U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Vol. 7, No. 4 ● June 1997 E ARTH S YSTEM M ONITOR A guide to NOAA's data and information services INSIDE 3 News briefs 6 The NSIDC EASE-Grid 8 World Wide Web and Java-based Remote Systems Monitoring 11 The ESDIM Program 13 NOAA Coastal Ocean Data Workshop 15 Data products and services D E P A R T M E N T O F C O M M E R C E ★ ★ U N I T E D S T A T E S O F A M E R I C A NCDC’s Environmental Satellite Database – continued on page 2 Robert Boreman Satellite Data Services Group National Climatic Data Center NOAA/NESDIS The National Climatic Data Center (NCDC) is the world’s larg- est active archive of weather and environmental satellite data, and the National Archives and Records Administration has designated NCDC as the U.S. Department of Commerce’s only Agency Records Center. The weather data are ob- tained from the National Weather Service (NWS), military services, the U.S. Coast Guard, the Federal Avia- tion Administration, and voluntary cooperative observers. Satellite data are obtained from the NOAA Na- tional Environmental, Satellite, Data, and Information Service (NES- DIS), from the Department of De- fense, and from the National Aeronautical and Space Administra- tion (NASA). The Center has more than 150 years of data on hand and main- tains 544 different data sets. NCDC archives contain 99 percent of all NOAA data holdings, including observations from NWS surface stations, upper air stations, NEXRAD radar sites, cooperative stations, ship and buoy reports, DOD installations, and environ- mental satellites. The archive contains 460 tera- bytes of data and is growing at the rate of about 10 terabytes each month. There are 320 million paper records, 1.2 million microfiche records, 510,000 tape cartridges and magnetic tapes, and approximately 175,000 hardcopy satellite images (Figure 1) stored at the Center. NCDC responds to nearly 175,000 off-line, and over 1 million online customer requests for climatic data and information each year. Monthly and annual publications are prepared for the more frequently requested data, and nearly 2 million copies are provided to subscrib- ers and intermittent users annually. NCDC’s environmental satellite database accounts for almost 230 terabytes, or 50 percent of the total current archive. This includes 40 terabytes of polar orbiter satellite data, and 190 terabytes of geostationary satellite data. The physical location of these data are: Asheville, North Carolina; Suitland, Maryland; and the Space Science and Engineering Center at the Uni- versity of Wisconsin. Most of the servicing func- tions are provided by NCDC’s Satellite Data Services Group at Asheville, North Carolina. The environmental satellite data base, an element of the overall NESDIS database, is a The National Climatic Data Center offers users unique environmental data ▲ Figure 1. NOAA satellite imagery depicting a weather system which initially formed in the Atlantic Ocean and moved to the In- dian Ocean, affecting Cape Town, South Africa along the way. Satellite Data Services Group National Climatic Data Center 151 Patton Avenue Asheville, NC 28801-5001 E-mail: [email protected]
Transcript
U.S. DEPARTMENTOF COMMERCE
National Oceanicand AtmosphericAdministration
Vol. 7, No. 4 ● June 1997
EARTH SYSTEM MONITOR
A guide toNOAA's data and
informationservices
INSIDE
3News briefs
6The NSIDCEASE-Grid
8World Wide Web and
Java-based RemoteSystems
Monitoring
11The ESDIM Program
13NOAA Coastal Ocean
Data Workshop
15Data productsand services
DE
PA
RTMENT OF COMMERC
E
★ ★
UN
ITEDSTATES OF AMER
ICANCDC’s Environmental Satellite Database
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Robert BoremanSatellite Data Services GroupNational Climatic Data CenterNOAA/NESDIS
The National Climatic DataCenter (NCDC) is the world’s larg-est active archive of weather andenvironmental satellite data, andthe National Archives and RecordsAdministration has designatedNCDC as the U.S. Department ofCommerce’s only Agency RecordsCenter. The weather data are ob-tained from the National WeatherService (NWS), military services, theU.S. Coast Guard, the Federal Avia-tion Administration, and voluntarycooperative observers. Satellite dataare obtained from the NOAA Na-tional Environmental, Satellite,Data, and Information Service (NES-DIS), from the Department of De-fense, and from the NationalAeronautical and Space Administra-tion (NASA).
The Center has more than 150years of data on hand and main-tains 544 different data sets. NCDCarchives contain 99 percent of allNOAA data holdings, includingobservations from NWS surfacestations, upper air stations,NEXRAD radar sites, cooperativestations, ship and buoy reports,DOD installations, and environ-mental satellites. The archive contains 460 tera-bytes of data and is growing at the rate of about10 terabytes each month. There are 320 millionpaper records, 1.2 million microfiche records,510,000 tape cartridges and magnetic tapes, andapproximately 175,000 hardcopy satellite images(Figure 1) stored at the Center.
NCDC responds to nearly 175,000 off-line,and over 1 million online customer requests forclimatic data and information each year.Monthly and annual publications are prepared
for the more frequently requested data, andnearly 2 million copies are provided to subscrib-ers and intermittent users annually.
NCDC’s environmental satellite databaseaccounts for almost 230 terabytes, or 50 percentof the total current archive. This includes 40terabytes of polar orbiter satellite data, and 190terabytes of geostationary satellite data. Thephysical location of these data are: Asheville,North Carolina; Suitland, Maryland; and theSpace Science and Engineering Center at the Uni-versity of Wisconsin. Most of the servicing func-tions are provided by NCDC’s Satellite DataServices Group at Asheville, North Carolina.
The environmental satellite data base, anelement of the overall NESDIS database, is a
The National Climatic Data Center offers users unique environmental data
▲ Figure 1. NOAA satellite imagery depicting a weather systemwhich initially formed in the Atlantic Ocean and moved to the In-dian Ocean, affecting Cape Town, South Africa along the way.
Satellite Data Services GroupNational Climatic Data Center151 Patton AvenueAsheville, NC 28801-5001E-mail: [email protected]
2 June 1997EARTH SYSTEM MONITOR
EARTH SYSTEM MONITOR
The Earth System Monitor (ISSN 1068-2678) is published quarterly by the NOAAEnvironmental Information Services office.Questions, comments, or suggestions forarticles, as well as requests for subscrip-tions and changes of address, should bedirected to the Editor, Sheri A. Phillips.
The mailing address for the EarthSystem Monitor is:
National Oceanographic Data CenterNOAA/NESDIS E/OC1SSMC3, 4th Floor1315 East-West HighwaySilver Spring, MD 20910-3282
DISCLAIMERMention in the Earth System Monitor ofcommercial companies or commercialproducts does not constitute an endorse-ment or recommendation by the NationalOceanic and Atmospheric Administrationor the U.S. Department of Commerce.Use for publicity or advertising purposes ofinformation published in the Earth SystemMonitor concerning proprietary productsor the tests of such products is notauthorized.
U.S. DEPARTMENT OF COMMERCEWilliam M. Daley, Secretary
National Oceanic andAtmospheric Administration
D. James Baker,Under Secretary and Administrator
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unique source of data and information.It contains film imagery and digital datacollected by a number of environmentalsatellites from 1960 to the present.These satellites include the NationalOceanic and Atmospheric Administra-tion operational environmental satel-lites, various NASA research satellites,and the Department of Defense Meteo-rological Satellite Program (DMSP). Dataare available from the TIROS Series be-ginning with TIROS-1 (June 1960)through TIROS-10 (April 1966), ESSA,ITOS, GEOS-3, SEASAT, NIMBUS-7,DMSP F-8 through F-13, NOAA-1through NOAA-14, and the geostation-ary satellites ATS-1 launched in 1966through GOES-9 launched in May 1995.
In the future, data from the Cana-dian satellite, RADARSAT, will be madeavailable on a limited basis to NCDC.While many of the collected data aremeteorological (Figure 2), the data havebeen of considerable interest to agrono-mists, oceanographers, hydrologists,and geologists as well.
There are two basic types of envi-ronmental satellites: polar orbiting andgeostationary. The instruments aboardthe Polar Orbiting Environmental Satel-lites (POES) and the Geostationary Or-
biting Environmental Satellites (GOES)are presently collecting data which areavailable in image form and digital for-mat.
The polar orbiting satellites operatein relatively low orbits, ranging from700 to 1,700 km above the earth, andcircle the earth 12 to 14 times per day(orbital periods from 99 to 115 min-utes). The orbits are timed to allow com-plete global coverage twice per day(normally a daytime and a nighttimeview of the earth) in swaths of about2,000 km in width. Because of the polarorbiting nature of the POES series satel-lites, these satellites are able to collectglobal data on a daily basis for a varietyof land, ocean, and atmospheric appli-cations.
Data from the POES series supportsa broad range of environmental moni-toring applications including weatheranalysis and forecasting, climate re-search and prediction, global sea surfacetemperature measurements, atmo-spheric soundings of temperature andhumidity, ocean dynamics research,volcanic eruption monitoring, forest firedetection, global vegetation analysis,and many other applications.
High resolution (1 km) data are
Satellite imagery, from page 1
▲ Figure 2. This satellite image depicts a stationary front stretching from Texas to WestVirginia that spawned several tornados, one of which destroyed sections of Arkadelphia,Arkansas (arrow points to Arkadelphia).
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3June 1997 EARTH SYSTEM MONITOR
News briefssium in a final day plenary session (offer-ing conclusions to the ocean science com-munity, policy makers and to ocean datamanagers). Meeting attendees will includescientists working in all aspects of oceanclimate studies, data managers responsiblefor all types of ocean information, andpersons involved in ocean monitoring andprediction.
Some of the topics anticipated to beaddressed by the presenters include :• the role of the ocean in climate change;• statistics and data for ocean scientists;• implications of ocean color research;• data precision and quality;• how to preserve data for future use;• GOOS - what are the needs for globalprograms?• data archaeology;• problems associated with integrateddata sets;• case studies from both large and smallscale projects;• the importance of metadata to scienceand data management;• advances in IT (Information Technol-ogy);• requirements for modelling;• lessons that can be learned from pastscience programs;• data management decision supporttools; and• and visualization and management ofocean data, as well as telecommunicationsand data exchange systems. In addition,the organizers would be happy to receivecontributions on related material.
The exhibition of services, hardwareand software and related products willform an integral part of the symposium,with hands-on demonstrations of prod-ucts. Persons wishing to demonstrate ITpackages are invited to submit a shortdescription of their proposed demonstra-tion. Abstracts were due May 30, 1997;notice of acceptance is due June 27, 1997.Full papers and early registration are dueAugust 1, 1997.
Send information requests, posters,and abstracts to:OD Conference DeskIrish Marine Data Centre80 Harcourt StreetDublin 2IrelandPhone: +353-1-475-7100Fax: +353-1-475-7104E-mail: [email protected]
NCDC’s 1997 State ClimatologistExchange Program
Scientists from six states will partici-pate in the National Climatic DataCenter’s (NCDC) State Climatologist Ex-change Program during 1997. These par-ticipants include:• Dr. Steve Qi Hu, a Missouri State Clima-tologist, will investigate pre-1982 soil tem-perature data for Missouri and its sur-rounding states and develop an inventorydesigned to make the data more usable;• Dr. Patricia A. Bresnahan, Assistant Con-necticut State climatologist, will developsampling and format conversion algo-rithms for various NCDC datasets. Thealgorithms will allow the datasets to becompatible with the scale surface trans-port models at local and landscape levels.• Mr. Dwight D. Pollard, Alaska StateClimatologist, will review the processingand quality control of hourly precipitationdata at NCDC and develop similar proce-dures for Alaska stations.• Mr. John Purvis, a South Carolina Assis-tant State Climatologist, plans to accom-plish a NEXRAD precipitation storm accu-mulation study for the Santee Cooperlakes in South Carolina. In addition, Mr.Milton Brown, South Carolina AssistantState Climatologist, plans to work withNCDC staff to develop a better under-standing of the interconnections betweenthe ocean and atmosphere which mayaffect major events in the southeast, suchas drought and heavy precipitation. Acorrelation will be developed between ElNiño and southeast droughts.• Dr. Donald T. Jensen, Utah State Clima-tologist, will gather and digitize additionalstation data from NCDC archives. He alsoplans to share techniques and technolo-gies developed from Utah’s spatial andtemporal distribution methods.• Dr. John F. Griffiths, Utah State Clima-tologist, will continue research on the coldoutbreak which occurred east of theRockies in the year 1843. The researchshould yield information on the basic syn-optic patterns that assailed the region byidentifying the onset and speed of thecold fronts.
NGDC scientists attend Rim of theGulf conference
Scientists from the National Geo-physical Data Center (NGDC) recentlyattended the “Rim of the Gulf: RestoringEstuaries and Resources Conference”, heldin Portland, Maine. The conference was
dedicated to improving scientific under-standing and management of the Gulf ofMaine and was cosponsored by NOAA.Dr. Elvidge and Mr. Dietz of NGDC areanalyzing land cover change along thecentral coast of Maine using Landsat dataas part of the NOAA/NESDIS GovernmentApplications Task Force project. In addi-tion, they are investigating the use of hightide/low tide aerial photography for map-ping and characterizing the intertidal zonefor portions of the central coast of Maine.For more information, please see theNGDC home page at http://www.ngdc.noaa.gov.
Ocean data symposium to be heldin Ireland
A Symposium on Ocean Data forScientists will be held on October 15-18,1997 at Dublin Castle, Dublin, Ireland.The Symposium objective is to assess thedata management requirements of oceanscientists and to investigate the applica-tion of technological advances in order toincrease the efficiency and effectiveness ofpresent data management methods. TheSymposium is being sponsored by theNational Oceanic and Atmospheric Ad-ministration, the IntergovernmentalOceanographic Commission, EU MarineScience and Technology, and the MarineInstitute, Ireland. Themes of the Sympo-sium are:1) the data and metadata requirements ofscientists in order to support ocean re-search;2) the benefits modern technology offersto scientists and the facilities available forthe analysis and exchange of ocean data;3) developing the use of advanced tech-nology for data collection, analysis andexchange; also the implication of thesedevelopments on ocean studies world-wide;4) advances in the development of infor-mation and data management tools forpolicy and decision makers.
The Symposium format includes pa-per presentation sessions, workshops,panel discussions (with rapporteurs), dem-onstrations, poster displays, and exhibitionby service and technology suppliers. Areception hosted by the Minister for theMarine will be held on Oct 15, and therewill be a review of the work of the sympo-
4 June 1997EARTH SYSTEM MONITOR
continuously transmitted from the sat-ellites and can be collected in real-timemode only when the satellites arewithin range of a receiving center.However, recorders on board the satel-lites constantly store reduced resolution(4 km) data, which are then transmit-ted to the receiving stations on laterorbits. NCDC archives both the GlobalArea Coverage (4 km), and the LocalArea Coverage (1 km.) Only a limitedamount of this 1 km resolution datacan be stored on command and down-loaded when the satellites are withinrange.
Each of the two current polar satel-lites, NOAA-12 and NOAA-14, makesnearly polar orbits roughly 14 times aday. The satellite system includes theAVHRR (Advanced Very High Resolu-tion Radiometer) and the TOVS (TIROSOperational Vertical Sounder). TheAVHRR instrument is equipped withfive spectral channels with a near infra-red channel to help monitor globalvegetation, and higher spatial resolu-tion (i.e., 1.1 km at nadir) throughoutthe infrared channels. Complete detailsare provided in a document entitledPolar Orbiter Data User’s Guide, which isavailable from the NCDC.
With the closing of the MarshallSpace Flight Center Distributed Active
Archive Center,NCDC has takenover the respon-sibilities for dis-tributing datafrom the DMSPsatellites to theEarth ObservingSatellite Dataand InformationSystem (EOSDIS)scientists. NCDChas been collect-ing data fromthis polar orbit-ing satellite se-ries for theirown users since1987.
DMSP satel-lite instrumenta-tion includes theSpecial SensorMicrowave/Im-ager (SSM/I), aseven channel,
four frequency, linearly polarized, pas-sive microwave radiometric systemwhich measures atmospheric, ocean,and terrain microwave brightness tem-peratures. These data are available fromDecember 12, 1989 to June 6, 1996 inlevel 1B format, or as EnvironmentalData Records (EDR), Temperature DataRecords (TDR), and Sensor Data Records(SDR) from June 1987 to the present.
Data from the Special Sensor Mi-crowave/Temperature Sounder (SSM/T),a seven channel microwave sounderdesigned to pro-vide global, syn-optic scalesoundings oftemperaturethroughout thetroposphere andlower strato-sphere is avail-able from thebeginning ofAugust 1987 tothe present. Datafrom the SpecialSensor Micro-wave/Water Va-por Profiler(SSM/T2), a fivechannel, totalpower, micro-wave radiometer
with three channel situated symmetri-cally about the 183.31 GHz water vaporresonance line and two window chan-nels, is available from the beginning ofJune 1994 to the present.
The GOES satellite system providescontinuous monitoring necessary forintensive data analyses required byoperational meteorologists and hy-drologists. Each of the GOES satellitesscans predetermined areas of the earth,including the continental UnitedStates, at least four times every hour.In times of severe weather (Figure 3)the GOES satellites are capable of oneminute interval imaging over the af-fected area. NOAA maintains a twosatellite configuration, GOES-West andGOES-East, which enables total cover-age from the central Pacific Ocean east-ward to the west African coast.
Currently, GOES-8 and GOES-9 arepositioned at 75° and 135° west longi-tude, respectively, each orbiting theearth geosychronously along the earth’sequatorial plane at a distance of 35,800km from the earth’s surface. A varietyof products are produced in real-timemode and are directly incorporated intothe daily computer model runs. A num-ber of operational and experimentalimage products are also created anddisseminated hourly to various govern-ment users. All of the data and the op-erational derived products are archivedat the NCDC.
The Satellite Data Services Group ofNCDC receives approximately 300 cus-tomer contacts each month from users
▲ Figure 3. GOES full disk image of a 1984 storm that caused thesinking of the British barque Marques, resulting in the deaths of 19crewmen.
Satellite imagery, from page 2
▲ Figure 4. Mount St. Helen eruption as viewed by the GOES-3satellite May 18, 1980.
5June 1997 EARTH SYSTEM MONITOR
of satellite data and products. Often,these requests go beyond simply fillingan order, but require information aboutthe satellite, instrumentation, datasetformat, or just general informationabout usages of the data. Some of themore common uses are: aircraft acci-dent investigation, hurricane and thun-derstorm studies, training for NationalWeather Service forecasters, studies offlooding events, and lake effect snowevaluation.
Volcano eruption images from sat-ellites are another popular item avail-able from NCDC. The eruption ofMontserrat in the West Indies early in1997 initiated GOES image requestsfrom scientists studying that particularevent. The Government InformationService reported the pyroclastic flowsreached the sea, and ash clouds were ashigh as 20,000 feet. Because of the fall-ing ash, traveling conditions on parts ofthe island were very difficult, withsome roads closed; under these condi-tions satellite imagery is an invaluableresearch tool.
The GOES-3 image of the May 1980eruption of Mount St. Helens offers anextraordinary view of the ash cloud asit begins to rise into the atmosphere(Figure 4). An MPEG video loop of thisevent can be found online at http://www.ncdc.noaa.gov/pub/data/images/
olimages.html.Images of hurricanes (Figure 5) and
tropical storms have been used in fea-ture films, short documentaries, televi-sion productions, educational releases,magazines, and on the nightly news.Many of the best images, and someMPEGs, are found on the NCDC homepage (http://www.ncdc.noaa.gov) as well.Timely reports, such as the March 1997tornadoes and flooding information,are also accessible online with accom-panying satel-lite images.
To obtainfurther infor-mation andup-to-datepricing sched-ules on theNOAA satellitedata productsand servicespresented inthis articleplease contact:Satellite DataServices GroupNational Cli-matic DataCenterRoom 120151 PattonAvenue
Asheville, NC 28801-5001Telephone: 704-271-4850Fax: 704-271-4876E-mail: [email protected] visit our web site at: www.ncdc.noaa.gov/psguide/satellite/sathome.html.
The National Climatic Data Centerarchives digital data, as well as non-digital satellite data, including miscella-neous slides, prints, film, and VHStapes of special events too numerous tolist. Please contact the Satellite DataServices Group for availability of spe-cific images. We also recommend con-tacting us to confirm prices, orderingprocedures, and digital formats.
Digital orders Media type: — Round Tapes-1600/6250bpi — 4mm DAT Tapes — 8mm Exabyte Tapes — 3480 IBM Cartridges — CD-ROM Processing fees: — $75.00 per tape mount ($80.00
per GOES dataset) — $11.00 per output unit — $100.00 per CD-ROM output — $11.00 service & handling per
domestic order; $21.00 per foreign order
File Transfer Protocol (FTP) Services —
GOES data in McIDAS area format:$45.00 per scene (all channels)
▲ Figure 5. GOES-8 color-enhanced image of Hurricane Fran on September 5, 199623:45 UTC.
▲ Figure 6. Snow cover of eastern United States after the 1996 bliz-zard (POES 1 km image January 14, 1996, 18:20 UTC).
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6 June 1997EARTH SYSTEM MONITOR
The NSIDC EASE-Grid
for a standard, flexible data package,allowing direct comparison of remotesensing products, had been realized atNSIDC.
In 1989, NASA Headquarters re-quested guidance from the scientificcommunity on how to best constructgeophysical products over land surfacesfor Special Sensor Microwave Imager(SSM/I) data and formed a workinggroup to examine the issue. As a result,a prototype Earth grid was developedthrough collaboration between NSIDCand the University of Michigan’s Radia-tion Laboratory. The prototype, calledthe Equal Area SSM/I Earth Grid (EASE-Grid), although specific to the needs ofSSM/I data, held potential for generalapplication to any global scale data set.
Since development, the EASE-Gridhas proven to be so effective thatNSIDC now offers several data sets inthis family of formats. Although thespecific method used to interpolatefrom satellite swath coordinates to afixed earth grid will be unique to eachsensor, the fundamental projection andgridding concept of the EASE-Grid pro-vides the basis for a standard, flexiblegridding method. While the originalEASE-Grid concept comprised two fun-damental parts: 1) a grid and projectionscheme and, 2) a specific method tointerpolate SSM/I data from swathspace to earth gridded coordinates, theterm “EASE-Grid” is now applied to theprojection and gridding scheme alone,independent of the satellite sensor ordata type.
Currently, EASE-Grid is provided ina cylindrical equal area projection (sup-porting full global and mid- to low-latitude studies; see Figure 1) and inseparate azimuthal equal area projec-tions (Figure 2) for the Northern andSouthern Hemispheres (supportinghigh-latitude and polar studies). Itsbasic equal area cell size, 25 x 25 km,can be easily reproduced at higher andlower resolution multiples (e.g., 50 km,12.5 km, 1.25 km).
For example, for NASA’s Polar Path-finder projects, the passive microwavebrightness temperature cell size for allSSM/I channels is 25 x 25 km with anadditional 12.5 X 12.5 km cell size forthe 85 GHz channel. For planned Ad-vanced Very High Resolution Radiom-eter (AVHRR) products, cell size will be1.25 X 1.25, 5 X 5, and 25 x 25 and forTiros Operational Vertical Sounder(TOVS), 100 X 100 km.
The NOAA/NASA Pathfinder Pro-gram SSM/I Level 3 EASE-Grid Bright-ness Temperatures, produced onCD-ROM, were the first NSIDC prod-ucts to benefit from EASE-Grid. Theinterpolation technique employed toproduce the Level 3 EASE-Grid Bright-ness Temperatures maximizes the radio-metric integrity of original brightnesstemperature values, maintains highspatial and temporal precision, andinvolves no averaging of original swathdata. The interpolation process artifi-cially increases (by 16 times) the den-sity of brightness temperaturemeasurements in the satellite swath
Addressing the need for a common, flexible, mapping and gridding scheme
Richard ArmstrongPrincipal Investigator,SSM/I Polar Pathfinder withM. J. Brodzik and A. VaraniNOAA/National Snow and Ice Data Center
The world of geophysical studyentered a golden age with the advent ofremote sensing. Data resources, oncedependent on manual acquisition, in-trepid personalities and field excur-sions, are now large and luxuriatingwith each orbit of the many sensorsscanning heavens and Earth. An abun-dance of data, at a variety of resolu-tions, in every kind of mappingscheme, and in all manner of formats,is now available virtually at the touchof a keyboard.
And therein lies the problem. Sci-entists wishing to compare parametersfor a particular region have no troublefinding data. But the researcher expect-ing to find two data sets coinciding intemporal and spatial resolution, projec-tion, grid size, and data format, suffersfrom impractical optimism. Instead,geophysical data analysis usually de-mands that the required informationfirst be freed from its original organiza-tion, then painstakingly refitted to acommon plan. Only after computation-ally intensive sessions can the compari-sons be quantified and visualized, sothat the work of scientific analysis canat last begin.
For example, researchers at theNational Snow and Ice Data Center(NSIDC) in Boulder, Colorado recentlysought to facilitate studies of seasonalfluctuations of snow cover and sea iceextent by providing a single data setcombining snow and ice data. But thedata selected as the best combinationwere unavailable in a common projec-tion, let alone a common grid or resolu-tion. It was not the first time the need
▲ Figure 1. The cylindrical, equal-area projection used in NSIDC’s EASE-Grid family ofprojections. This projection supports full global and mid- to low-latitude studies.
NOAA/National Snow and Ice Data CenterCIRES, Campus Box 449University of ColoradoBoulder, Colorado 80309Phone: 303-492-6199Fax: 303-492-2468E-mail: [email protected]: http://www-nsidc.colorado.edu
7June 1997 EARTH SYSTEM MONITOR
reference frame (sample interval of 25.0km for 19, 22, and 37 GHz and 12.5 kmfor 85 GHz).
Using actual antenna patterns tocreate the over-sampled array, the neteffect is as if the additional samples hadbeen made by the satellite radiometeritself (i.e., the beam patterns and spatialresolutions of the interpolated dataapproximate those of the originalsamples).
Because response to this first appli-cation of the EASE-Grid was so positive,NSIDC researchers used it to reconcilethe snow and ice extent data discussedabove. Funded by the NOAA Climateand Global Change Program and theNOAA/NASA Pathfinder Program, theNorthern Hemisphere EASE-GridWeekly Snow Cover and Sea Ice Extentproduct (Figure 3) used the digitalNOAA/NESDIS Weekly Northern Hemi-sphere Snow Charts, revised by D.Robinson (Rutgers University). Theoriginal NOAA-NESDIS weekly snowcharts are derived from the manualinterpretation of AVHRR, GOES andother visible-band satellite data. Sea iceextent is based on NSIDC’s polar stereo-graphic sea ice concentration grids,derived from SMMR and SSM/I passivemicrowave brightness temperaturedata.
Snow cover and sea ice extent from
October 1978 through August 1995 arecombined in the data set. Snow coveronly is given for January 1971 throughOctober 1978. (Sea ice data were notavailable prior to October 23, 1978.)
This data set also includes monthlyclimatologies describing average extent,probability of occurrence, and variance.The data are provided in a 25 km grid,
▲ Figure 2. The polar projections used in NSIDC’s EASE-Grid family of projections: Northern and Southern azimuthal, equal-area pro-jections, with full hemispheric coverage—suitable for high-latitude and polar studies.
▲ Figure 3. An example of the Northern Hemisphere EASE-Grid Weekly Snow Coverand Sea Ice Extent product, showing digitized NOAA/NESDIS weekly snow data com-bined with sea ice extent derived from SSM/I, for the week January 2-8, 1995
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World Wide Web and Java-basedremote systems monitoring
Eric OgataADP Support DivisionNational Oceanographic Data CenterNOAA/NESDIS
A set of tools has been developedthat provide near real-time, dynamic,systems monitoring for critical Auto-mated Data Processing (ADP) equip-ment at NOAA’s National Oceano-graphic Data Center (NODC). Thesetools are based on a client/server archi-tecture written in the Java and Perl pro-gramming languages, and are linked toa Web-based, architecture-independentuser interface written in Java. This al-lows near real-time, interactive moni-toring of systems and network statusfrom any machine that can run a Webbrowser and is connected to the NODCIntranet. A simple prototype of such asystem has been developed at theNODC and is currently being used toprovide continuous monitoring of anetwork of approximately 30 UNIXhosts.
The systems status monitor clientprograms are designed to support thecollection of arbitrary system informa-tion and send the information to aserver program at regular intervals. Cur-rently, the systems monitors will sup-port monitoring of Silicon Graphicsand Sun UNIX workstations. The onlysoftware requirement is that the work-station be capable of running Perl 5. Inthe future, support may be provided formonitoring other network devices suchas hubs or routers using Simple Net-work Management Protocol (SNMP).
The systems status monitor cur-rently collects and displays informationabout each host’s hardware configura-tion, operating system version, numberof users, system load, disk capacity (in-cluding the percentage of disk space
selection. If there is a problem that re-quires system administrator interven-tion, information about how toperform common system administra-tion tasks is available from the same setof Web documents.
The monitor software is imple-mented using common, open architec-ture, Internet standards such asHypertext Markup Language (HTML),and Java. This provides an advantageover proprietary implementations,which often have restrictive licensing orhardware requirements limiting thenumber of users or network hosts hav-ing access. By contrast, the NODC sys-
Near real-time dynamic systems monitoring at the National Oceanographic Data Center
used on each localfile system), andmessages in the sys-tem error log file.This information ispresented in agraphical displaythat allows the en-tire network to bescanned to identifyany machines thatrequire attention.Various alert statesare visually flaggedfor each machinewhen a warning oralert condition ex-ists. Some of theconditions beingmonitored includethe following:1. Machine has notresponded for morethan 2 minutes(warning), or formore than four min-utes (alert).2. Machine has beenup without a rebootfor more than 3weeks (warning), orfor more than fourweeks (alert).3. Various keywordsindicating systemproblems arepresent in the sys-tem log file (e.g., error, alert, panic).4. A filesystem is at greater than 90%full (warning), or greater than 95% full(alert).
Further information can be ob-tained about any error conditionsflagged by clicking a button for themachine that has registered an alert.This button brings up a Status Panel forthe particular machine in question. TheStatus Panel indicates the reason for thealert and allows the user to browseitems such as the hardware configura-tion, system load, disk usage, and errorlog. The user may also bring up a loginsession on the machine with a menu
▲ Figure 1. Architecture of near real-time dynamic systemsmonitoring at the NODC.
National Oceanographic Data CenterNOAA/NESDISSSMC3, 4th Floor1315 East-West HighwaySilver Spring, MD 20910-3282E-mail: [email protected]
9June 1997 EARTH SYSTEM MONITOR
tems monitors can be accessed fromany platform connected to the NODCIntranet that can run a Java-capableWeb browser, including most commonUNIX workstations, PCs, andMacintoshes.
System architecture and operationThe systems monitors are imple-
mented as a set of three basic compo-nents. The system components areshown in Figure 1. A client program,written in Perl, is installed on eachmonitored host. The client programwakes up periodically, collects a set ofhost information including systemload, number of users, disk usage andsystem error log entries, opens up anetwork communications channel to aserver program and sends the informa-tion to the server as an ASCII text mes-sage.
The server program accepts connec-tions from the monitored hosts’ clientprograms and maintains a set of persis-tent host objects that process the clientupdate reports and maintain informa-tion about the host’s current status. The
host objects parse the clientupdates into the variouscomponents (e.g., systemload, disk usage, error log),and checks for the presenceof any alarm conditions.The third component is a
Java Applet which can beloaded into a Java-capableWeb browser (e.g.,Netscape). The applet pro-vides an architecture-inde-pendent, highly portableuser interface to the systemsmonitors that can beviewed from any Java-ca-pable Web browser. Mul-tiple servers can be run thatlisten for client reports on
different “ports” (a port is analogous toa “channel” on a radio or television). Aset of hosts can begrouped together byassigning them all to acommon server on thesame port. This could bedone to group hosts ona common network orsubnet, or they may begrouped together basedon some more arbitrarycriteria.
Figure 2 shows atop level display of asystems monitor statuspanel for a collection ofworkstations that are allconnected to the samenetwork hub namedNP3. A button and LEDrepresents the status ofeach host. Green LEDsindicate that there areno problems with thehost. A yellow LED indicates that a hosthas not responded in 2 minutes. A redLED would indicate that a host has not
responded for greater than4 minutes. A magenta LEDindicates that the host isresponding but that there issome alert conditionpresent. For example, the buttonfor a given host in Figure 2indicates that an alert con-dition has been identified.By clicking the button rep-resenting the host, a more
detailed display can be obtained. Thisdisplay is shown in Figure 3. The statuswindow for the host shows alert condi-tions are registered for system log fileerrors and disk usage. This window alsodisplays the system load average for thelast two hours in the rectangular graphat the left. The Syslog button brings upa display of the system error log filewhich is shown in Figure 4.
The system logfile indicates that aprocess (Netscape!) ran out of logicalswap space (memory) and that a filetransfer (FTP) session and a periodic(cron) job ran out of disk space. Bring-ing up the disk usage summary shownin Figure 5, shows that the /dev/rootfilesystem is full. The Login: item fromhost’s Operations menu invokes an Xterminal based login session allowingthe operator to take corrective action.
Other information about this hostis available by clicking on the remain-ing buttons in the host status window(Figure 3). The Config button displays alist of the configuration informationincluding the operating system version,processor type, memory configurationand information about other hardwaredevices connected to this host. TheUptime button in the host status win-dow (Figure 3) displays a message indi-cating the number of days up since thelast system boot.
Current system load and number of
▲ Figure 2. Grey-scale rendition of the systems statusboard for a collection of interconnected workstations.
▲ Figure 4. System error log, accessible through the hoststatus window shown in Figure 3.
– continued on page 10▲ Figure 3. Host status window, which displays alertconditions for a given workstations.
10 June 1997EARTH SYSTEM MONITOR
users logged on is available from theLoad/Users button in the host statuswindow (Figure 3) and is shown in Fig-ure 6. The system load is also displayedgraphically against time in the rectan-gular area at the left of the host statuswindow (Figure 3). The graph showssystem load for the last two hours. Thevertical grid indicates 30 minute inter-vals. The height of the bar indicates theaverage number of jobs queued. Loadcan be averaged over intervals of 1minute, 5 minutes or 15 minutes. TheSettings menu allows the averaging tobe changed between these settings.
This monitor system, while stillvery simplistic, was put together in arelatively short period of time and dem-onstrates the strength of the Java pro-gramming language for rapid proto-typing of client/server distributed pro-grams. Java’s strong set of classes fornetwork and I/O stream programmingallowed this system to be built with arelatively small amount of code (ap-proximately 5000 lines of source code).Although there are much more power-ful commercial monitoring systemsavailable, they often do not provide thedegree of architecture independence
available using theweb-based ap-proach and theycan be much morerestrictive in theirability to be ob-served from anypoint in the net-work due to licens-ing managementcontrols and often,a requirement tobe run on a work-
station that supports the X Windowssystem.
By contrast the “quick and dirty”systems monitor described above pro-vides a relatively high degree of archi-tecture independence and can beobserved from any host that supports aJava capable web browser. Since thesystems monitor applets can be embed-ded in an HTML document, they caneasily be linked directly to online docu-mentation of the NODC Intranet. Thisallows for rapid transition from themonitors to documentation describingcommon systems problems, their solu-tions and in many cases directly to on-
line trouble reportforms for thoseproblems that re-quire vendor main-tenance. Forexample, for thecase above, thesystem logfile indi-cates that a hostprocess ran out oflogical swap space.The same set ofHTML documentsthat contains thesystems monitor
also describes how to add swap space toa system. Had there been a problemthat required hardware maintenance, alink is provided to the maintenanceprovider’s web site and a trouble reportcan be directly submitted.
Error messages from the systemlogfile can be cut from the Syslog win-dow and pasted directly into thetrouble report and also into the log-book for the host that has registered aproblem. The Status Window display(Figure 3) can be embedded as a sepa-rate applet apart from the Status Boarditself. Status Window applets can be
embedded directly into an HTML pagethat documents critical host informa-tion such as IP address, serial number,location, and existing maintenancecontracts. Traditional “stand-alone”commercial monitoring tools wouldoften be much more difficult to inte-grate so closely into an in-house docu-ment set.
ConclusionThe capabilities of this monitoring
system continue to expand as time per-mits. More sophisticated processing ofsystem error log files is near completionat this time. The system is also beingmodified to be much more easily con-figured from a set of editable text filesand to be more easily adaptable forarbitrary network architectures. Thesystem now collects information onNODC Intranet hosts but will soon beavailable for monitoring of hosts out-side the NODC firewall.
Emerging World Wide Web tech-nologies such as Java and HTML enablethe rapid development of distributedclient/server programs. This providesmost of the tools required to developprograms, with a minimal amount ofcoding, that can monitor systems andnetwork status in near real-time andprovide graphic display of status infor-mation to any network computer.
These technologies provide a highdegree of architecture independenceand network accessibility. Since moni-tor applets can be embedded directlyinto HTML documents, they can beeasily linked to system and networkdocumentation. This allows the devel-opment of documents that not onlydisplay the status of many networkhosts, but can also contain explana-tions of how to solve common systemproblems that may be observed. ■
▲ Figure 6. Current system load and number of users loggedon is displayed through a button in the host status window(shown in Figure 3).
System monitoring, from page 9
▲ Figure 5. Disk usage summary.
11June 1997 EARTH SYSTEM MONITOR
The ESDIM Program
rescued.The amount of new data to be
archived is rapidly increasing as newdata collection systems are placed intoservice. These new systems include sat-ellites and NEXRAD weather radars. Toarchive this data, it must be convertedfrom the original media, which is par-ticular to the collection system, to thedata center’s archival media. This con-version is also data rescue.
In recent years access to NOAA’sdata and information has become asignificant area of concentration for theESDIM Program. Access is the process ofmaking available data and informationheld by an individual, office, or organi-zation to a much larger audience. Toaccess data it is necessary to know whatdata is available and where it is located.This is being accomplished by ESDIMwith the online NOAA EnvironmentalServices Data Directory (see the EarthSystem Monitor, December 1996, pp 6-8). The NOAA Directory catalogs the
NOAA-wide program aids data centers in the acquisition and protection of valuable data
Eric DavisEnvironmental Information ServicesNOAA/NESDIS
NOAA is responsible for the collec-tion, management, and stewardship ofa rapidly increasing amount of data andinformation. This data and informationencompasses all of NOAA’s activitiesand includes holdings of climatologi-cal, geophysical, oceanographic, marinefisheries, hydrographic, and carto-graphic records. Much of this data isheld and archived in NOAA’s NationalData Centers: the National ClimaticData Center, the National GeophysicalData Center, and the National Oceano-graphic Data Center. Some of the datais stored by NOAA’s Line Offices or bythe office or scientist who originallycollected it. Data is stored on a varietyof media, but is generally considered tobe of one of three types: paper, film, ordigital.
A NOAA-wide program, the Envi-ronmental Services Information andData Management (ESDIM) Programwas created in response to the NOAAUnder Secretary for Oceans andAtmosphere’s concern about data man-agement in the organization. Datamanagement in NOAA deals with ac-quiring, quality controlling, preserving,storing, and providing user access to itsdata holdings. A study by NOAA’s Advi-sory Panel on Climate and GlobalChange was commissioned in 1989 toreview NOAA’s data management pro-cedures and to make recommendationsfor more effective information manage-ment. The panel’s February 1990 re-port, along with a November 1990 GAOreport, Environmental Data: Major EffortNeeded to Improve NOAA’s Data Manage-ment and Archiving, were the catalyststhat started NOAA’s ESDIM Program inearly 1991.
Originally part of the Office of theChief Scientist, the ESDIM Program was
soon transferred toNOAA’s National En-vironmental Satellite,Data, and InformationService (NESDIS), Of-fice of EnvironmentalInformation Services(EIS), where it is lo-cated today. TheESDIM Program isresponsible for select-ing and funding datamanagement projectsto be accomplished byNOAA. The ESDIMProgram has a smallpermanent staff thatruns the day-to- dayoperations, and ateam of advisors fromNOAA’s Line and Pro-gram Offices that re-views data manage-ment projectproposals and selectsprojects that theESDIM Program willsupport in the upcom-ing year.
During the early years, the ESDIMProgram concentrated on data rescue.Data rescue is the saving or salvaging ofdata (that would otherwise be lost) heldon paper, film, or digital media, con-verting it to a stable, useable media,and then archiving and/or making itavailable for access.
NOAA’s data includes paper recordsfrom the beginning of our country’shistory through the present time. Paperdeteriorates over time, depending onthe physical properties of the paper andthe conditions under which it wasstored. Microfilm and microfiche, usedto rescue deteriorating paper records,are themselves susceptible to deteriora-tion and must be rescued. Digital mediais used to rescue paper and film recordsand to store newly acquired data. Digi-tal media is also susceptible to damage.Data stored on older, less dense mag-netic tapes are being rescued to moredense, smaller sized tape cartridges orto optical media. In time, data storedon today’s best media will have to be
▲ Figure 1. NOAAServer is an ESDIM-supported projectwhich provides WWW access to distributed NOAA data andinformation through a single Web site.
Environmental Information ServicesNOAA/NESDISSSMC3, Room 5509Silver Spring, MD 20910E-Mail: [email protected] – continued on page 12
12 June 1997EARTH SYSTEM MONITOR
The NOAA National Environmen-tal Satellite, Data, and Information Ser-vice (NESDIS) has published a notice inthe Federal Register announcing a newschedule of fees for the sale of its data,information, products, and related ser-vices to commercial users. The new feeschedule will be implemented by NES-DIS elements including the three NOAAnational data centers: the NationalOceanographic Data Center (NODC),the National Climatic Data Center(NCDC), and the National GeophysicalData Center (NGDC). The Federal Regis-ter notice was published on May 7,1997, and the new fee schedule forcommercial users will go into effect 30days later, on June 6, 1997.
Because NESDIS is responsible forpromoting research and education and
because these additional fees wouldhinder these activities by other Govern-mental entities, universities, nonprofitorganizations, and depository libraries,NESDIS has made an exception forthese organizations. It will continue tocharge its existing fees to these organi-zations for their noncommercial use.
The schedule also sets forth feesthat NESDIS will charge for online ac-cess via the Internet. It is anticipatedthat this online capability will begin tobecome operational within a year, andonce available, will provide the meansto satisfy many user requirements atsubstantially reduced cost. The overallfee schedule anticipates that providingthis new access route at lower cost willsubstantially increase the number ofusers to help defray the costs.
The complete text of the FederalRegister notice and the new fee sched-ule are available via the NationalOceanographic Data Center WorldWide Web site (http://www.nodc.noaa.gov/NODC-WNew/newsfedreg.html).
Federal Register notice announces newNESDIS user fee schedule
metadata, or data about the data, forNOAA’s data holdings in Federal Geo-graphic Data Committee (FGDC)
Metadata Standardformat. An onlinesearch for locatingNOAA data, usingany word in the datadescription, can beperformed at theNOAA Directory website, http://www.esdim.noaa.gov/NOAA-Catalog/.
NOAAServer, anESDIM supportedproject (Figure 1)provides Web accessto distributed NOAAdata and informationthrough a single website. Participants inthe development ofNOAAServer includerepresentatives fromall of the NOAA LineOffices. A limited butgrowing portion ofNOAA’s data andinformation is pres-ently availablethrough this systemat http://www.esdim.
noaa.gov/NOAAServer/ ESDIM sponsors projects withinNOAA that meet the goals of the pro-gram in the areas of access, rescue, con-
tinuity, and innovation. An example ofthe projects that were sponsored thisyear is NOAA’s National Ocean Service(NOS) MapFinder (Figure 2). The NOSMapFinder is a major outreach effort, aone-stop Internet service, designed todeliver primary NOS products to publicand private-sector coastal resourcemanagers to assist their planning andmanagement activities. NOS MapFinderwill officially premiere in August 1997and will provide direct Internet accessto NOS imagery and data holdings in-cluding: coastal photography, nauticalcharts, coastal survey maps, environ-mental sensitivity index maps, hydro-graphic surveys, water level stations,and geodetic control points. NOSMapFinder can currently be viewedthrough the WWW at URL: http://mapindex.nos.noaa.gov/.
NOS MapFinder is one of the manysuccessful projects made possiblethrough ESDIM support. Others will behighlighted in future issues of the EarthSystem Monitor. ■▲ Figure 2. Part of NOS MapFinder, an ESDIM-sponsored
project designed to provide direct Internet access to NOSimagery and data holdings. NOS MapFinder will officially de-but in August 1997.
ESDIM, from page 11
13June 1997 EARTH SYSTEM MONITOR
The primarygoals were to in-crease NOAA’s re-sponsiveness tocustomers in thecoastal ocean com-munity and to en-courage theformation of addi-tional partnershipsand joint ventures.Workshop partici-pants received anumber of docu-ments to review, asbackground materialfor the discussions.Several of thesedocuments wereposted on the World
Wide Web.The workshop consisted of a series
of facilitated plenary and smaller work-ing group sessions. The opening ple-nary session included welcomingaddresses by Mr. Robert S. Winokur,Assistant Administrator for Satellite andInformation Services (Figure 1); Dr.Henry R. Frey, Director of the NODC(Figure 2); and Dr. Donald F. Boesch,President, University of Maryland Cen-ter for Environmental and EstuarineStudies. The working group sessionswere structured as follows:• Working Group Session 1Identification of data required to ad-dress national and regional coastalocean issues and scientific researchpriorities. Regional break-out groups:East Coast, Great Lakes, Gulfof Mexico, Islands, and WestCoast.• Working Group Session 2Specific data and informationrequirements. Disciplinarybreak-out groups: Biological,Chemical, Physical, Geologi-cal, and Management.• Working Group Session 3Implementation of the recom-mendations through partner-ships and cooperativeventures. Data source break-out groups: Data and Infor-mation Systems, MilitaryAssets and Proprietary Data,Sea Grant, Universities, and
NOAA Coastal Ocean Data Workshop Shoe-box Data Sets, and State and LocalGovernments.
Each working group session wasfollowed by a plenary session in whicha representative from each group re-ported on its discussions and key rec-ommendations. The plenary sessionsalso provided an opportunity for addi-tional discussion of issues among thegroup as a whole. Many valuable rec-ommendations came out of the work-shop, and rapporteurs took notesduring all sessions to assist with prepa-ration of the final workshop report.
Workshop results will be used to:• increase NODC’s responsiveness tocoastal ocean customer requirements inthe area of data and information man-agement, including customers withinother NOAA programs;• provide additional opportunities forNOAA to form partnerships and jointventures with its partners in the coastalocean community;• increase the knowledge and aware-ness of NOAA’s activities within thecoastal ocean community; and• be responsive to the new Oceano-graphic Partnership Program.
Participants (Figure 3) were veryenthusiastic about the opportunities tonetwork with such a wide range of sci-entists and managers from the U.S.coastal community and to learn moreabout NOAA programs and activities.The final report on the NOAA CoastalOcean Data Workshop was issued inMay 1997 and is accessible through theNODC home page (http://www.nodc.noaa.gov).
▲ Figure 1. Robert S. Winokur, Assistant Administrator forSatellite and Information Services, delivering the welcomingaddress at the NOAA Coastal Ocean Data Workshop.
The National Oceanographic DataCenter (NODC) convened the NOAACoastal Ocean Data Workshop onMarch 11-13, 1997, at the HarborBranch Oceanographic Institution inFort Pierce, Florida. Over 100 scientistsand managers from the U.S. coastalstates and territories and the GreatLakes states (Table 1) attended theworkshop.
Participants represented Federal,state, territorial, and local governmentagencies, academia, and the privatesector, from areas as far away as theCommonwealth of the NorthernMariana Islands and American Samoa.NOAA’s Coastal Services Center, andCoastal Ocean Program, as well as theGraduate School of Oceanography ofthe University of Rhode Island, joinedwith the NODC as cosponsors.
▲ Table 1. Participants in the NOAACoastal Ocean Data Workshop.
Total number of participants: 108Invited Participants: 76NOAA Participants: 30Others (sponsors): 2
Regional distribution of invitedparticipants:
East Coast: 23Great Lakes: 9Gulf of Mexico: 19Islands: 10West Coast: 14
– continued on page 14
▲ Figure 2. Dr. Henry Frey, Director of NOAA’s Na-tional Oceanographic Data Center (NODC).
14 June 1997EARTH SYSTEM MONITOR
EASE, from page 7in an azimuthal, equal area projection(the NSIDC NL EASE-Grid). AnotherNSIDC product, the AARI 10-Day ArcticOcean EASE-Grid Sea Ice Observations,represents a reformatting of informa-tion contained in the Russian Arcticand Antarctic Research Institute’s(AARI) 10-Day Digital Arctic Sea IceCharts. Part of a sea ice data archivedating from the 1930s, the sourcecharts describe sea ice concentration,stages of development and ice forms,integrating visual and instrumental iceparameter data with surface conditionand dynamic processes informationacquired by AARI over approximately10 day periods. The source charts wereoriginally produced through the assimi-lation and analysis of visual and instru-mental aircraft and satelliteobservations.
On sea ice charts, ice parametersare represented by symbols and num-bers giving actual parameter values.(Formerly, symbology varied according
to compiler, but in the 1980s, an inter-national standard for sea ice symbolswas developed and approved by WMO,the WMO Egg Code, and now formsthe basis for the ice charts coding sys-tem.) The original sea ice charts werethen digitized and formatted in SIGRIDformat at AARI, and provided to NSIDCthrough NOAA/ESDIM funding.
The format makes the data difficultto compare and analyze; it is a codeassigning ASCII identifiers to indicateevery kind of mapping information,from the country and service providingthe data, mesh width of the grid, sea iceparameters, location of the data, timeof the record, and on and on, in “lay-ers”. AARI data may not be extractedfrom the SIGRID format without run-ning programs to interpret the codeand get a tabular form of output thatlists grid point locations and data val-ues. Now processed to the EASE-Grid,the AARI data have been condensed tofive layers, and because the EASE-Gridis a standard reference system, it facili-
tates comparative data analysis.Analysts can use standard image
display tools to read data in EASE-Grid.In general, the projection and gridcomponents of EASE-Grid allow usersto easily compare data from differentsensors by superimposing grids. Theglobal coverage presented by the EASE-Grid contrasts with the comparativelylimited grid area of NSIDC’s polar ste-reographic projection, offering broaderpossibilities towards the derivation ofsurface characteristics. With data prolif-eration, and with the growing sophisti-cation of coupled climate and processmodels capable of examining many pa-rameters from multiple instruments, theneed for a standard such as the EASE-Grid grows ever more acute. Like havinga common language, having a commonprojection and gridding scheme inwhich to express geophysical informa-tion is not only useful in comparativeanalyses, but is ultimately tied to thefundamental ability to communicatespatial aspects of scientific studies. ■
Committee on Environmentand Natural ResourcesResearch, 1996. OurChanging Planet—The FY1997 U.S. Global ChangeResearch Program. http://grcio.ciesin.org/ocp97/toc.html
Federal Geographic Data Committee Home Page (information on development ofnational standards forselected types of data andmetadata). http://www.
fgdc. gov/Interagency Taxonomic Information System
(online database of taxonomic informa-tion on flora and fauna from terrestrialand aquatic habitats). http://www.itis.usda.gov/itis/
International Coral Reef Initiative. http://www.nos.noaa.gov/aa/ia/cri.html/
National Oceanographic Data Center DataSubmission Guidelines. http://www.nodc.noaa.gov/NODC-Submit/subindex.html
National Research Council, 1994. Priorities forCoastal Ecosystem Science. http://www.nap.edu/readingroom/books/coast/
index.htmlNational Research Council, 1995. Understand-
ing Marine Biodiversity. http://www.nap.edu/readingroom/enter2.cgi?search (enter search term“marine biodiversity”)
Subcommittee on U.S. Coastal Ocean Science,1995. Setting a New Course for U.S.Coastal Ocean Science, Final Report. http://hpcc.noaa.gov/cop/pubs/suscos/title.html
The following report is not available over theInternet:Inventory of U.S. Coastal Ocean Data: Summa-
ries of Data Sets available from the U.S.National Oceanographic Data Center (inpreparation).
— Rosalind CohenNational Oceanographic Data Center
▲ Figure 3. Dan Schwartz of the Harbor BranchOceanographic Institution facilitates a working group.
Reference materialBackground and reference material were mailedto participants about three weeks prior to theworkshop. Some materials are available over theInternet, including:
call Linda Pikula, AOML and NHC, 305-361-4429, E-mail: [email protected]).Contact: NOAA Library
Near-real time sample productreleased by NSIDC
The Near-real time Ice and SnowExtent (NISE) product passed its first mile-stone on April 25, 1997 with the releaseof the sample product by the NationalSnow and Ice Data Center (NSIDC). Thisglobal map of sea ice concentrations andsnow cover extent is produced from Spe-cial Sensor Microwave Imager passivemicrowave data at 25km spatial resolu-tion. When it becomes fully operational,prior to launch of the NASA Earth Observ-ing System (EOS) AM 1 platform, it willproduce a daily map of snow and iceextent on a global basis, which is the firstof its kind. Currently, two EOS teams areusing the sample product: the Multiangle
NGDC releases first update to NOSHydrographic Survey Data
The first update to the NationalOcean Service (NOS) Hydrographic Sur-vey Data CD-ROM set was issued by theNational Geophysical Data Center(NGDC) in May 1997. This two-disc setprovides the scientific and commercialcommunities with easy, economical, ac-cess to the complete National OceanNOS Hydrographic Survey Digital Data-base. In the last year, an additional 15million soundings have been added to thedatabase, which now consists of over 58million soundings from 5,396 surveys.
Included for the first time are subsetsof multibeam bathymetry Seabeam datacollected by NOS in the 1980s and early1990s. This dataset provides valuableinput to bathymetric basemaps, Geo-graphic Information Systems, geophysicalexploration, coastal engineering studiesand other research projects.Contact: NGDC
NOAA libraries provide historicalstorm information
In late August 1873, a severe stormalong the Atlantic Coast devastated partsof Nova Scotia and Newfoundland, andcaused an estimated $3.5 million in dam-age. However, because it did minimaldamage to the U.S. coast, it has beenreferred to as “the forgotten storm.” Inresponse to a request from a Canadianinvestigator, the NOAA Library was ableto provide information from rare volumes(less than a dozen are known to exist inthe world), and most recently, a summaryof the storm was located in the AnnualReport of the Chief Signal Officer for theyear 1873. This summary of the stormwas entirely unknown to the investigator.For more information, please contactElaine Collins of the NOAA Central Libraryat 301-713-2607 x141.
In addition, as a response to numer-ous requests from students and educatorsfor hurricane related literature and teach-ing aids, Linda Pikula, NOAA Miami Re-gional Librarian and Deborah Fischer, aDade County school librarian, have com-piled three selected lists of hurricane read-ings for: elementary/middle school, highschool/adult, and teachers. A copy of thislist has also been given to the NationalHurricane Center Public Relations Officer.These lists are available on the MiamiRegional Library Home Page at URL:http://www.aoml.noaa.gov/general/lib/ (or
Imaging SpectroRadiometer (MISR) andthe Clouds and the Earth Radiant EnergySystem (CERES) teams. For more informa-tion, please contact the NSIDC User Ser-vices’ Office at:NOAA/National Snow and Ice Data CenterCIRES, Campus Box 449University of ColoradoBoulder, CO 80309Phone: 303-492-6199Fax: 303-492-2468E-mail: [email protected]: NSIDC
NODC places beach temperatureson the World Wide Web
Before surfing the waves this sum-mer, users can surf the World Wide Webto find out just how cold the ocean watermight be. NOAA’s National Oceano-graphic Data Center (NODC) in SilverSpring, Maryland, has placed the averagewater temperatures for the country’sbeaches online to provide useful informa-tion for planning beach activities such asswimming, fishing, or surfing. Water tem-peratures are given for beaches along theAtlantic Coast from Eastport, Maine, toKey West, Florida; along the Gulf Coastfrom Key West to South Padre Island,Texas; and along the Pacific Coast fromSeattle, Washington, to Scripps Pier, Cali-fornia. Water temperature data for PuertoRico, Bermuda, Hawaii, Alaska, AmericanSamoa, Guam, and parts of Mexico arealso included.
The water temperatures presented inNODC’s online “Water TemperatureGuide to Beaches in the United States”are climatological averages based on ob-servations from NOAA’s tide stations anddata buoys. These average water tem-peratures were computed from long-period records ranging from several yearsto several decades, depending on howlong observations had been taken at agiven station.
“Although ocean conditions varyfrom year to year, water temperatures areless variable than air temperatures, sothese averages can provide useful infor-mation for planning beach activities,” saidHenry Frey, director of the data center.The data can be found on the WorldWide Web at http://www.nodc.noaa.gov/NODC-WNew/wtg.shtmlContact: NODC
16 June 1997EARTH SYSTEM MONITOR
Address C
orrection Requested
OFFIC
IAL BU
SINESS
Penalty for Private Use $300
40
POES-AVHRR and TOVS Level 1b format:free for subsetted data sets; visit theSatellite Active Archive online fordetails.
DMSP-SSM/I derived gridded products:free from the NCDC’s home page.
FTP service for many other satellitedata and products are available; pleasecontact the Satellite Data ServicesGroup.
Hard copy AVHRR and GOES ImagesCustom 8” X 10” prints/transpar-
encies are available at $85.00 per im-age; reproduction prints/transparenciesare $25.00 per image. For slides, add$25.00 to the above fees where appro-priate.
Please add $5.00 service and han-dling fee for orders less than $50.00and $11.00 service and handling fee fororders equal to or greater than $50.00.Custom images are created for cus-tomer defined areas, times, and chan-nels. These images are processed fromthe original digital files (level 1b fromPOES and GVAR from GOES) usingMcIDAS image display and processingsoftware. When ordering please specifysatellite, geographic area, feature to beshown, satellite channel (visible or in-frared), resolution, map projection,date and UTC time.
There is no additional cost forgridding and mapping GOES imagesand making standard color enhance-ments. Highly enhanced images may becreated for additional cost. Reproduc-tion images are already available andcan be copied from NCDC’s image li-brary. The majority of these imagesinclude significant events, such as hur-ricanes, blizzards (Figure 6), volcanoeruptions, and forest fires.
Satellite Active ArchiveNOAA’s Satellite Active Archive (SAA)provides easy access to Polar Orbitingsatellite data. The system (available viathe WWW at URL: www.saa.noaa.gov)allows users to search inventories ofselected instrument data, preview rep-resentative Earth images of that data,and to download the data via ftp forfurther processing and analyses.
Data available on the SAA include:
POES AVHRR level 1b data from July 1,1995, to present; POES TOVS level 1bdata from July 1,1995, to the present;DMSP SSM/T1 level 1b, SSM/T2 level 1b,and SSM/I TDR, SDR, EDR data fromFebruary 17, 1997, to present; and TOVSDeep Layer Mean Temperature Productfrom January 1, 1987, to December 31,1994.
Historical GOES Browse ServerEarly in 1997, NCDC added the
Historical GOES Browse Server onlineservices (see URL: www.ncdc.noaa.gov/psguide/satellite/goesbrowse/gb.html). Theserver is unique compared to other sitesoffering satellite images, in that it pro-vides a growing archive of online retro-spective images. The server is primarilyintended to aid researchers performinglong term atmospheric studies involvingsatellite imagery.
Browse imagery at 8 km resolutionis available starting as early as December14, 1996 up to the present, and 24 kmimages are available from October 28,1995 to December 13, 1996. These dailybrowse images cover much of the west-ern northern hemisphere at approxi-mately 0000 UTC (7:00pm EST) and1200 UTC (7:00am EST) for the infraredchannel, and 1800 UTC (1:00pm EST)for the visible channel. Plans includeadding full disk GOES visible and infra-red images going back to the middle of1992.
Special Sensor Microwave/Imager Dataset(SSM/I)
This dataset contains 1.0 degree and2.5 degree time series of the entire SSM/I archive from July 1987 to the present.These monthly average products includeprecipitation, cloud liquid water, totalprecipitable water, snow cover, sea-icecover, and oceanic surface wind speed.The dataset is available online at: http://www.ncdc.noaa.gov/ssmi/html/ssmi.html.■
