Contents AMOS Bulletin Volume 23 Number 5
Presidentâ€™s Column News
News from the Centres Conference Announcements Articles D.Greenslade, M.Hemer, G.Symonds and P.Craigâ€“ Wind waves research in Australia Meet a Member Significant Mesoscale Oceanography
97 102 103 108 109
Snapshot Significant Weather
Charts from the Past Calendar
Cover picture: Beaumaris Bay, August 2010. The view from a kayak looking west towards the You Yangs (over 50kms away). Sunshine is making its way through the stratus deck and reflected evocatively in the calm water below. For information on less calm waters, check out the article in this issue on wave research in Australia Image: AMOS member Mark Collier. (Image and description reproduced with permission from Mark Collier). Unless specifically stated to the contrary, views expressed in the Bulletin are the personal views of the authors, and do not represent the views of the Society or any other organisation or institution to which the author(s) may be affiliated. Printed on 100% recycled paper
Editorial The September floods in Victoria have reminded us once more of the tumultuous nature of Australian weather. I still remember the last time Victoria was inundated to such an extent, when I was a child living in the Goulburn Valley in 1993. Our front yard became a swimming pool! Blair Trewin’s very appropriate Chart from the Past in this issue has a more scientific account of that period. The warnings and preparations from both the Bureau of Meteorology and Emergency Services to protect communities from the recent deluge should be commended. People were aware that the rain was coming, when the rivers would peak and where, and acted accordingly. This is in stark contrast to the early settlers of Australia, who took decades to come to terms with the fact that this country is one of climatic variability. The first European inhabitants of the Hawkesbury region in New South Wales, for example, took over 10 years and more than seven floods to realise that the low-lying areas around the river were not appropriate for habitation (C. Fenby, personal communication). I sometimes wonder whether we remain a bit stubborn in that respect,
determined to live in all of Australia’s natural beauty, despite the unforgiving climate. As the time rolls on, we are becoming better at predicting these kinds of potentially devastating events, and, in my opinion, communicating the science of them as well. The attendance at last month’s climate change communication workshop held by the Melbourne Centre highlighted the enthusiasm of AMOS members to embrace this increasingly important role of the modern scientist. This enthusiasm is also extending to online communication. AMOS’s new Facebook and Twitter webpages means that members can communicate with each other and with the public easily, and keep up to date with relevant news from all over the world, as well as warnings if needed. Stewart Allen and Ailie Gallant have done a wonderful job in giving AMOS this online presence, and the best way to thank them for their efforts is to sign up, log on, and join the conversation. Linden Ashcroft
President’s Column Was Black Saturday unprecedented? In their final report on the bushfires of 7 February 2009, the 2009 Victorian Bushfires Royal Commission determined “…neither the day nor the fires to have been unprecedented”, even though the terms “unprecedented” and “without historical precedent” appear frequently in the submissions provided to the Royal Commission. I was surprised by the Royal Commission’s conclusion, and thought I should try to understand how they reached it. The New Shorter Oxford Dictionary (1993) defines “unprecedented” as “Having no precedent, unparalleled; that has not previously occurred.” There were certainly several aspects of the climate leading up to Black Saturday, and the weather on that day that had not previously been observed since the start of instrumental observations in Melbourne in the mid-19th century. These include: • The Melbourne region had 12 years of below average rainfall leading up to the start of 2009. The previous longest period of below average rainfall was six years. Then in the five
weeks immediately preceding Black Saturday, Melbourne received less than 1mm rainfall. • Melbourne saw its worst heatwave on record a week prior to Black Saturday – temperatures above 42˚C had never been exceeded on three days in a row, but at the end of January 2009 three days in a row exceeded 43˚C. • Black Saturday broke the record for Melbourne’s highest maximum temperature and exceeded the February record by more than 3˚C. All of the conditions above were unprecedented, in the sense of “not previously occurred” (at least since the start of instrumental records in Melbourne in the mid19th century). They would all have contributed to increasing the fire risk, largely through increasing fuel drying. Black Saturday also saw very strong winds and extremely low humidity.
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Not surprisingly, these extreme weather conditions before Black Saturday, and on the day itself, led to values of the Forest Fire Danger Index (FFDI) not previously recorded in the Melbourne region. The following list of FFDI values for major Victorian fires comes from a report by Dr Kevin Tolhurst prepared for the Royal Commission. The FFDI for major Victorian fire days Date FFDI 7 February 2009 172 16 February 1983 120 13 January 1939 100 8 January 1969 97 14 January 1944 77 14 February 1926 70 Jan/Feb 2003 63 A quantitative analysis leaves no doubt that the combination of weather conditions leading up to Black Saturday, and on the day, had not been observed previously, in the 150 years of Melbourne instrumental weather data, and that the combination of these weather conditions led to an extraordinary threat of catastrophic fire as measured by the FFDI. So, how did the Royal Commission reach the conclusion that the day was not unprecedented? They asked a panel of six distinguished experts in land and fuel management during oral testimony whether they agreed that the day or the fires were “unprecedented”. Some of the experts acknowledged that the weather conditions had not previously been equalled, although none agreed with the proposition that the fires themselves were unprecedented. There does not appear to have been any quantitative examination of the question, nor any written follow-up to the oral responses from the expert panel. The written testimonies from the experts do not address this question. From my reading of the transcripts of the Commission’s proceedings, both the experts and the Commission appear to be pointing out that catastrophic fires have occurred in the past in Victoria in association with hot, dry, windy conditions. So although Black Saturday was catastrophic, it did not represent, in the words of the Commission, “a shift change that sets them apart from what Victoria has experienced from time to time in the past.” The Commission and the experts appear to rely on the first definition of “unprecedented” I quoted from the Oxford Dictionary earlier, i.e. “having no precedent, unparalleled”, and are suggesting that previous fires occurring in hot, dry, windy conditions did provide a precedent
(even if the meteorological conditions on those earlier occasions were less extreme). On the other hand, others who provided submissions to the Royal Commission (including myself) used the term “unprecedented” in the sense of “has not previously occurred”. Even if we agree with the definition the Commission appears to have adopted, “having no precedent”, it seems difficult to conclude from the above list of FFDI values that Black Saturday did not represent a “shift change”. The FFDI values for Black Saturday were much more extreme than were those of Ash Wednesday (which in turn were substantially above those of 13 January 1939). However, putting aside the question of whether Black Saturday represented a “shift change”, we still are left with the question of which of the two definitions of “unprecedented” – either “having no precedent” or “not previously occurred” – is the more useful. I think a focus on the fact that we had not previously seen such extreme fire weather and climate conditions is important. Such a focus can alert planners and politicians to the possibility that even worse conditions might be possible, and that we cannot only rely on historical climate and weather conditions, in our planning for dealing with bushfires. If we simply note that Black Saturday was just another instance of serious fires occurring in association with hot, dry, windy conditions, then we could lose sight of how extraordinary the weather conditions were, and we may not consider changes in strategy that could help us cope with even more extreme fires in the future. More specifically for AMOS, the ability of the Bureau of Meteorology to issue accurate forecasts of the unprecedented conditions of Black Saturday was crucial in reducing the impacts of the disaster. Imagine the damage that would have resulted if the abilities of the Bureau in 2009 to monitor and predict were no better than those possible at the time of the 1939 fires, or even in 1983. The AMOS submission to the Royal Commission pointed out that the Bureau of Meteorology had done an excellent job in predicting these extreme conditions. Meteorology needs to continue to work on improving forecasting, taking into account that past climate and weather may no longer be the only, or even the best, guide to the future. Declaration of interest: The author was employed by the Bureau of Meteorology from 1970 to 2005, and completed the Bureau’s meteorologist course in 1971.
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News AMOS joins the online community Stewart Allen AMOS National Council In order to improve value for members and increase our exposure to the public, AMOS has decided to make use of the popular social networking websites Twitter and Facebook. Other societies and institutions, both local and abroad, are already taking advantage of these websites. AMOS has now decided to use them as well, as they provide a convenient way to communicate with our members and promote our sciences to the broader community Twitter is a popular social networking website that allows users to publish short (140 character) messages. Links can be included in the message to interesting articles, photos and other Twitter users. The ease by which networks can be formed with related societies and institutions around the world means that news and information of relevance to AMOS members can be disseminated easily and quickly. Anyone can visit the AMOS Twitter page via the link below, even without being a Twitter user. Similar to Twitter, Facebook is a social networking website that allows users to be members or â€˜fansâ€™ of a group, organisation or society. However, Facebook provides additional features such as integrated photo publishing, discussion pages and events to which members can RSVP. Facebook is
enormously popular and is the second most popular website in the world after Google. After being active on Twitter and Facebook for only one month, AMOS has built a significant following on both websites and we hope this community continues to grow. Social networking makes for an informal environment, where the members and followers can interact and the AMOS community can grow. To give new users a head start in the world of Twitter and Facebook, and to explain the sometimes mystifying jargon of these services, a brief guide has been written for AMOS members and is now available on the AMOS website (link below). If you are interested in making use of these online services, please read the guide and visit the AMOS Twitter and Facebook pages. Perhaps you may even consider using these services to share something of interest with the online AMOS communities. Further information: twitter.com/AMOSupdates www.facebook.com/pages/AMOS/14580 1572105950 www.amos.org.au/news/id/93
AMOS members well represented in the next IPCC report Eleven AMOS members have been selected as lead authors or editors for the next Intergovernmental Panel on Climate Change (IPCC) report. The AMOS members are part of a team of 831 international experts, including around 35 Australians. They will volunteer their time over the next four years to synthesise research on climate change from all over the world for the Fifth Assessment Report (AR5), due to be published between 2013 and 2014. Nine AMOS members are involved in Working Group I, which looks at the physical basis of climate change, while two others are a part of Working Group II that examines impacts and adaptation.
The IPCC received approximately 3000 nominations for authors, 50% more than for the Fourth Assessment Report, which was released in 2007. To be selected as a Coordinating Lead Author, Lead Author or Review Editor is an honour to represent the international scientific community. It is also recognition of expertise in the field. In the selection of authors, particular attention has been given to relevant knowledge. This ensures that IPCC author teams consist of leading experts in the respective fields with a range of scientific views on climate change. Those selected come from fields including meteorology, physics, oceanography, statistics, engineering, ecology, social sciences and economics.
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Regional and gender balance was considered in the selection process, as was the involvement of new and younger scientists. To bring in new ideas and perspectives, over 60% of the selected authors have not been involved in the IPCC process before. 25% of the authors for the AR5 are female, a significant increase from the previous report. Around 30% of selected authors come from developing or economically transitioning countries. This increase highlights the focus of improved regional coverage in the next report.
The aim of the AR5 is to genuinely bring together the current state of knowledge in a product of unparalleled influence. The next meeting of Working Group I, which involves the most AMOS members, takes place at the start of November in China. Further information: www.ipcc.ch
Wettest September on record as La Niña sets in Australia has recorded its wettest September on record, and seasonal outlooks predict above average rainfall for much of the country in the coming months as La Niña conditions persist. National rainfall in the first month of spring was nearly three times the long term average, much greater than the previous record set in 1906. Most of this was associated with rainfall in the tropical and subtropical regions, with over a quarter of the Northern Territory breaking records for the highest September rainfall. South Australia has already received more than its annual average rainfall, while Victoria has received just over 80%. The Bureau of Meteorology’s latest Seasonal Outlook has predicted that these wetter conditions may continue. Warmer than normal sea surface temperatures in the Pacific Ocean and the eastern Indian Ocean promote wetter than average conditions for much of the country. These positive anomalies are associated with the current La Niña event, which began in early winter this year. The La Niña conditions look set to continue, with the Bureau of Meteorology predicting that warmer than average sea surface temperatures in the Coral Sea, and colder than average central Pacific Ocean temperatures will remain present until at least early 2011.
Niña events, is currently in the top 5% of observed values, suggesting that this particular event could be strong. The monthly SOI value for September was +25. This is the highest monthly value since 1973, and the highest recorded September value since 1917. An increased tropical cyclone season is also predicted by the seasonal outlook, and warmer days and nights for the tropics and southeastern part of Australia. Cooler days are however more likely in the east, particularly southern Queensland and northern New South Wales. Despite the recent rains, most of Australia is yet to recover from the 14 year extended dry period. A special climate statement released by the Bureau of Meteorology showed that most of southern Australia is still experiencing a nine-year drought, while southwest Western Australia, large parts of Victoria and almost half of Tasmania have received their lowest 14 years of rainfall on record since 1996. Further information: www.bom.gov.au/announcements/medi a_releases/nsw/20101005.shtml www.bom.gov.au/climate/current/speci al-statements.shtml www.bom.gov.au/climate/enso/
The Southern Oscillation Index (SOI), which is an atmospheric indicator of El Niño and La
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Merchants of Doubt book launch Presented by the Monash Sustainability Institute and the Melbourne Sustainable Society Institute The Monash Sustainability Institute and the Melbourne Sustainable Society Institute present Naomi Oreskes, co-author of the book, Merchants of Doubt (2010). Date: Wednesday 17 November 2010 Time: 5.45pm book sales; 6.00pm speaking about the book; 7.00pm book signing/sales Venue: Experimedia at The State Library of Victoria 328 Swanston Street, Melbourne In Merchants of Doubt, Naomi Oreskes and Erik M. Conway roll back the rug on this dark corner of the American scientific community, showing how ideology and corporate interests, aided by a too-compliant media, have skewed public understanding of some of the most pressing issues of our era. The book tells the story of how a loose-knit group of high-level scientists and scientific advisers, with deep connections in politics and industry, ran effective campaigns to mislead the public and deny well-established scientific knowledge over four decades. Remarkably, the same individuals surface repeatedly – some of the same figures who have claimed that the science of global warming is “not settled” denied the truth of studies linking smoking to lung cancer, coal smoke to acid rain, and CFCs to the ozone hole. “Doubt is our product”, wrote one tobacco executive. These “experts” supplied it. “Naomi Oreskes and Erik Conway have demonstrated what many of us had long suspected: that the ‘debate’ over the climate crisis – and many other environmental issues – was manufactured by the same people who brought you ‘safe’ cigarettes. Anyone concerned about the state of democracy in
Merchant of Doubt book cover America should read this book.” – Former US Vice President Al Gore, author of An Inconvenient Truth. Naomi Oreskes (PhD, Stanford, 1990) is Professor of History and Science Studies at the University of California, San Diego. Her research focuses on the historical development of scientific knowledge, methods, and practices in the earth and environmental sciences, and on understanding scientific consensus and dissent. She is also the Provost of the Sixth College, UCSD. Free event, no booking required. For enquiries: email@example.com
New report highlights two-way link between ozone layer and climate change Press release from the United Nations Environment Programme International efforts to protect the ozone layer – the shield that protects life on Earth from harmful levels of ultraviolet rays – are a success and have stopped additional ozone losses and contributed to mitigating the greenhouse effect, according to a new report. The executive summary of the Scientific Assessment of Ozone Depletion 2010 provides new information about the effects of climate change on the ozone layer, as well as the
impact of ozone changes on the Earth's climate. The report was written and reviewed by some 300 scientists and launched on the UN International Day for the Preservation of the Ozone Layer, 16 September 2010, marking the 27th anniversary of the signing of the Montreal Protocol. It is the first comprehensive update in four years.
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The report reaffirms that the Montreal Protocol is working. “It has protected the stratospheric ozone layer from much higher levels of depletion by phasing out production and consumption of ozone depleting substances.” Given that many substances that deplete the ozone layer are also potent greenhouse gases, the report says that the Montreal Protocol has “provided substantial co-benefits by reducing climate change.” In 2010, the reduction of ozone depleting substances as a result of the Montreal Protocol, expressed in CO2equivalent emissions (about 10 Gigatonnes per year), were five times larger than those targeted by the first commitment period (2008-
2012) of the Kyoto Protocol, the greenhouse emissions reduction treaty. The report published by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) says that an important remaining scientific challenge is to project future ozone abundance based on an understanding of the complex linkages between ozone and climate change. Changes in climate are expected to have an increasing influence on stratospheric ozone in the coming decades, it says. “These changes derive principally from the emissions of long-
Global emissions of ozone depleting substances (ODSs: CFCs, halons, HCFCs, and others) and their non-ozone depleting substitutes (HFCs) from 1950 to 2050. The blue hatched regions indicate the emissions that would have occurred, in the absence of the Montreal Protocol, with 2– 3% annual production increases in all ODSs. Top: Global ODP (ozone depletion potential)–weighted emissions expressed as Megatonnes of CFC-11-equivalent per year. The dashed line marks 1987, the year of the Montreal Protocol signing. Bottom: Global GWP (global warming potential)-weighted emissions expressed as Gigatonnes of CO2-equivalent per year. Shown for reference are emissions for the range of CO2 scenarios from the IPCC Special Report on Emission Scenarios (SRES). The dashed line marks 2010, the middle year of the first commitment period of the Kyoto Protocol. Also shown is the magnitude of the reduction target of the first commitment period of the Kyoto Protocol, which is based on a 1990–2010 projection of global greenhouse gas emission increases and the reduction target for participating countries. From Figure ES-1, Executive Summary, Scientific Assessment of Ozone Depletion: 2010. Bulletin of the Australian Meteorological and Oceanographic Society Vol. 23 page 94
lived greenhouse gases, mainly carbon dioxide, associated with human activities.” The key findings on the ozone layer from the Scientific Assessment of Ozone Depletion 2010 are: • Over the past decade, global ozone and ozone in the Arctic and Antarctic regions is no longer decreasing but is not yet increasing. • As a result of the phase-out of ozone depleting substances under the Montreal Protocol, the ozone layer outside the polar regions is projected to recover to its pre-1980 levels some time before the middle of this century. The recovery might be accelerated by greenhouse gas-induced cooling of the upper stratosphere. • In contrast, the springtime ozone hole over the Antarctic is expected to recover much later. • The impact of the Antarctic ozone hole on surface climate is becoming evident, leading to important changes in surface temperature and wind patterns.
• It is reaffirmed that at mid-latitudes, surface UV radiation has been about constant over the last decade. • In Antarctica, high UV levels continue to be seen when the springtime ozone hole is large. Many ozone depleting chemicals, such as CFCs (chlorofluorocarbons), once present in products such as refrigerators and spray cans, have been phased out. Demand for replacement substances called HCFCs (hydrochlorofluorocarbons) and HFCs (hydrofluorocarbons) has increased. Many of these are powerful greenhouse gases. Further information: ozone.unep.org/Assessment_Panels/ SAP www.antarctica.ac.uk/met/jds/ozone/ index.html Note: The latest data on ozone levels indicate that the size of the 2010 hole is much smaller than the average size for the last decade. See the links above for more details. –Ed.
Fire and rain: the summer that eclipsed the bounds of extreme weather in the northern hemisphere Ailie Gallant1 and Blair Trewin2 1 2
School of Earth Sciences, University of Melbourne
National Climate Centre, Bureau of Meteorology, Melbourne
Address for correspondence: firstname.lastname@example.org For a significant portion of the Eurasian continent, the boreal summer of 2010 has redefined the boundaries of what we call “extreme” and is now etched in the record books. High temperatures in Russia and torrential rain in Pakistan resulted in catastrophic natural disasters for both countries. Casualties are in the tens of thousands, tens of millions of people have been directly affected by the event, public and private infrastructure has been destroyed and there have been huge economic losses. The heat in Russia has also eclipsed many previous records. Though at first glance these events seem unconnected due to the distance between the two nations, they were, in fact, linked by one persistent atmospheric state that sat stubbornly over Eurasia for over two months. Northeastern Europe and Russia: From the freezer to the furnace In the 9 months from December 2009 to August 2010, northeastern Europe, including western Russian and surrounding countries,
experienced some of the largest climate variations in its recorded history. During a strong positive phase of the North Atlantic Oscillation (a pattern of surface pressure variation between a semipermanent low over Iceland and a persistent high off the Portuguese coast), the region experienced monthly mean temperatures 3–5°C below the long-term average in January 2010. Temperatures remained near or below average until April, before swinging into positive territory through May and June. Precipitation nosedived around the same time, culminating in what Russian authorities were dubbing the worst drought for western Russia since 1972. April-July rainfall was widely 50% or more below normal. As the boreal summer moved into July (the hottest month climatologically), the situation intensified. The mercury continued rising and records began tumbling. From mid-June, warm conditions prevailed as an intense high-pressure system established itself across northeast Europe. As the summer progressed, this blocking high remained
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stationary over a region roughly the size of Western Australia, centred on western Russia. Cold fronts and rain-bearing systems were diverted northward and the region experienced persistent warm and dry winds from the south. Across the region, the average July temperature was approximately 7–8°C above normal, with individual days setting multiple records for extreme heat in late July and early August. Mean daily maximum temperatures for July were nearly 10°C above average in many locations, with several meteorological stations around Moscow reaching above 40°C and exceeding previous temperature records. At Moscow Observatory, a run of 33 consecutive days above 30°C began on 14 July, including separate lots of eight and six consecutive days above 35°C. The previous record of 36.8°C, set in August 1920, was broken six times, peaking at 38.2°C on 29 July. Nights were also exceptionally warm, with 22 out of 26 nights in the period between 14 July and 10 August not falling below 20°C. To place this in perspective, the average maximum temperature in Moscow during July is 24°C, and in 2009 there was not a single day above 30°C, or a night above 20°C. Such records have culminated in what is now touted as a “one in 1000 year” event. Though most intense in western Russia, surrounding countries, including Finland, Estonia, Latvia, Lithuania, Belarus and Ukraine, also experienced extreme and prolonged heatwave conditions. Further west into central Europe, extreme heat occurred in mid-July before easing from late July onwards. National records were set in four countries: Russia (44.0°C), Ukraine (41.3°C), Belarus (38.9°C) and Finland (37.2°C), whilst 39°C was reached locally in the Berlin area, approaching the German record of 40.9°C. Not to be regarded as anything less than exceptional, the heatwave ended with style when a vigorous cold front moved across the region from the northwest on the 19th and 20th of August. Temperatures plummeted into the teens and strong winds and heavy rain caused much damage, particularly around St. Petersburg. The heatwave and drought contributed to an outbreak of forest and peat fires that remained out of control for the duration of the event. The combination of the severe heat, forest fires and subsequent pollution had a disastrous impact on human health, with the Moscow registry office reporting an additional 330 deaths per day in Moscow alone at the peak of the heatwave. The death toll has been put at
around 15,000, but may be much higher. There have been between 50 and 60 reported deaths from the forest fires in Russia and reports of over 1600 drownings of people attempting to cool off in the blistering conditions. In addition, the fires and drought reduced Russia’s grain crop by approximately 40%, leading to a sharp increase in global wheat prices. Pakistan: Opening the floodgates The build-up to the Pakistani wet season was fairly typical, though a stronger than normal monsoon was considered likely given the development of a La Niña in the Pacific and warmer than normal sea surface temperatures in the Arabian Sea and northern Indian Ocean. However, as the end of July approached, it was clear that this wet season was going to be one for the record books. Torrential rains began to impact Pakistan during the last week of July, with the northwest of the country bearing the brunt. In Peshawar, near the border shared with Afghanistan, 274 mm (about 75% of the annual mean) fell on 29 July, and nine of Pakistan’s 39 internationally-reporting stations recorded at least 100 mm on one or both of 28 or 29 July. Whilst such daily totals are not unknown in Pakistan during the summer monsoon, the wide area of heavy rains, and their location in the upper Indus catchment, was optimal to produce severe flooding. As the rains continued, rivers rose and broke their banks readily, with the resulting floodwaters travelling south, flooding much of the Indus valley, before finally making their way to the Arabian Sea at the end of August. Though August was much wetter than normal in much of lowland Pakistan most of the flooding resulted from the late July rains making their way downstream. The result was the worst flooding in Pakistan since 1929, according to the Pakistani government. Some stated that the floods were exacerbated by extensive land clearing in river valleys in recent years. Though most acutely felt in Pakistan, the enhanced Asian monsoon also led to severe flooding in parts of far western China and eastern Afghanistan. In most of India however, except the far north-west, monsoon season rainfall was fairly close to normal. Although heavy monsoon rains were partially blamed on the La Niña and warm Indian Ocean temperatures, the main culprit behind the heaviest rains was the atypical appearance of mid-latitude low-pressure systems moving in from the north. The resulting strong convergence combined with tropical moisture
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to enhance the monsoon and cause the heaviest seasonal rains in decades. In response to a tour of the afflicted areas, UN President Ban Ki-moon stated “The magnitude of the problem; the world has never seen such a disaster. It’s much beyond anybody's imagination”. Indeed recent estimates of the number of Pakistani people directly affected by the flood, either through loss of property or possessions, injury and death, now exceed 20 million. Media outlets have reported that the number of people affected now exceeds the total of the Indian Ocean tsunami, the 2005 Kashmir earthquake and the 2010 Haiti earthquake combined. Estimates of the death toll as a direct result of the flooding exceed 2000. However, many more continue to be at risk from poor water quality and tens of thousands have been treated for illnesses such as dysentery and malaria since the floodwaters have receded. In Islamabad, 152 people were killed in a plane crash on the 28th July that was blamed on the severe weather that caused the flooding. Further reports describe the flooding of 17 million acres of agricultural land and over 200,000 animals killed. The common link Despite the distance between western Russia and Pakistan, these two events were linked by a persistent state of the upper atmosphere that was established in late June and remained in place for almost two months. The protagonist was a highly anomalous state of the polar jetstream (a region of strong, upper level winds at a height of around 10km – 12km above the surface). Typically, the polar jetstream weakens during the boreal summer and remains relatively east-west oriented, steering rain-bearing weather systems across the northern hemisphere mid-latitudes. However, during July and August 2010, the polar jet
intensified over northern Scandinavia, with average windspeeds around three times greater than normal. This effectively created a giant wall between the cooler, higher latitudes of the Arctic and warmer middle and lower latitudes. The typical rain-bearing systems were diverted north of Europe, much further north than normal. Upper level convergence in the right exit region of the jet streak (or area of maximum upper-level winds) caused divergence at the lower levels, leading to a high-pressure system at the surface over west Russia. This pattern was reinforced for the next two months, leading to a blocking high at the surface and persistent dry and hot southerly winds from the subtropics. These winds penetrated into western Russia, resulting in the persistent heatwave and drought described earlier. Interestingly, not only was this polar jetstream much stronger than normal, it also diverted from its usual east-west path across central Russia and instead curved south through central Asia. As such, the rain-bearing lowpressure systems following the upper atmosphere “steering” winds moved south through central Asia and straight into Pakistan. Converging air in the mid-latitude systems from the north combined with tropical moisture from the Asian monsoon, with the result being torrential rains and subsequent flooding over Pakistan and one of the worst natural disasters in recent memory. Further information: www.esrl.noaa.gov/psd/csi/ moscow2010/ www.wunderground.com/blog/ JeffMasters/comment.html? entrynum=1576 www.ncdc.noaa.gov/sotc/? report=hazards&year=2010&month=7
News from the Centres Melbourne Climate Science Communication Workshop Damien Irving AMOS Melbourne Centre On the topic of anthropogenic climate change, the disparity between scientific understanding and public opinion is a constant source of frustration for those working in the field. While there is an obvious need to improve the communication of climate science to the general public and key stakeholders, it is often
difficult to determine exactly what should be done in order to achieve this improvement. Recognising this as a key area of concern, the AMOS Melbourne Centre convened a half day workshop on climate science communication on Friday, September 24th. The workshop was hosted at the University of Melbourne and
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aimed to bring together people involved in both the science and communications fields, to identify key issues in effectively communicating with different audiences. Testament to the high interest in this issue, over 130 delegates attended the workshop. As expected, CSIRO, the Bureau of Meteorology, Monash University and the University of Melbourne were well represented. The AMOS Melbourne Centre was also delighted to welcome attendees from many other public sector, private sector and not-for-profit organisations including Melbourne Water, the Department of Primary Industries (DPI), Econnect Communication, Acciona Energy and Environment Victoria. The National President of AMOS, Professor Neville Nicholls, opened proceedings with an engaging presentation on the history of climate change science. This presentation served as a timely reminder to everyone that the science underpinning climate change is very old and well established, rigorously peer reviewed, relatively simple, and that predictions made many years ago have since come to fruition. Professor Nicholls was followed by Dr Tahl Kestin from the Monash Sustainability Institute, who offered many insights into improving engagement between climate scientists and decision makers. In particular, Dr. Kestin stressed that in order to have an effect on the decision making process, it was of utmost importance that the science remain credible, relevant and legitimate.
In a similar vein, former Climate Change Minister and Deputy Premier of Victoria Professor John Thwaites, who is now Chair of ClimateWorks Australia and the Monash Sustainability Institute, was able to draw on his many years of political experience to offer advice on how climate scientists and communicators can best engage with politicians. His “ten commandments on influencing government” emphasised, among other things, the need to present a united front and the idea of targeted campaigning towards key individuals such as ministerial advisors. One of the highlights of the workshop was provided by Chris Sounness, who showed some of the work being done by the DPI in communicating climate science to rural communities. An educational, animated video starring “Ridgy” the cattle dog (aka the subtropical ridge), renowned for herding frontal systems away from southeastern Australia during the summer months, was a great example of how to break down communication barriers. Also on the theme of barriers to communication, Adam Morton from The Age newspaper gave a summary of the factors within the journalism profession that can confuse the climate change message. These included insufficient time for proper research, the desire for headline grabbing stories of conflict within the science profession and a lack of scientific literacy on the subject of climate change. Mr. Morton pointed out that the number of dedicated environmental
AMOS President Neville Nicholls takes a question from the audience during the panel discussion. Speakers from left to right: Mr. Adam Morton, Prof. John Thwaites, Prof. Neville Nicholls, Mr. Chris Sounness, Prof. Stephan Lewandowsky and Dr. Tahl Kestin.
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journalists in the Australian media is relatively low. By taking the time to strike up personal relationships with these journalists, the climate science community could go a long way towards influencing the way climate issues are reported in the media. The final presentation of the workshop was delivered by Professor Stephan Lewandowsky from the University of Western Australia, who has published over 100 papers on how people remember and think, with a particular emphasis on the role of scepticism in the updating of memories. His general advice on presenting climate change information was to always state the message affirmatively (e.g. “rainfall will increase” as opposed to “rainfall will not decrease”) and to reinforce the fact that there is strong scientific consensus. He demonstrated that the acceptance of anthropogenic climate change depends primarily on an individual’s ideology, and hence it is also important to tailor the message to the specific audience. When trying to alter the behaviour of a large population made up of many different ideologies (e.g. when attempting to reduce national electricity use) it becomes impossible to tailor the message to everyone. For these cases, Professor Lewandowsky advocated bypassing all attempts to change people’s attitudes and beliefs. Instead, he gave a number of examples of how effective framing of the message, with an emphasis on gently nudging people towards the desired behaviour, was a far more effective approach.
From the six presentations and following panel discussion, a clear pattern of advice emerged. First and foremost, the consistent speculation regarding conflict and disagreement in the climate science community has been problematic. In light of this, it is vital that climate scientists and communicators publically acknowledge the high degree of consensus at all opportunities. It was also clear from the presentations that efforts to influence the political and media spheres would benefit from sustained and ongoing attempts to establish relationships with key individuals. Finally, not only does the science presented to the general public and key stakeholders need to be accurate and correct, it must also be framed in such a way as to take into account the psychology of the target audience (i.e. ideological values, attitudes and past life experiences need to be considered). Upon leaving the workshop, many audience members commented on what a wonderful learning experience the morning had been. As such, on behalf of all those in attendance, the AMOS Melbourne Centre would like to thank each of the presenters for their professional, insightful and highly relevant contributions to the discussion on how climate science can be better communicated into the future. Further information (including slides of the presentations): http://www.amos.org.au/events/id/57
AMOS Weather Tipping Luke Garde The School of Earth Sciences, The University of Melbourne, Melbourne The end of another football season also marks the end of another season of Weather Tipping. Over the past 26 weeks, participants in the annual AMOS Weather Tipping Competition have been testing their forecasting skills across a range of locations around Australasia. This year was the first to make use of a fully redeveloped website and saw a record number of participants from Australia and New Zealand.
The season began with the launch of the new and feature rich Weather Tipping website (thanks to the support of the AMOS National Council, Dr Vaughan Barras and our web designer Mr Michael Allen). Some of these upgrades included an improved user-friendly interface, new security features, user managed accounts and for AMOS members, a graphical visualisation of forecast statistics for each round.
AMOS Weather Tipping is an online weather forecasting competition that operates along the lines of the familiar football-tipping format. However, instead of predicting winners, players are given the challenge of forecasting maximum and minimum temperatures and rainfall for a different location each week.
Of the 71 participants, minor premiership prizes were awarded to the players with the lowest overall errors for each category at the end of the home and away season. This year AMOS congratulates Vlasta Vesely (minimum temperature), Les Muir (maximum temperature) and Tim Slade (rainfall) who will each receive a $30 book voucher. At the end of
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Figure 1: 2010 AMOS Weather Tipping competition top eight scores. The values give the total errors made in forecasting each category. Models are: BoM (Bureau of Meteorology) and OCX (BoM Experimental Operational Consensus Forecast). the “home and away” season the top eight comprised of both “human players”, the Bureau of Meteorology and a “computer player” – a version of the Bureau’s Operational Consensus Forecast system (Figure 1). Following a hard fought finals series (Figure 2) it came down to that one day in September – the forecast for Grand Final weekend in Melbourne. The forecast models were predicting the chance of rain, making the decision for our finalists Richard Finnie and Merlinde Kay more difficult. Thankfully, unlike the 2010 AFL Grand Final between Collingwood and St Kilda, no rematch was required! The result was down to the wire with a total error of one separating the two competitors. I’m pleased to announce and congratulate Richard Finnie as the winner of the 2010 AMOS Weather Tipping competition with a total error score of 109. Richard will receive a book voucher valued at $100. Congratulations Richard! The observations for the Grand Final (Melbourne, 25–26 September 2010) were:
• Saturday: Min 11°C, Max 20°C, Rain 0.4mm (Trace). • Sunday: Min 10°C, Max 22°C, Rain 0.2mm (Trace). For those who participated in this year’s competition, the AMOS Weather Tipping team would like to take this opportunity to thank you for your continued support and enthusiasm for this competition. We hope that you enjoyed the challenge of taking on your friends and colleagues while fine-tuning your forecasting skills and having a bit of fun along the way. We enjoyed bringing the new website to you, which we will continue to enhance over the off-season for next year. Please keep sending through your feedback on how we can improve the presentation of the site. Stay tuned to the AMOS website during next year’s AFL preseason for the announcement of the 2011 competition! Further information: http://tipping.amos.org.au
Figure 2: 2010 AMOS Weather Tipping Finals series. Grand Final winner: Richard Finnie. Bulletin of the Australian Meteorological and Oceanographic Society Vol. 23 page 100
Brisbane Regional Centre Update Michael Hewson Vice chair, Brisbane Regional Centre The Brisbane Centre continues to meet around about every second month. Attendances was good at a forum held on the 16th September at the Bureau of Meteorology offices in Brisbane. Dr David McJannet (Figure 1) from CSIRO spoke about the southeastern Queensland Urban Water Security Alliance’s study of evaporation from water storages (Figure 2). The following meeting, in late October, was a visit to the Bureau of Meteorology forecasting offices. The Brisbane Regional Centre is also planning a Christmas function for late November. The Brisbane Regional Centre committee wants to showcase AMOS and its members in the second quarter of 2011. In the early planning stages is a one day forum on the topic: “Southeast Queensland’s Future Weather and Climate: What it Means for the Community and Government”. The forum is to be held at the Queensland Museum and will consist of presentations from invited speakers on a number of topics. The aim of the forum is to engage environmental management and planning interest groups – whether they are public, private, policy or consulting organisations. Consideration is being given to the following topics:
Figure 1: Dr David McJannet, CSIRO Land and Water Research Scientists (Source: www.csiro.au).
• climate change and variability – implications for Southeast Queensland (SEQ) •
tropical cyclones – a real threat to SEQ?
• thunderstorms – recent and expected trends • the SEQ metropolis and its emissions and what influences the weather? • to what extent is the SEQ shoreline susceptible to inundation? • a moderated panel discussion on how emerging weather and ocean trends might constrain land-use planning and air quality in SE Queensland.
Figure 2: Eddy covariance instrument uses to monitor fluxes in the atmospheric boundary layer. Measuring these fluxes allows calculations of things like evaporation to be made. (Source: LI-COR Environmental, www.licor.com) The forum will possibly be a good time for AMOS members to hang A1 size posters of their work – so here’s a “heads up” for Queensland AMOS members – and more details to follow!
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25th General Assembly of the International Union of Geodesy and Geophysics (IUGG) Melbourne, Australia 28 June to 7 July, 2011. The 25th General Assembly of the International Union of Geodesy and Geophysics (IUGG) will be held in Melbourne from 28 June to 7 July 2011. This is only the second time that an IUGG General Assembly has been held in Australia. The previous one was held in Canberra in 1979. General Assemblies are only held every four years and provide attendees the chance to inform themselves of the latest international research in all areas of fluid earth and solid earth geophysics and geodesy. Registration and call for abstracts are now open! Visit: www.iugg2011.com The planned list of symposia and their convenors can be accessed from the Scientific Program page of the web site at: www.iugg2011.com/program.asp Key Dates FOR IAHS SUBMISSIONS ONLY - Call for Abstract Close Monday 8 November 2010 Call for Abstracts Close: Monday 17 January 2011 Authors Notified of Acceptance: Monday 28 March 2011 Author Registration & Early Bird Deadline: Monday 11 April 2011 _________________________________________________________ IUGG is composed of eight international scientific associations: IACS: International Association of Cryospheric Sciences IAG: International Association of Geodesy IAGA: International Association of Geomagnetism and Aeronomy IAHS: International Association of Hydrological Sciences IAMAS: International Association of Meteorology and Atmospheric Science IAPSO: International Association for the Physical Sciences of the Ocean IASPEI: International Association of Seismology and Physics of the Earthâ€™s Interior IAVCEI: International Association of Volcanology and Chemistry of the Earth's Interior Bulletin of the Australian Meteorological and Oceanographic Society Vol. 23 page 102
Articles Wind waves research in Australia Diana Greenslade1, Mark Hemer2, Graham Symonds3 and Peter Craig2 1
Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, VIC 2 Centre for Australian Weather and Climate Research, CSIRO Marine and Atmospheric Research, Hobart, TAS 3 Centre for Australian Weather and Climate Research, CSIRO Marine and Atmospheric Research, Floreat, WA
Address for correspondence: D.Greenslade@bom.gov.au, Introduction In May 2010, the inaugural Australian Wind Waves Research Science Symposium was held over two days on the Gold Coast, Queensland. The symposium aimed to develop an awareness of related research among Australian waves scientists, to unite waves research across sites and organisations, to discuss future directions and current gaps in the Australian waves research, and to provide a forum for the development of possible collaborative activities. Support for the symposium was provided through the CSIRO Marine and Atmospheric Research Capability Development Fund, along with additional support from the CSIRO Wealth for Oceans Flagship, the CSIRO Climate Adaptation Flagship and the Bureau of Meteorology. The symposium drew approximately 30 invited Australian public sector researchers, and two international invitees, working on various aspects of surface wave dynamics. Participants (Figure 1) came from all over Australia and from a range of disciplines such as meteorology, oceanography and coastal engineering. Three keynote presentations were given by international leaders in waves research: Prof Rob Holman from Oregon State University; Dr Ralf Weisse from the Institute of Coastal Research, GKSS, Germany; and Professor Ian Young from Swinburne University in Melbourne. The meeting was structured into six sessions as follows: nearshore observations and prediction future projections of wave climate wave climate variability and coastal change • wave climatology and historical variability • modelling and forecasting • physics and observations • • •
Four open discussion sessions were also held over the two days. While the presentations described the current state of wave research in Australia, at least in public-sector organisations, the discussion sessions aimed to identify both research gaps and possible directions for the future. For comparison, Prof Rob Holman of Oregon State University, reported on a planning exercise in the USA in which the questions addressed were: a) What are we trying to accomplish with wave research? b) What are the applications? c) What is the current capability? d) What are the existing limitations? He reported a divergence of opinions, particularly on item (d). However, it is worth noting that the outcome of the USA meeting was a recommendation for a long-term observational program focused at one location, collecting data in which trends could be identified, and against which models and predictions could be tested. The Gold Coast symposium was less formalised, but provided a window at least on questions (a), (c) and (d) as applied to the Australian scene. This was the first gathering of Australian wave researchers for many years. The meeting was highly successful and provided a unique opportunity for participants to meet others in similar areas of work where there had not been previous interactions. There was unanimous agreement that this symposium should be the first of a series, with future meetings to be held on a biennial basis, and with a wider range of participants, including, for example, stakeholders and participants from the private sector.
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Figure 1: Participants at the inaugural Australian Wind Waves Research Science Symposium. Back row, L to R: Malek Ghantous, Alessandro Toffoli, Jared Stewart, Ian Young, Murray Rudman, Peter Craig, Jasmine Jaffres, Mal Heron, Russel Morison, Ryan Lowe. Middle row L to R: Chari Pattiaratchi, Tom Durrant, Ian Turner, Jim Gunson, Ian Goodwin, Kristen Splinter, Val Jemmeson, Alex Babanin, Mark Hemer, Tom Baldock. Front row L to R: Diana Greenslade, Julian O'Grady, Grant Smith, Rob Holman, Graham Symonds, James Taylor, Andrew Heap, Ian Coghlan (not present: Jack Katzfey, Richard Manasseh, Ralph Weiss). This short paper represents a summary of the discussion sessions, drawing on the presentations and, to some extent, the questions and answers that followed them. The following sections discuss the research gaps in their context, and the final section presents a summary list of the research questions. Observations Remote sensing At global scales, satellite altimeters provide data on surface-wave variability and trends, but these have limitations and there are dataanalysis challenges. With careful analysis, the combined satellite-altimeter dataset can provide several decades of observations but measurements at this time are restricted to significant wave height and sometimes wave period. These parameters provide no information on wave direction, which is critical for coastal applications. Directional wave spectra can be extracted from satellitederived synthetic aperture radar (SAR) data, but there were no talks or discussion relating to this data stream.
Shore-based radars, both X-band and VHF, are research tools for measuring spatial fields of waves and currents out to a few km offshore. UHF radars (WERA) provide fields of waves and currents to a range of 100 km, and a number of WERA systems have been deployed, or are in planning stage, on the Australian coast as part of the Integrated Marine Observing System (IMOS) Australian Coastal Ocean Radar Network (ACORN) facility. Two presentations made use of the WERA data, but these data seem largely underutilised at this time. Shore-based video cameras (Argus systems) are a proven technology for measuring waves and beach structure on individual beaches. For both radar and video, inverse calculations give estimates of the (changing) bathymetry. Timeseries from radar and video are supplemented by beach surveys and airborne (manned and unmanned) imagery. In situ Australiaâ€™s coastal buoy network is variable in its density around the coast and there are very few directional wave buoys. The network is
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operated by a number of different state and federal agencies, including the NSW State Government Manly Hydraulics Lab, the WA Department of Transport and the Bureau of Meteorology. Some of these buoys are approaching 20 years of continuous deployment and thus provide a valuable dataset for climate-related studies, local analysis and model verification. In discussion, the point was raised that the funding to support this network of buoys has been under threat for several years. Proxies Geological coastal profiles were presented as a method to describe historical wave climate on longer time scales over which instrumental wave records are unavailable. These can be combined with mean sea-level pressure (MSLP) gradient derived proxies for wave direction. Data gaps For coastal management, critical parameters are the shoreline position and the width of the beach. For safe recreational and maritime activity within the surf zone, knowledge of waves and currents is required. Australia has few locations of sustained beach measurements, and no consistent measurement approaches. Neither is there a widely available repository for data. There is a clear need for a national set of coastal observatories, following the IMOS model, using standard measurement techniques and supplying data to a centralised data-base. The observatories could, for example, be based on video installations and in-water wave sensors deployed outside the surf zone. They would be located on beaches selected for their representativeness and sensitivity. They would preferably also be inshore of other measurement installations, such as IMOS reference stations, coastal radars or directional waverider buoys, which would provide offshore conditions as context for the shore-based systems. The standard suite of inshore measurements would be supplemented by occasional or regular surveys done by local operational agencies and researchers. The data would be used to identify variability and trends in the nearshore wave and current regimes, and in the beach structure. Importantly, they would be used to inform and verify models of nearshore and beach process that can be used for application to other beaches, and for prediction. Offshore wave data are being used for development of source terms in spectral wave models (i.e. wind growth and whitecapping
dissipation terms). There was considerable discussion on the need to consider waves in the coupled atmosphere-ocean system. One talk, aiming to quantify the sea-state-dependent surface momentum flux illustrated a lack of data to support this research. Similar data gaps occur in quantifying sea-state dependent mass and heat fluxes. The IMOS Southern Ocean Flux Station mooring has the potential to be developed to support research in this field with the addition of suitable wave measurements at the site. There is some development of wave measurements from the Motion Reference Unit on the IMOS moorings and this has shown some promise, but these require rigorous testing against recognised instrumentation. As mentioned above, the coastal wave-buoy network is adequate in some areas, such as the NSW coast, but there are considerable gaps in the network, particularly for Victoria, the Northern Territory and the east coast of Tasmania. A further data gap is in the gridded representation of the coastal bathymetry at high resolution (10s of metres). At present, Geoscience Australia maintains a 250 m resolution gridded bathymetry for the Australian region. In some nearshore regions, the bathymetric information does exist at higher resolution and there are a number of applications that would benefit from access to these data. Wave modelling Global or basin scale Australian researchers are using a variety of wave models. At large scales, WAVEWATCH IIITM (WW3) is favoured, implemented for operational forecasting at the Bureau of Meteorology (as of June 2010), as well as decadal analysis and climate projections. The possibility of a â€œcommunity wave modelâ€? version of WW3 was raised, which would be potentially hosted and maintained by an organisation such as the Bureau of Meteorology. A community model would require dedicated support, but would benefit the community as a reference point for model support and advice on implementation. Winds for forcing for wave models are sourced from a number of different agencies. It was acknowledged that an understanding of the errors and biases in surface winds is relevant for wave modelling at all scales. Regional At regional scales (10s of kms), SWAN (from Delft) is the most commonly used wave model,
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but there are one or two applications of MIKE21 (from DHI, based in Denmark). WW3 may eventually also prove to be effective at this scale as more shallow water physics are incorporated. In coastal applications, the input data are a more serious problem than the model physics. Offshore boundary conditions are derived from buoys and/or global models, which are not always in exact agreement. The biggest issue is bathymetry. There are data from various highresolution (10s of metres) hydrographic surveys, LIDAR and/or LADS surveys and hyperspectral flights, but the coverage is sparse, and there is no unified central database. Such surveys do not replace the need for local measurement (see above) within the surf zone, where the bathymetry may change on time scales of hours. Nearshore Within the very nearshore region (10s of metres), a number of models such as XBeach, Delft3d (both from Delft), and the NearCOM package (University of Delaware) were all mentioned. The community in general seemed satisfied with these nearshore models. There is active research on wave-current interactions in the nearshore. One application is lowfrequency motion driven inside lagoons by waves breaking on reefs. Another is longshore currents driven by waves breaking on a bar. XBeach is still under development and has shown promise, but like other existing nearshore models, it still presents some challenges to modellers in terms of the domain specification and parameter choices. Furthermore, it is only two-dimensional. Three-dimensional models, such as the coupling of SWAN and ROMS, will be more challenging, particularly for verification of model behaviour. XBeach, Delft3d and NearCOM include morphodynamics. Morphodynamics are often the motivation for coastal model applications, but this component of the models is still very empirical. There is currently little experience with implementation, calibration, verification and correction of such models within Australia. This, and the accompanying data collection, is likely to become a compelling research activity. Carefully designed field programs are likely to advance the process representations in morphodynamic models. There were no talks on phase-resolving models â€“ that is, models that solve some form of the hydrodynamic equations, rather than invoking the spectral approximation. This appears to be a gap in Australian research. However, there
were presentations on specific models, for example, a Lagrangian model of the swash zone, and another using smooth-particle hydrodynamics (SPH), a Lagrangian approach developed in computational fluid dynamics. SPH, in particular, is very different from conventional wave modelling. There appears to be a real research opportunity to use such a model in comparison with more conventional models, given that the former can represent processes such as wave breaking or interactions with structures, which must be parameterised in lower resolution models. One specific process that could benefit from the use of this approach is the role of the wind-water interaction in the surf zone. Another new research area for nearshore wave models is the incorporation of data assimilation. In atmospheric, ocean or largescale wave models, data assimilation is used to correct, or improve the initial values of model state variables. In the emerging approaches to coastal wave modelling, the assimilation of radar or video information, for example, can be used to deduce and correct the bathymetry. Wave Climate The CSIRO atmospheric model CCAM is being used to downscale Intergovernmental Panel on Climate Change (IPCC) atmospheric models, and drive predictions of wave climate. There is large uncertainty in the projections, which show strong regional variability associated with the forcing scenarios, global climate model biases, and the wave-model error. The wave-climate research aims to explain and quantify this uncertainty. During discussion it was suggested that the wave models may help diagnose problems in the ability of the climate models to adequately describe atmospheric circulation. There were several presentations and considerable discussion around available products and their ability to characterise present climate. The discussion included existing reanalysis datasets (ERA-40 and CERA40, ERA-INTERIM), wave model archives (HI-WAM) and the 23-yr altimeter database. These products can all be used to describe the present wave climate, but all have their problems. There is a perceived need for a high-resolution Australian-region wave reanalysis, combining in situ observations, the long-term altimeter record and a highresolution model. It is worth noting that the US National Centers for Environmental Prediction (NCEP) are planning to run a 1979-2009 global waves hindcast using WW3 forced with the recently available NCEP Climate Forecast
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System atmospheric Reanalysis (CFSR). The NCEP CFSR has high spatial (approximately 0.5 degree) and temporal (1-hourly) resolution, and has the potential to be a valuable dataset to describe storm wave systems (99th percentile statistics).
research challenges that were identified at the Symposium, listed in no particular order:
Several speakers noted the IPCC statement that there is little to no ability to predict changes in coastline. This is true on time scales of days, let alone decades. Defining the impact of climate-change on the coastline is a major research challenge.
• implement and validate techniques for near-shore bathymetry
There was some discussion on the role of waves in the coupled ocean-atmosphere system. At present, waves are represented in climate models only through wind-dependent parameterisation of the surface (momentum, mass and heat) fluxes. There are suggestions that waves may have a more profound impact, particularly on surface ocean mixing, the position of storm tracks, and the oceanic uptake of gases. For example, Eulerian ocean models do not explicitly represent Stokes drift or Langmuir circulation. Atmospheric climate models do not consider sea-state dependent drag on the sea-surface. There are other wavedriven feedbacks in the climate system which need further attention (e.g. storm driven seaice dynamics and albedo influences of whitecapping). Over climate time-scales, even subtle effects may be important. The role of these two-way feedbacks in the coupled climate system is a considerable research question. Summary The wave-research community in Australia is relatively small, especially given Australia's dependence on its coast. Existing wave-related research projects tend to be locally motivated and implemented, often because they have a coastal focus. There appears to be a clear need for continued communication across the community. Further, Australian coastal researchers, in particular, need to ensure that they remain connected with the international community, even though present funding mechanisms do not necessarily encourage international projects and partnerships. The list of research challenges developed in the symposium's discussion sessions is too long for the current community to address, and would be too expensive to implement within present budgets. This document does not attempt either to prioritise the research imperatives, or to identify funding opportunities. The following is a list of
establish a coastal observing network
• establish a gridded, consolidated highresolution bathymetry for nearshore Australia inverse
• improve source-term formulations conventional spectral models
• resolve differences in global model predictions and coastal buoy measurements • broaden the Australian wave modelling base to include phase-resolving techniques and new approaches such as smooth-particle hydrodynamics • nurture skills in the emerging area of nearshore data assimilation, incorporating both measurement and modelling • expand skills in, and familiarity with, coupled wave-current-morphology modelling • assess and improve climate-scale wave models by comparison with appropriate timeseries (satellite and fixed-point measurements, and model reanalysis) • develop techniques for climate-time-scale coastal prediction, verified against historical data • develop theories of wave-current interaction applicable to basin-scale circulation • encourage the integration of wave models in fully coupled ocean-atmosphere-wave systems over a range of space and time scales. Acknowledgments All the participants at the Symposium are thanked for their valuable contributions to this article. References Extended abstracts providing further details of the current state of wave research in Australia can be found in: Day, K.A. (editor), 2010. Proceedings of the Australian Wind Waves Research Science Symposium, CAWCR Technical Report No. 29. Available from http://www.cawcr.gov.au/ publications/technicalreports/CTR_029.pdf Note: This paper has been adapted from a summary paper that appears in the above Proceedings.
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Meet a Member Every issue, an AMOS member is selected at random and emailed some questions about who they are and what they do. This issue we meet AMOS student member Robert Huva. Where does this email find you? At Uni! Yep, another day in the Honours room at Melbourne University. It’s actually not that bad a room. With north-facing 4th storey views I’ve seen many a storm roll in over Carlton from my desk. What do you do? As you could probably guess from the above, I am an Honours student at the University of Melbourne. This year I am studying the variability of wind and solar radiation across Victoria using a numerical weather prediction model. The main aim is to find the best combination of the two resources (wind and solar) that provides an energy output to match demand. The beauty of my project is that the use of a gridded model allows me to analyse all of Victoria, without the limit of a comparatively sparse observational network.
recommendations can be made from mine or others’ work is quite cool. What did you want to be when you were 10? I think I either wanted to be an AFL footballer (because I was the longest kick in my year level) or a rock star (because I had then been playing guitar for about 3 or 4 years). How do you relax? Pizza and beers while watching the footy with mates. Makes for a nice end to the week most Friday nights! What is your favourite holiday destination? Definitely Vancouver... I have so many family members over there. It’s always nice to visit them, but the skiing (or rather snowboarding) conditions are also so much better than Australia!
Why did you get into it? I majored in meteorology and climatology in my undergraduate science degree and wanted a taste of research, so Honours sounded like the perfect fit! It’s only an extra year and so far I have enjoyed it. The project itself interested me because of the implications it could have on changing the energy industry’s perspective on renewables. I’d like to think I could be part of that inevitable change-over to renewable energy. What is the best thing about what you do? I think it’s the sense of discovery. Sure, there are already wind farms in Victoria and people are increasingly installing photovoltaic cells on their roofs, but production on a large scale is entirely different and needs more research before we commit to large projects. Starting from scratch, building on the output from the model and then getting to the point where .
Melbourne University Honours student Robert Huva on a snowboarding holiday.
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Significant Mesoscale Oceanography News JCOMM ET-OOFS meeting The Expert Team for Operational Ocean Forecasting Systems (ET-OOFS) met at the Japan Meteorological Agency, Tokyo, 7–9 October. This team is endorsed within the WMO-IOC Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM) to provide the international coordination of operational ocean forecasting systems. The overall aim of the team is to improve the quality of forecasts and promote best practice in the delivery of ocean services by national agencies and institutes. Key activities include:
Satellite altimetry is also in a transition state. With the Jason-1 satellite well beyond its mission life, it is being debated whether to continue operating it in a repeat orbit. The decision is pending the recommendation from the OSTST (Ocean Surface Topography Science Team) meeting that was recently held in Lisbon. The Envisat satellite is also scheduled to move into a non-repeat orbit, which may mean a loss in quality for observing regions where the mean dynamic topography already has a large error. Altimetry coverage and accuracy is vulnerable to further losses as the quality of the scheduled high accurate oceanography altimeter AltiKa is not yet known.
• drafting a guide to operational ocean forecasting • specifying both an agreed and common set of observational requirements and user requirements •
Global Ocean Data Assimilation Experiment OceanView (GODAE) Science Team meeting The GOVST met at Japan Agency for MarineEarth Science and Technology (JAMSTEC), Tokyo, 4–6 October. This team seeks to provide international coordination of research to extend the capability of ocean forecasting systems. Key activities include: •
observing system design
coastal ocean prediction
Operations Real-time ocean observing system has undergone several adjustments in the past months with more scheduled in the near future. The Argo Global Data Assembly Centres (GDACs) are implementing a change in file format to separate the delayed mode and near real-time automatic quality controlled profiles. This change will reduce the data volumes and improve efficiency of pre-processing. However this transition has unfortunately resulted in a period of no profiles from the GDACs although the Global Telecommunications System (GTS) have continued operation.
Figure 1: a) Sea surface temperature for the Tasman Sea, 11 September, 2010 and b) sea surface temperature for the Coral Sea 1 September, 2010. Source: www.bom.gov.au/ oceanography/forecasts/index.shtml
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Ocean conditions The east coast of Australia has seen an early onset of the East Australian Current, having already established a robust volume and heat transport along the northern NSW coast (Figure 1a). The onset can be traced to stronger easterly trade winds and South Equatorial Current (SEC) transport (Figure 1b), consistent with the La Niña conditions that preceded in the tropical Pacific. The Leeuwin Current has persisted into September following a typical seasonal cycle. The transports of warm/saline water masses over the past few months can be traced along the southern coast of Australia. The past two months have continued to see surging along the southern coast in response to frontal systems from the Southern Ocean as discussed in detail below. The northwest Australian region has similarly progressed through a typical seasonal cycle with the mixed barotropic/baroclinic instability breakdown of the SEC in response to the seasonal weakening of trade winds. Subsequently there is a steady warming of the surface water forming a warm pool within the Timor Sea, which precedes the Australian monsoon. Coastal sea level The introduction of the trial coastal sea level observational network now provides routine monitoring of high and low sea level events at specific locations around the Australian coastline. The available sites relate to those tide-gauges currently available in real-time within the Bureau of Meteorology. Coordination of additional third-party tidegauges is in progress. In the past two months three stations have reported sea levels exceeding the highest astronomical tide (HAT). 1. Broome (WA): the sea level exceeded HAT between the 9–12 September 2010 with a the highest sea level of 0.8 m above HAT
(10.5 m) occurring with the peak tide on 11 September. The high sea level was accurately forecasted by the total sea level product. 2. Thevenard (SA): the sea level exceeded HAT on the 9 September with a highest sea level approximately 0.4 m above HAT (2.6 m) attributable to 0.4 m of non-tidal sea level. The non-tidal coastal sea level of 0.4 m in the Great Australian Bight is relatively modest however it coincides with a high astronomical tide. This was in response to local winds from cold fronts (see Figure 2).
Figure 2: Mean sea level pressure over the Australian region on 9 September 2010. Source: www.bom.gov.au/australia/charts/ synoptic_bw.shtml. 3. Spring Bay (TAS): the sea level exceeded HAT on the 10th September with a highest sea level approximately 0.1 m above HAT (1.4 m) attributable to inverse barometer (0.25 m). Further information: www.ioc-unesco.org/index.php? option=com_oe&task=view EventRecord&eventID=651 www.godae-oceanview.org/ outreach/meetings/govst-ii-meeting/ www.ostst-hydro-2010.com/index Colour versions of these figures can be found in the online version of the AMOS Bulletin – Ed.
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Double Rainbow Vaughan Barras Primary and secondary rainbows following a passing shower outside the Bureau of Meteorology building in Melbourne, 26 August 2010. Any theory of the rainbow that approximates the behaviour of light as a ray attributes the secondary bow to light that has undergone two internal reflections. The losses accompanying the additional reflection account for the bow being fainter than the primary bow, and the approximate positions and colours of the primary and secondary bows. The dark region of the sky seen between the primary and secondary rainbows is known as Alexanderâ€™s
dark band, after Alexander of Alphrodisias who was the head of the Lyceum at Athens from 198 to 211 A.D., and is credited as the first person to have commented upon the phenomenon (Source: AMS Glossary, amsglossary.allenpress.com/glossary). Image reproduced with permission from Vaughan Barras. Thank you to Vaughan and all the members who sent in their snapshots for this issue. If you have any photos you would like to share, please send them to me via the address on the back cover. â€“Ed.
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Significant Weather August Thunderstorms New South Wales Sydney experienced a short thunderstorm on the 15th. Heavy bursts of rain and small hail were reported from Normanhurst to Dee Why. Northern Territory A thunderstorm on the 27th dealt Mt Snow in the Northern Territory 68 mm of rain in one hour, and 85.6 mm over a three-hour period. This storm resulted in the 4th wettest August day on record for the NT. Victoria On the 10th severe thunderstorms occurred in Northern Victoria. A tornado was reported, photographed and filmed near Echuca-Moama on the NSW/Victorian border. The SES reported one house partially de-roofed and damage to vegetation. The 18th saw a trough that produced several severe and supercell thunderstorms move through western Victoria and into central areas during the night. Hail up to the size of a 20 cent piece was reported in Netherby, and golfball sized hail fell at Kerang and Cohuna, as did some trees. Flash flooding occurred near Wedderburn. Later in the night the Kerang storm affected the Yarrawonga region and produced damaging winds. Rainfall and Flooding Queensland At the end of July, a strong band of storms and rain led to flooding that continued into August in the Lower Macintyre and Paroo Rivers. The Lower Macintyre River remained minor to moderately flooded throughout August. Another more widespread rain band moved over the state from the 10th to the 12th, causing minor local flooding in areas of southeast Queensland. The Dumaresq River was also flooded between the 23rd and 25th. Victoria August was a very wet month for Victoria, with 194 flood watches and warnings issued over the month. Most of the warning were minor in nature, and were generally related to rivers north of the Dividing Range. Continued rainfall on top of already saturated catchments was the cause of the majority of warnings.
Seven moderate flood warnings were issued, six of these in the Barwon and Leigh river catchments upstream of Geelong. These warnings were accurate, as moderate flooding was experienced upstream of Geelong. This also led to a recorded peak of 2.1 m (just under the minor flood level of 2.5 m) at Geelong on the 15th. The Kiewa catchment in the stateâ€™s north recorded a total of 24 flood warnings over the month. The forecast point at Bandiana spent most of that time above the minor flood level of 2.7 m. The low-pressure system that crossed the southeastern part of the country on the 10th, 11th and 12th, also brought severe weather to Victoria. The Western district recorded very heavy rain on the 11th, and many areas in the southwest broke records for the wettest August day. Apollo Bay, Weeaproinah and the Cape Otway Lighthouse recorded almost half their monthly average on one day. Several flood warnings were issued and many roads in the area were submerged. The largest two-day rainfall totals were at Weeaproinah (202.2 mm), Haines Junction (135.4 mm), Apollo Bay (105.2 mm) and Lorne (90.4 mm) Tasmania Eastern and central Tasmania experienced heavy rainfall on the 10th and 11th, due to a slow-moving low-pressure system that formed over the continent and moved across the southeasten part of the country into Bass Strait. The state recorded one of its wettest days in instrumental history. Many sites in the east received their highest August rainfall on record, with over 100 mm falling over much of the region. Mount Wellington received 199.4 mm, while 182.0 mm fell at Gray (Blueberry Cottage) and 175.2 mm at Gray (Dalmayne Road). These totals are the 2nd, 3rd and 5th highest rainfalls recorded anywhere in Tasmania during August. Flash flooding and landslides associated with the heavy rain closed roads and isolated several towns. St Helens, Binalong Bay, Pyengana, Fingal, St Marys, Ansons Bay, Cranbrook and Claremont all experienced road closures, as did other areas. Several were still not open on the morning of the 12th. Rivers flooded over the majority of the Midland and northeast regions. The South Esk,
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Break O’Day, St Paul and Macquarie rivers experienced moderate to major flooding, while minor flooding occurred in the North Esk river basin. The North Esk River peaked early on the 12th, when a river height of 3.1 m was recorded at Corra Linn. A major flood also affected Llewellyn early on the 12th after the main flows of the South Esk and St Pauls rivers joined overnight. A peak river height of 8.5 m was recorded. The Macquarie River peaked on the night of the 11th at Mount Morriston with a height of 2.6 m. These waters then moved downstream in the following days, causing minor to moderate flooding in the lower parts of the river from the 12th. The river reached 2.6 m near the Ross Bridge, and then peaked at 4.3 m at Westmoor Bridge on the 13th. Minor flooding in the area continued until the 18th. Perth on the South Esk River peaked at 7.5 m early on the 13th, Longford peaked at 4.3 m in the afternoon of the same day. Flooding of the Scamander River in the state’s northeast caused problems when pipes from a water treatment plant that was under construction were washed out to sea by the floodwaters. An issue with drinking water quality in Campbell Town worsened when the nearby Elizabeth River flooded, and the Hobart Rivulet came within one metre of flooding. More than 300 homes and businesses also experienced telephone line problems due to the rain. Snowfall Victoria Cold air moved over the state on the 25th and 26th, bringing heavy snowfalls. 54 cm of snow fell at Falls Creek over 24 hours, while 47 cm fell at Mt Hotham and 34 cm at Mt Buller. Tasmania Tasmania had many snow days in August, mainly in the second half of the month. Heavy snow fell in the west and Central Highlands on the 16th, behind a strong cold front. Settled snow was reported as low as 200 metres above sea level in the south, but falling snow was seen at much lower levels including the Hobart suburbs of West Hobart, Lenah Valley and Kingston. Hobart’s temperature dropped to 3°C at 4.30pm, with an associated snow shower. Cradle Mountain was covered with snow to around 300 m, and snow covered the ground at several places, including Waratah, Collinsvale, Fern Tree and Oatlands..
Further snow fell on the 19th and 20th behind another cold front. This event caused snow that settled to around 450 m in the south and 600 m in the north. Another cold burst on the 26th to 27th saw snow settle to about 400 m. The snow on Ben Lomond near Launceston was described as the “best snow cover since 2004” after snow overnight on the 25!26th. At least 1 metre of snow had accumulated in some spots. The cold conditions caused a number of livestock deaths. Some calves near Circular Head died during the night on the 19!20th, and there were reports that over 2100 recently shorn sheep in the Bothwell district died due to the adverse weather conditions during the cold period. Winds New South Wales An East Coast Low passed through New South Wales on the 2nd and 3rd of the August, causing very strong winds across the Sydney metropolitan region and South Coast. Maximum wind gusts of 122 km/h were recorded at Jervis Bay on the 2nd, while 107 km/h was observed at Sydney Airport on the 3rd. Wind damage related to fallen trees and roof damage occurred as a result, particularly in the Metropolitan region. Over 1350 calls were made to the State Emergency Services. Victoria The deep low-pressure system over Victoria between the 10th and 12th caused strong wind gusts in the south. Recorded winds included 148 km/h at Mt Wiliam, 109 km/h at Ben Nevis, 107 km/h at Wilsons Prom and 102 km/h at the Cape Otway Lighthouse. The Victorian SES received over 1000 calls for help, most relating to traffic hazard being caused by fallen trees. A strong northerly wind flow developed across the state on the 18th, in front of a cold front and trough. Higher areas in the west were hit with wind gusts greater than 90 km/hr, with 96 km/h at Mt William the highest. Gusts greater than 100 km/h were recorded at the Thredbo Automatic Weather Station on the 15th, 24th and 25th. The Green Cape Lighthouse also measured gusts of 102 km/h on the 12th. Northern Territory On the 17th and 18th, synoptic conditions set up a tight pressure gradient through central Australia. The strongest winds observed were at Yulara Aero on the 17th where the 10 minute
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mean wind measured 50 km/h and the strongest gust measured 70 km/h. Alice Springs Airport also recorded a gust of 70 km/h on the 18th. Tasmania
passed just to the south. This was the windiest day of the month for many sites, particularly in the northwest where around 1500 premises lost power in the morning. Gusts reached 137 km/h at Cape Grim, 94 km/h at Strahan, 91 km/h at Smithton and 85 km/h at Devonport Airport.
Strong west to northwest winds blew across Tasmania on the 20th as a low pressure system
September Thunderstorms Victoria On the 4th, an isolated supercell storm formed along with other cells on a line from Graytown, Victoria to Finley, NSW. The supercell tracked from Graytown to Broadford and produced a weak tornado near Broadford which caused minor damage to a farmhouse and native vegetation. Discrete severe thunderstorms developed on the 9th along a trough between Warrnambool and Horsham in relatively marginal instability and reasonable vertical wind shear. A storm near St Arnaud produced large hail and funnels. New South Wales/Queensland On the 14th numerous severe thunderstorms occurred in western NSW and into southeast Queensland. An impressive supercell with a well-defined hook passed near the new Gunnedah radar and reportedly produced large hail up to 5 cm, and damaging winds. The long-lived cell persisted and reached the coast some four hours after initially forming. Elsewhere a funnel was reported with a hailproducing thunderstorm near Lismore. Rainfall and Flooding Tasmania Heavy rain fell across most of Tasmania on the 4th, thanks to a deepening low-pressure system that came from the northwest. Up to 25 mm had fallen by 9am in the northwest. A further 81 mm fell at Mount Victoria in the following 204 hours, with 75 mm recorded at Mount Barrow and 63 mm at Mount Read. Associated flooding occurred across most rivers in northern Tasmania.
major flooding. The system dumped daily rainfall totals of more than 60 mm, particularly to the north of the divide. Significant damage occurred around Ballarat, Wangaratta, Euroa, Myrtleford, Charlton, the greater Bendigo area, and along the Kiewa River. There were numerous road closures across the state from water over roads, with bridges damaged in the Upper Yarra catchment, and roads washed away in the northeast. Moderate flooding occurred along the Murray, Kiewa, Mitta Mitta, King, Acheron, Avoca, Broken, Loddon, Ovens, Buffalo, Campaspe, and Buckland rivers. Minor flooding was reported along most other catchments. Winds Tasmania An 18.4 m wave was recorded off Cape Sorell on the morning of the 16th during a day of big waves. Observers at Maatsuyker Island off Tasmaniaâ€™s south coast also reported an exceptional 11 m swell on the 16th. The huge waves were generated by strong winds from a deep low-pressure system to the south of Tasmania. Wind gusts on land reached 148 km/h at Maatsuyker Island and 141 km/h at Cape Bruny. Rain, hail and snow were also associated with this system, and road closures, building damage and failed power lines were reported across the state. Thunderstorm information, and details of Victorian flooding in September contributed by John Allen. Additional information derived from the Bureau of Meteorology monthly weather reviews. Further information:
Extensive flooding occurred across much of the northeast of the state. A single lowpressure system that originated in the tropics crossed the state from the 4th to the 6th, causing
While all care has been taken to ensure accuracy, this summary is by no means exhaustive. If you would like to contribute to this section, please get in contact â€“ Ed.
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Charts From The Past by Blair Trewin 3 October, 1993 The spring of 1993 started very wet in southeastern Australia. September was Victoriaâ€™s third-wettest on record, and turned out to be the last month until August 2010 in which the statewide average reached 100 mm (something which happened nearly once a year on average â€“ 74 times in 94 years - up until 1993). There was major flooding in midSeptember in Gippsland and on the Maribyrnong in Melbourne, as well as widespread minor and moderate flooding on northern Victorian rivers. This meant catchments were very wet as the month ended. A cutoff low formed in the Bight on 2 October, moving east to be centred near Adelaide on the morning of the 3rd and Wagga Wagga on the 4th, before moving out to sea. The system had a strong infeed of moisture and there were heavy rains in the northerly flow ahead of the low. The event started with outbreaks of severe thunderstorms in South Australia on the afternoon of the 2nd. Hail 4 cm in diameter was observed at Wirrulla on the Eyre Peninsula, whilst Woomera experienced damaging winds, and Ceduna had 64 mm of rain in 2 " hours (including 33 mm in 47 minutes). The thunderstorms continued on the 3rd, with 4cm hail again reported that day, this time in the Riverland, with substantial damage to fruit crops. The heaviest rain, though, was concentrated in Victoria, especially northeast Victoria. It was particularly heavy in the northern foothills of the Alps and adjacent plains. Numerous stations in this area had daily falls exceeding
100 mm to 0900 on the 4th. Edi Upper, south of Wangaratta, had 234.4 mm, the highest daily fall on record in northern Victoria, and Mount Buffalo 212 mm. At lower elevations, Benalla had 177.4 mm and Harrietville 157 mm, both all-time records for those sites, whilst other notable falls included 142 mm at Bright and 120 mm at Shepparton. Victoria also saw some severe thunderstorms experienced further west, mostly in the form of very heavy rain, with hourly falls of 68 mm at Gunbower and 51 mm at Kerang. This rain brought major flooding to all rivers in the region, with record flood levels at many locations in the Broken and Ovens catchments. Benalla was most severely affected, with much of the town (including the central business district) inundated and damage running into the millions of dollars. Myrtleford, Bright, Mount Beauty and Wangaratta were also significantly affected, although central Wangaratta escaped significant damage. Shepparton also escaped major urban inundation, despite the Goulburnâ€™s second highest peak on record, but crop damage was considerable. In New South Wales, where rainfall totals were lighter (outside the mountains, peaking at 80 mm at Wentworth on the 4th and 67 mm at Temora on the 5th), there was still major flooding on the Murrumbidgee at Gundagai and the Lachlan at Forbes, although flood levels eased downstream. Relatively dry conditions for the remainder of the month also limited the extent of flooding downstream in the Murray.
Synoptic chart for 0000 UTC (1000 AEST), 3 October 1993
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4–8 Greenhouse 2011: The Science of Climate Change, Cairns.
1–5 US CLIVAR Reanalysis Conference, Baltimore, USA. December
10–15 34th International Symposium Remote Sensing of Environment. Sydney.
7–10 IEEE Sixth International Conference on e-Science, Brisbane.
27–29 2nd International Conference on Physical Coastal Processes, Management and Engineering, Naples, Italy.
13–17 AGU Fall meeting, San Francisco, USA.
13-17 EFS Extreme Environmental Events, Cambridge, UK.
27–8 July IUGG XXV General Assembly, Melbourne. September
2011 January 23–27 91st AMS Annual Meeting, Seattle, USA. February 11–13 18th AMOS National Conference (joint with NZMetSoc), Wellington, NZ.
4–9 10th International NCCR Climate Summer School Climate Change, Extremes and Ecosystem Services, Grindelwald, Switzerland. 19–21 19th International Conference on Modelling, Monitoring and Management of Air Pollution, Malta.
Australian Meteorological and Oceanographic Journal. Vol. 60 No. 3, September 2010. Special issue – Cyclone Tracy revisited Articles: Holland. Tracy revisited: historical perspective, synoptics, track and winds.
Walker. A review of the impact of Cyclone Tracy on building regulations and insurance.
Holland. Tracy: a personal perspective.
Leicester and Reardon. Impact statistics of Tracy and an opportunity missed.
Courtney and Shepherd. The benefit of hindsight: re-examining the maximum winds during Tropical Cyclone Tracy. Davidson. On the intensification and recurvature of Tropical Cyclone Tracy (1974). Le Marshall and Leslie. Tropical Cyclone Tracy – numerical guidance then and now. Harper. Modelling the Tracy storm surge – implications for storm structure and intensity estimation.
Schofield et al. Assessing the impacts of tropical cyclone Tracy on residential building stock – 1974 and 2008. Jones. Managing the national response: the Canberra story. Further Information: www.bom.gov.au/amoj
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2010 Bulletin of the Australian Meteorological and Oceanographic Society ISSN 1035-6576 Editor
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Linden Ashcroft School of Earth Sciences The University of Melbourne VIC 3010 Phone: 03-8344 7672 Fax: 03-8344 7761 Email: firstname.lastname@example.org Stewart Allen Email: Stewart.Allen@bom.gov.au Diana Greenslade Blair Trewin Andrew Watkins Keith Barnett
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Contributed articles, news, announcements and correspondence for the Bulletin should be sent to the editor no later than the 18th of November 2010. They will be reviewed and the galley proofs returned to the author if requested. An ASCII version of the text is required via e-mail or digital media to minimise typographic errors. The Bulletin of the Australian Meteorological and Oceanographic Society is produced and distributed with the assistance of CSIRO Marine and Atmospheric Research and the Bureau of Meteorology. AMOS Web Site: http//www.amos.org.au/