data; EOSDIS; and GIS data.

  4. Unbeknownst to either NSF or the Unidata Program Center (UPC), Unidata participants have already been using Unidata systems to collaborate with colleagues in other disciplines.
In discussions within the Unidata Users Committee and at the AMS planning forum, Unidata participants expressed concerns that reaching out to other disciplines would entail a reduction of services to the atmospheric sciences community. As several participants remarked, there is still a lot of work that Unidata could do for the atmospheric sciences alone.

Here at the UPC, we're wrestling with the implications of what we've learned from the forums. Are there disciplines with natural affinities for the Unidata community? If so, how can these affinities be capitalized upon? Can Unidata's outreach efforts be undertaken in a manner that benefits the existing Unidata community?

But the most important outcome is the discovery that Unidata participants are already engaged in interdisciplinary collaborations. The key to how Unidata might best proceed may lie with those who are already collaborating with others. If you are one of these people, please contact me, Ben Domenico (ben@unidata.ucar.edu), or Linda Miller (lmiller@unidata.ucar.edu). We'd like to know more about how these collaborations are working.

The New GOES Satellites: More than Just Pretty Pictures

by Melanie Wetzel, Desert Research Institute at the University of Nevada-Reno and Paul Ruscher, Florida State University

In April 1994, NASA launched the first in a new generation of Earth-observing satellites, to be called GOES I through GOES M. Each satellite in the series carries two major instruments: a five-channel imager and a nineteen-channel sounder. The imager acquires high-resolution visible and infrared data. The sounder can be used to retrieve temperature and moisture profiles of the atmosphere as well as other parameters. Both the instruments have higher spatial resolutions and improved signal-to-noise ratios than similar instruments on previous satellites.

These geostationary meteorological satellites also introduce two new features. The first, flexible scanning, allows small-area imaging that lets meteorologists focus on localized weather trouble spots to improve short-term forecasts and nowcasts. The second feature, simultaneous and independent imaging and sounding, allows weather forecasters to use data from both instruments to increase the accuracy of their analyses and forecasts.

The satellites provide more precise brightness temperatures due to improved onboard calibration, with noise levels reduced significantly from prior GOES instruments. Major enhancements to the Earth-observation capabilities include routine multispectral imaging of the contiguous US (CONUS) at 15-minute intervals, with capabilities for regional coverage of severe weather events as frequently as once every minute. Furthermore, the images are noticeably sharper than before because of improved quantization in the visible band and the improved signal-to-noise ratio and higher spatial resolution in the infrared bands. This is an important enhancement since images from the visible band, long-wave infrared (IR) window band centered at 10.7 microns (µm), and infrared water-vapor band centered at 6.7 µm depict basic visual and thermal features of the Earth's surface, clouds, and the distribution of upper-tropospheric moisture.

The Imager

  • Channel 1, the visible channel, has a wavelength range of 0.52-0.75 µm. Major improvements include improved detector technology, 10-bit imagery (versus 6-bit for GOES 7), improved detector type, and increased sampling frequency. The improved detector technology allows for precise detector-to-detector matching, which eliminates striping in imagery. The increased sampling frequency allows for better cloud detection, while the 10-bit imagery provides 1024 brightness levels versus 64 with 6 bits. With proper image enhancement, these new capabilities improve cloud-edge and cloud-top feature detection, which should lead to improvements in identifying storms and cloud-drift winds; extend the use of visible imagery into low-light situations; help in detecting, and potentially assessing, pollution and haze; and permit highly accurate measurement of cloud heights during daylight hours using both stereo and cloud-shadow techniques.
  • Channel 2, in the wavelength interval 3.78-4.03 µm, is the shortwave infrared window channel referred to as the 3.9-µm channel. Major improvements have been made in spatial resolution and sensitivity, which greatly increase our ability to identify fog at night; locate water clouds over snow during the daytime; delineate between supercooled water clouds and ice clouds during daytime (with long-wave IR); and detect hot areas such as fires and volcanoes. At night this band has the potential for improving sea-surface temperature measurements due to decreased diffraction, as compared to the long-wave IR channels.
  • Channel 3, in the wavelength interval 6.5-7.0 µm, is the water-vapor infrared channel, also termed the 6.7-µm channel. Its quality, compared to earlier GOES imagers, is an order of magnitude better. Time-lapse loops of water-vapor imagery are used to estimate regions of mid- and upper-level moisture advection and drying and to locate meteorological features such as jet streams, tropopause folds, vorticity centers, and cutoff lows.
  • Channel 4, with a wavelength range of 10.2-11.2 µm, is the long-wave infrared window. This channel has a twofold improvement in spatial resolution, which facilitates detecting cloud-edge and cloud-top features. This improves the accuracy of detecting cloud-drift winds, identifying severe storms, and locating storms with heavy rainfall. In combination with the Channel 5 (11.5-12.5 µm) band, better surface skin temperature mapping and low-level moisture identification are possible. With Channel 5 and the shortwave infrared channel, higher accuracy in sea-surface temperatures is expected.
  • Channel 5 (11.5-12.5 µm) is a moisture-contaminated or "dirty" window. This channel covers a larger spectral width than the previous GOES. Its signal-to-noise improvement should lead to the development of much more accurate measurement of low-level moisture, surface temperature, and stability products, which are valuable for all types of convective forecasting and in situations where diabatic heating is important. In stable situations, this information is used in recognizing areas with a potential for radiation-fog development.

The Sounder

  • The new sounder has 18 infrared bands plus a low- resolution visible band. The earlier sounder had 12 infrared bands plus a visible band.
  • It is designed to provide data from which atmospheric temperature and moisture profiles; surface and cloud-top temperatures; and ozone distribution can be deduced via mathematical analyses.
  • It operates independently of and simultaneously with the imager, and uses a similar flexible scan system.
  • Its multi-element detector- array assemblies simultaneously sample four separate fields of view or atmospheric columns. A rotating filter wheel, which brings spectral filters into the optical path of the detector, provides the infrared channel definition.
  • It provides new channels and atmospheric-profiling capabilities not previously available on a geostationary satellite.
In summary, the full-time availability of the GOES sounder enables operational use of sounding products and multichannel upwelling radiances for the first time. This has the potential for contributing significantly to mesoscale analysis, model-data assimilation, and forecasting over the CONUS; monitoring thermal winds over oceans; and supplementing the Automated Surface Observing System (ASOS) with upper-level cloud information. The independent sounder now allows complete hourly coverage of the CONUS. The sounder can depict boundary-layer properties that may be influencing the development of convective activity. The short-wave bands will provide improved surface skin temperature and lower-layer moisture determinations. The net flux divergence and the inferred cooling rate will be determined on the mesoscale; these can be used to describe the radiative processes over terrain features surrounding atmospheric instabilities. The availability of simultaneous sounding and imaging data will provide products which integrate the information on cloud, Earth-surface, and atmospheric conditions.

Examples from GOES 8 and 9

Much to the delight of the meteorological community, the high-speed, high-resolution capabilities of GOES 8 and 9 imagers began providing insights to weather phenomena almost immediately. See, for example, the super-rapid-scan image loop of a severe thunderstorm near Tulsa, Oklahoma, on July 20, 1994 (link no longer available).

Examples of real-time data are available on the Web: Look at servers maintained by the University of Wisconsin-Madison's Space Science and Engineering Center and by Colorado State University as well as those maintained by many other Unidata participants.

GOES in Unidata Data Streams

The Unidata community's access to current GOES data has been limited. Because of bandwidth constraints in the old satellite data-distribution system, the Unidata/Wisconsin data stream, which provides the Unidata community with satellite images, contains only a small selection of the GOES 8 and 9 images, and none of the sounding data.

With the sunset of Unidata's old data-distribution system (see "Satellite Broadcast...") and with the greater bandwidth provided by Unidata's Internet Data Distribution (IDD) system, the community faces the happy prospect of soon being able to access a wider range of satellite data (the exact amount being now constrained by the cost of preparing the images for distribution). The question now facing the community is: What satellite data should be included in the Unidata/Wisconsin data stream?

To help answer this, the Unidata Users Committee designed a Web-based questionnaire and in November asked the community to respond to it. The decision on what further GOES data to disseminate will need to be made fairly soon. The Users Committee therefore invites you to respond to the questionnaire by mid-April.

See the Unidata/Wisconsin data stream homepage for samples of the regions covered by these images (website no longer available).

Current Unidata/Wisconsin Stream

Unidata currently distributes GOES-8 and -9 image data only; no sounding data is distributed. Water vapor, IR, and visible images and a floater image are distributed hourly. An Antarctic composite is distributed every three hours.

The Unidata/Wisconsin stream also contains hourly manually digitized radar images and some surface and upper-air data in McIDAS MD-file format. There is also the special floater sector, which varies with the meteor-ological conditions across the country. Users may request special sectors or products by sending e-mail to floater-request@unidata.ucar.edu.

Possible GOES Data

Follow these links to tables displaying the image and sounding data available from the GOES satellites. As of January, 33 people had responded to the Users Committee's survey. Based on these responses, the committee is considering adding the following to the Unidata/Wisconsin data stream:

  • Images: 30-minute images from channels 1, 3, and 4; and hourly images from channels 2 and 5
  • Derived and sounder products:
    • Hourly: total precipitable water, lower precipitable water, surface skin temperature, lifted index, cloud-top pressure
    • Three-hourly: All derived sounding profiles in a single McIDAS MD file
Users could also have FTP access to additional files at SSEC.

There are other options available for real-time access to GOES data. For under $1,000, users interested in a relatively inexpensive, low-resolution products may purchase off-the-shelf, direct-readout, WEFAX stations which run on older PCs. Further information about WEFAX may be found on the NESDIS NOAASIS homepage or from Florida EXPLORES!

Users can also purchase a GOES groundstation. A fully capable direct readout groundstation for GOES processing at full 10-bit resolution may run from $20,000 to more than $100,000. Many institutions that operate such groundstations place their imagery on information servers and homepages (e.g., NOAA, NASA, and university sites).

For Further Info on GOES 8 and 9

The NOAA Web server contains a good summary of the overall mission of the GOES I/M satellites.

Also, personnel at NESDIS Regional and Mesoscale Meteorology Branch of NOAA and the Cooperative Institute for Research in the Atmosphere (CIRA) at Colorado State University have developed a GOES 8 tutorial.

And the Cooperative Institute for Meteorological Satellite Studies (CIMSS) at the University of Wisconsin-Madison has prepared a tutorial on the GOES 8 sounder.

January 1997 Sunset for McIDAS-OS2 VGA Mode, OS/2 2.x

by Don Murray, User Support Programmer at the Unidata Program Center

Next January, Unidata will sunset support for the VGA mode of McIDAS-OS2. We will continue to support the Presentation Manager (PM) mode, which has many advantages over VGA, including 48 gray shades for imagery (instead of 16); eight additional separate graphics colors; separate text and image windows; and briefing frames. At the same time, Unidata will sunset support for OS/2 version 2.1 and will only support OS/2 Warp or later versions.

Running in PM mode requires a more powerful machine than does VGA mode. The minimum machine requirements for the former are:

  • 486/66-MHz or Pentium-class machine
  • SVGA graphics accelerator
  • Local bus graphics (preferably PCI)
  • 16 MB RAM
  • OS/2 2.1 or OS/2 Warp
  • 200+ MB hard drive
If your equipment does not meet these requirements, you need to plan on upgrading your systems. These are the minimum requirements; we recommend a Pentium-class machine with a PCI bus and PCI graphics accelerator for smooth looping. Sites should also get 32 MB RAM or more if they can afford it. A minimum of 200 MB of disk space would be sufficient for a non-ingesting McIDAS workstation, but over a gigabyte is recommended for a machine that will be ingesting data via the IDD. We will be providing software for ingesting other data streams (DD+, IDS, NIDS) in the next couple of months, which will require the additional disk space. Finally, all sites must be running OS/2 Warp in January 1997. For ingesting machines, TCP/IP 2.0 or Warp Connect is required to use the latest version of McIDAS-OS2.

Sunsetting means that any new development after the sunset date is not guaranteed to work with the sunsetted system. However, the programs and menus available at the sunset date for VGA mode and OS/2 2.x will still be usable to display the data available on the Unidata/Wisconsin data stream at the time of the sunset. New products added after that date may require additional software that may not be compatible with VGA mode or OS/2 2.x.

The sunset of VGA mode is required because as we make new features available, it is increasingly difficult to maintain compatibility between VGA and PM modes while maintaining compatibility with McIDAS-X. A good example is the recent release of topographic imagery. It required a considerable amount of extra coding and testing to ensure that the additions worked in VGA mode. In the end, however, the results are far superior in PM due to the extra image levels.

During 1996, we will be working on a graphical user interface (GUI) for McIDAS-OS2 to augment and eventually replace the F-key menu system. For this to work, McIDAS must run in a windowed mode on the OS/2 desktop instead of a full screen mode like VGA.

We understand that this will create problems for sites that have several older machines. However, in order to provide a useful product, we must advance with the technology. If you have several machines that need upgrading, you might consider replacing them one by one as your budgets permit. Try to take advantage of opportunities for matching equipment grants through NSF or other agencies that may help you perform the necessary system upgrades. To extend the useful life of your system, you should consider purchasing machines beyond the minimums listed above. You also need to plan for more upgrades in the future, because the technology is continually changing. One suggestion is that sites budget some money each year for incremental software and hardware upgrades of their machines. (See "Advancement vs. Stability").

As you move to PM mode of McIDAS-OS2, you will find that the higher resolution display makes McIDAS more useful for image and general meteorological analysis. As new imagery data sets are added to the Unidata/Wisconsin data stream, this will become increasingly important. A comparison of the difference between imagery displayed in VGA mode and PM mode is available on the Web (link no longer available).

Additionally, since PM mode requires a more powerful machine, you won't have to wait as long for commands to be processed. These faster machines will be able to ingest and display other data sets like NIDS and lightning data that are not currently available to OS/2-only sites. The end result of moving to a machine running McIDAS-OS2 in PM mode is a better meteorological display and analysis tool.

If you have any questions about upgrading your systems, please contact Unidata support (support@unidata.ucar.edu).

Sponsored Participation Policy

The National Science Foundation funding for and mission of the Unidata Program are targeted toward the US university community. Institutions from that community (specifically, academic departments that offer graduate or undergraduate courses and degrees) constitute the core membership of Unidata. All Unidata products and services are available to core members, and individuals from such institutions hold all of the voting seats on the Unidata Policy Committee. Recognizing that core Unidata members often have synergistic relations with other types of institutions, such as research centers and universities in other countries, this document defines a mechanism by which such organizations potentially can join in the Unidata Program, on a limited basis, as sponsored participants. The key to such participation is having a willing sponsor from within the core membership of Unidata. The policy for sponsored participation is detailed in the following points.

  1. An institution is considered a sponsored participant in Unidata only if a core member, as determined by the Unidata Program Center, has formally expressed the willingness to be a sponsor. Typically this expression takes the form of a letter from the head or chair of the sponsoring department to the Director of the Unidata Program Center at the University Corporation for Atmospheric Research, indicating willingness to hold the responsibilities described in items two and three.

  2. The sponsor supplies data to the sponsored participant, consistent with applicable data usage and other constraints. The Unidata Program Center, as part of its support for the Internet Data Distribution (IDD) system, will assist the sponsor in this role, but sponsored participants' data reception will not be monitored, repaired, tuned, or otherwise supported directly by Program Center staff.

  3. The sponsor helps the sponsored participant to use Unidata systems and software, consistent with applicable licenses and other constraints. The Unidata Program Center, as part of its support for all core members, will assist the sponsor in this role, but sponsored participants can expect no direct assistance from Program Center staff.

  4. Sponsored participants using Unidata software and data streams must do so within the constraints imposed by the authors/owners of the software and by the providers of the data. For example, data gained via Unidata are to be used only for research and education. Similarly, international data exchanges should be undertaken only in accordance with applicable laws, policies and practices, such as those adopted by the World Meteorological Organization (WMO) in Resolution 40 October 1995 on the Global Exchange of Data.

  5. As a general rule, the Unidata Program Center will expend no resources to help sponsored participants gain access to data or software. An exception is that software developed entirely at the Center (i.e., no other parties have ownership) will be made available to sponsored participants at no cost. sponsored participants must acquire this software via the Internet and, as discussed earlier, must use it without direct assistance from the Center.

  6. On a space-available basis, sponsored participants may attend Unidata training workshops at no cost.

  7. Sponsored participants, as well as their sponsors, are expected to utilize Unidata's on-line support services and employ adequate resources and expertise such that sponsored participation does not have an unreasonable impact on the overall Unidata Program, especially on data flows and user-support efforts.
This policy implies that sponsored participants must arrange directly with the providers to use data streams or software packages outside the limits imposed on Unidata by those providers. At present, for example, a sponsored participant would have to gain agreement with Purdue to use WXP, with the University of Wisconsin to use McIDAS, with Cosmic or the National Weather Service to use GEMPAK, with the WSI Corporation to receive NIDS data, and with Global Atmospherics to receive lightning data.

If you have questions concerning sponsored paricipation, contact Linda Miller(lmiller@unidata.ucar.edu).

Advancement vs. Stability - The Case for Current Hardware and Software

by Dave Fulker, Unidata Program Director The universities that Unidata serves function in a technological environment so dynamic that we must continually weigh the merits of change against those of stability. Nowhere is this challenge greater than in the arena of "supported" platforms. Each time Unidata stops supporting a given type of hardware or operating system, at least one college or university struggles with the resultant need to upgrade or replace equipment or software. However, failure to move ahead is a recipe for disaster, eventually yielding obsolescence on a community-wide scale.

Thus, with the assistance of the Users and Policy Committees, we try to strike a suitable balance between utilizing leading-edge technology and maintaining sufficient stability for users to gain full value from their hardware and software investments. When the balance favors cessation of support for a platform or technology, we give what we hope is adequate notice to permit preparation for the change. The sunset date for VGA mode in McIDAS-OS2 is typical in providing nearly a year of lead time in which to plan for equipment upgrades.

To make this balancing act work for everyone, we need your assistance. If our user community remains up-to-date in respect to technology, our balancing act is less difficult and we can focus on enhancing our tools with the most effective methods available. Thus I encourage planning and budgeting for regular hardware and software upgrades, based on the view that these are now critical to the health of any academic program that entails meteorological studies. If you think the Unidata Program Center could help you to make a case (to a department head or other administrative official) for the required commitments, please e-mail me.

Arrivals and Departures

Steve Chiswell (better known as "Chiz") joined the Unidata staff last October, following post-doctoral work at the University of Hawaii. Steve works primarily on GEMPAK, and is currently concentrating on the release of GEMPAK 5.2.1. When not working, Steve says his interests include "cool storms" and "assorted fermented beverages."

Another recent addition to our staff is student assistant Jennifer Philion. Jen is a news/editorial major in the University of Colorado's journalism school. She is responsible for the addition of many years of Unidata Newsletter back issues appearing on our Web server. We feel a little safer in the office because Jen is also a parttime NCAR security guard on the weekends. When all of this isn't keeping her busy, you'll probably find her snowboarding in Colorado's high country.

On the outbound train we find administrative assistant Cindy McCombs. Cindy came on board last winter but has been on maternity leave since the birth of her son in January. Cindy recently decided not to return to Unidata but to stay at home and care for her baby.

Satellite Broadcast Served Community Well--Service Turned Off on January 9

by Don Murray, User Support Programmer at the Unidata Program Center On January 9, 1996, the satellite broadcast of the Unidata/Wisconsin data stream was discontinued. This marked the end of an era in the Unidata community and completes the transition to the Internet Data Distribution (IDD) system. The satellite distribution of this data stream was the first method that provided Unidata sites with real-time satellite imagery and conventional data sets for use with PC-McIDAS (and later WXP and GEMPAK).

As the data needs of the Unidata community increased, the limited bandwidth (9600 bps) of the satellite-based broadcast had restricted the addition of new types of imagery and products (see the GOES article). Now that most Unidata sites are connected to the Internet, the virtually unlimited bandwidth of the IDD has superseded the satellite-based broadcast. While most UNIX sites were using the LDM software to ingest the IDD version of the Unidata/Wisconsin data stream, several OS/2 sites were still relying on the KU broadcast. Now, however,OS/2 sites can directly ingest the data stream from the IDD using the McLDM program developed at the UPC and distributed with McIDAS-OS2. In addition to the Unidata/Wisconsin data stream, it will also ingest other IDD streams (IDS, PPS, HRS) when used in conjunction with the OS/2 version of McIDAS-XCD. That package will be released in the second quarter of 1996. Information on receiving and ingesting the Unidata/Wisconsin data stream can be found on the McIDAS homepage.

What's New on the Unidata Web Server

Compiled by Jennifer Philion, Student Assistant at the Unidata Program Center

We are constantly modifying the Unidata Web server. If you have not already found our recent changes, here are some of them:

On the homepage:

  • We added a questionnaire for people involved in geosciences other than atmospheric science, to determine if and how Unidata can benefit these groups. (This was recently removed from the server; thanks to those who responded.)
  • We added a "Search this server" link. Web indexing is a task that is still in its infancy, but you may find this feature useful on occasion.
  • Under "Other News," we added the Sponsored Participation Policy, as adopted by the Unidata Policy Committee in September 1995.
  • The "Around Boulder and Colorado" page has been expanded and updated.
  • Access to the Unidata Gopher has been removed and the Gopher server has been shut down.

In the "Data" section:

Elsewhere:

  • Under GEMPAK "Package Information," GEMPAK 5.2.1 information has been added.
  • In the Unidata Newsletter section, we have added back issues from 1987-1991 and 1993. We have also created a new index that lists newsletter articles by title.
A non-Unidata activity that is of possible interest to the Unidata community is the Information Infrastructure Technology and Applications (IITA) program at UCAR.The program is closely connected to Unidata. IITA funding supports a workstation running the Local Data Manager (LDM) for use within UCAR and NCAR, and to serve as a data relay for our Internet Data Distribution (IDD) system. Their web site provides an overview of the program.

We are constantly updating pages throughout our Web server, in hope that the information they contain is useful enough that you check back regularly. If there is additional information you would like us to provide, please e-mail us.

We also hope you will inform us when you establish or change to a new server, by sending an e-mail to url-report@unidata.ucar.edu. With your help, we can keep our links to information servers at Unidata sites up to date.

A Data Page Disclaimer

Many of you have set up Web sites to provide current weather information. While this is a useful and popular service, it does have potential legal ramifications. There is a possibility (however remote) that someone will use the information for purposes for which it is not suited or reliable and that use may lead to losses or damages for which they could try to hold you or your institution responsible. In order to avert such situations, we enlisted UCAR's legal department to pen a disclaimer that you can add to your data pages to provide some degree of protection against spurious legal actions. We suggest that you create a disclaimer page containing the text below and provide a link to that page from each data page of your site.

DATA DISCLAIMER

USE AT YOUR OWN RISK

The authorized use of this data is limited to academic and educational purposes only, and NOT for operational or commercial purposes. THIS DATA IS PROVIDED "AS IS" AND IN NO EVENT SHALL THE PROVIDERS BE LIABLE FOR ANY DAMAGES, INCLUDING, WITHOUT LIMITATION, DAMAGES RESULTING FROM LOST DATA OR LOST PROFITS OR REVENUE, THE COSTS OF RECOVERING SUCH DATA, THE COSTS OF SUBSTITUTE DATA, CLAIMS BY THIRD PARTIES OR FOR OTHER SIMILAR COSTS, OR ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, ARISING OUT OF THE USE OF THE DATA. The accuracy or reliability of the data is not guaranteed or warranted in any way and the Providers disclaim liability of any kind whatsoever, including, without limitation, liability for quality, performance, merchantability and fitness for a particular purpose arising out of the use, or inability to use the data.

A Modest Request

In these times of budget cuts, all of us receiving government funds need to be able to justify our existence. One way Unidata and government organizations such as the NWS can do this is to point to the many Web sites using Unidata systems and NWS data. In order that Unidata's and the NWS's contribution to the common good might be more easily recognized, we would like to request that you include (if you do not already do so) an acknowledgment line on at least your main data page. A suggested acknowledgment (with HTML tags) follows:

"These pages made possible by systems from the Unidata Program Center and data from the National Weather Service."

The HTML for this acknowledgement looks like this:

"These pages made possible by systems from the <A HREF="http://www.unidata.ucar.edu">Unidata Program Center</A> and data from the <A HREF="http://www.noaa.gov/nws/nws_intro.html">National Weather Service</A>."

GEMPAK News

by Steve Chiswell, User Support Programmer at the Unidata Program Center

Unidata released its version of GEMPAK 5.2.1 in January. This is the first official Unidata release to support imagery from the new generation of GOES satellites and to include the ability to read WSI's NIDS and NOWRAD data in their native file formats. Among other additions is the ability to read grid files in netCDF format.

Also included with this release are the N-AWIPS graphical user interfaces that are being developed by the National Centers for Environmental Prediction (NCEP) and the Cooperative Program for Operational Meteorology, Education and Training (COMET). In addition to the Unidata community, the COMET training classroom and the National Weather Service's SOO/SAC program are using GEMPAK 5.2.1, allowing increased interaction among these groups.

A complete tutorial for the spring 1996 GEMPAK workshop is available on our Web server.

Concurrent with the release of GEMPAK 5.2.1, COMET has announced the availability of data in case-study format designed for use in the GEMPAK/N-AWIPS environment. The first three cases in the series are now available:

  • Case 1: 1993 "Storm of the Century."
  • Case 2: A Midwest snowfall event from December 1995, with more subtle forcing than many classical case studies address.
  • Case 3: Details Hurricane Opal of 1995.
Included with each module are references to published and prepared texts regarding the events surrounding the case. Exercises are also available where applicable. Unidata sites that want to order any of the case studies should contact csl@comet.ucar.edu. Future announcements regarding case-study availability will appear on the Unidata GEMBUD e-mail list.

RAMSDIS: McIDAS-OS2 and More

by Tom Yoksas, User Support Programmer at the Unidata Program Center

The NOAA/NESDIS Regional and Mesoscale Meteorology Branch (RAMMB) and the NOAA Cooperative Institute for Research in the Atmosphere (CIRA), at Colorado State University, have developed a menu-driven system for Pentium PCs that enhances the capabilities of McIDAS-OS2. The McIDAS extensions, called RAMSDIS, are presently installed at over fifty National Weather Service forecast offices and many additional NOAA research laboratories.

RAMSDIS was designed to take advantage of a special data stream produced for the forecast offices by NESDIS that contains high- resolution data from the GOES 8 and GOES 9 satellites (see article). In the forecast offices, the RAMSDIS software is running on Pentium-class machines (90 MHz or faster, with 32 MB of RAM and 1 GB disks) with specific graphics cards (ATI Mach 32 or 64). The use of these cards allows the display of 640x480-pixel imagery in 256 shades of gray or graphic colors.

RAMMB and CIRA have licensed the Unidata Program to distribute RAMSDIS to Unidata participants. Unidata support expects to bundle RAMSDIS with its McIDAS-OS2 distribution later this year. When they are available to us, Unidata will bundle UNIX versions of RAMSDIS routines with McIDAS-X. While RAMSDIS can be used to view data from the Unidata/Wisconsin data stream, some of the software routines will not work without the NESDIS data stream or without the specified video cards.

A summary of the capabilities and features of RAMSDIS is contained at the RAMSDIS homepage.

Please send comments to info@unidata.ucar.edu