Introduction

Introduction

The Bureau of Meteorology Research Centre (BMRC) commenced in January 1985 and so 2004 is the twentieth year of operation for BMRC. Over the last twenty years BMRC has grown both in size and scope in order to fulfil the Bureau's statutory responsibility to advance meteorological science. The advancement of the science has been complemented by the continuing enhancement of the Bureau's operations and services through the development of sophisticated systems and techniques. The establishment of strong links with the international research community has been a key strategy in ensuring that these complementary objectives are met effectively. While interaction with the global community has been important, the BMRC has also promoted the application of meteorological science for the general good of the Australian community through collaboration with other research and user groups.

The activities in BMRC involve a balance of strategic and applied research, with pure and strategic research providing the foundation for more applied research and development on problems arising from the operations of the Bureau and from the broad national community. The BMRC activities also extend from field projects, especially associated with the research site in Darwin, to diagnostic and theoretical studies, as well as a major focus on modelling across the research sub-programs of weather, climate, ocean, and hydrology.

Atmospheric modelling is a basis for much of the research and operational development in BMRC, and there is continuing work on enhancement of the unified BMRC Atmospheric Model (BAM). A new version, BAM4.0, was released in December 2003 and it included upgrades in the computational efficiency as well as a number of improvements in the physical parameterisations. There has also been progress in the development of diagnostics of cloud and rainfall from the model which are especially useful for verification studies. An important operational diagnostic from the numerical weather prediction suite is a system to analyse and predict stratospheric ozone and UV radiation at the surface. There was a significant upgrade of the system in July 2003.

Downscaling and bias correction of model output are essential elements in the development of robust objective guidance for operational forecasting. Methods involving both model output statistics (MOS) and optimal blending of independent estimates (optimal consensus forecasts) have been developed and are being used routinely in forecast operations.

The 15^th annual BMRC modelling workshop was held in October 2003 on “Current issues in the parameterisation of convection” which remains as an outstanding problem affecting both weather and climate prediction. There were a dozen overseas participants at the workshop, and keynote speakers were Alan Betts, Brian Mapes, Martin Miller, and David Randall.

Air quality analysis and prediction are of growing importance to the Bureau, and the collaboration with CSIRO and the Victoria EPA continues to enhance the real-time air quality prediction system that currently operates over the Sydney and Melbourne regions. The emissions inventory has been greatly improved and the treatment of aerosols has been expanded to include wind-blown dust. The air quality model is complemented by the transport and dispersion model, which is based on HYSPLIT and is used for tactical predictions of smoke and volcanic ash in the Bureau, as well as supporting the international Environmental Emergency Response process.

In collaboration with the Department of Environment and Heritage, a report was published in April 2004 on current and past air quality in major urban airsheds across Australia. The report, which analyses data from 79 sites over the period 1991-2001, provides a benchmark for future national analysis of ambient air quality data collected under the National Environment Protection Measure (NEPM) process.

Ensemble predictions are necessary to provide a measure of the uncertainty associated with predictions of weather and climate. The global ensemble prediction system continues to run routinely, and a LAPS-based system is being developed to include perturbations associated specifically with tropical cyclones. As part of the international activities of the Working Group on Numerical Experimentation (WGNE), a system has been developed to verify the rainfall, temperature and wind predictions of the BMRC ensemble systems.

The generalised multivariate statistical interpolation (GenSI) assimilation system continues to be refined and unified across the global and regional numerical weather prediction (NWP) systems. Satellite data are vital sources of information for NWP systems, and the incorporation of scatterometer-based winds is found to improve both the regional and global systems.

To assist in the design of the next generation of assimilation system, an international workshop was held in November 2003 on ensemble Kalman filter (EKF) methods. The meeting led to a consolidation of plans, and work has commenced on the development of an EKF assimilation system using the basis of the current GenSI system.

A national mesoscale (4-km) surface analysis scheme has been developed to support NWP and nowcasting applications. The scheme is run hourly and uses all available surface data to estimate the distribution of temperature and winds.

International model experiments have provided a mechanism for BMRC models to be improved through the identification of systematic errors by intercomparison with a range of overseas models. Scientists in BMRC have been involved in the design and planning aspects of these studies, as well as in the execution of specific sub-projects. The novel climate feedback analyses developed in BMRC have contributed to the development of the Cloud Feedback Model Intercomparison Project (CFMIP), which will help reduce the uncertainty in climate change projections associated with the representation of cloud processes. Moreover, the BMRC analyses of predictability are being used to clarify the results of model runs in the Climate of the Twentieth Century (C20C) program.

Under the Climate Action Partnership (CAP) between Australia and China coordinated by the Australian Greenhouse Office (AGO), a collaborative project is being established with the China Meteorological Administration to study the Asia-Australia monsoon system. As well as increasing our understanding of a significant aspect of the climate system in our region, the project is aimed at reducing uncertainty in projections of future climate change.

Analysis of large-scale instability of the southern hemisphere circulation before and after the mid-1970s shows significant changes in the strength and location of the mid-latitude storm tracks. The analysed reduction in cyclogenesis near south-western Western Australia is consistent with the observed reduction in rainfall and run-off that occurred around that time. Further modelling studies are being carried out to examine possible causes of the circulation changes. This work contributes to the Indian Ocean Climate Initiative (IOCI), which has been an effective collaboration between BMRC, CSIRO and WA Government agencies. The second stage of IOCI commenced in July 2003 with the BMRC contribution focused on improved understanding of the causes of the decline in rainfall in south-west WA. Downscaling the results of several climate change modelling experiments suggests that the drying trend could continue under continuing greenhouse forcing.

In addition to the focus on WA, a number of other studies of regional climate change and variability have been carried out. One study has found that the decreasing trend in spring snow depth in Australia over the last 40 years is attributable to increasing temperatures rather than any change in precipitation.

Diagnostic studies are facilitated by the software package, Diagnose, which allows Australian climate anomalies to be analysed readily and in essentially real time as climate data are archived at the end of each month. The package has been upgraded to allow calculations of the correlation of anomaly time series with large-scale variables from the NCEP-NCAR reanalysis.

There is a continuing interest in the analysis of climate extremes, and the fifth Asia Pacific Network (APN) workshop on climate extremes was held in BMRC in March 2004. The meeting involved participants from 15 countries, and activities included examination of the links between the observed changes in climate across the region and large-scale features, such as sea-surface temperature.

The Madden-Julian Oscillation (MJO) has a dominant effect on weather in the Australian tropics, and there is continuing research on the role and prediction of its variations. In particular, the relationship between the MJO and the El Nino – Southern Oscillation (ENSO) has been investigated, and it is found that the MJO does tend to reduce the predictability of ENSO. Modelling experiments have also been carried out to clarify the role on the Indian Ocean variability in ENSO.

A new version of the BMRC coupled model is being developed, building on the upgrades to the atmospheric model (BAM4) and the ocean model (Australian Community Ocean Model – AusCOM). The current operational coupled model (POAMA) provides results as good as, if not superior to, other models used for seasonal to inter-annual prediction.

The research field station at Darwin continues to be a focus for research aimed at improving our ability to predict both weather and climate variations in the tropics. Observations from the US Atmospheric Radiation Measurement (ARM) site, associated with the BMRC operations, are being used to evaluate model simulations of tropical storms. Planning has commenced for the execution of the Tropical Warm Pool International Cloud Experiment (TWP-ICE) in early 2006. The TWP-ICE project will involve collaboration with ARM and other national and international research groups, and it aims to focus particularly on the cirrus clouds associated with monsoon storms that have a substantial impact on the radiation balance in the tropics.

The strategic research from the field studies in Darwin has provided the foundation for a range of meteorological applications to support operational weather forecasting. Much of this activity is now incorporated in the Radar Network & Doppler Services Upgrade (RNDSUP) project, implementing the Commonwealth Government initiative in 2003 to modernise the Bureau's radar network. In particular, the 3D-RAPIC radar analysis and the Thunderstorm Interactive Forecast System (TIFS) are being tested for operational use. The TIFS system is being enhanced through links to the National Thunderstorm Guidance System, which uses output from the operational LAPS model to predict areas of severe weather up to 48 hrs ahead. The TIFS system is also being tested in Sydney to provide thunderstorm alerts for aviation operations.

The Bureau continues to support the Cooperative Research Centre (CRC) program, with involvement in the CRC for Catchment Hydrology and the new Antarctic and Bushfire CRCs. There is also cooperation with a range of partners in proposals for three new CRCs covering water, satellite applications and climate risk management. In cooperation with the Bushfire CRC and the World Weather Research Programme (WWRP), an international workshop on fire weather was held in October 2003 in BMRC.

The joint BMRC-CSIRO-RAN Bluelink project was formally launched by the Parliamentary Secretary in October 2003. The project will lead to the development of an operational ocean analysis and prediction system providing real-time products on the state of the ocean up to several days ahead. The project relates closely with the international Global Ocean Data Assimilation Experiment (GODAE), and the international project office for GODAE is located in BMRC.

The Commonwealth Government enhanced and refined the National Research Priorities (NRPs) in 2003, and the refinements included “Responding to climate change and variability” as a priority goal. Under the revised program, nearly half of the research in BMRC, which is primarily focused on fulfilling national needs arising from the Meteorology Act 1955 (Cwth), contributes directly to the NRPs.

Fig.1 Organisational structure of the Bureau of Meteorology