The Bureau of Meteorology’s (BoM) Victorian director, Dr Andrew Tupper, has acknowledged improvements could be made in the messages it put out, after predicted heavy rainfall over much of the state failed to occur.
Farmers across the state raced to complete harvesting or moved stock to higher ground, after the bureau issued the warnings of falls of up to 200 millimetres of rain, late last week. Dr Tupper said the bureau would “look at the language of this event, when we get a bit of time to breath.”
He said the bureau communicated in a number of ways, from the “vanilla” wording of possible rainfall, to the stronger language of severe weather warnings and flood watches. “We need to make sure that the specialist populations - such as farmers - are all getting a consistent message,” Dr Tupper said. “I am sure there are improvements that can be made.”
But he said much of the feedback was positive, as people were able to plan for the predicted weather event. “With this one, we saw there was a very clear potential of a very severe event, that’s why we went hard. We know we have to get the message out there, as early as we possibly can, to help with preparations.”
Dr Tupper said the bureau was part of a world-wide trend towards what was called “ensemble modelling”. “It’s a technique where you look to the best possible modelling of what will happen, but then you change some of the initial parameters – it’s like you flap a lot of butterfly wings to create a bit more chaos. You see how much that might change the forecasts, if something shifts slightly. If all the models continue to move in the same direction, you know it’s a highly predictable event and you can give a lot of confidence, in rainfall events.”
If the models did not line up, the bureau could advise its predictions came with a huge range of probabilities.
It’s like you flap a lot of butterfly wings to create a bit more chaos. You see how much that might change the forecasts, if something shifts slightly.
- Dr Andrew Tupper, Bureau of Meteorology state director.