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| Prediction Research |
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| Meteorologists in the Prediction Research section of SAWS are involved in various research projects, many of which are in collaboration with other academic and research institutes both locally and internationally. These projects currently focus on mainly four areas (programmes): |
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| Long-Range Forecast Systems |
The South African Weather Service has been issuing long-range forecasts since June 1994. These forecasts are a result of SAWS expert interpretation and combination of forecasts produced by a variety of forecast models, both statistical and dynamical, run at international and national forecast centres. Consensus probability forecast maps of temperature and rainfall are subsequently produced every month, but ongoing research is necessary to better the forecasts and methods. Also, tailor-made products are designed to fit the needs of various end users. The main objectives of this programme are:
- To actively develop and improve long-range forecasting techniques.
- To run regional and global long-range forecast models and
produce skilful operational long-range temperature and
rainfall forecasts for southern Africa.
- To compile archived hindcasts from regional and global
long-range forecast models and to apply standard verification
systems to these and operational long-range forecasts
- To investigate intra-seasonal relationships and derive
products to aid in forecast purposes.
- To produce skilful tailor-made forecasts for specific
end-users and assess the economic value of forecasts on all
forecast time scales.
- To actively pursue outreach activities to commercial
clients and disadvantaged communities and assess the impact of
weather and climate variability on society.
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| Short-Range Forecast Systems |
Weather service providers worldwide use objective forecast guidance in conjunction with human forecasters to produce their forecasts. The objective forecast guidance is generated through numerical weather prediction models. At SAWS we run the regional Eta and finer-scale MM5 mesoscale models operationally. These systems are not static but need continued upgrading and improvement to remain competitive relative to the available global models. The provision of global model products, even if they are obtained from external sources, needs to be maintained and improved. Furthermore, forecasters need to be trained in the use of these various numerical model products, for example the 14-day ensemble product. The main objectives of this programme are to:
- Provide the SAWS forecasting offices with reliable forecast guidance based upon the best available technology both locally and elsewhere.
- Contribute to the understanding of the use of forecasting
tools through sensitivity studies.
- Provide model output to clients.
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| Forecast Methodology |
The aim of this project is to aid in the forecasting techniques for in the time period from 0-72 hours up to day 14. The vision is to improve on the science behind decision making processes and thus enhance the quality of the forecasts issued for these mentioned time periods. The main objectives of this programme are to:
- Provide the SAWS forecasting offices with the best forecasting methodology from nowcasting (<2 hours) to short range (up to 72 hours) by:
- The use, manipulation and interpretation of all available
data, model systems and tools;
- Developing and/or introducing new forecasting techniques,
tools and methodology;
- Transfer of knowledge to forecasters through
collaborative case studies, presentations and training
sessions.
- Enhance and transfer knowledge on methodology to use tools
and systems for medium-range weather forecasting (days 3 to
14).
- Use and improve verification systems of operational
weather forecasts and nowcasts to address problem areas in
forecasting methodology.
- Enhance forecasting quality, norms and standards by
monitoring and improving forecasting practices.
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| Verification and Assesment |
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Forecast verification is the process of
determining the quality of forecasts. Various procedures exist
but all involve measures of the relationship between a forecast
and corresponding observations. Verification results are input
for administrative, scientific and economic decision-making.
The SAWS currently only performs scientific evaluation of some
of the forecast products but a great need exist to perform a
more comprehensive evaluation of all forecast products, which
must be done in a coherent fashion such that the
administrative, scientific and economic needs are met. To
address this shortcoming, a verification project has been
initiated with its main objectives to:
- Develop a comprehensive forecast verification system that meets WMO standards.
- Create pathways for feedback of the verification results
to the scientists, forecasters and managers.
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| Bethlehem Precipitation Research Project |
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| SIMAR Project |
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| Safari 2000 |
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