CASE STUDY: Responding to a Natural Disaster the Worst in Nature - the Best in Us Responding to a Natural Disaster
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CASE STUDY: Responding to a Natural Disaster The Worst in Nature - The Best in Us Responding to a Natural Disaster AAP Breaking News 2007, June 09, 01: 52 am NSW Premier declares natural disaster: NSW Premier Morris Iemma has declared a "natural disaster" for the Hunter and Central Coast regions after severe storms over the past 24 hours caused widespread damage. Mr Iemma said the declaration of a natural disaster area triggered a range of assistance for individual residents, business owners and councils whose properties have been damaged by the strong winds, rain and flooding …… Plate 1: Flash flooding, Newcastle West Plate 2: SES taking people to safety, Plate 3: Flooding of residential areas (ABC, Janek ) Wyong (SES) Chittaway (SES) CENTRAL COAST NSW, JUNE 2007. Where were you on Friday 8th June 2007? Were you caught in the gale force winds and torrential rainfall that struck coastal New South Wales on that Friday afternoon? When did you first become aware that the storm damage and floods were of such intensity that only the formal declaration of a “natural disaster” would be adequate to deal with the consequences of this surprise weather event? CASE STUDY In this Case Study of a Natural Disaster we seek to answer the following questions: How do we as a community research natural disasters? How do we plan for them? How do we respond to them? We will mainly be concerned with analysing the events of June 2007 as an example of a relatively extreme, damaging weather event, related to the mechanisms of the global water cycle, and requiring both immediate short term responses as well as long-term planning. CASE STUDY: Responding to a Natural Disaster 1. Constructing a local Time Line of famous “East Coast Lows” What is an “East Coast Low”? East Coast Lows (ECL) are intense low-pressure weather systems which occur on average several times each year off the eastern coast of Australia, in particular southern Queensland, NSW and eastern Victoria. Gales and heavy rain occur on and near the coast south of the low centre, while to the north of the low there can be clear skies. ECLs will often intensify rapidly overnight making them one of the more dangerous weather systems to affect the NSW coast. The challenge for weather forecasters is to accurately predict the location and movement of the centre of the low. Source: Bureau of Meteorology ACTIVITY: The Table below carries a list of dates in the left hand column and in the right hand column a scrambled set of images and/or descriptions of recent infamous historical events associated with weather events known as “East Coast Lows”. Try to match the events to the listed dates. (You may choose to use the template in Appendix 1, and paste photocopies of the events in the appropriate blank cells of the Table.) Date Scrambled historical events associated with East Coast Lows August The "Sygna" storm: the wreck of the Sygna, driven onshore 1857 during the storm, still lies on Stockton Beach, near Newcastle. May The Hunter River floods: Maitland Railway Station in the floods 1898 from which about 15,000 people had to be evacuated. April The Georges River floods: wind reached 40 knots at Norah 1927 Head, and Observatory Hill in Sydney had its highest daily rainfall total on record - 328mm. February The "Dunbar" storm: James Johnson was sole survivor of the 1955 Dunbar, a sailing ship carrying 122 people, wrecked off South Head while trying to seek shelter in Sydney Harbour. May The “Pasha Bulker” storm: aground on Nobbys Beach, 1974 Newcastle. August The “Maitland” storm: the site where the wreck of the steamer 1986 Maitland finally came to rest after it ran into a major storm north of Sydney, with the loss of 24 lives. June The Wyong River flood: the waters poured over the railway line 2007 between Wyong and Tuggerah. TESTABLE HYPOTHESIS: “East Coast Lows” of significant magnitude to cause “Natural Disasters” on the Central Coast of NSW occur mainly in the months from May to August. OPEN-ENDED QUESTION: Think about what sources of evidence there might be concerning major East Coast Low events in pre-European times. Suggest some possible methods for researching local weather conditions over say the last 2000 years that might be used to test this hypothesis and discuss the likely effectiveness of such methods. CASE STUDY: Responding to a Natural Disaster 2. Tracking the Intensity and Movement of ‘East Coast Lows’ ACTIVITY: Examine the following weather maps produced by the Bureau of Meteorology for selected days and times in June 2007: Mean Sea Level Atmospheric Pressure (MSLP, hPa) isobars for Australian Region, June 2007 Figure 1: 10 am, Wed 06 June 2007 Figure 2: 4 am, Fri 08 June 2007 Figure 3: 10 am, Sun 10 June 2007 Figure 4: 10 am, Mon 18 June 2007 Figure 5: 10 pm, Tue 19 June 2007 Figure 6: 4 pm, Wed 20 June 2007 Based on your understanding of weather maps of this kind, answer the following questions for the days in June listed in the above maps: 1. On which days, would you have expected the weather on the Central Coast of NSW to be relatively fine?...................................... 2. On which of these days might you have expected bad weather?....................... 3. Is there any particular day when you might have expected very severe storm conditions on the Central Coast of NSW? ……………………… Why? CASE STUDY: Responding to a Natural Disaster 3. Predicting the Likelihood of a disastrous “East Coast Low” On the 7 th 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 CASE STUDY: Responding to a Natural Disaster 4. The Difference between Weather and Climate The details of our day-to-day experience of the weather are quickly forgotten as we go about the business of our lives. On the other hand, Meteorologists (those scientists who study the weather) make it their responsibility to maintain a long-term memory of these details. The daily weather data that they collect from a wide geographic area and from a wide variety of sources is recorded and stored systematically (in computer data bases) year after year. The reason meteorologists do this, is that when such data is processed to give a long-term history of the weather , it reveals patterns and trends which can be vitally important in assisting the weather forecaster to improve the reliability of predictions made about future weather events. This helps us to plan for the events. Definitions: “Climate” and “Weather“ Climate is the sum or synthesis of all the weather recorded over a long period of time. It tells us the average or most common conditions, or extremes, or counts of events, or frequencies. Weather is a description of conditions over a short period of time - a "snap shot" of the atmosphere at a particular time. Source: Bureau of Meteorology ACTIVITY: Consider these two “tags” used by the Bureau of Meteorology to describe the difference between weather and climate : Climate is what you expect; Weather is what you get. If weather is the watch then climate is the calendar. Now see if you can come up with a memorable “jingle”, “short poem”, “song” or “cartoon” that illustrates the difference between the concepts of weather and climate. OPEN-ENDED QUESTION: The series of weather maps which you looked at before, on Page 3, were selected from a long sequence of weather maps published by the Bureau of Meteorology.