3. Predicting the Likelihood of a Disastrous East Coast Low

CASE STUDY: Responding to a Natural Disaster 3. Predicting the Likelihood of a disastrous “East Coast Low” On the 7th June the Bureau of Meteorology (BOM) released the following Media Alert:

Thursday, 07 June 2007 BOM media release

Severe weather alert for eastern NSW at end of the week

A developing weather system will bring severe weather to eastern NSW - including Sydney - during the next 48 hours…..A low pressure system off the Mid North Coast of NSW is expected to deepen and move southwards….. The low will bring very heavy rain to a wide area leading to possible flooding…..It's too early to predict the precise location of the heaviest rainfall and strongest wind, as this will depend on the eventual position and movement of the centre of the low….

As things turned out, the BOM’s Media Alert predicted quite accurately the weather events that led to the severe flooding of the Central Coast and Hunter River the following weekend.

Ten days later, on the 19 June 2007, ten days, the Bureau issued this further alert:

Tuesday, 19 June 2007 BOM media release

More severe weather on the way…

An intense low is expected to develop rapidly off Sydney overnight Tuesday with southerly winds reaching storm force in NSW south coastal waters Tuesday evening, extending through Sydney and Hunter waters to the Mid North Coast on Wednesday morning….. Damaging winds with gusts to 100km/h are expected along the coastal strip…..This will be the third intense weather system to affect the NSW coast in the past fortnight….

On this occasion, the intense low pressure system detected on the 19 June (see Map 5 on the previous page) moved rapidly away from the coast out to sea (see map 6). Thankfully, the potential damaging winds forecast by the BOM did not eventuate. THE INSTRUMENTS OF THE WEATHER FORECASTER Weather prediction is an “exact science” applied to a highly complex, changeable, natural phenomenon. The latest technology and theoretical models are employed in the continually evolving effort to better forecast the weather events that so affect our daily lives. ACTIVITY: Using secondary sources of information (encyclopaedias, library books, the Internet), construct a Table that records the following devices (Device) used by weather monitors; a brief description of how each one works (How It Works), together with what each one is used to monitor (Use).

Devices: Aneroid barometer; Tipping-bucket Rain-gauge; Weather Watch Radar; Lidar; Geostationary Weather Satellite; Polar-orbit weather Satellite