September 1997 EARTH SYSTEM MONITOR NODC Altimetry Lab Tracks 1997 El Niño Operational Program Improves NWS Seasonal Forecasts

Vol. 8, No. 1 ● September 1997 EARTH SYSTEM MONITOR NODC Altimetry Lab tracks 1997 El Niño Operational program improves NWS seasonal forecasts

A guide to Bob Cheney NOAA's data and Chief, Laboratory for information Satellite Altimetry services National Oceanographic Data Center INSIDE NOAA/NESDIS

The TOPEX/POSEIDON 3 (T/P) altimeter satellite, which News briefs was launched in 1992 as a research mission of the American 5 and French space agencies, has The NOAA Central recently become an integral part Library and coastal of NOAA’s operational satellite ocean information system for monitoring the 9 oceans. The transformation was achieved through the efforts of The Earth’s changing NODC’s newest division, the magnetic field on Laboratory for Satellite Altim- record at NGDC etry (LSA), working together 11 with the Jet Propulsion Labora- tory (JPL) and the Naval GOIN: The U.S.-Japan Global Observation Oceanographic Office Information Network (NAVOCEANO). Since late 1996, the highly-accurate sea level 13 observations provided by T/P NASA/NOAA have been available with a delay Prototype Long Term of only two days—fast enough Archive Project to be included in the weekly ocean model run of the Na- 14 tional Weather Service—and NODC’s Internet just in time to follow develop- Security System ment of the 1997 El Niño (Fig- ures 1 and 2). 15 NOAA’s experience with satellite altimetry dates back to Data products and services Geos-3 in 1975. At that time altimeter data were viewed largely as a means of determin- NT OF C E OM TM M ing the marine gravity field, and R E A R P C the program was thus sponsored E E D ▲ Figure 1. A sample series of sea level deviation maps from TOPEX/ ★ ★ by the National Ocean Service’s

U (NOS) National Geodetic Sur- POSEIDON showing evolution of the 1997 El Niño. The data are pro- N A C IT I vided in near-real time (2-day delay) by the NODC Laboratory for E R vey. But as other altimeter mis- D E ST AM sions were flown (Seasat in Satellite Altimetry. Because of their high accuracy (5 cm), the T/P data ATES OF 1978; Geosat during 1985-89) are being assimilated in the NOAA/NCEP model to improve seasonal and new applications were de- forecasts. Sea heights shown are relative to the 1992-95 mean. This U.S. DEPARTMENT veloped, the work expanded to sequence shows the ocean’s response to changes in tropical winds. OF COMMERCE include aspects of physical Sea level drops in the west and rises in the east, producing changes in National Oceanic oceanography such as the Gulf ocean circulation and sea surface temperature which ultimately alter and Atmospheric Stream, sea level variability, and global patterns of rain and atmospheric temperature. For color maps Administration tropical ocean dynamics. In at 10-day intervals, see http://ibis.grdl.noaa.gov/SAT/near_rt/enso/ – continued on page 2 topex_97.html 2 EARTH SYSTEM MONITOR September 1997

30 Topex/Poseidon Sea Level EARTH SYSTEM MONITOR 0Ê N, 94Ê W The Earth System Monitor (ISSN 1068- 2678) is published quarterly by the NOAA 20 (Eastern Pacific) Environmental Information Services office. Questions, comments, or suggestions for articles, as well as requests for subscrip- tions and changes of address, should be directed to the Editor, Sheri A. Phillips. 10 The mailing address for the Earth System Monitor is: H (cm)

National Oceanographic Data Center NOAA/NESDIS E/OC1 0 SSMC3, 4th Floor 1315 East-West Highway Silver Spring, MD 20910-3282

EDITOR -10 Sheri Phillips 1992 1993 1994 1995 1996 1997 Telephone: 301-713-3280 ext.127 ▲ Figure 2. Sea level near the Galapagos Islands in the eastern equatorial Pacific mea- Fax: 301-713-3302 sured by the T/P altimeter. The abrupt, 30-cm rise since the beginning of 1997 indicates E-mail: [email protected] the beginning of a warm, El Niño event. The July 1997 height of 25 cm is as high as DISCLAIMER during the 1982 El Niño, the largest warm event of the century. Mention in the Earth System Monitor of commercial companies or commercial NODC Altimetry Lab, from page 1 ocean eddies and fronts like the Gulf products does not constitute an endorse- 1991 the altimeter program was moved Stream, but they were not sufficiently ment or recommendation by the National to the NOS Office of Ocean and Earth accurate to be used in general circula- Oceanic and Atmospheric Administration Sciences and finally in 1997 to the Na- tion models of the ocean. or the U.S. Department of Commerce. tional Environmental Satellite, Data, This is where the T/P satellite has Use for publicity or advertising purposes of and Information Service’s National provided a breakthrough. In addition to information published in the Earth System Oceanographic Data Center. The LSA is its precision altimeter, T/P carries a Glo- Monitor concerning proprietary products now a leader in many facets of bal Positioning System (GPS) receiver or the tests of such products is not altimetric applications, providing scien- which is capable of quickly determining authorized. tific analyses that range from maps of the position of the T/P satellite to the ocean floor to determination of glo- within a few centimeters. Once the JPL bal sea level rise. team learned how to use the GPS data as Most recently, the Lab’s focus has part of an automated orbit determina- been on improving the operational, tion system, a new era in global ocean near-real time flow of altimetric sea monitoring began. level data. The operational value of al- The present T/P near-real time sys- timetry depends not only on the turn- tem is a model of interagency collabora- around time, but also on the accuracy of tion. JPL receives the raw altimeter data the measurements. from the satellite several times a day ATMOSPH ND ER A IC IC A For example, altimeter data from and forwards them to NAVOCEANO, N D A M E I the European Space Agency’s ERS-1 sat- C N where an interim data set is constructed I O S

L T ellite (1991-96) were processed by A R

and stored. The next day, JPL uses GPS A N T

I O

NOAA in near-real time throughout the data from a global network of ground T

N A N mission, but the quick-look satellite stations plus those from the T/P receiver U .S E . C orbits contained large-scale errors of up to compute a precise satellite orbit. D R E E P M A M to 1 meter. These data were therefore RT O These refined altimeter observations are MENT OF C useful for finding the edges of mid- provided to NOAA’s altimetry lab for further processing. An adjustment is U.S. DEPARTMENT OF COMMERCE Laboratory for Satellite Altimetry first performed to remove large-scale William M. Daley, Secretary National Oceanographic Data Center errors remaining in the data. T/P sea National Oceanic and SSMC3, 3rd Floor, Room 3620 level profiles are then compared to the Atmospheric Administration 1315 East-West Highway previous 4 years of data along the D. James Baker, Silver Spring, MD 20910-3282 same tracks. Finally, 2 days after the Under Secretary and Administrator E-mail: [email protected] – continued on page 4 September 1997 EARTH SYSTEM MONITOR 3

New Lake Erie bathymetry to be NGDC leads successful field displayed in museum News briefs expedition in Greenland A new bathymetric map of Lake Erie Dr. Jonathan Overpeck of the Na- will be displayed in the Great Lakes Sci- tional Geophysical Data Center (NGDC) ence Center in Cleveland, Ohio, during ronmental Assessment Program (OCSEAP) recently returned from southwest the Ohio Lake Erie Conference, September and Processes and Resources of the Bering Greenland, where he led a successful ef- 18 through September 20. The Confer- Sea Shelf (PROBES). What is needed, and fort to survey and sample lakes for use in ence will be hosted by the International what NOAA Environmental Services Data reconstructing past variability in the Joint Commission for the Great Lakes and Information Management has funded circum-Labrador Sea region. This work, the Ohio governor’s Lake Erie Commis- through this project, is a single, stand- carried out in collaboration with the Geo- sion. Focus will be geared toward environ- alone resource that will reference as much logical Society of Denmark and mental organizations, researchers and historical data as can be located. Greenland, focussed on lakes that will Great Lakes representatives, along with Benefits will be immediate and con- yield annually-dated paleoclimate time public officials from local, state, Federal tinuous. Recently the Bering Sea’s eco- series stretching back centuries. These and Canadian governments. The full color nomic and biological significance has series will allow the testing of key hypoth- Lake Erie map will be available from provided impetus for the proliferation of a eses regarding ocean and atmospheric NGDC in October, along with a CD-ROM number of active regional studies includ- variability in the North Atlantic region. containing downloadable imagery and ing: the joint North Pacific Marine Sci- The new time series should also provide data used in the compilation of the ences Organization/GLOBal ocean the first definitive answer to the question bathymetry. ECosystems dynamics Climate Change of whether Norse settlements disappeared and Carrying Capacity (PICES/GLOBEC around AD 1500 in response to climate. NOAA seeks entries for a Bering CCCC) study and the Bering Sea Impacts Sea ecosystem metadatabase Study; national studies (Bering Sea Fisher- NSSDC agrees to participate This inventory of physical and biologi- ies-Oceanography Coordinated Investiga- in GOIN cal data will help researchers, managers, tion, Southeast Bering Sea Carrying Dr. Joe King, director of the National students, fishermen, and the general pub- Capacity, Bering Sea Ecosystem Study); Space Science Data Center (NSSDC), and lic investigate and understand the com- and international research efforts (PICES/ Dr. Herbert W. Kroehl of the National plex ecosystem of the Bering Sea. The GLOBEC, and Japanese and Russian pro- Geophysical Data Center (NGDC), re- inventory will be presented in an indexed, grams); these investigations are directed cently held discussions at the NSSDC on annotated catalog (metadatabase) avail- at understanding the dynamics of the the mutual benefit obtained through joint able through various mechanisms, includ- Bering Sea ecosystem. All of these current participation in the Global Observation ing the World Wide Web (WWW). Those programs have field and data collection Information Network’s (GOIN) space envi- seeking more information or having components associated with them and are ronment pilot projects. Dr. King agreed to knowledge of data that would enhance in a position to contribute to, and benefit send data from the WIND satellite in near the metadatabase are urged to register from, the metadatabase. real-time for inclusion in the retrospective through the WWW at URL http://www. modeling project. The Solar-Terrestrial pmel.noaa.gov/bering/mdb/, or contact Dr. ACCESS Project status Environment Laboratory in Japan will then Bern Megrey, NOAA/AFSC, 7600 Sand The development of the Accelerated model the Earth’s magnetosphere on an Point Way N.E., Seattle, WA 98115, USA, Coastal Community Environmental Sci- hourly basis and share the results with the 206-526-4147, [email protected]. ence Service (ACCESS) Project continues GOIN partners. This will be the first real When completed, the metadatabase to progress. Discussions with Dr. Paul use of the GOIN established network con- will address a serious deficiency identified Dammann of NOAA’s Atlantic Oceano- nections. in 1996 by the National Research Council. graphic and Meteorological Laboratory In their report on the Bering Sea ecosys- (AOML) have focussed on the details of NOAA librarian participates in tem, the council flagged the lack of such a the instrumentation and the implementa- national forum database as the one major impediment to tion of the data operations structure. Dr. The Federal Library and Information studying the Bering Sea. Many different Dammann will draft the list of instruments Center Committee (FLICC), a division of types of physical and biological data have and Michael Crane of the National the Library of Congress, sponsored NOAA been already collected, such as: single- Oceanographic Data Center (NODC) will librarian Doria Grimes in attending the point and gridded time series, repetitive prepare the text of the data capture, data annual meeting of the White House Con- observations from earth orbiting satellites, processing, data distributing and data ference on Library and Information Ser- ocean surveys of physical and biological managing elements. The model for this vices Task Force in Little Rock, AR from oceanographic significance, specimen project is the NASA Pathfinder Program August 7-10, 1997. The results were a re- collections, and historical records of ani- with the active promotion of data distribu- affirmation of decennial White House Con- mal population changes. tion to constituents via the Web and other ferences on libraries, the next one being in Data are available from at least the Internet pathways. The U.S. Environmental scheduled for 2001. Formal liaisons with last century, and in the last two decades Protection Agency is funding this project other library advocacy groups were the the Bering Sea has been the subject of to assure the protection of the reef track secondary outcome. Mrs. Grimes repre- close scrutiny by such major research pro- off the Port of Miami. sented federal libraries at this meeting. grams as the Outer Continental Shelf Envi- 4 EARTH SYSTEM MONITOR September 1997

the western Pacific was unusually low. NOAA Laboratory for Satellite Altimetry joins NODC Because little salinity data are available, the model drifted off substantially, The National Oceanographic Data Center (NODC) welcomes its newest Divi- causing sea level errors in the model of sion: the Laboratory for Satellite Altimetry. The transfer of this group from the NOAA up to 10 cm. But tests showed that as- National Ocean Service to the National Environmental Satellite, Data, and Informa- similation of the altimeter measure- tion Service—the NOAA line office that includes the NODC and the other NOAA ments would have corrected the national data centers—had been pending for more than a year and finally became situation, yielding a more accurate de- official on August 4th, 1997. The Laboratory consists of two groups and several visit- piction of the surface circulation and ing scientists: better seasonal forecasts of sea surface temperature. Color maps of sea level Geophysics: Oceanography: from T/P and forecasts of sea surface Dave McAdoo, Karen Marks, Robert Cheney (Division Chief) temperature through early 1998 can be Walter Smith Laury Miller, John Lillibridge, viewed at http://ibis.grdl.noaa.gov/SAT. C. K. Tai, John Kuhn Click on “1997 El Niño Viewed by Visiting scientists: TOPEX”. Carl Wagner, Femke Vossepoel, Jim Carton TOPEX/POSEIDON is not the first satellite altimeter to monitor El Niño. That distinction belongs to Geosat, The oceanography group specializes in sea level variability as it relates to ocean which captured a dramatic sequence of circulation and climate change, production of high-quality altimeter data sets (such events in the 1980s when the tropical as the new Geosat CD-ROMs), and operational assimilation in ocean models to im- Pacific oscillated between El Niño prove El Niño forecasts. The geophysicists use the same data to derive maps of the (warm) conditions in 1987 to a strong marine gravity field, study the dynamics of the Earth’s crust, and estimate global La Niña (cold) event the following year. ocean bathymetry. Graphics, publications, data sets, and analyses can be found at The Geosat data were initially classified the Lab’s home page (http://ibis.grdl.noaa.gov/SAT), which is already linked to the secret, so the NOAA altimeter lab was NODC Web site (http://www.nodc.noaa.gov). forced to operate in a secure environment at the John Hopkins Applied NODC Altimetry Lab, from page 2 keep the ocean model from deviating Physics Lab. Only after converting the observations were collected, a global too far from reality and result in more secret altimeter data into unclassified record is constructed providing sea accurate forecasts. A specific example measurements of relative sea level level deviations accurate to about 5 was during 1995-96, when salinity in – continued on page 16 centimeters. This operational system provides Geosat Sea Level Deviation Jan 87 an effective monitoring tool for following phenomena such as El Niño, but the real payoff is using the T/P data to improve forecasts of oceanic and atmospheric conditions several seasons in advance. This long-sought NOAA goal has finally been achieved after years of developmental work by the LSA and NCEP (NOAA’s National Centers for Environmental Prediction). Once processed to the level of sea level deviations, the T/P data are transmitted to NCEP where they are combined in a numerical ocean model with other observations such as wind, sea surface temperature, and upper ocean thermal profiles. Ocean conditions are updated each week and, when coupled to an NOAA / Laboratory for Satellite Altimetry atmospheric model, provide the basis -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 for seasonal forecasts of sea surface H (cm) temperature. Assimilation of data from ships and ▲ Figure 3. A view of the Pacific Ocean on January 1987 constructed from Geosat buoys has been ongoing for several altimeter data. High sea level extends 10,000 km along the equator with values up to 20 years but operational use of satellite cm above normal for January. This is the signature of downwelling Kelvin waves, the altimeter data was only initiated at ocean’s response to anomalous westerly winds in the western Pacific NCEP in early 1997. The altimeter data which initiated the 1986-87 El Niño. September 1997 EARTH SYSTEM MONITOR 5 The NOAA Central Library and coastal ocean information Unique historical and modern collections provide a wide variety of coastal information

Albert E. Theberge NOAA Central Library NOAA/NESDIS

The NOAA Central Library serves as a clearinghouse for sources of information for NOAA staff and researchers in the subject fields of oceanic and atmospheric research. On any given day, NOAA Reference Librarians field questions about hurricanes, tornadoes, yesterday’s weather in Sioux City, Iowa, marine fisheries, coastal policies, or marine mining, for example. Some of these questions are answered in-house and others are referred to the appropri- ate agency or individual for response. As the coastal ocean initiatives gain momentum, the information resources of the NOAA Central Library and the satellite libraries of the NOAA-wide library system will play a key role in assisting those searching for this information. The NOAA Central Library can also serve as a focal point to expedite the flow of information among univer- sities, industry, and other government agencies seeking to collaborate on coastal ocean projects. The NOAA Central Library is the direct descendant of the first major ▲ Figure 1. The NOAA Central Library contains thousands of publications from the technical library in the United States, oceanic, atmospheric, and fisheries sciences. The above titles and other coastal science the Coast and Geodetic Survey Library. volumes are available from the Library’s modern collection. It is the flagship library of the NOAA Library System and is uniquely situated cerned with the physical, biological, The NOAA modern collection to provide researchers and policy-mak- geological, chemical, and meteorologi- Two copies of all NOAA publications ers with information concerning the cal aspects of the coastal ocean (Figure such as NOAA Technical Reports, coastal ocean on an unprecedented 1). NOAA Technical Memorandums, and scale. Its collections cover the National Not only does the NOAA Library Special Scientific Reports are found in Ocean Survey, the National Weather system have the most up-to-date infor- the NOAA modern collection. Principal Service, the National Marine Fisheries mation on many of these subjects, but investigators reports on major projects Service, and the Office of Oceanic and it also is the only library in the United such as the Outer Continental Shelf Atmospheric Research. The NOAA Li- States whose historic collections cover Environmental Assessment Program brary is one of the few libraries in the the inception of the Survey of the (OCSEAP) and the California Coopera- world that is capable of meeting the Coast, the establishment of national tive Oceanic Fisheries Investigations needs of integrated research teams con- meteorological observing systems, and (CalCOFI) are included. Publications the beginning of fisheries studies in the from the Army Corps of Engineers NOAA Central Library coastal waters of the United States. The Coastal Engineering Research Center, NOAA/NESDIS collection continues in an unbroken Smithsonian Institution, and Environ- SSMC3, 2nd Floor E/OC4 chain from the beginnings of the ances- mental Protection Agency are also 1315 East-West Highway tral agencies through the NOAA of to- found. Other items of interest are hun- Silver Spring, MD 20910 day. dreds of specialty bibliographies de- E-mail: [email protected] signed specifically for various aspects of WWW: http://www.lib.noaa.gov – continued on page 6 6 EARTH SYSTEM MONITOR September 1997

also resides in the NOAA material, the NOAA Central Library has Central Library, as does a at least 200 pertinent published bibliog- nearly complete set of the raphies that can serve as the beginning Memoirs of the American point for any exhaustive literature Academy of Arts and Sci- search on various aspects of the coastal ences which was first pub- ocean. lished in 1785. Other scientific periodicals dat- Searching the NOAA Catalog ing from the 1800s with The wealth of information available long periods of continu- in the NOAA Library System as related ity include the Proceedings to the coastal ocean is readily apparent of the American Association upon performing rudimentary searches for the Advancement of of the 200,000+ records in the NOAA- Science and Science maga- wide automated catalog, NOAALINC. zine. Modern titles tend NOAALINC is accessible through the to be subject specific such Internet via the NOAA Central Library as the Journal of Aquatic home page (http://www.lib.noaa.gov/). Animal Health (Vol. 1, No. The key words COAST$, ESTUAR$, SEA 1, 1989,) the Journal of GRANT, FISHE$, and MARINE POLLU- Coastal Research (Vol. 1, TION produce significant results in No. 1, 1985,) and the displaying the magnitude of the avail- Journal of Crustacean Biol- able resources. Searches were also per- ogy (Vol. 1, No. 1, 1981,) formed on these terms for the 23 from their beginnings up libraries in the NOAA System and for until the most recent the Silver Spring Central Library. The issue. results are impressive for both the total The available sources resources available through the NOAA ▲ Figure 2. Coastal ocean information is readily avail- of information in the Libraries and the percentage of all titles able through the NOAA Library online catalog, accessible journal collection is virtu- found in the NOAA Central Library at through the NOAA Central Library site at http://www.lib. ally overwhelming for Silver Spring. noaa.gov. investigators desiring to Table 1 displays the number of NOAA Library, from page 5 do literature searches prior to com- works found in listed categories the physical and biological aspects of mencing field research. The value of searched on within NOAALINC. The the coastal ocean, hundreds of proceed- the modern journal collection is en- column labeled ALL LIBRARIES indi- ings of annual meetings, specialized hanced by access to various electronic cates the number of references found symposia, and thematic atlases. bibliographic services; while for older throughout the NOAA Library System

The Journal Collection ▲ Table 1. Results of a selected subject search of NOAALINC. The “$” symbol The NOAA Central Library presently represents a wildcard. subscribes to approximately 400 journals. At least half contain information SEARCH ON ALL LIBRARIES SILVER SPRING of value for coastal ocean researchers FISHE$ 12929 8504 and policy makers. Integrated with the COAST$ OR ESTUAR$ 9212 6506 present active collection are over 2000 SEA GRANT 4056 3584 journal titles that the NOAA Central MARINE POLLUTION 1089 823 Library and predecessor agencies have acquired. As with the growing collec- GREAT LAKES 1052 642 tion of present-day journals, at least GULF OF MEXICO 956 675 half of these are of interest to coastal WOODS HOLE 833 412 ocean researchers. CONTINENTAL SHELF OR SLOPE 624 430 Some series are notable for their CHESAPEAKE BAY 550 370 historical significance to scientific re- SCRIPPS 385 271 search. For instance, the Transactions of the American Philosophical Society are OIL SPILL 347 252 continuous from Vol. 1 (published in PUGET SOUND 294 204 1789) until the late nineteenth century. COLUMBIA RIVER 268 150 A complete set of the Journal of the MARINE MAMMALS 259 158 Franklin Institute from Vol. 1, No. 1, NEW YORK BIGHT 207 169 published in 1826 extending to 1974 September 1997 EARTH SYSTEM MONITOR 7

Institute of Marine Science, the John ▲ Table 2. Indication of geographic range of holdings. The “$” symbol Hopkins Chesapeake Bay Institute, and represents a wildcard. virtually every oceanographic school STATE AND NOAALINC SILVER SPRING with associated laboratories in the (COAST$ OR ESTUAR$) ALL LIBRARIES United States. Over 4000 Sea Grant publications reside in the NOAA Library California 693 414 System with about 85% of those titles Washington 554 289 located at the Central Library. Florida 534 320 Texas 497 428 Historical works on coastal North Carolina 296 227 ocean information Oregon 278 159 • The Central Library houses the com- Alaska 277 204 plete series of the Superintendent’s New York 251 205 Reports of the Coast Survey and Coast Louisiana 218 171 and Geodetic Survey from 1844 on- Mississippi 180 151 ward; a complete collection of Coast Virginia 175 141 Pilots describing the coast and its pecu- Massachusetts 172 122 liarities and anticipated meteorological South Carolina 167 110 conditions in given areas from the mid- Maryland 153 115 1850s onward; special reports describ- Georgia 152 119 ing the evolution of instrumentation Hawaii 146 67 used within the Coast and Geodetic Alabama 120 104 Survey for hydrography, current stud- Maine 114 85 ies, and tide studies; and many scien- Delaware 113 94 tific reports concerning the first Rhode Island 104 81 scientific estuarine studies in the New Jersey 96 64 United States. New Hampshire 47 43 • Historic climatological information Puerto Rico 33 21 includes the complete series of U.S. Connecticut 27 22 Weather Service annual reports begin- Guam 18 11 ning with the Reports of the Army Sig- Virgin Islands 17 14 nal Service in 1871; a complete series of American Samoa 4 2 Smithsonian Institution Reports begin- Michigan 80 50 ning in 1847 which encompass na- Ohio 34 20 tional meteorological observations Wisconsin 23 18 prior to the establishment of a national Illinois 14 11 weather service; and special publica- Indiana 12 10 tions of the Weather Service detailing Minnesota 11 8 the evolutionary trail of weather instrumentation and observing methods. while the column labeled SILVER for the particular search query. The last These are invaluable sources of infor- SPRING indicates the number of hold- six entries in Table 2 are Great Lakes mation for those seeking an under- ings related to the subject matter found states ordered from most available in- standing of coastal changes as related at the NOAA Central Library. formation to least available informa- to climatic changes as the parameters The numbers displayed only repre- tion for the query used to develop the being measured today may not be the sent holdings in the main stacks and do table. ALL LIBRARIES refers to the 23 same as those being measured during not indicate the wealth of material libraries in the NOAA System while the nineteenth century. available within the Journal Collections SILVER SPRING refers to the NOAA • Fisheries researchers will find a com- of the NOAA Library System. Central Library. plete set of the annual reports and Table 2 illustrates the geographic bulletins of the Fish Commission and diversity of the holdings of the NOAA Historical and modern academic works Bureau of Commercial Fisheries begin- Library System. For Table 2 a search was The NOAA Library contains nearly ning from its inception in 1871. These instituted on the state name and complete collections of ocean-related contain observations on commercial (COAST$ or ESTUAR$) as an example of documents from the Scripps Institution fisheries, coastal ecology, coastal ocean a possible search for available informa- of Oceanography, the Woods Hole physical oceanography, and information regarding a given state. Table 2 is Oceanographic Institution, Texas A&M tion on the evolution of techniques ordered from states with oceanic bor- School of Oceanography, Oregon State and instrumentation used by fisheries ders or insular territories with the most University, University of Washington, scientists in measuring fish stocks. information to the least information University of Rhode Island, Virginia – continued on page 8 8 EARTH SYSTEM MONITOR September 1997

United States Navy are indexed and catalogued. Works of the National Academy of Sciences, the Carnegie In- stitution of Washington, and state natural resource agencies are also found in the collection.

Summary The NOAA Central Library and its satellite libraries comprise a unique resource for studies of the Coastal Ocean. Rare historical documents (Fig- ure 3) and data reside in these libraries as well as up-to-date information regarding coastal ocean physical, chemical, geological, and biological processes. A wealth of information concerning economic, social, and cultural uses of the coastal ocean is included. Time line series of data and information from the earliest inception of oceanic studies in the United States in the early 1800s up to the present day are found in the collection. Books, official series and reports of the main line components of NOAA and their predecessor agencies, legal documents and treaties of the ▲ Figure 3. Above left is a page from the oldest book in the NOAA Library collection United States, professional journals, (printed in 1485). Opusculu repertorii prognosticon is a Latin translation of the Greek by atlases, microfilm collections, video Hippocrates, in which he describes how weather affects the human body. Above right is collections, and photo collections that a page from Notes on the Coast of the United States by the second Superintendent of the have information related to the coastal U.S. Coast Survey, Alexander D. Bache. These Notes provided the naval strategy for the ocean (Figure 4) are all found in the Union blockade of Southern ports during the Civil War. NOAA Library system. The NOAA Li- brary System, and particularly the NOAA Library, from page 7 law of the sea. Publications by other NOAA Central Library, is a rich re- • As a Federal Depository for NOAA- governmental agencies related to the source with a wealth of information for related topics, the NOAA Central Li- coastal ocean, such as the United States the coastal ocean investigator. ■ brary contains all current federal laws Geological Survey, the Environmental associated with the use and study of the Protection Agency, the Smithsonian coastal ocean, supporting the evolution Institution, the Army Corps of Engi- of federal coastal ocean policy and the neers, and various elements of the

▲ Figure 4. Dune grasses at Topsail Beach, North Carolina. Photo courtesy of Janice Beatty, NOAA Central Library. September 1997 EARTH SYSTEM MONITOR 9 The Earth’s changing magnetic field on record at NGDC Geomagnetic data bring together a variety of disciplines at the National Geophysical Data Center

Herbert W. Kroehl, Leslie Morris, and Susan McLean Solar-Terrestrial Physics Division National Geophysical Data Center NOAA/NESDIS

The Earth’s magnetic field results predominantly from electrical currents flowing deep within the Earth’s inte- rior, in the upper atmosphere, and in the near-Earth space environment (Fig- ure 1). These currents and associated magnetic field values vary dramatically in time and space. External currents may change the total magnetic field by a few percent within minutes and inter- ▲ nal currents may change the total field Figure 1. An artist’s illustration showing both internal and external sources of the values by a few tenths of a percent per Earth’s magnetic field. year. The techniques used to measure marine surveys. The National Snow and different countries began sharing data. the magnetic fields resulting from the Ice Center archives magnetic data from The first global picture of the Earth’s two sources are essentially independent aircraft surveying the Arctic and Ant- magnetic field as a great magnet was of the platform carrying the instrument arctic. The following describes the mag- presented by Gilbert around 1600. The or magnetometer, whether on a ship, netic data archives at NGDC by first mathematical solution used spheri- plane, satellite or at a ground-based focusing on their different applications. cal harmonic analysis and the first ap- observatory. plication to magnetic field models was The National Geophysical Data Navigation done by Gauss in 1848. Similar tech- Center collects, processes, analyzes, and The discovery of the Earth’s mag- niques to those proposed by Gauss were services geomagnetic data for NOAA’s netic field and its application to “com- refined by Chapman and Bartels in National Data Center and World Data pass navigation” can be traced back to 1940 and are used today to build the Center systems. Geomagnetic data the Chinese around 250 BC (Campbell, standard International Geomagnetic bring together the diverse scientific 1997). Maps or magnetic field models Reference Field (IGRF) models. Figure 2 disciplines represented at NGDC. The of magnetic declination, i.e. the angle shows declination computed from the Solar-Terrestrial Physics (STP) Division between local magnetic and geodetic IGRF 1995 model. These global models focuses on external current systems north or south, became a valuable na- and the annual mean and repeat sta- with high time resolution data from tional resource until scientists from – continued on page 10 GOES and DMSP satellites, magnetic observatories, and variations stations operated for specific scientific cam- paigns. The Solid Earth Geophysics (SEG) Division archives magnetometer data from magnetic observatories and repeat stations and from aircraft and paleomagnetic data used in long-term studies of the Earth’s main field. The Marine Geology and Geophysics (MGG) Division archives include data from magnetometers operated during Solar-Terrestrial Physics Division National Geophysical Data Center NOAA/NESDIS 325 Broadway ▲ Boulder, CO 80303-3328 Figure 2. Magnetic declination as computed from the International Geomagnetic E-mail: [email protected] Reference Field set of coefficients for 1995. 10 EARTH SYSTEM MONITOR September 1997

A. B.

C. D. ▲ Figure 3. A four-panel figure (A through D) showing a session to select and browse one minute geomagnetic data resident in the Space Physics Interactive Data Resource (SPIDR) system from four stations. Geomagnetism, from page 9 affected by changes in the external cur- Geophysicists use magnetic surveys tion data used in the model construc- rents. One minute magnetometer data to assist their exploration for new min- tion are available from the SEG Divi- archived by the STP Division are used eral deposits. “Magnetic anomalies” sion. in the reduction of GPS signals and in indicate changes in the Earth’s struc- Today, magnetic field models are the preparation of magnetic activity ture near the surface where mineral or used in a variety of applications from indices which define times when the oil bearing deposits may have altered resource exploration to antenna align- upper atmosphere is active or quiet. the local magnetic field. Since they are ment. Magnetic field models and looking for “magnetic anomalies”, they onboard magnetometers are used by Geophysical surveys must remove the fields generated by satellite operators to determine the For several decades, land surveyors both internal and external currents. initial attitude of recently launched used a compass-based instrument to The internal or main field is provided satellites, i.e. which way is up? In addi- define the direction of individual prop- by magnetic field models and external tion, Global Positioning Satellite (GPS) erty lines. As time elapsed, the mag- currents are derived from high time systems need the electrical state of the netic declination changed, as did the resolution geomagnetic variations data upper atmosphere as an input to accu- property lines unless the proper adjust- archived by NGDC. rately determine locations and head- ment was made. Frequently, surveyors ings on the Earth’s surface and in query the SE Division archives to cor- Communication space. rect for annual changes in declination High frequency radio waves can be But GPS signals and the derived from the initial survey to the current or used to communicate over very long locations and headings are adversely rerun survey. – continued on page 13 September 1997 EARTH SYSTEM MONITOR 11 GOIN: The U.S.-Japan Global Observation Information Network Joint project aids in bilateral cooperation in Earth observation networks and data exchange

Gerald S. Barton Agency (STA), and Environmental Information Services Gregory Withee, NOAA/NESDIS Deputy Assistant Administrator of In June 1997, NOAA hosted the the U.S. NOAA Global Observation Information Net- National Satellite, work 1997 Workshop. The National Data and Informa- Geophysical Data Center organized the tion Service. The Workshop, which was held at the Na- JPWG is charged tional Center for Atmospheric Research with meeting to atop the Rocky Mountains in Boulder, “identify existing Colorado. The Global Observation In- linkages, to de- formation Network (GOIN) is a joint velop conceptual project between U.S. and Japanese orga- architecture, and nizations to strengthen bilateral coop- to suggest imple- eration in Earth observation infor- mentation strate- mation networks, involving both satel- gies for bilateral lite and in-situ data. In 1993 President and global net- Clinton of the United States and Prime work connectivity. Minister Miyazawa of Japan imple- This work will aim mented GOIN. The GOIN project has to expand links made progress in its goals and has dem- among existing onstrated the results of projects involv- networks on both ing networks, and the exchange of sides to promote atmospheric, oceanographic, land, and global change re- solar-terrestrial data (Figure 1). search, disaster GOIN is part of the United States- monitoring, and Japan Framework for a New Economic other applications Partnership. The goals of the Frame- in support of up- work are “to deal with structural and coming U.S.-Japan sectoral issues in order to substantially cooperative space ▲ increase access and sales of competitive missions, and to Figure 1. The GOIN brochure summarizes program partici- foreign goods and services through facilitate collabora- pants, objectives, and projects. The complete brochure is available market-opening and macroeconomic tion in analyzing online at http://www.ngdc.noaa.gov/stp/GOIN/brochure.htm (re- measures, to increase investment, to and using satellite quires Adobe Acrobat reader). Brochure image courtesy of D. promote international competitiveness, and in-situ data.” Wilkinson, NOAA/NGDC. and to enhance bilateral economic co- NOAA and the operation between the United States STA jointly organized the JPWG. Its proaches, overview software, sharing of and Japan” (Joint Statement on the first meeting was held in Tokyo in Sep- technology, and coordination of net- United States-Japan Framework for a tember 1993 to discuss conceptual ar- work policies. The GOIN work plan New Economic Partnership, July 10, chitecture and existing network relies principally upon existing agency 1993). components. At this meeting the JPWG resources and systems. It provides the The GOIN initiative is imple- established a work plan to identify glo- coordination mechanisms and infra- mented through the Joint Program bal observation information networks, structure required for these existing Working Group (JPWG) with co-chairs to develop estimates of global observa- resources to achieve the goals of the Kenji Okuma, Deputy Director General tion information traffic volumes, and GOIN (Figure 2). of the Japan Science and Technology to establish demonstrations to foster The JPWG pursues the goals of implementation of global observation GOIN through the process of develop- Environmental Information Services information networks. A goal of the ing cooperative test bed network ex- NOAA/NESDIS work plan is to provide a degree of periments using common SSMC3, Room 15448 crosscutting infrastructure by develop- requirements, standards, approaches, Silver Spring, MD 20910 ing connectivity and interoperability and technology sharing. The JPWG E-Mail: [email protected] through the use of common ap- – continued on page 12 12 EARTH SYSTEM MONITOR September 1997

velops are on a voluntary basis. As an ad hoc initiative, GOIN has no direct dedicated funding and emphasizes the use of existing infrastructure and programs in the agencies of the United States and Japan such as existing agency networks and data and information systems. GOIN Projects are focused in four areas corresponding to the Subgroups of the JTWG: Networks, Atmosphere and Oceans, Land, and Solar-Terrestrial. There are pilot projects in each Sub- group. The GOIN 97 Workshop held in Boulder, Colorado in June 1997 focused on reports of the status of the Pilot Project. The Network Subgroup set up special network connections to assure that online demonstrations of Pilot Projects had good connectivity to systems in Japan and the United States. Pilot Projects included atmospheric and oceanographic in-situ data, atmospheric and oceanographic satellite data, solar- terrestrial data, and metadata systems. Several projects showed the scientific applications of many of the instruments from the Japanese Advanced Earth Observation Satellite (ADEOS) such as 700 meter resolution chloro- phyll-a and sea surface temperature data. One of several metadata projects makes available 300 Japanese data set descriptions as a separate node on the NOAA Environmental Services Data Directory. The Land Subgroup discussed new cooperative research institutes in Alaska and Hawaii. The Solar-Terrestrial Subgroup presented two pilot projects that concern near-real time detection of geomagnetic storms and modeling of the near-Earth space environment. The goals of the GOIN agreement ▲ Figure 2. The organizational structure of GOIN, available online at http://www. are being met. The Projects demon- goin.nasda.go.jp:80/GOIN/INTRO/images/fig-1.gif. strated cooperative efforts between many Japanese and U.S. organizations, GOIN, from page 11 participating agencies who work to- demonstrated the interchange of data meets semi-annually to identify exist- gether to identify technical issues, ap- for research uses, and showed increased ing linkages, to develop conceptual proaches, and implementations for use of the networks to transfer large architecture, and to suggest implemen- specific technical issues, e.g., protocols volumes of data across the Pacific in a tation strategies for bilateral and global for network link interoperability. timely manner so that the user can network connectivity (particularly Membership in the JTWG is expected operate in an online, real-time mode. through demonstrations). This work to be flexible and to change over time For information about GOIN, see the implements expansion of the links in order to address the specific techni- WWW Page at http://www.goin.nasda. among existing networks on both sides. cal concerns tasked to it by the JPWG. go.jp:80/. For information about the The JPWG established the Joint The JTWG reports its findings at the GOIN 97 Workshop, see the WWW Technical Working Group (JTWG) to semi-annual JPWG meetings. Page at http://www.ngdc.noaa.gov/stp/ address specific technical issues of con- The GOIN initiative is an ad hoc GOIN/brochure.htm. ■ cern to the JPWG. The JTWG is com- coordination process where participa- posed of technical experts from the tion in GOIN and the programs it de- September 1997 EARTH SYSTEM MONITOR 13 NASA/NOAA Prototype Long Term Archive Project The National Oceanic and Atmo- Upper Atmosphere Research Satellite- prototypical operations into existing spheric Administration (NOAA) and the Micro Limb Sounder (UARS-MLS). NOAA systems. National Aeronautics and Space Admin- NOAA will establish a NOAA Prototype At the end of the demonstration, a istration (NASA) have developed a Archive Facility at NASA GSFC. NOAA report detailing the transfer, archiving, Technical Implementation Agreement will simulate receiving level 1A data and servicing functions will be pre- (TIA) between NASA/Goddard Space directly from the Goddard servicing pared by NOAA and NASA MTPE. The Flight Center (GSFC) and the National facility. NOAA will also simulate receiv- report will evaluate baseline costs and Environmental Satellite, Data, and In- ing satellite derived products from the system needs associated with the archi- formation Service’s (NESDIS) National NASA Distributive Active Archive Cen- val of the MTPE data by NOAA. The Climatic Data Center. The TIA will de- ters (DAAC). The NOAA Prototype report will also evaluate the benefits of velop a prototype to demonstrate the Archive Facility at GSFC will ingest, the collocated archive facility and the functionality of the proposed NOAA/ archive, and provide access to the data rapid availability of the MTPE data. The NASA long term, permanent, archive and products. NASA researchers will prototype will provide data access to for NASA’s Mission to Planet Earth access the data and products from the meet initial USGRP requirements. The (MTPE) data. The project will assist in NOAA facility. The entire process will report will use the prototype experience understanding the complexity and pos- demonstrate the functionality of the to reanalyze these USGRP requirements sible difficulties for NOAA in undertak- long term archive to receive and service and the success of the prototype to ing the archive and service functions data and DAAC developed products. fulfill those requirements. for the MTPE data. This demonstration complements Additionally, projections for vari- With this scenario, NOAA would the NOAA Virtual Data System architec- ous levels of long-term archive effort have a much greater role in the servic- ture with a NOAA facility at NASA and associated costs will be refined by ing of the data to NASA MTPE research- GSFC and the data being serviced from NOAA and MTPE. These will be pre- ers, and the role for NOAA of another location. There will be an sented as additional costs above permanently archiving the MTPE data evaluation phase to ensure suitable baseline, for providing enhanced data could be more complex. This prototype access to and servicing of data and management support services for the is designed to demonstrate the pro- products to meet the general user re- MTPE. cesses involved in acquiring the data quirements of the U.S. Global Change —Wayne M. Faas and products, in limited interoperabil- Research Program (USGRP), NOAA, and National Climatic Data Center ity with users, in working collocated MTPE. NOAA will provide online ser- Federal Plaza with NASA, and in providing rapid ac- vice to NOAA as well as to NASA users. 151 Patton Ave cess to data and products. Under this demonstration proposal, Asheveille, NC 28801 The agreed upon data sets are the NOAA will not develop and implement Phone: 704-271-4296 Total Ozone Mapping Spectrometer- a new data archive, access, and/or dis- E-mail: [email protected] ■ Earth Probe (TOMS-EP) data set and the tribution technology, but will integrate

Geophysics, from page 10 distances. These signals reflect off both short distances. The equatorial iono- other satellites. These signals require the upper atmosphere or ionosphere sphere is the most problematic. The very high data rates and are most fre- and the Earth’s surface. Disturbances in new “cellular telephone satellite sys- quently seen in data from high lati- the ionosphere may result from a tems” will experience similar problems. tudes. change in the electrodynamic structure The ionospheric signature is recorded in of the ionosphere. These changes in the the one minute geomagnetic variations Scientific research external current system are also cap- data. The unique feature of magnetic tured in the magnetic records. A dis- data is that it can record the effects of turbed ionosphere may absorb the Satellite anomalies all electrical currents that may be a very radio wave or divert its path resulting Some of the operational anomalies long distance away from the magne- in a loss of communication. The higher experienced by satellite systems are due tometer. This is both its blessing and its time resolution records available from to the external current systems. As the curse, because the exact location of the the STP Division are used to help deter- satellite is inundated by a stream of current is very difficult to ascertain. mine which frequency to use when energetic charged particles which carry Space physicists use high time reso- communicating between two locations. the external current, one part of the lution geomagnetic variations from Today, satellite communication spacecraft may develop a charge relative satellites and ground-based observato- with ground stations is critical and a to other parts and the discharge may ries to study the occurrence frequency disturbed ionosphere can result in a cause an operational anomaly. The and electrodynamic structure of exter- very temporary loss of the signal. The responsible current system will have a nal current systems flowing in the near- principle problem is a rapid change in magnetic signature that may be seen by Earth space environment. Figure 3 density of the ionosphere over very magnetometers on the ground or on – continued on page 16 14 EARTH SYSTEM MONITOR September 1997

additional RISC 6000 E30 that is config- The NODC’s Internet Security System ured to replace the firewall machine As part of the ongoing effort to breaks the connection between the within a few hours should the firewall upgrade and improve the National secure and non-secure networks. It also machine fail completely. Oceanographic Data Center’s (NODC) means that two daemons are running The NODC also chose to use a Se- computing and communications sys- for each user session thereby increasing cure Net Keycard for those users who tem, the NODC implemented an the work load on the firewall machine. require telnet access to the secure net- Internet “firewall” security system in Proxy is used in conjunction with filter work from the Internet or dial-up. June 1996. The IBM Internet Connec- rules. Each authorized user has an account on tion Secured Network Gateway (SNG) 3. SOCKS - a client-server technology. the firewall machine. When they telnet installed at the NODC serves as a filter Client software (e.g. rtelnet and rftp) in, they are to enter their user name; between NODC’s internal network (se- must be installed on each machine in the firewall machine then answers with cure) and other networks (non-secure) the secure network that needs access to a “challenge” number (instead of a on the Internet. The purpose of the the Internet. A SOCKS server runs on password) and the user enters the chal- firewall is to prevent unauthorized ac- the firewall machine to handle outgo- lenge number on their Secure Card. cess to internal NODC servers. ing telnet and ftp sessions. Telnet and The Secure Card displays an “answer” To provide access to NODC data ftp sessions from the non-secure net- number on the firewall machine and if and information for the general public, work are controlled by filter rules. it is the number that the firewall ma- the NODC mirrors certain data re- The SOCKS server is an emerging chine expects at that instant, the telnet sources and systems on external servers standard for application-level gateways session is established. This does not outside the firewall. The NODC’s sys- that does not require the overhead of a work for ftp sessions as no incoming ftp tem is a bastion firewall, a machine more conventional proxy server. The sessions are permitted. that is placed between the secure SOCKS server is a bastion configuration —Natalie Wong (NODC internal) and the non-secure since the session is broken at the ADP Support Division (Internet) network where the Internet firewall. The NODC chose to use the National Oceanographic Data Center Protocol (IP) forwarding is broken, SOCKS implementation with filter rules NOAA/NESDIS which means no IP packet can go and a private (secure) network. SOCKS SSMC3, 4th Floor through this machine. As the routing is needs to have new versions of the cli- 1315 East-West Highway broken, the only place from which you ent code (known as SOCKSified clients) Silver Spring, MD 20910-3382 can access both networks is the bastion and a separate set of configuration pro- E-mail: [email protected] ■ itself. Therefore, only users who have files on the firewall. The server machine an account on the bastion, with a does not need modification; it is un- double identification (one for the bas- aware that the session is being relayed tion and one for the remote host), can by sockd. use services on both the networks. The NODC SOCKSified clients were There are three ways to use the IBM installed on all machines in the private Firewall software, SNG. The NODC’s (secure) network. The NODC has an design consider- ations included: 1. Filter Rules only - allows all traffic to pass freely subject to specific rules that can allow or deny specific IP packets. 2. Proxy - telnet and ftp sessions from the secure side “talk” to a telnet’d or ftp’d daemon that con- trols the non-secure side. From the non- secure side, a telnet’d daemon “talks” to a secure side daemon. Ftp is not allowed from the non-secure net to the secure net. This technique ▲ Figure 1. The NODC Firewall September 1997 EARTH SYSTEM MONITOR 15

Geomagnetic Data Library online and other agency Web pages, making The National Geophysical Data Data products education a necessary function of techni- Center (NGDC) has completed the pre- cal Web sites. This educational site offers liminary imaging process for the Geo- and services a paleoclimatology science primer and magnetic Data Library (GDL). This project access to a collection of other sites related began in mid-1996, when approximately covering extreme weather events and to paleoclimatology, which detail the use 2200 unique charts from locations world- storms of the past 5 years. Recent addi- of various investigative methodologies wide were transferred from the U.S. Naval tions for 1997 include the March flooding from pack rat collections to coral cores to Oceanographic Office to NGDC. NGDC and tornadoes in the Mississippi and Ohio volcanoes and fossil plant material. The has enhanced the library data base and Valleys, the Northern Plains flooding, and URL is: http://www.ngdc.noaa.gov/paleo/ generated “inventory” images. The gen- the May tornadoes in Texas. It also links education.html. eral character of the original map is cap- to a complete report on the 1996 hurri- Contact: NGDC tured but fine details are not recorded. A cane season, and to NCDC’s latest update prototype version of the WWW search on “Billion Dollar Weather Disasters of Solar Flare Index engine which couples the inventory im- 1980-1997.” Weather event reports can Dr. Tamer Atac and Dr. Atila Ozguc, age and the associated database param- be located at URL: http://www.ncdc. Kandilli Observatory and Earthquake Re- eters has been developed. Approximately noaa.gov/rcsg/weather-events.html. search Institute in Istanbul, Turkey, have 800 of these charts are from U.S. agencies Contact: NCDC sent the National Geophysical Data Cen- and will be made available on NGDC’s ter (NGDC) their daily solar cycle 22 Solar Web site. The remaining images will be Data centers provide new Flare Index, 1986-1996. This index is added as permissions from non-U.S. educational resources online based on earlier work by J. Kleczek of the agencies are obtained. The NOAA Paleoclimatology Program Czech Republic. The importance of a flare Contact: NGDC has created a series of Web pages de- is multiplied by its duration, giving the signed to explain the science of paleocli- total energy emitted by the flare. Daily New service in Seattle matology and current global change sums for the northern and southern hemi- The “Ask a Librarian” service on the issues to lay persons. As the Web has be- spheres are computed, as well as for the NOAA Seattle library web site (http:// come more universal, greater numbers of total solar disk. The NGDC-grouped solar www.wrclib.noaa.gov/lib/) has been re- non-technical users are reaching NOAA flare archive data were used in prepara- vised and is now a referral service to web tion of the indices. The indices will appear CONTACT POINTS sites related to marine and atmospheric in the next issue of NGDC’s publication, science topics. Sidney Stillwaugh, NODC National Climatic Data Center (NCDC) Solar-Geophysical Data, and reside on 704-271-4800 Liaison Officer, has agreed to participate NGDC’s File Transfer Protocol anonymous Fax: 704-271-4876 in the reference service and will aid in E-mail: Climate Services - account of “Solar Databases” for Global routing users to sites pertaining to marine [email protected] Change Models. and atmospheric data (Maureen Woods, Satellite Services - Contact: NGDC E/OC43, 206-526-6241). [email protected] WWW: http://www.ncdc.noaa.gov/ Contact: NOAA Seattle Library National Radar Mosaic online National Geophysical Data Center (NGDC) The National Climatic Data Center NCDC World Wide Web updates 303-497-6419 (NCDC) has placed national WSR-88D Fax: 303-497-6513 The National Climatic Data Center E-mail: [email protected] Doppler Radar (aka NEXRAD) mosaic (NCDC) has implemented a new method WWW: http://www.ngdc.noaa.gov/ reflectivity images on line for web users to for ordering CD-ROM products through a National Oceanographic Data Center browse. Images can be reached through Web-based ordering system located on (NODC) the NCDC web site under What’s New; or the Products, Publications, and Services 301-713-3277 users may go directly to http://www4. section of NCDC’s homepage (http:// Fax: 301-713-3302 ncdc.noaa. gov/cgi-win/wwcgi.dll? www.ncdc.noaa.gov). Customers can now E-mail: [email protected] WWNEXRAD~Images. The images are WWW: http://www.nodc.noaa.gov order all NCDC CD-ROM products produced by Weather Services Interna- through NCDC’s website using their VISA, NOAA Environmental Services tional (WSI) and provided through the Data Directory MasterCard, American Express, or NCDC 301-713-0572 Global Energy and Water Cycle Experi- Open Account. CD-ROMs ordered (Gerry Barton) ment Continental-Scale International through this Web-based system are at a Fax: 301-713-1249 Project (GCIP). Mosaic images are avail- discount price to those ordered via other E-mail: [email protected] able once daily from April 1, 1995 means (such as by phone). This summer, WWW: http://www.esdim.noaa.gov/ through April 18, 1997, and hourly from #data-products NCDC will add their most popular publi- April 19, 1997 to the present time. The cations to the ordering system, and will NOAA Central Library availability of the most recent images is Reference Services: place a new NCDC homepage with im- 301-713-2600 delayed approximately two days to com- proved user interfaces online. Fax: 301-713-4599 ply with copyright requirements. Dick NCDC has also expanded its Web E-mail: [email protected] Cram of NCDC is the coordinator of this page on weather events of 1993-1997. It WWW: http://www.lib.noaa.gov/ effort. now provides quick access to 22 reports Contact: NCDC 16 EARTH SYSTEM MONITOR September 1997 ATTN: Earth System Monitor Silver Spring, MD 20910-3282 1315 East-West Highway Publication Distribution Facility National Oceanic and Atmospheric Administration U.S. DEPARTMENT OF COMMERCE Penalty for Private Use $300 Geosat Sea Level Deviation Apr 88 OFFICIAL BUSINESS Address Correction Requested

NOAA / Laboratory for Satellite Altimetry

-30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 H (cm) ▲ Figure 4. Sea level in April 1988 when values along the equator were 20 cm below normal. Easterly wind anomalies throughout 1988 lowered sea surface temperatures in the equatorial Pacific, creating a cold event known as La Niña. Color versions of Figures 3 and 4 are available online at: http://ibis.grdl.noaa.gov/SAT/gdrs/geosat.html.

NODC Altimetry Lab, from page 4 etry will participate in three upcoming change could the Geosat observations satellite altimeter missions, all of which be released to the general public. All will have operational aspects. The the work was worth the effort, however, Navy’s Geosat Follow-On (GFO) satellite as the images that emerged from in late 1997 will be followed two years NOAA’s Geosat project forever changed later by Jason-1 (the follow-on to T/P) the way in which El Niño and the ocean and the European Space Agency’s in general is perceived. As shown in Envisat. Based on the success of the T/P Figures 3 and 4, El Niño and La Niña are assimilation project, the near-real time global-scale phenomena whose signa- flow of altimeter data to NCEP and tures stretch across the entire breadth of other international weather centers will the Pacific, spanning one-third of the continue to be a priority. ■ Earth’s circumference. The Laboratory for Satellite Altim-

Geophysics, from page 13 temporal resolution; polar or equatorial illustrates a selection and browse session regions; ground-based or satellite-borne conducted from the Space Physics Inter- measurements, etc. The national ar- active Data Resource system. Some of chives at NGDC are able to meet most those studies are conducted by scientists requirements for the stated applications. at NGDC. Geophysicists use magnetic NGDC’s geomagnetic data can be ac- data from ground-based and satellite cessed on the Web at http://www.ngdc. data to study the Earth’s magnetic field noaa.gov/seg/potfld/geomag.html or in and its extension into space. Geologists specific topical areas at http://www.ngdc. use magnetic data to study the structure noaa.gov: 8080 and http://www.ngdc. and evolution of the Earth’s crust. noaa.gov/mgg/geodas/ geodas.html. ■

Conclusion 40 Geomagnetic data are unique and are used in numerous applications re- quiring magnetic models or direct measurements; high temporal or low