Simulation cyclone Ita in Queensland using Delft3D-FLOW

Published: 11 April 2014

For the cyclone Ita, arriving in Queensland, Deltares made a simulation on April 10, of the effects of the cyclone on the water level. The simulations are run with Delft3D-FLOW. We made a simulation with wind fields based on the Bureau of Meteorology cyclone forecast track of 5 pm April 10th and with a wind field based on the the JTWC cyclone forecast track number 12. These tracks differ, therefore the simulation results give an idea of variability in the results. Furthermore, due the difference in available data with these tracks, the methods used to generate the wind fields differ. In particular, the resulting size of the BoM based cyclone in the wind fields we generated is larger than the size of the JTWC based cyclone. You see the effect of these differences in the resulting water levels.

Check out the simulations:

Waves are not included in these simulations. The animations show the results of the simulations without tides, i.e. simulated surge only. The simulations based on the JTWC cyclone forecast track show that the peak of the surge coincides with low tide. An acceleration or deceleration of the cyclone can change this favourable timing.

Please be aware that these are simulations performed with coarse resolution models (simulation take approx. 5 min on an office PC) based on uncertain tracks and wind forecasts. The results are indicative only and should not be viewed as an accurate description of what will happen. The results were offered to the Bureau of Meteorology in Australia and were well received.