Surface Based Observations Section
(formerly Networks and Measurements Section)

Marine Observations in the Bureau of Meteorology

Observations of weather, ocean surface and sub-surface conditions are vital for weather and seasonal climate forecasting and for detecting global climate change. The Bureau operates a number of marine observing networks to provide data for day to day weather forecasting for the public and the marine user communities in Australia. The data are also used internationally as input to computer-based weather and ocean prediction systems, and for supporting seasonal scale climate prediction for events such as El Niño/La Niña in the Pacific.

The data are transmitted around the globe for use by other national weather and ocean services for their own forecasting purposes. The observations are also archived as a long-term record of how the world's climate may be changing.

A specialist Marine Operations Group was established by in 1997 to manage the Bureau's existing and future marine observing networks. The current marine observing networks comprise the Australian Voluntary Observing Fleet, including automated shipboard weather observing systems; the Ship-of-Opportunity Programme; Profiling Float, Drifting Buoy and Waverider Buoy programs. The Marine Operations Group also coordinates the Australian Port Meteorological Agent network

Australian Voluntary Observing Fleet

The Australian Voluntary Observing Fleet (AVOF) is a network of approximately 100 ships recruited to take, record and transmit routine weather observations whilst at sea, and forms part of the international Voluntary Observing Ship (VOS) Scheme.

The AVOF consists of Australian and foreign owned merchant, passenger, fishing and private vessels operating mainly in the Australian region. The Bureau supplies the necessary meteorological equipment and stationery to vessels in the AVOF, and provides the crew with any additional training that may be necessary.

Over 50000 observations are received annually from the ships in the AVOF, with most observations transmitted via the Inmarsat satellite communication system.

Visit the Voluntary Observing Ship website for more information about the global VOS Scheme.

Port Meteorological Agents

Port Meteorological Agents (PMAs) play an important role in the liaison between the Bureau and the shipping community. They are vital in maintaining the Australian Voluntary Observing Fleet and provide valuable support to the Ship-of-Opportunity Programme, as well as the Drifting Buoy and Profiling Float programs.

The Bureau's PMA network, shown on the map below, comprises three Port Meteorological Agents contracted by the Bureau to service the main ports of Sydney, Melbourne and Fremantle.

In the other states of Australia, a limited PMA service is provided by full-time staff from the Regional Observations Sections at the Ports of Darwin, Brisbane, Adelaide and Hobart; and by full-time staff from the nearby Meteorological Offices at Port Hedland, Albany, Cairns, Rockhampton, Mackay, Weipa and Townsville.

The Australian Port Meteorological Agent network.

Visit the Voluntary Observing Ship website for more information about the global Port Meteorological Officer program.

Drifting Buoy Program

The Bureau has been involved with drifting buoys since the First GARP Global Experiment (FGGE) in the 1970s. Between the mid 1980s and 1994, the Bureau maintained a modest buoy program of about six buoys per year, supplemented by an equivalent number of buoys provided by the National Data Buoy Center in the USA, in support of TOGA (Tropical Ocean Global Atmosphere). Since 1995 the Bureau's buoy program has increased to about fifteen Bureau owned and funded buoys per year.

The Bureau's annual buoy deployment plan concentrates mainly on the Indian and Southern Oceans. Two styles of buoys are currently deployed on an opportunity basis from Voluntary Observing Ships and the Royal Australian Navy:

• SVP:  A spherical buoy with a holey sock drogue that incorporates a sea surface temperature sensor as standard. For meteorological purposes, the sensor suite is expanded to include a barometer (SVP-B), or barometer and wind sensors (SVP-BW). Lagrangian current can be derived from all configurations of the SVP buoy.
• FGGE:  Spar type buoy with a weighted line drogue that incorporates air pressure, air temperature and sea surface temperature sensors as standard. In tropical regions the sensor suite is often expanded to include wind speed and wind direction (FGGE-W).

The SVP-B buoy, pictured at right, is becoming the standard drifting meteorological buoy deployed by the Bureau.

Data from drifting buoys deployed by the Bureau are transmitted using the Argos satellite based location and data collection system.

The Bureau also provides logistic support to other agencies participating in the International Buoy Programme for the Indian Ocean (IBPIO), a regional action group of the DBCP.

Visit the Data Buoy Cooperation Panel website for more information about the global buoy program.

Ship-of-Opportunity Programme

The Ship-of-Opportunity Programme (SOOP) is a network of ships that launch expendable bathythermograph (XBT) probes to sample the thermal structure of the upper 800m of the oceans.

The upper ocean data collected by the XBT SOOP is a major reason for our increased knowledge of the interaction between the atmosphere and the oceans. These data provide an indication of major climate events such as El Niño/La Niña. Apart from climate prediction, the data supports other operational requirements (fisheries, shipping and defence) by providing upper ocean data for assimilation in models and ocean analysis schemes.

The Bureau's network, shown on the map below, comprises eight vessels sampling on six lines in low-density or frequently-repeated mode:

• frequently-repeated lines are sampled a minimum of eighteen times per year.
• low-density lines are sampled a minimum of twelve times per year.

Visit the Ship of Opportunity Programme website for more information about the global XBT SOOP.

The Bureau of Meteorology's low-density and frequently-repeated XBT sampling lines.

Profiling Floats

Argo is a global array of 3,000 proposed free drifting profiling floats, designed to measure the temperature and salinity of the upper 2000 m of the ocean.

The Argo array is part of the Global Climate Observing System/Global Ocean Observing System (GCOS/GOOS) and part of the Climate Variability and Predictability Experiment (CLIVAR) and the Global Ocean Data Assimilation Experiment (GODAE).

The floats will continually monitor the oceans and supplement the existing upper ocean thermal (XBT SOOP) networks by extending the spatial and temporal coverage, depth range and accuracy, and enhancing them by providing salinity measurements. Each float operates on a 10 day cycle as shown below, and is expected to last between 4 - 5 years.

The Bureau contributes to Argo through Argo Australia in a joint project with CSIRO Marine and Atmospheric Research. The main float deployment areas for Argo Australia are the Indian and Southern Oceans.

Visit the Argo website for more information about the global profiling float program.

The profiling float cycle.

Waverider Buoy Program

The Bureau operates two Waverider^TM buoys located near Cape Sorell (west coast of Tasmania) and Cape du Couedic (Kangaroo Island, South Australia).

The Cape Sorell buoy was deployed in January 1998 and is supported by CSIRO Marine and Atmospheric Research in Hobart, and the Strahan fishing community. The Cape du Couedic buoy was deployed in November 2000 and is supported by the South Australian State Government's Department for Environment and Heritage.

A Waverider buoy, pictured at right, follows the movements of the sea surface, and determines the wave height by measuring the vertical acceleration of the buoy.

Sea and swell conditions are a major component of coastal and ocean forecasts, but these have largely been estimated in the past and then generally only available during daylight hours. In addition to the Bureau's Waverider buoy network, wave data are also provided by:

• Manly Hydraulics Laboratory, N.S.W.
• Environmental Protection Agency, Qld.
• Department for Planning and Infrastructure W.A.
• Woodside Petroleum Ltd, W.A.
• West Australian Petroleum Pty. Ltd, W.A.
• Australian Water Technologies, N.S.W.
• Esso Australia Ltd, Vic.

For all enquiries regarding the Bureau's Marine Observing Networks, please use our feedback service.