The ENSO Signal
The ENSO Signal – Issue 14, May 2000

Articles of Interest to the ENSO Community

Articles of interest to the ENSO community
gleaned from publications or submitted by readers.

  1. ESIG's Second Issue of the ENSO Signal
  2. Omnet's SCIENCEnet
  3. Pacific Decadal Oscillation (PDO)
  4. IRI Agricultural Applications Program
  5. Using Pleiades To Predict El Niño
  6. NAS Brochure Available
  7. Fellowship Opportunity
  8. Hooke To Join AMS
  9. WMO, IADB, and SOPAC
  10. OWL
  11. Current State Of The Tropical Pacific: Cold Phase
  12. East Pacific SSTs and Sea Level
  13. ENSO in 2000?
  14. Maps Of Spanish Exclusive Economic Zone
  15. US River Data On Internet
  16. USGCRP Seminar Series
  17. El Niño Mass Media Index


ESIG's Second Issue of the ENSO Signal

This is the Environmental and Societal Impacts Group's (ESIG) second issue of the ENSO Signal. We hope to provide the community interested in El Niño and La Niña a glimpse of activities that may connect researchers in various fields with one another. In large measure, the ENSO Signal relies on feedback from its readers. Please email us at or contact D. Jan Stewart, Managing Editor, ENSO Signal, ESIG/NCAR, PO Box 3000, Boulder, CO 80307 USA; tel: 1-303-497-8134; fax: 1-303-497-8125.

Please note that the ENSO Signal's on-line address has changed since our last issue:

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Omnet's SCIENCEnet

SCIENCEnet is a communications nexus that has been provided for the marine, aquatic and atmospheric sciences research community by Omnet, Inc. in Staunton, Virginia, USA. Since 1980, SCIENCEnet has been the standard whereby ocean and atmospheric research scientists communicate worldwide, collaborating on research projects.

A few years ago, with funding from NASA and the US Office of Naval Research and the cooperation of a number of professional societies, Omnet converted SCIENCEnet from a proprietary email and bulletin board network to a password-protected intranet.

The heavy increase in user traffic and the growth of the database is taking its toll on system performance. With limited resources, Omnet is doing what it can to improve and upgrade the system and is committed to maintaining SCIENCEnet as a public service for the community as long as it can.

Member accounts for access to SCIENCEnet are free to the professional ocean and atmospheric research community. SCIENCEnet includes access to its more than 11,000-member searchable directory. This directory is the most up-to-date and accurate directory of marine and aquatic scientists available anywhere. For an account, send complete address information to and an account will be set up promptly.

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Pacific Decadal Oscillation (PDO)

The PDO is a long-term fluctuation of Pacific climate, in many ways a long-lived relative of the El Niño-Southern Oscillation. It waxes and wanes approximately every 20 to 30 years. Some scientists speculate that the atmosphere has just begun to enter the negative phase of the PDO characterized by lower-than-normal sea surface heights and ocean temperatures in the eastern equatorial Pacific and higher-than-normal sea surface heights connecting the north, west, and southern Pacific. The negative phase should steer the jet stream further north over the western United States. The positive phase appears to have lasted from 1977 through 1999 (see graph).

The term PDO was coined in the mid-1990s by Steven Hare at the University of Washington. He, along with colleagues Nate Mantua, Yuan Zhang, Robert Francis and Mike Wallace described the phenomenon as part of their work on fish population fluctuations. The PDO has also been described as a long-lived El Niño-like pattern of Pacific climate variability. The causes for the PDO are not currently known, but because of its apparent strong tendency to last for several decades, successful forecasting of the PDO may assist scientists in ENSO forecasting as well.

The PDO Index is defined as the leading principal component of North Pacific monthly sea surface temperature variability (poleward of 20 degrees N for the 1900-93 period). For more information, please contact Nate Mantua ( or Steven Hare ( Mantua updates the PDO index every two to three months.

Time Series of the SST-Based Monthly PDO Index

For PDO information and related research, see the following links:
(The graphic above and most of the information herein is taken from this Web site.)
Topex-Poseidon is a satellite that measures the precise shape of the ocean's surface and JPL has created its own PDO page.
A brief overview for the non-specialist, to appear in Encyclopedia of Environmental Change.

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IRI Agricultural Applications Program

The International Research Institute (IRI) for climate prediction has developed a strategy for agricultural applications. Seasonal climate forecasts make it possible to adjust decisions to reduce unwanted impacts and take advantage of favorable conditions. The strategy provides an overview and guidelines for IRI efforts to enhance society's capability to apply predictions of seasonal climate fluctuations to improve the sustainability of agricultural production, distribution, and consumption systems. Agricultural application efforts will be directed toward four themes: (1) refinement of IRI forecast research and products; (2) development of tools and methods; (3) regional-to-local application to food production, and (4) global-to-regional food security alert and response. For more information, see the Web site at or contact the IRI at Lamont-Doherty Earth Observatory, PO Box 1000, Palisades, NY 10964 USA; tel: 1-914-680-4468; fax: 1-914-680-4866.

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Using Pleiades To Predict El Niño

In a letter to Nature, Benjamin Orlove, John Chiang and Mark Cane reported that observations of changes in the apparent brightness of stars in the Pleiades around the time of the southern winter solstice was used to predict interannual variations in summer rainfall and the autumn harvest. Researchers have found that the farming tradition, which extends as far back as the fifteenth century, used the poor visibility of the Pleiades in June (caused by an increase in subvisual high cirrus clouds) to forecast reduced rainfall during the growing season several months later. Three other attributes were also used to forecast the timing and quantity of rains and to estimate the size of the harvest. For more information, see: Orlove, B.S., J.C.H. Chiang, and M.A. Cane, 2000: Forecasting Andean rainfall and crop yield from the influence of El Niño on Pleiades visibility. Nature, 403, 68-71. or contact Orlove at

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NAS Brochure Available

El Nino and La Nina: Tracing the Dance of Ocean and AtmosphereIn March 2000, the US National Academy of Sciences (NAS) produced El Niño and La Niña: Tracing the Dance of Ocean and Atmosphere in March 2000 to explain the basic science of ENSO. It includes a chronology of events in the history of understanding ENSO. Roberta Conlan and Robert Service wrote the booklet for NAS's Office on Public Understanding of Science. This booklet is available free of charge by writing to National Academy of Sciences, Office on Public Understanding of Science, 2101 Constitution Ave. NW, Washington, DC 20418; tel: 1-202-334-1575. It is also available on the Web at or email:

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Fellowship Opportunity

A collaborative effort between the American Fisheries Society, the National Sea Grant Office, the National Marine Fisheries Society, NOAA's Office of Global Programs, the American Geophysical Union (to name just a few of the collaborators) is scheduled to begin about 1 August 2000. This 18-month effort will employ a Fellow whose main responsibility will be to organize a symposium at the 2001 AFS Annual Meeting on the impact of climate on living aquatic resources (both marine and freshwater) and handle the subsequent publication of the proceedings. The announcement for this fellowship appeared in the AFS Fisheries Magazine for more information. Closing date was originally scheduled for 1 June 2000, but more applications are being sought. For more information, see the Web site or contact: Gus Rassam, Executive Director; American Fisheries Society, 5410 Grosvenor Lane, Ste. 110, Bethesda, MD 20814 USA; email:

American Fisheries Society

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Hooke To Join AMS

William (Bill) Hooke, Director of NOAA's US Weather Research Program, will join the AMS (American Meteorological Society) as a senior policy fellow and associate director of the AMS's Atmospheric Policy Program, beginning 5 June 2000. This program, which was begun in October 1999, is designed to foster research, education, and discussion about issues and policies related to the atmospheric and oceanic sciences. For more information about the program, please contact the American Meteorological Society, 1200 New York Ave. NW, Suite 410, Washington, DC 20005 USA; tel: 1-202-682-9006; fax: 1-202-682-9298.

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The World Meteorological Organization (WMO) has signed MOUs (memoranda of understanding) with the Inter-American Development Bank (IDB) and the South Pacific Applied Geoscience Commission (SOPAC) to develop cooperative activities in order to develop strategies to mitigate natural disasters, a number of which can be related to ENSO. Joint workshops, data collection, natural disaster management and national capacity building are just a few of the expected outcomes from these collaborations. For more information, contact WMO, 7 bis Avenue de la Paix, CP2300, 1211 Geneva 2, Switzerland; tel: 41-22-730-8111; fax: 41-22-730-8181; or email: (from AMS Newsletter).

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The Ocean-Weather Laboratory (OWL) has recently been approved to be the new laboratory of the University of Philippines in Visayas. The laboratory will serve as an environmental guidance center specializing in oceanographic and climate studies, and will conduct research and extension activities. The Philippines are affected by both the cold and warm extremes of the ENSO cycle. The lab is currently looking for help in various forms (funding, equipment, collaboration). Those interested in small-scale coastal oceanography, marine, and fishery sciences, please contact R. Baleña, PO Box 249, Iloilo City 5000, Philippines; tel/fax: 63-33-3158378; email: (from SCIENCEnet).

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Current State Of The Tropical Pacific: Cold Phase

(From Climate Prediction Center, Diagnostic Advisory 2000/5) The large-scale oceanic and atmospheric circulation patterns continued to reflect La Niña conditions in the tropical Pacific during April. Consistent cold episode-related oceanic features include: below-normal SSTs in the western and central Pacific, and above- (below-) normal subsurface temperatures in the western (eastern) equatorial Pacific. Despite the persistence of many La Niña-related features, SST anomalies have been increasing during recent weeks throughout most of the eastern equatorial Pacific, which has resulted in substantial increases in the Nino3.4, Nino3, and Nino1+2 indices since mid-February 2000 and in the appearance of positive SST anomalies between 80 W and 120 W. Weekly updates for SST, 850-hPa wind, and OLR are available on the Climate Prediction Center Web site at (Weekly Update). For more information, contact Climate Prediction Center, NOAA/NWS, W/NP52, Rm 605, WWB, 5200 Auth Rd., Camp Springs, MD 20746-4304; email:

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East Pacific SSTs And Sea Level

April sea surface temperatures (SSTs) and sea levels persist below normal along the Peru coast (Callao), but otherwise continue to track the climatological trend. At the equator, anomalies have returned to zero (SSTs) or have become slightly positive (sea level). For the data, see SCIENCEnet at or contact The information is also available on the Web at

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ENSO IN 2000?

C.K. Gopinathan, Physical Oceanography Division of the National Institute of Oceanography, Dona, Paula, Goa 403044, India, posted the following abstract on SCIENCEnet:

Several models have been developed over the last few decades to predict the advent of a new ENSO several months in advance of the actual event. None of the models have predicted a warm event in the year 2000. However, a model based on Canonical Correlation Analysis predicts an increase in SST anomalies of 1°C in the Niño3.4 region by September 2000.

Observations of SST anomaly changes in the eastern equatorial Pacific between longitudes 90 W and 120 W strongly suggest that the cold phase which followed the 1997-98 event is being rapidly replaced by the warm phase. The current trend of increasing SST anomaly in the eastern equatorial Pacific may lead to the development of a new ENSO event during 2000, according to this researcher.

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Maps Of Spanish Exclusive Economic Zone

IEOThe EEZ (Spanish Exclusive Economic Zone) Program is conducting a systematic mapping to allow the compilation of a series of detailed bathymetric charts of its EEZ. The program is directed and managed by the Instituto Español de Oceanografía (IEO) and the Instituto Hidrográfico de la Marina (IHM). Begun in 1995, the program first studied the Western Mediterranean and moved in 1998 to the Canary Islands. The program is also conducting a geophysical survey to determine the origin of the geo-morphology from the maps, as well as sampling and measuring the physical characteristics of the water column in the EEZ area. The IHM will also publish Canary Islands maps. For more information, contact or the IEO's Web site (in English and Spanish) at or the IHM (in Spanish) at Mail addresses are: IEO, Avda. de Brasil, no. 31, 28020 Madrid, Spain; and IHM, Tolosa Latour s/n DP 11007, Cadiz, Spain (from SCIENCEnet).

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US River Data On Internet

Mississippi River BasinsDaily river forecasts and flood stage information from the nation's largest river basin are now available on the Internet. This information has been consolidated and put on the Web by the US National Weather Service. The site is called "River Watch" and contains water level data, flood stage parameters, and forecasts for all of the Mississippi River Basins's main stem rivers, including the Ohio, Illinois, and Missouri Rivers, as well as the upper and lower Mississippi. For more details and the actual forecasts, see the Web site at (from AMS Newsletter).

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USGCRP Seminar Series

The USGCRP (US Global Change Research Program) has a seminar series designed to encourage consideration of important research findings. Each session offers a presentation and discussion of a topic drawn from the latest scientific studies of the global environment and its interaction with societal activities. Several of these seminars will be of interest to readers of the ENSO Signal. The topics and speakers are selected for interest to a wide audience, and the public is invited to attend. Within a few days of the seminar, it is posed on line and is available for review. All five years of previous seminars are available as well. For more information, contact Anthony Socci, Associate Director, USGCRP, 400 Virginia Ave. SW, Suite 750, Washington, DC 20024 USA; tel: 1-202-314-2235; fax: 1-202-488-8681; email:; Web site:

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El Niño Mass Media Index

Steven Hare (University of Washington) has gathered media information on El Niño information in the media and has compiled an El Niño Mass Media Index which compares media reports on El Nño to the Southern Oscillation Index. He prepared this interesting graphic. For more information, contact Steven Hare at the International Pacific Halibut Commission, Box 95009, University of Washington, Seattle, WA 98145-2009; email:

El Niño Mass Media Index

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To submit an item to appear in the Articles of Interest to the ENSO Community section, please use the on-line form in the Comments and Feedback section, or send an email to Information to be included in the next issue of the ENSO Signal must be received by 31 July 2000.

Environmental and Societal Impacts Group
National Center for Atmospheric Research
PO Box 3000, Boulder, CO 80307 USA
Tel (303) 497-8117; Fax (303) 497-8125

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