Technological Developments and Applications of Data Buoys for Tsunami Monitoring Systems,
Hurricane and Storm Surge Prediction

DBCP Technical Workshop
La Jolla, 16-17 October 2006

Abstracts of the presentations


1.       National Data Buoy Center (NDBC) – 2006 Review

Authors:     Dr. Paul Moersdorf (National Data Buoy Center)

Abstract:    The National Data Buoy Center (NDBC) has undergone explosive growth over the last year:

  • Typical meteorological buoys are being transformed into multi-purpose oceanographic systems,

  • The number of Deep-ocean Assessment and Reporting of Tsunami (DART) buoy network will increase from six to thirty-nine buoys, and will be located in both the Pacific and Atlantic Oceans,

  • The Tropical Atmosphere and Ocean system in the tropical Atlantic is being transferred from NOAA' Pacific Marine Environmental Laboratory to NDBC,

  • NDBC is now an Integrated Ocean Observing System (IOOS) Data Assembly Center (DAC) handling information from over 500 platforms in real-time,

  • The IOOS DAC processes ocean current observations from oil and gas platforms in the northern Gulf of Mexico.

This presentation will report on the current status of these projects and also describe new projects that will become operation in 2007.


2.       The National Oceanic and Atmospheric Administration's Tsunami Program

Author:       Dr. David Green, NOAA Tsunami Program Manager

Abstract:    The Tsunami Program is part of an international cooperative effort to save lives and protect property through hazard assessment, warning guidance, mitigation, research capabilities, and coordination.  Warning guidance is accomplished by tsunami warning centers that acquire observational data from seismic, sea level, and deep-ocean bottom-pressure monitoring networks, process the data to assess the tsunami threat, and disseminate using a variety of communication systems to issue timely and accurate warnings and information bulletins to emergency management agencies and the public.

Currently, NOAA operates 24-7 two Tsunami Warning Centers:  The West Coast and Alaska Tsunami Warning Center (WC/ATWC) in Palmer, Alaska and the Richard H. Hagemeyer Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii.  The WC/ATWC serves as the regional center for the U.S. States of Alaska, Washington, Oregon, and California and the Canadian Province of British Columbia.  The WC/ATWC also has the responsibility for the U.S. Gulf and Atlantic Coasts, as well as the Atlantic coast of Canada. The PTWC is the regional center for the State of Hawaii, the U.S. National center for all other U.S. interests in the Pacific, the international warning center for tsunamis that pose a Pacific-wide threat, and the operational center for the Pacific Tsunami Warning System (PTWS).  The PTWS represents the interests of 29 Member States of the UNESCO Intergovernmental Oceanographic Commission (IOC) that are organized as the Intergovernmental Coordination Group for the Pacific Tsunami Warning System in the Pacific (ICG/PTWS). PTWC and WC/ATWC also provide tsunami warning guidance to Puerto Rico, the U.S. Virgin Islands and serve as interim warning centers for the Indian Ocean and Wider Caribbean Region (WCR).

The National Tsunami Hazard Mitigation Program (NTHMP), a Federal-State partnership program led by NOAA, launched the research and development that resulted in Deep-ocean Assessment and Reporting of Tsunami (DART) technology and associated forecast system science.  DART stations combine bottom-pressure sensing to detect the tsunami wave with acoustic linkage to a moored buoy and satellite communication with operators and researchers, feeding relevant data to NOAA’s Tsunami Warning Centers.

At the time of the devastating Indian-Ocean tsunami in December 2004, the US operated an array of 6 DART stations.  These stations, of a first generation design, were only deployed in the waters of the Pacific.  The data was intended to provide early warning for tsunami threats to the most exposed coastal communities of Alaska, Washington, Oregon, California, and Hawaii.  Over the last two years, the US Administration provided supplemental resources to strengthen and expand the tsunami early warning and mitigation system for all US assets.  As a result, NOAA accelerated the transition from research to operations of a second-generation station, DART II, which is more robust and includes 2-way communication capabilities.  Funding is also being provided to continue research and development of multipurpose and easier to deploy technologies and advance the research to operations transition of the associated site-specific inundation forecast system.  By early 2008, the final operational configuration of the strengthened DART II array will comprise 32 stations around the Pacific Ocean basin and 7 stations in the vicinity of the Atlantic, Caribbean and Gulf of Mexico.  Combined with parallel efforts to strengthen the network of real-time sea level (tide) gauges, broad-band seismic stations, data management and communications, NOAA is establishing a durable and integrated tsunami observing system.

The new data streams provide input to NOAA’s evolving forecast capability, using real-time observations with bathymetric and historical event data, for predicting the propagation and inundation of destructive tsunamis.  The National Tsunami Hazard Mitigation Program and TsunamiReady education and outreach initiatives contribute to the desired outcome of developing resilient communities within a multi-hazard approach.  NOAA’s Tsunami Program achieves this goal by working closely with the United Nations Educational, Scientific, and Cultural Organization’s Intergovernmental Oceanographic Commission (UNESCO-IOC), the World Meteorological Organization (WM), and the Joint Commission on Ocean and Marine Meteorology (JCOMM) to ensure an interoperable and sustainable contribution to the Global Earth Observing System of Systems (GEOSS).


3.      The California Current System: Observations and Comparison with OGCM Solutions

Authors:     Luca Centurioni (Scripps Institution of Oceanography)

Abstract:    SVP drifter data from 1992-2004, AVISO sea level anomalies and NCEP reanalysis winds are used to assemble a time averaged map of the 15 m depth geostrophic velocity in the California Current System seaward of some 50 km from the coast. The wind data are used to compute the Ekman currents which are then subtracted from the drifter velocity measurements. The resulting proxy for geostrophic velocity anomalies from drifters and the corresponding quantity computed from sea level measurements from satellites are combined to form an unbiased mean geostrophic circulation map. The California Current System flows southward with four permanent meanders that can extend seaward for more than 800 km. Zonal jets of alternating eastward and westward zonal currents are connected to the meanders and extend several thousand of km into the Pacific Ocean. The observed time mean circulation and its associated eddy energy are compared to those produced by various high resolutions OGCM solutions:  ROMS (5 km), POP (1/10º), HYCOM (1/12º) and NLOM (1/16º). Simulations in closest agreement with observations come from ROMS, which produces four meanders, geostrophic currents and geostrophic eddy energy that are consistent with the observed values. The time mean ageostrophic velocity in ROMS is strongest within the cyclonic part of the meanders and is similar to the ageostrophic velocity produced by non-linear interaction of Ekman currents with the near surface vorticity field. Since the near surface velocity within 50km of the coast is neither in Ekman nor in geostrophic balance and cannot be sampled by weekly maps of combined satellite altimetry measurements, Lagrangian observations on the continental shelf of the California Current System are necessary. To explain the dynamics of the California Current System its vertical structure needs to be investigated further with observations that extend to depths greater than 500 m.


4.      An Outlook for Arctic Sea Ice

Authors:     Ignatius G. Rigor, Mark Ortmeyer, and Mark Wensnahan  (Polar Science Center, University of Washington)

Abstract:    Understanding the state of the Arctic Ocean is important since changes in the Arctic may foreshadow changes in global climate system. In addition, indeed, the Arctic has undergone dramatic changes in weather, climate and environment. Some examples of Arctic change are:

  • Atmospheric pressure has decreased;

  • Surface air temperatures have increased; and

  • The clockwise circulation of sea ice and the ocean has weakened.

It should be noted that these and many other observed changes in Arctic climate were first observed or explained using data from the International Arctic Buoy Programme (

The extent of arctic sea ice during summer has declined to near-record minima during four of the last seven summers. Can we predict these minima? The presentation will show some of the observed changes in Arctic climate, and relate these changes to the Arctic Oscillation. We will also show how these relationships may help us explain our long-term (1900-present) SAT and sea ice extent records. Finally we will show how these relationships may be used to improve our operational capability to predict Arctic sea ice conditions on weekly to seasonal time scales.


5.      Argo Programme Technical Developments

Authors:     Mathieu Belbeoch, Argo Information Centre (AIC)

Abstract:    Not available.


6.      Thermistor Chain Observations of Heat Content in the Path of Hurricane Rita

Authors:     Rick Lumpkin, Pete Black (NOAA/AOML); Bill Scuba, Peter Niiler (Scripps); Jan Morzel (NWRA)

Abstract:    In September 2005, thermistor chain observations from drifting buoys were collected in the path of Category Five hurricane "Rita".  The observations are analyzed for heat content and its changes during and after passage of the storm.  Evidence of significant cooling before passage of the eye indicates that the storm created a leading cold wake, with the intensity of the wake presumably dictated by both the storm's strength and the prior thermal structure of the ocean.  The complicated interaction of this coupled system must be properly simulated to improve future intensity forecasting, and these observations represent valuable extended time series for calibration and validation of such models.


7.      Surface Drifters in the Southern Gulf of California (Spring and Summer)

Authors:     M. F. Lavín1 and P.P.  Niiler2

1Departamento de Oceanografía Física, CICESE, México.2Scripps Institution of Oceanography

Abstract:    Surface drifters released in the Gulf of California between June 2004 and June 2006 are used to describe the surface circulation in spring and summer.  In June, there is a very strong and narrow (up to 80 cm/s, 40 km) inflowing surface current off the mainland side of the Gulf, which can carry drifters from the entrance to the Upper Gulf in three weeks. By contrast, the drifters in the peninsular half of the Gulf present weak recirculating patterns.  The coastal current lasts a few weeks at most, but transports a large amount of heat into the Gulf, and is probably responsible for the observed advance of the surface isotherms during (climatological) June. Velocity and hydrographic profiles observed with a CTD+LADCP show that the coastal current is geostrophic and reaches to ~400 m depth. In July the coastal current weakens or disappears and eddies (both cyclonic and anticyclonic) become more evident. By August these eddies are the dominant circulation feature, with surface currents ~25-50 cm/s, rotation period ~3-5 days and reaching to depths up to 1000 m.


8.      Australian Initiatives in Integrated Marine Observing Systems

Authors:     Ken Jarrott (Australian Bureau of Meteorology))

Abstract:    A number of proposals are under consideration in Australia to deliver an expanded marine observation infrastructure that will promote the understanding of the country’s ocean environment, coastal ecosystems and marine living resources. 

One major proposal is the Integrated Marine Observing System (IMOS). It has been developed in response to a national Government initiative aimed at promoting investment in broad-scale collaborative research infrastructure, rather than isolated research projects. The IMOS proposal includes the coordinated deployment of multiple sensor networks and related infrastructure for data management and data distribution. Deployed observation technologies are to include Argo profiling floats; moored buoys providing time series observations; ocean gliders and Autonomous Underwater Vehicles; HF coastal radars; acoustic tagging systems and listening stations; and enhanced ground infrastructure for satellite remote sensing. The IMOS governance model builds on partnerships between research institutions, with a central management and coordination agency. 

A second proposal concerns the use of drifting buoys to monitor an important continental boundary current that runs down the East Coast of Australia.


9.      Development of a Platform and Instrumentation for Continuous ocean Observations (PICO mooring)

Authors:     Christian Meinig (PMEL)

Abstract:    The need for time series surface and sub-surface measurements from the ocean has been well stated in many recent reports. Over the past 25 years, arrays of surface moorings have yielded valuable real-time data for NOAA’s missions. However, today’s surface mooring technology has changed very little over these 25 years and requires expensive infrastructure costs including, 1) large and expensive buoys, 2) dedicated ships and highly specialized crew, 3) complex deck operations that are potential dangerous and, 4) limited real-time subsurface capabilities. To meet NOAA’s future requirements and commitments to GEOSS at affordable costs, an alternate surface mooring technology is being developed at PMEL. Many challenges remain, however field tests have been very encouraging and have proven that the PICO mooring concept is viable.


10.    New Developments to Progress the Smart Buoy Idea

Authors:     Motyzhev S.*, Horton E.**, Lunev E.*, Kirichenko A.*, Tolstosheev A.*, Yachmenev.V.

* Marine Hydrophysical Institute NASU/Marlin-Yug Ltd,, Ukraine

** Naval Oceanographic Office, Stennis Space Center, USA

Abstract:    After the DBCP Data Users and Technology Workshop in Reading, UK, in March 2006, the schedules to progress the drifter technology have been revised to address the issues identified in the Recommendations and Actions in the Final Report. Due to these reasons the following developments have been completed in 2006:

  • Modified economical Argos PTT, which allows 30% increase in buoy lifetime;

  • 0.5W Argos PTT with GPS receiver to provide for a buoy some smart parameters, e.g.: self-determination of season and area to choose necessary resolution, establishment of real-time clock inside a buoy, etc;

  • New 80-m temperature chain with additional depth sensors to check the model, describing the chain profile in shear currents;

  • Modified barometric port with decreased time inertia to be ready for AP measurements right after submergence;

  • Testing of new barometric port with 34-cm hull to develop the compact, reliable as for AP measurements, cost-effective drifter capable of automatic self-deployment.

A few clusters of drifters were built according these goals and deployed in the Black Sea and other areas of the Ocean. The analysis of preliminary results is demonstrating that new ideas are working according to the prospective applications.


11.    Next Generation DART Developments at NOAA/PMEL

Authors:     Christian Meinig (PMEL)

Abstract:    NOAA’s Pacific Marine Environmental Laboratory has developed and deployed next-generation DART systems in support of the tsunami monitoring research effort. The goal of the development is maintain DART II functional capabilities while significantly improving global deployment opportunities by reducing ship requirements and the need for highly trained staff. Additionally, the design includes “factory built” concepts, an integrated BPR/buoy package and attempts to include vandal protection features. Time series data from a test system deployed within 100nm of an operational DART II buoy show favorable results including the capture of a small tsunami on each system. The high-frequency data of the tsunami was recovered via the bi-directional link and overall data rates for the three-month test period exceeded 98%.


12.    Acoustic Profiler Applications

Authors:     Mark Bushnell (NOAA / NOS Center for Operational Oceanographic Products & Services), Acoustic Profiler Applications

Abstract:    We have two recent accomplishments that may be of interest to the DBCP:

  • Fastening acoustic current profilers to standard US aids to navigation, and
  • Demonstration of a Quick Response Estuarine Buoy (QREB) fitted with an acoustic current profiler and met sensors. 


13.    International Ocean Observing System (IOOS)

Authors:     David Zilkoski (NOAA)

Abstract:    Not available.


14.    Argos Performance in the European Region

Authors:     Bill Woodward (CLS America), Philippe Gros (CLS), Christian Ortega (CLS)

Abstract:    Argos users have reported a reduction in the number of error-free messages received from PTTs transmitting in the Mediterranean/European region. This has prompted a systematic investigation by CLS and CNES of possible reasons for this reduction in performance. The investigation is centered on two objectives: 1) Estimating the mean level of noise in the European Region and, 2) Seeking the locations of discrete noise sources.

The approach is both technical and administrative. The technical side includes specific satellite-based measurements as well as the development of some analytical tools that are now available to help Argos users optimize their PTT communications through careful selection of parameters such as transmission frequency, output power and, transmission protocol as a function of the deployment area.  Administratively, action has begun via the CLS parent organization, CNES, the French Space Agency, to resolve specific sources of interfering noise that have been identified and documented.

This presentation will describe the measurements that have been made and conclusions drawn from them, the transmission optimizing tools that are now available from CLS and how users can access them and, the anticipated next steps in this investigation.


15.    Global Drifter Program Assessment of Drogue Presence of Surface Drifters

Authors:     Jessica Redman  (NOAA Physical Oceanography Division)

Abstract:    The GDP recently determined that drogue presence of a number of drifters had been misdiagnosed due to manufacturer dependent behavior of submergence sensor or misinterpretation of tether strain.  Consequently, we conducted a major revaluation of drogue presence in all surface drifters deployed from 1998 onwards.  This talk will explain how this evaluation was done, as well as provide suggestions for future drogue detection sensors based on observations and results from the revaluation.


16.    Iridium Communications for Data Buoy Applications

Author:       David Meldrum (Scottish Association for Marine Science)

Abstract:    Over the last few years confidence has grown in the use of Iridium as a satellite communications channel for data buoys, and Iridium-based products are starting to emerge onto the marketplace. Nonetheless, further experience and evaluation is necessary before operational users will make wide use of the system. This paper describes recent polar deployments of Iridium equipped systems by SAMS, and examines some options for the way forward.


17.    Comparison Study of Drifters from Four Manufacturers

Authors:     Rick Lumpkin, Craig Engler and Mayra Pazos (Drifter Operations Center)

Abstract:    The Global Drifter Program is continuing a comparison study of SVP drift buoys built with the mini drogue.  The ongoing study compares the performance of the drifters: transmitter failure rate, submergence or strain sensor performance, drogue lifetime, SST thermistor performance, and anomalous behavior with respect to other drifters in the cluster.

In 2005 eight clusters of four drifters, one from each manufacturer, were deployed.  Final results from the 2005 study will be presented.  In 2006 a total of seven clusters will be deployed in open Atlantic Ocean regions. Results will be discussed at the workshop.


18.    Argos-3: An Update

Authors:     Bill Woodward (CLS America), Philippe Gros (CLS), Christian Ortega (CLS)

Abstract:    The first Argos-3 system scheduled to be launched on the EUMETSAT Satellite METOP 1 on October 7, 2006 will bring Argos users significant new capabilities for data collection. This presentation will remind users about the new features which include a high data rate channel and two-way communications, and give some application-specific examples of the benefits of using Argos-3.  The Platform Messaging Terminal (PMT) “giveaway program” will also be described as well as the current schedule for future launches of satellites carrying Argos-3 systems.


19.    Next Generation Argos Capability

Authors:     Michel Faup (CNES)

Abstract:    Feedback will be presented of a recently organized Argos users satisfaction survey issued by CLS and from the conclusions of a NOAA independent investigation of high-level Argos users focusing on identifying current or future user requirements that may be unfulfilled by the Argos-2 and Argos-3 instruments. From this input, CLS derived the user needs for the period 2013-2020 (the time frame of the NPOESS C1 and C2 lifetime). A synthesis of this analysis will be presented.

The presentation will finally focus on the improvements of the Argos system and of the Argos new generation instrument that CNES identified to allow it to satisfy most of the future user needs. Even if the new generation will be based on the same general principles than Argos-3 in term of orbits (LEO), access mode (frequency and time random access) and bandwidth (UHF in 401-402 MHz band) in order to keep the main advantages of the system (frequency regulation issues, favourable link budget, small size of beacons and antennas, etc.), it will include, thanks to a very important technological step in term of processing capability, a large increase of the number of frequency channels) and processing units (mainly for the high data rate beacons @ 4800 bps), and an important reinforcement of the downlink.