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AMOS

AustralianMeteorological & OceanographicSociety

Bulletin of the Australian Meteorological & Oceanographic Society Vol 25, No.5, October 2012 ISSN 1035-6576


Contents Editorial ..........................................................................................................................................................................72 President’s Column ........................................................................................................................................................72 News ..............................................................................................................................................................................73 News from the Centres ..................................................................................................................................................77 Obituary — Bruce Rutherfurd Morton ........................................................................................................................78 Conference report .........................................................................................................................................................79 Science Articles ..............................................................................................................................................................80 K. J. Sadler, A.Pezza and W. Cai— Cool sea surface temperatures in the Tasman Sea associated with blocking and heat waves in Melbourne .......................................................................................................................................................80

Meet a Member .............................................................................................................................................................84 Snapshot ........................................................................................................................................................................85 Charts from the Past with Blair Trewin ..........................................................................................................................86

ISSN 1035-6576 Cover picture: A view from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite to the south of the Great Australian Bight (Tasmania can be seen in the top right corner). The image shows a hole cut out of the marine stratocumulus clouds due to subsidence from an anticyclone. The image was recorded on 5 June 2012. High pressure systems over Australia can also have interesting effects on Melbourne’s weather as shown in the article on page 80. Image: NASA’s Earth Observatory. 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.


Editorial

Improved status of BAMOS science articles It is with great pleasure that I can announce to AMOS members that the Bulletin of the Australian Meteorological and Oceanographic Society (BAMOS) is now listed at a peer-reviewed journal on ulrichsweb.comTM. Th is is an important step in raising the profile of the science articles that are submitted to BAMOS and this will also allow academics to include any published articles in their peer-reviewed publication list (which are useful for grant proposals etc.). Science articles submitted to BAMOS have been subjected to peer-review for some time (usually by the editor and one other anonymous reviewer). However, the papers have not been acknowledged as having been reviewed. By updating the status of BAMOS to peer-reviewed on ulrichsweb. comTM and drafting a proper peer-review policy (which has recently been approved by Council) we now have a clear method of undertaking a peer-review process for science articles that are submitted. The policy states that a section known as “Science Articles” will contain those articles that have been subjected to the peer-review process. While this new section has been incorporated into BAMOS it does not mean that other non-scientific papers (or those not wishing to pursue the peer-review process) cannot still be submitted. Those non-peer-reviewed articles will still appear in the section entitled “Articles” and will still remain an important and vital part of BAMOS. I strongly encourage members to keep sending in any interesting articles for consideration regardless of whether they go through the formal peer-review process or not. This change to BAMOS will also have absolutely no effect on the other regular sections. All of the latest news, conference reports, meet a member and charts from the past (to name but a few) will still remain. The overriding point of this change to the peer-review process is to make BAMOS more attractive as a recognised journal for publishing scientific work. Submitted work should

be relevant and understandable to the wide variety of members within the AMOS community. It is my personal hope that masters and PhD supervisors will encourage their students to submit short articles to BAMOS. Th is could provide a means for students to experience the peer-review process in a slightly less formal capacity than a major international journal, while still being able to formally reference that work in the future. Also, due to the small size of the articles published, BAMOS provides a fast-track route to publication with articles generally reviewed and published within two to four months. Such articles would be great on the curriculum vitae of any early-career researcher. I would also like to see more oceanographic and operational meteorology papers too and this is something I will work towards. The final step in this process, currently in the draft stage, is to produce a formal “submission guidelines for authours” document for BAMOS. The guidelines will be approved by Council and then included in BAMOS continuously. In the meantime, please feel free to contact me if you are intending to submit work to BAMOS and I will send you the guidelines as they currently stand. Overall, making the BAMOS peer-review process more formal is a good step for the magazine and I hope it will encourage members to share their interesting scientific work with the rest of the AMOS community. If any members have any questions or queries then please do not hesitate to contact me using the details at the back of the Bulletin. I would welcome any suggestions from members and I am happy to discuss any concerns also.

Duncan Ackerley http://ulrichsweb.serialssolutions.com/ title/1349745583263/190693

President’s Column

AMOS strategic plan AMOS has functioned successfully as an organisation for nearly a quarter of a century. During this time we have operated on the basis that our main objective is to advance the sciences we cover in Australia, without going into too much detail about defining what that means. Over that time, the scope of what our field covers has changed significantly, and some parts of the atmospheric and oceanographic sciences have a much greater public profile than they once did. Something which we lack as an organisation is a formal strategic plan, or equivalent. Preparing one is now on the agenda of Council; our hope is that we will have something Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 72

in place ready to adopt at the AGM in February. We don’t see having a documented strategic plan in place as being an end in itself (and recognise that many readers will have gone through similar exercises at their workplaces with varying degrees of enthusiasm). Rather, we see this as an opportunity to reassess what our key objectives should be as an organisation, which fi elds we should be active in (and, perhaps, which ones we shouldn’t), and, in the event that we don’t have the funds to support all of the things which we would like to do, which is quite likely, what our highest priorities should be and what our scope is to expand the resources available to us.


Council have had an initial discussion about goals we might consider, consistent with our existing aims set out in the Rules, which are (a) to promote, develop and disseminate knowledge of meteorology, oceanography and related subjects; and (b) to represent and promote the interests of members in respect of matters connected with meteorology, oceanography and related subjects and to present, in general terms, the views of members on those matters. Some ideas which have been floated so far in the process include: t

Facilitating the carrying out, and communication, of the sciences covered by AMOS (e.g. by supporting appropriate conferences and publications)

t

Playing an advocacy role for the sciences covered by AMOS, and achieving the visibility necessary to do this effectively. In recent years we have done this through, for example, making submissions to inquiries such as the 2009 bushfires Royal Commission. (A particular question here is how aggressive we would want to be as an organisation if, for example, there were a serious threat to the future of one or more of the major institutions in which AMOS members are employed).

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Building a community in the sciences covered by AMOS, including those in research, operations and amateur enthusiasts, sharing enjoyment and enhancing the membership experience. A particular area of interest here is what we can do to build more effective links between operational meteorologists and those in the research community.

t

Provision of professional development opportunities in the sciences covered by AMOS.

t

Achieving a level of administrative and fi nancial governance in AMOS sufficient to ensure the organisation continues to function effectively.

Now that Council has had its initial discussion on the subject, we now want to hear from you, as the members of AMOS. We are interested both in thoughts on overall goals we might consider, and on strategies we might adopt to implement those goals. If you have any feedback, we would like to hear it—this can be sent to me by e-mail (b.trewin@bom.gov.au), or by mail to GPO Box 1289, Melbourne VIC 3001. We would like to have feedback by early November so that it can be considered at the November Council meeting. (We will also be running a survey between now and then—a form is included with this Bulletin for hard-copy subscribers, with others being sent a link by e-mail). Once Council has the opportunity to recommend a set of goals, we will then set about documenting this in a detailed plan.

t

Being an independent voice of authority for the profession (in the words of the American Meteorological Society, ‘honest brokers in providing policy-relevant information’), e.g. through statements on specific issues.

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Being an information source for the profession (e.g. through providing job information/career advice).

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Education and outreach to the community at large— including on items of public interest such as weather and ocean monitoring, and climate change. (American Meteorological Society and the Royal Meteorological Society, for example, both see the scientific literacy of the general population as a key goal).

Finally, I would like to note the passing of Bruce Morton. Bruce had a long and distinguished career in the atmospheric sciences, and was one of the figures who was instrumental in the early years of AMOS in the late 1980s and 1990s. His contribution was fittingly recognised some years ago when he was made one of only three Honorary Members of AMOS. A more substantial obituary is published on page 78 of this Bulletin.

t

Recognition of excellence in the profession.

Blair Trewin

News

International Association of Meteorology and Atmospheric Sciences (IAMAS) News Tom Beer

National IAMAS Correspondent

Call for nominations for the IAMAS Early Career Scientist award (deadline: 28 February 2013) IAMAS will present a medal to an early career scientist working in any area of the atmospheric sciences who has carried out excellent scientific research and who has the potential to make a significant contribution in the future. Early career would be taken as a scientist who had earned their highest degree within the last 10 years and were under 40 years of age when nominated.

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 73

Scientists can be nominated for the Medal by the IAMAS commissions, who will seek potential nominees from early career scientists working in their fields. Each commission may nominate only one scientist ahead of an Assembly. Scientists may also be nominated by Members at Large. Nominations for the 2013 IAMAS medal should be received by the IAMAS Bureau by 28 February 2013. The nomination should include a brief (less than 2 page) account of the achievements of the nominated scientist, details of their involvement with IAMAS, a list of their major publications and an assessment of their potential.


The recipient will be decided by an Awards Committee established by the IAMAS Bureau, which will be formed at the IAMAS Bureau meeting in November 2012 in Paris and chaired by an IAMAS Vice President. Membership of the committee will be drawn from the Bureau and Members at Large. The committee will work via email and tele-conference. The medal will be presented biennially at the IAMAS Assemblies. The recipient is expected to be present at the Assembly and give a lecture during an appropriate session. If no suitable candidates are nominated the medal will not be awarded. The recipient will receive an inscribed medal and a certificate signed by the President and SecretaryGeneral of IAMAS. (Prepared by IAMAS VP, Prof. John Turner)

ICPM2012 Workshop on “Atmospheric Model Parameterizations in the Polar Regions”, 12 July 2012 In an effort to begin a discussion on bridging the gap between observations and numerical modelling of the polar regions, the International Commission on Polar Meteorology (ICPM) sponsored a workshop focussed on atmospheric model parameterizations on 12 July 2012. The workshop was hosted by NCAR, following the Antarctic Meteorological Observing, Modeling, and Forecasting Workshop in Boulder, Colorado. An introductory overview was followed by nine presentations on various aspects of observing and modelling in both the Arctic and Antarctic culminating in a summarising discussion. Results from the meeting identified several shortcomings in numerical models. Complicated phenomena such as blowing snow, which are not well understood and observed, present yet more challenges to the modelling community. Furthermore, there are not enough observations in parts of the polar regions, especially the Antarctic (as compared to Arctic efforts). More effort needs to be put into preserving observations already in place, and handling threats to limit or reduce the current observing network. At the workshop, the attendees agreed to establish an e-mail list to keep the discussion going among the community. Additional discussion included support for the Polar Prediction Project. The workshop program including abstracts and presentations is publicly available on the workshop website http://ees.kuleuven.be/icpm_workshop2012/ (Authours: Maria Tsukernik, Irina Gorodetskaya, Thomas Lachlan-Cope, and Matthew Lazzara)

ICDM2012 Workshop on “Dynamics and Predictability of High-Impact Weather and Climate Events”, 6-9 August 2012 The International Commission on Dynamical Meteorology (ICDM) held its 2012 workshop on “Dynamics and Predictability of High-Impact Weather and Climate Events” in Kunming, China. The workshop featured a series of 24 invited lectures from international scientists working on synoptic and climate dynamics and Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 74

covered many aspects of the variability of the atmospheric circulation, including Monsoon systems, the El NiñoSouthern Oscillation, Arctic & Antarctic Oscillations, tropical & extra-tropical cyclones, and extreme events associated with those circulation systems, among others. It also addressed predictability on a wide range of timescales, from weather prediction through to seasonal and decadal climate prediction. The workshop received 185 abstracts and more than 140 participants from 27 countries and regions attended the workshop. The consensus of the participants was that the workshop was successful, interesting and exciting. It provided an unusual platform for exchanges between the climate and weather research communities, and promoted research on highimpact weather and climate dynamics and predictability. The ICDM plans to follow up this successful workshop with further specialist meetings in future years. The workshop program, including presentations, is publicly available on the workshop website http://icdm2012.csp.escience.cn/ . (Authours: Jianping Li, Richard Swinbank and Jenny Lin)

IAMAS Publication Series No. 2 available A new issue appeared in the IAMAS Publication Series (IPS), entitled “International Ozone Commission: History and activities”. It was compiled by Rumen D. Bojkov, Honorary Member of the International Ozone Commission. A number of copies were distributed to the participants of the Quadrennial Ozone Symposium in Toronto. Interested parties can order printed copies (iv + 100 pp. with illustrated text and detailed appendices) from the General-Secretariat (send an Email to Hans. Volkert@dlr.de) or download the complete pdf-file from www.IAMAS.org/Reports/ .

IAMAS bureau meeting in November 2012 The IAMAS bureau meeting is scheduled in Paris, France during 15–16 November 2012, hosted by IAMAS President Dr. Athena Coustenis at the Paris Observatory (Salle du Conseil). The first day of the meeting will be devoted to discussions of collaboration with IAMAS partners and other associations and of the IAMAS contribution to future meetings. The second day will be devoted to IAMAS internal affairs and is reserved for the Bureau and invitees. You are welcome to send your suggestions and comments to IAMAS SG Dr. Hans Volkert (Hans.Volkert@dlr.de) with a copy to IAMAS ASG Ms. Jenny Lin (jennylin@ lasg.iap.ac.cn) by 1 November 2012 if there’s anything you would like to bring to the attention of IAMAS bureau. A glossary of acronyms used in the IAMAS news can be found on pages 59-60 of the August 2012 edition of BAMOS—Ed.


Dr Rob Vertessy to head Bureau of Meteorology Parliamentary Secretary for Sustainability and Urban Water press relaease Renowned water scientist Dr Rob Vertessy has been appointed director of Australia’s Bureau of Meteorology. Dr Vertessy, who was appointed Deputy Director of the Bureau (Climate and Water) in 2007, has been acting as Director since December last year. After a career spanning more than 20 years as a senior water scientist and leading researcher, Dr Vertessy joined the Bureau in 2007 and led the expansion of the Bureau’s role in providing the hydrological information central to the delivery of national water reform. “With his outstanding depth of experience in both research and policy development, Dr Vertessy is ideally qualified to lead the Bureau as it builds organisational resilience and capacity, and responds to new challenges,” said Senator Don Farrell, Parliamentary Secretary for Sustainability and Urban Water.

services it delivers, and in particular the crucial part it plays in shaping Australia’s understanding of and response to climate change.” “The Bureau contributes to the safety, sustainability, wellbeing and prosperity of all Australians.” “It is recognised and respected both domestically and internationally for the essential contribution it makes to all aspects of disaster management including planning, preparation, response and recovery.” “I look forward to working with Dr Vertessy to strengthen this important agency even further”. Source: http://www.environment.gov.au/minister/farrell/2012/ mr20120904.html

“Under his leadership the Bureau will no doubt continue to command respect across the community for the vital

Researching possible links between the Indonesian Throughflow and Australia’s climate CSIRO press relaease Almost two years ago CSIRO oceanographers deployed moorings in one of Australia’s and the globe’s most important ocean currents, the Indonesian Th roughflow, which connects the Pacific and Indian Oceans through the complex system of islands. The moorings will be recovered, their data will be uploaded to the ship’s computers and then they will be returned to the water for a further 18 months. Leading the research team on board Australia’s Marine National Facility research vessel Southern Surveyor is oceanographer Dr Bernadette Sloyan, who is a specialist in ocean circulation with CSIRO’s Wealth from Oceans Flagship. “The heat and fresh water carried by the Indonesian Throughflow are known to affect both the Pacific and Indian Oceans, and so understanding the physical and chemical make-up is important for the future management of natural resource,” Dr Sloyan said. “The current consists of several different layers that occur at different depths, which weave their way through the complex island network; where there are a variety of seabed landscapes affecting the currents, from broad shallow shelves to deep basins.” “We know very little about how this ocean current changes across the seasons and this will be the first time we look at data from these moorings, which have been in place for two years.”

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 75

The moorings consist of sensors recording temperature, salinity, and ocean current, spanning the region from the continental margin to off-shore in water depths of over three kilometres. These moorings are part of the Australian Government funded Integrated Marine Observing System (IMOS). Given the importance of the Indonesian Throughflow to Australia’s climate, IMOS intends to undertake long-term monitoring of the two main passages. Dr Sloyan said IMOS has provided over $1 million in funding to support this work, which will complement existing IMOS observations being collected from the Northwest shelf, Great Barrier Reef, and the East Australian Current. The research team will also conduct oceanographic sampling and mapping work to create a three-dimensional image of the sea floor in sections of the Timor Passage and the Ombai Strait in the area of the moorings. The work is being undertaken with the cooperation of Timor-Leste, who will have two observers on the research voyage. Australia’s Marine National Facility research vessel, Southern Surveyor, is owned and operated by CSIRO, and is available to all Australian scientists. For more information see: www.csiro.au


Southern Hemisphere becoming drier CSIRO press release A decline in April to May rainfall over south-east Australia is associated with a southward expansion of the subtropical dry-zone according to research published in Scientific Reports, a primary research journal from the publishers of Nature. CSIRO scientists Wenju Cai, Tim Cowan and Marcus Thatcher explored why autumn rainfall has been in decline across south-eastern Australia since the 1970s, a period that included the devastating Millennium drought from 1997-2009. Previous research into what has been driving the decline in autumn rainfall across regions like southern Australia has pointed the fi nger at a southward shift in the storm tracks and weather systems during the late 20th century. However, the extent to which these regional rainfall reductions are attributable to the poleward expansion of the subtropical dry-zone has not been clarified before now. Mr Cowan said rainfall patterns in the subtropics are known to be influenced by the Hadley cell, the large-scale atmospheric circulation that transports heat from the tropics to the sub-tropics. “There has been a southward expansion of the edge of the Hadley cell—also called subtropical dry-zone—over the past 30 years, with the strongest expansion occurring in mid–late autumn, or April to May, ranging from 200 to 400 kilometres,” Mr Cowan said. The CSIRO researchers found that the autumn southward expansion of the subtropical dry-zone is greatest over south-eastern Australia, and to a lesser extent, over the Southern Ocean to the south of Africa. “The Hadley cell is comprised of a number of individual branches, so the impact of a southward shift of the subtropical dry-zone on rainfall is not the same across the different semi-arid regions of the Southern Hemisphere,” says CSIRO’s Dr Wenju Cai. The researchers tested the hypothesis that the dry-zone expansion would give rise to a southward shift in the average rainfall during April and May, and questioned

how rainfall across semi-arid regions, including southerncoastal Chile and southern Africa, would be affected. “During April and May, when the dry-zone expansion is strong, rainfall over south-eastern Africa, south-eastern Australia and southern-coastal Chile is higher than over regions immediately to their north,” Dr Cai said. Using high-quality observations and an atmospheric model the CSIRO team found that up to 85 per cent of recent rainfall reduction in south-east Australia can be accounted for by replacing south-eastern Australia rainfall with rainfall 400km to the north. Such a southward shift of rainfall can explain only a small portion of the southern Africa rainfall trend, but none of the autumn drying observed over southern Chile. “For south-east Australia, autumn is an important wetting season,” Dr Cai explained. “Good autumn rainfall wets the soil and effectively allows for vital runoff from follow-on winter and spring rain to flow into catchments.” According to the study an important issue remains as to why the poleward expansion is largest in autumn, and there is still uncertainty about the role of external forcings—such as greenhouse gases—as climate models underestimate the southward expansion of the Hadley cell edge. This research was conducted through CSIRO’s Water for a Healthy Country Flagship, and was funded by the Goyder Institute for Water Research and the Australian Climate Change Science Programme. Wenju Cai, Tim Cowan and Marcus Thatcher are from CSIRO’s Marine and Atmospheric Research division. Cai W, Cowan T and Thatcher M. Rainfall reductions over Southern Hemisphere semi-arid regions: the role of subtropical dry zone expansion. Scientific Reports 2, 702 DOI: 10.1038/srep00702 (2012) Paper available at: http://www.nature.com/srep/

News from the Centres

NSW Centre News Fiona Johnson

Vice Chair and Publicity, NSW Centre The NSW AMOS centre held our inaugural Hunter Valley seminar in September, thanks to the work of committee members Michelle Ho and Anthony Kiem from the University of Newcastle. We had a great night at the Customs House Hotel in Newcastle hearing Peter Dwyer, the Harbourmaster for the Newcastle Port Corporation, talk about the impact of weather on port operations. Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 76

Newcastle is one of Australia’s oldest ports and it is thought that the first exported goods from Australia came from the port around the year 1800 when coal was sent to Bengal. Peter gave a fascinating talk and it was clear that weather and ocean forecasts play an important role in the efficient operation of the port. Peter’s stories of the role of pilots in bringing ships safely through the port entrance and the


changes in technology over the years were also interesting to hear. The talk was complete with a large cargo ship gliding past the window of the hotel. With some good food and a chance to chat before the seminar began, our first out-of-Sydney seminar was a success and underscores

the name change from the Sydney AMOS centre to the more inclusive NSW centre. We look forward to seminars outside of Sydney becoming a regular occurrence on the calendar for next year.

ACT Centre News Clem Davis

Chair, ACT Centre The ACT AMOS branch conducted two very succesful seminars during National Science Week on Antarctica and the Murray Darling Basin. The videos of the talks will be available on the AMOS website very shortly (ACT region).

We are already considering our topics for next year with one likely to be, “The Canberra Fires—10 years after”.

Melbourne Centre News: The Priestley Cup report Nicholas Tyrrell and Luke B. Hande Regional Sub-editors, Melbourne Centre

The annual Priestley Cup soccer tournament was held on 31 August this year. Now in its 14th year the competition between Monash University, Melbourne University, the Bureau of Meteorology (BoM) and CSIRO is always a mix of friendly and fierce rivalry. It’s a round robin format where each team plays three games, with two games being played simulataneously. Refereeing was graciously provided by Blair Trewin and Yuelong Miao. The two proud universities met in the first round; defending champions Monash got in a few early goals, then Melbourne clawed back a couple before Monash pulled away. But the bad news from the fi rst game was that Muhammed Hassim from Melbourne University was sidelined with a bad knee injury, putting him out for the tournament. Meanwhile, CSIRO were showing early promise against the 2009 and 2010 champions BoM, beating them 4–1. The second round was a high scoring one, enjoyed by a growing audience. The two fi rst round winners, Monash and CSIRO were in a hard fought battle for dominance that fell CSIRO’s way 8–5, and the Bureau managed 9 goals against Melbourne’s 5. In the deciding round, CSIRO’s two game winning streak saw them as fi rm favourites against Melbourne, making the BoM vs Monash game a dead rubber, and possibly a bit more light hearted and friendly than the previous matches. When word came in during half time that Melbourne were ahead; the ante was upped and the Bureau were fighting hard. Then a second blow for Melbourne: another injury, another star player down, this time it was Frank Drost. CSIRO pulled away to a 6–2 victory to claim the Priestley Cup. A much deserved victory and their fi rst in 10 years. Celebratory drinks and pizza, kindly organised by CSIRO, were enjoyed by all. Next time you’re applying for a job at an atmospheric science research organisation in Melbourne you may want to add “excellent footwork” to your list of applicable skills.

CSIRO 8–5 Monash Bureau 5–8 Monash Melbourne 2–6 CSIRO

Final Table Team

Won

Drawn

Lost

Goals for

Goals against

Points

CSIRO

3

0

0

17

8

9

Monash

2

0

1

18

15

6

BoM

1

0

2

15

16

3

Melb. Uni.

0

0

3

9

20

0

Action from CSIRO versus Monash University. Image: Jackson Tan.

Results Bureau 1–4 CSIRO Melbourne 2–5 Monash Bureau 9–5 Melbourne Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 77

Priestley Cup winners 2012: CSIRO. Image: Nicholas Tyrrell.


Obituary

Bruce Rutherfurd Morton Michael Manton1, Michael Reeder1 and Roger Smith2

Monash University, Australia LMU, Munich, Germany Bruce Rutherfurd Morton was a kind and gentle man, convinced of the importance of science education, steadfast in his adherence to personal and professional integrity, and committed to building a thriving research community in his fi eld. He was a true scholar, with interests extending well beyond science, being fond of art, music and literature. 1 2

Bruce was born on 11 April 1926 in New Zealand. He was educated at Auckland Grammar and then at the University of Auckland (completing a BSc and MSc), before going to Cambridge on a Rutherford Fellowship. There Bruce completed the Mathematics Tripos and a PhD in the Department of Applied Mathematics and Theoretical Physics, the latter supervised by George Batchelor and Sir Geoffery Taylor. His PhD culminated in the now classic paper Morton, Taylor and Turner, 1956, Turbulent gravitational convection from maintained and instantaneous sources, which is one of the most referenced papers in fluid dynamics. Vorticity as an idea for understanding fluid evolution was a major, recurring theme in Bruce’s work. Among other things, he clarified the processes by which vorticity is generated and, in particular, the role of boundaries. His research on vorticity and convection profoundly altered the field. After leaving Cambridge he took a position at University College in London. However, he did not stay there long as shortly afterwards he was offered a lectureship by Professor (later Sir) James Lighthill in the Mathematics Department at the University of Manchester. One of Lighthill’s great qualities was the unwavering support he showed towards his research group, and this made such a deep impression on Bruce that it became a hallmark of his own professional life. Bruce was appointed to a chair in Applied Mathematics at Monash University in 1967. There he established a strong group in geophysical fluid dynamics within the Department of Mathematics. Bruce believed that laboratory work played an important role in teaching and research and so established a fluid dynamics laboratory in the department. Although Bruce never considered himself to be a meteorologist, the group he built was to have a very strong influence on meteorology in Australia and overseas. For Bruce, meteorology and oceanography were two fascinating and highly relevant applications of fluid mechanics. He retired at the end of 1991, but continued to be involved in science for many years after his retirement. Bruce was a popular and charismatic teacher. Although his lectures were at times a little chaotic, he communicated his great passion for fluid mechanics and deep insights in Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 78

the subject. In his lectures, Bruce would often become side-tracked, perhaps when he thought of some nice analogy or an interesting application and, consequently, students sometimes struggled to compile a coherent set of notes. However, his lectures were always inspirational and stimulating. Bruce was an avid walker. While a student at Cambridge, Bruce resumed his friendship with Sir Edmund Hillary, whom he had known in New Zealand, and together they tramped and climbed the mountains of Austria and Switzerland. Even in later life when walking across the campus to a lecture or meeting, Bruce always set a cracking pace and strode along as if he were still walking with Hillary. Often, this caused some difficulty for his students and colleagues who sprinted along beside him, all the while trying to carry on a conversation as he sped to his next appointment. Bruce believed very strongly in building research communities. Although often busy, he was generous with his time, always available for a chat with students and colleagues seeking advice. He invested a lot of time and effort into the development of the Australian Meteorology and Oceanographic Society, serving as President and Vice President among other roles. Th is involvement with the Society continued for many years after his retirement. While at Cambridge, Bruce married Alison, whom he had first met while still at the University of Auckland. He was devoted to Alison and she to him. Sadly Alison died three months before Bruce and he felt her loss very deeply. Until the later part of his life when he was increasingly troubled by ill health, Bruce seemed to have unlimited energy and enthusiasm for everything he undertook. He was an inspiration to all who knew him well, an outstanding role model for his students and colleagues, and will be sadly missed by the Australian Meteorological and Oceanographic community. He and Alison are survived by their daughters, Clare, Janne and Anna, and seven grandchildren.

Professor Bruce Morton with a flow tank being built in the Geophysical Fluid Dynamics Laboratory. Monash University Archives. Image: Richard Compton


Conference report

20th Symposium on Boundary Layers and Turbulence/18th conference on Air-Sea interactions 8-13 July 2012, Boston, USA Luke B. Hande

Monash University The beautiful, historic and vibrant city of Boston, Massachusetts, hosted a joint meeting sponsored by the American Meteorological Society (AMS). The 20th Symposium on Boundary Layers and Turbulence and the 18th Conference on Air-Sea Interaction shared the venue of the Westin Hotel to present the latest research in their respective fields. For the most part, the two conferences ran separate parallel sessions, two streams for the Boundary Layers and Turbulence attendees, and one for the smaller Air-Sea Interaction crew. However there were a few joint sessions, which highlighted the interdisciplinary nature of much of the research, in particular research into costal and marine boundary layers. Also, a large part of the third day of the conference was devoted to presentations regarding the Dynamics of the Madden-Julian Oscillation (DYNAMO) field campaign. The Boundary Layer and Turbulence sessions spanned analysis of observations, to theoretical studies of cloud processes, to idealised modelling using Large Eddy Simulations and also some mesoscale modelling. Stable boundary layers featured on the first day, and the broad topic of boundary layer processes was covered throughout the week, as well as some interesting work on boundary layer clouds. Boundary layer parameterisation at all scales was covered in a few sessions, and on the fi nal day, a

session on renewable energy provided a nice preview of application-based research. Highlighted sessions from the Air-Sea Interaction conference included work on air-sea flux estimation and parameterisation, the interactions between low level winds and waves, and the effect of white caps in aerosol generation. The Air-Sea Interactions sessions covered the full range of scales, from the small, surface gravity wave scales to global climate scales. Notable contributions from international attendees included scientists from Uppsala University in Sweden, presenting their work at many sessions throughout the week, and also researchers from the University of Leeds in the United Kingdom. As part of this conference, the AMS Fofonoff Award was presented to Louis St. Laurent from Woods Hole Oceanographic Institute for his work in small scale mixing processes in the ocean. A large number of students were present at the meeting, and a prize for both best student oral presentation and best poster were up for contention for those attending the Air-Sea Interaction conference. The value of these joint conferences cannot be overstated. The current, detailed understanding of the earth system necessitates an appreciation of how all the individual components fit together. It is only through this type of interdisciplinary collaboration that we can further our knowledge of the earth system as a whole.

Call for nominations Fellows of AMOS

Nominations are called for candidates for the position of Fellow of the Society. The status of Fellow is available to a member who has made major contributions to the Society and/or the fields of meteorology or oceanography. It is expected that candidates will meet the following criteria: t Postgraduate training (diploma, masters, doctorate) in a field related to one or more of the sciences represented by AMOS. t Approximately ten years post-tertiary experience practising, applying and/or teaching one or more of the sciences represented by AMOS. t Continuous membership of the Society for a minimum of the past five years. t A substantial contribution to the work of the Society and/or the disciplines. Nominations require a proposer and seconder and should be made on the form available on the AMOS website at http://www.amos.org.au/ documents/item/22. They may either be initiated by the nominee or by the proposer/seconder (in the latter case, the signature of the nominee may be left blank and will be obtained after the form is lodged). There is no fixed deadline for Fellow nominations, but nominations to be considered for election at the 2013 AGM should be lodged no later than 30 November 2012.

Secretary

The term of the Secretary expires at the 2013 AGM. Nominations are called for election for the position of Secretary for a two-year term. Nominations must contain the names of the proposer and seconder and the consent of the candidate. Nominations close 21 days prior to the AGM (currently scheduled for 12 February 2013). All other Executive and Council terms expire at the 2014 AGM. Nominations for both Fellow and Secretary should be sent to the AMOS Administrative Officer at admin_officer@amos.org.au or GPO Box 1289, Melbourne VIC 3001.

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 79


Science Articles

Cool sea surface temperatures in the Tasman Sea associated with blocking and heat waves in Melbourne Katherine J. Sadler1, Alexandre B. Pezza1 and Wenju Cai2

School of Earth Sciences, The University of Melbourne, Parkville, Victoria CSIRO Marine and Atmospheric Research, Aspendale, Victoria. Address for correspondence: katherinejsadler@gmail.com 1 2

Katherine Sadler won the ‘best student poster’ at the recent 10th International Conferenece on Southern Hemisphere Meteorology and Oceanography in New Caledonia. She was invited to make a submission to BAMOS on her awardwinning work, which is presented in this article—Ed.

leading to death during hot weather (Nicholls et al. 2008). This study will look at summer heat waves, where summer is defined as the period from December to March. While sea surface temperatures (SSTs) are influenced by the atmosphere, blocking events influence, but may also be influenced by, the SST. Studies such as Lui and Wu (2004) and You and Ahn (2012) have investigated both of these ideas in terms of winter blocking in the Northern Hemisphere, finding that blocking does in fact influence SSTs, but SSTs do not necessarily influence blocking. Connecting these two events will reveal the underlying physical process occurring, improve our understanding of similar processes and have applications to other regions of the world.

1. Introduction It has been demonstrated that northerly winds associated with mid-latitude blocking events in the Tasman Sea play an important role in the development and maintenance of heat waves in south eastern Australia (Leighton 1994, Pezza et al. 2012). During a heat wave event, the onset of the blocking is associated with a baroclinic Rossby wave train originating in the high latitudes of the western Indian Ocean (Pezza et al. 2012). Contrary to the “perhaps” intuitive notion that heat waves are not baroclinic, it has also been shown that the evolution of the Rossby waves leading to the Tasman blocking is not dissimilar to the conditions associated with cold waves, except for a difference in phase (Ashcroft et al. 2009, Pezza et al. 2012).

2. Melbourne heat waves Heat waves are generally large scale phenomena, with widespread areas experiencing high temperatures at the same time. In this study we will focus on Melbourne due to the potential impacts on the highly populated city. The following definition was chosen to define heat waves (adapted from Pezza et al. 2012):

Heat waves are of particular concern in the summer as this is the time when the hottest temperatures of the year occur and can have impacts on the health of the general population. More vulnerable groups, such as the elderly, are at higher risk of illness and dehydration, possibly

The daily maximum temperature must exceed the 90th percentile of December–January–February–

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Figure 1: Number of summer heat waves in Melbourne per year from 1971 to 2012 using Melbourne Airport station data provided by the Bureau of Meteorology. Blue bars indicate La Niña summers, red bars indicate El Niño summers and black bars indicate neutral summers, classified using Southern Oscillation Index (SOI) data provided by the Bureau of Meteorology (www.bom.gov.au/climate/current/soihtm1.shtml). El Niño summers have an average SOI less than -8 and La Niña summers have an average SOI greater than +8 as defined by the Bureau of Meteorology. Note: events that occur in December are counted in the following year. Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 80


March (DJFM) maximum temperatures for at least three consecutive days. t

The minimum temperatures of at least two nights (after the first day of the heat wave) must exceed the 90th percentile of DJFM minimum temperatures.

Gallant and Karoly (2010) use a similar definition for hot days and nights. Temperature data provided by the Bureau of Meteorology for Melbourne Airport was used and the 90th percentile of DJFM maximum and minimum temperatures were determined to be 33.7°C and 17.5°C respectively for summer 1970/71–2011/12. Figure 1 shows the number of summer heat waves per year for 1971–2012 (note: events that occur in December are counted in the following year). There are no statistically significant trends in the number of heat waves per year over this period. Th is reflects the dominance of natural variability as well as the limited sample, with only 28 heat waves occurring between 1971 and 2012. Our sample is too small to statistically determine if heat waves are related to the El Niño-Southern Oscillation (ENSO) during the summer. Heat waves occur in both ENSO phases with more predominance during neutral summers and less predominance during El Niño summers. Interestingly, our definition counts only one heat wave during 2009 and does not include the extreme day associated with the ‘Black Saturday’ bushfires on the 7th of February, 2009. During this event the maximum temperatures for the 6th, 7th and 8th of February, 2009 were recorded as 33.5°C, 46.8°C and 20.9°C respectively. Only the maximum temperature on the 7th exceeds the 90th percentile, therefore the condition requiring 3 consecutive days with maximum temperature exceeding our threshold is not satisfied. The definition does however include the extreme heat wave, beginning on 27 January (a) i

ii

2009, that occurred just over a week before Black Saturday. While this might sound surprising, our definition is designed to capture only long lasting events that satisfy the traditional notion of “persistence”. While it efficiently portrays the most dangerous events in terms of prolonged heat exposure and immediate risk of human mortality, a full environmental assessment of previous conditions is also important when bushfire risk is involved. Persistence of dry conditions may lead up to a catastrophic event being triggered by one single day of extreme temperatures (Leighton 1994, Cai et al. 2009). Figure 2 shows composites of conditions for (i) 5 days before, (ii) the first day of and (iii) 5 days after the beginning of a heat wave in Melbourne. Temperature and mean sea level pressure are shown in (a) and outgoing longwave radiation (OLR) anomalies are shown in (b). Temperature and mean sea level pressure data come from the ERAinterim reanalysis (Dee et al. 2011) and OLR data are from the National Oceanic and Atmospheric Administration (NOAA) interpolated OLR dataset (Liebmann and Smith 1996). The high to the east of Melbourne is “semistationary” and is responsible for bringing warm inland winds from the north to Melbourne. The blocking anticyclone also brings cool, moist onshore winds to the Queensland coast causing rainfall (Sumner and Bonnell 1986) shown as negative OLR values which are indicative of tropical convection.

3. Sea surface temperatures in the Tasman Sea Figure 3 shows composites of SST anomalies for 5 days before, the first day of and 5 days after the beginning of a heat wave in Melbourne. Daily sea surface temperature data are from the NOAA optimum interpolation SST V2 dataset (Reynolds et al. 2002). Warm SST anomalies can be seen accompanying the heat wave in panel (b) showing considerable warmth where the hot winds from the °C iii

(b)

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ii

iii

Figure 2: Composite (24 cases) of (a) 2m temperature anomaly (shaded, °C) and mean sea level pressure (MSLP) (contours, hPa) and (b) outgoing longwave radiation (OLR) anomalies (Wm-2) for (i) 5 days before the start of a heat wave in Melbourne, (ii) the first day of a heat wave in Melbourne and (iii) 5 days after the start of a heat wave in Melbourne for DJFM 1979–2010 (ERA-Interim data available from 1979). Cross hatching indicates statistical significance above the 95% level for MSLP and OLR. Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 81




°C a

b

c

 Figure 3: Composite (22 cases) of sea surface temperature anomalies (°C) for (a) 5 days before the start of a heat wave in Melbourne, (b) the first day of a heat  and (c) 5 days after the start of a heat wave in Melbourne for DJFM 1981–2010. Cross hatching indicates statistical significance above the wave in Melbourne 95% level. Note: the dataset used for SSTs runs for two years less than the ERA-Interim dataset used in Figure 2.

north are blown across the water in the Great Australian Bight. Panel (c) also shows warm SST anomalies in this region remaining after the heat wave event due to the persistence of temperature anomalies in the ocean. Cool SST anomalies are present in the Tasman Sea in all three panels. The cool SST anomaly during and after a heat wave is reinforced by the subsidence and divergence of air at the surface associated with the blocking anticyclone stationed over the Tasman Sea during this time. Our hypothesis is that the cool SST anomaly in the Tasman Sea may be enhanced due to Ekman transport (to the left of the atmospheric flow) in Southern Hemisphere oceans (Price et al. 1987). The westerly winds observed to the south of the blocking high pressure system result in cool southern water being pushed northward due to Ekman transport. We argue that the cool SST anomaly that appears further north, in the Coral Sea, during the heat wave is likely to be intensified by cool south-easterly winds brought around the eastern flank of the blocking anticyclone. Hence, this would compensate any potential warming that may be

expected from the (warm) Ekman transport to the north of the anticyclone. This area is also cooled by the limited incoming solar radiation reaching the surface due to the negative OLR anomaly in this region during the heat wave (Jung et al. 2006). Figure 4 shows the evolution of the SST anomaly in the Tasman Sea (averaged over the box shown, 25–50°S, 155–170°E). The SST begins to cool around 20 days before the first day of a heat wave and the strongest negative SST anomaly coincides with the heat wave (indicated by the pink bar). Interestingly both Figures 3 and 4 indicate that there was a cool SST anomaly in the Tasman Sea from as early as 20 days before the beginning of a heat wave in Melbourne. We are interested in investigating the influence that this anomaly has (if any) on blocking in this region and hence the heat waves in Melbourne. We have designed a model experiment to test this idea where the SST anomaly will be perturbed in this region using the CSIRO Cubic Conformal Atmospheric Model (CCAM) as the next part of this project.

Average SST  anomaly  over  box  for  days  -­‐25  to  +10  of  heat  waves   Day  in  relation  to  beginning  of  a  heat  wave   ͲϮϱ ͲϮϰ ͲϮϯ ͲϮϮ ͲϮϭ ͲϮϬ Ͳϭϵ Ͳϭϴ Ͳϭϳ Ͳϭϲ Ͳϭϱ Ͳϭϰ Ͳϭϯ ͲϭϮ Ͳϭϭ ͲϭϬ Ͳϵ Ͳϴ Ͳϳ Ͳϲ Ͳϱ Ͳϰ Ͳϯ ͲϮ Ͳϭ Ϭ ϭ Ϯ ϯ ϰ ϱ ϲ ϳ ϴ ϵ ϭϬ

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Figure 4: Average sea surface temperature anomaly taken over the box (inset) defined as 25–50°S, 155–170°E for composites (22 cases) of 25 days before the start of a heat wave to 10 days after the start of a heat wave for DJFM 1981–2010. The transparent pink bar indicates when a heat wave is occurring according to our definition (see Section 2). Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 82


Other studies have also used models to investigate the influence of SST on blocking, such as Lui and Wu (2004) and You and Ahn (2012). These studies generally look at winter blocking in the Northern Hemisphere and impose warm SST anomalies in the Pacific Ocean as this is present in averages of winters with a high frequency of blocking. Lui and Wu (2004) find that there may be a relationship between SST and blocking through surface heat fluxes. You and Ahn (2012) fi nd little influence of warm SST anomalies on blocking. In another experiment they find that when cool SST anomalies were imposed there was an increase in the seasonal average of their measure of blocking, 500hPa geopotential height, in the region.

4. Conclusions There is no statistically significant trend in number of heat waves in Melbourne between 1971 and 2012. There is a large interannual variability in the number of heat waves per year. On the first day of a heat wave a large blocking high is present in the Tasman Sea bringing warm air from the north and cool moist air onshore along the Queensland coast. Cool SST anomalies during and after the heat wave are reinforced by the anticyclonic circulation. Cool SST anomalies in the Tasman Sea before the heat wave may be creating favourable conditions for blocking formation.

5. Further Work The CSIRO CCAM model will be used to investigate the sea surface temperature impacts on atmospheric blocking and rainfall by perturbing the sea surface temperature in the Tasman and Coral Seas. The Lorenz energetics associated with blocking anticyclones will also be investigated, to study the environmental energy transfers associated with blocking maintenance.

Acknowledgements We thank Kevin Walsh for reading an earlier version of our manuscript. Alexandre B. Pezza is grateful to the Australian Research Council for supporting parts of this work. We also thank Marcus Thatcher from CSIRO for the research support and discussion related to future work.

References Ashcroft, L.C., Pezza, A.B. and Simmonds, I., 2009, Cold events over Southern Australia: Synoptic climatology and hemispheric structure, Journal of Climate, 22, 6679–6698. Cai, W., Cowan, T. and Raupach, M., 2009, Positive Indian Ocean Dipole events precondition southeast Australia

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 83

bushfires, Geophysical Research Letters, 36, L19710, doi:10.1029/2009GL039902. Dee, D.P. and Coauthors, 2011, The ERA-Interim Reanalysis: Configuration and performance of the data assimilation system, Quarterly Journal of the Royal Meteorological Society, 137, 553–597. Gallant, A. and Karoly, D., 2010, A combined climate extremes index for the Australian region, Journal of Climate, 23, 6153–6165. Jung, T., Ferranti, L. and Tompkins, A.M., 2006, Response to the summer of 2003 Mediterranean SST anomalies over Europe and Africa, Journal of Climate, 19, 5439–5454. Liebmann, B. and Smith, C.A., 1996, Description of a complete (interpolated) outgoing longwave radiation dataset, Bulletin of the American Meteorological Society, 77, 1275–1277. Leighton, R.M., 1994, Relationship of anomalies of (anti) cyclonicity to some significant weather events over the Australian region, Australian Meteorological Magazine, 43, 255–261. Lui, Z. and Wu, L., 2004, Atmospheric response to the North Pacific SST; The role of ocean-atmosphere coupling, Journal of Climate, 17, 1859–1882. Nicholls, N., Skinner, C. and Loughnan, M., 2008, A simple heat alert system for Melbourne, Australia, International Journal of Biometeorology, 52, 375–384. Pezza, A.B., van Rensch, P. and Cai, W., 2012, Severe heat waves in southern Australia: Synoptic climatology and large scale connections, Climate Dynamics, 38, 209–224. Price, J.F., Schudlich, R.R. and Weller, R.A., 1987, Winddriven ocean currents and Ekman transport, Science, 238, 1534–1538. Reynolds, R.W., Rayner, N.A., Smith, T.M., Stokes, D.C. and Wang, W., 2002, An improved in situ and satellite SST analysis for climate, Journal of Climate, 15, 1609–1625. Sumner, G. and Bonnell, M., 1986, Circulation and daily rainfall in the North Queensland wet seasons 1979–1982, Journal of Climatology, 6, 531–549. You, J. and Ahn, J., 2012, The anomalous structures of atmospheric and oceanic variables associated with the frequency of North Pacific winter blocking, Journal of Geophysical Research, 117, L11108, doi:10.1029/2012JD017431.


Meet a Member

Andrea Taschetto Where does this find you? I am at home, after having a nice pasta for dinner and putting my little son into bed. What do you do? I am a researcher at the Climate Change Research Centre, University of New South Wales (UNSW), Sydney. I have been studying the climate impacts over different regions across the globe linked to variations in ocean temperature. More specifically, I am interested on the effects of sea surface temperature conditions in the tropical Pacific (e.g. El Ni単o) and Indian Oceans onto Australian and South American rainfall. Why did you get into it? Since I was little, my head has always been in the clouds. This might have been the first sign that I am inclined to atmospheric sciences, although I only realised that once I was at university. I created special feelings for climate science when I was an undergraduate student at the University of Sao Paulo, Brazil, and had contact with the field via an internship program. By the end of my Bachelor degree in physics I decided to get into research, so I spent another few years doing my MSc and PhD in physical oceanography before becoming a climate researcher. In the last year of my PhD program, I decided to move to another university to enrich my knowledge, get new experience, and meet some famous names that appear in scientific journals. At that time, there were a few postdoc positions open at UNSW, Sydney, with Prof. Matthew England, so I applied for one of them. Australia was a country that I had always wanted to visit. Eventually I got the job and I have been working on what I like and in a perfect location since 2006. What is the best thing about what you do? The best thing about my work is its contribution to the advance of science, even when the contribution seems little. Looking from my egocentric point of view, I also love learning new things and I enjoy the freedom of choosing the topics to be researched, the fl exibility of work hours (although this sometimes leads to many more hours of work), the possibility of working from home, and the opportunity of travelling for international meetings. What did you want to be when you were 10? When I was young I wanted to be a doctor, more specifically a paediatrician. But by my adolescence, I realised that I liked not only medicine, but also many types of sciences from mathematics to genetics.

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 84

New South Wales member Andrea Taschetto. Image: Andrea Taschetto How do you relax? Sleeping. I used to relax reading a good book or watching a nice movie. Since my son was born, my relaxing time is to spend as much time as possible with him. What is your favourite holiday destination? I love visiting new places, experiencing new cultures and meeting new people. I have an extensive list of trips I wish to do one day, e.g. a backpack tour around Europe and southeast Asia. But I have already had wonderful travel experiences in my life. Some of those moments are registered in my memory forever, such as my adventurous bungy-jump in New Zealand; ridiculous attempts to communicate on the streets of Beijing, China; the colourful tulips during spring in Holland; romantic time with my husband in Paris; exotic species of birds and other animals in Pantanal, Brazil; unforgettable snorkelling in New Caledonia; beautiful beaches of Corsica, and impressive architecture of Budapest and Vienna.


Snapshot

Early spring thunderstorm 23 August 2012 Duncan Ackerley

This image shows the base of a cumulonimbus line and rainfall associated with a pre-frontal trough that passed through Melbourne on 23 August 2012. The snapshot was taken at approximately 4 p.m. looking west from the top level of the Monash University multi-storey car park. The Bureau of Meteorology issued a severe weather warning for the line of thunderstorms, which were the fi rst of the (almost) spring in Melbourne. Numerous lightning flashes were associated with the line of convection and small hail fell as the main line passed over the School of

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 85

Mathematics at Monash University. This photograph was taken as the time between flashes of lightning and thunder had reduced to approximately 5–10 seconds. By this point, the Editor and a couple of other work-colleagues quickly returned to the department to take shelter. Th is photo shows some of the precipitation associated with the convection and the strong turbulence under the clouds. If you have an image of the weather near you to share, send it to duncan.ackerley@monash.edu, or post it on the AMOS Facebook page. — Ed.


Charts from the Past with Blair Trewin

8 August 1955 Major westerly wind events were not an uncommon feature in southern Australia in the 1950s. One of the more notable events occurred in early August 1955, as a result of an intense low pressure system near Tasmania. The fi rst region to be badly impacted by severe winds was South Australia, which was hit over the weekend 6–7 August. Wind damage and power outages were widespread in the Adelaide region, with gusts to 108 km/h at Adelaide Airport. Flooding also occurred from rainfall in rivers draining the Adelaide Hills, and from storm surges in the State’s southeast, which also had frequent hail showers. The Kingston Jetty was badly damaged and numerous boats broke their moorings. By the 8th, the focus of the severe weather had moved further east. Hobart measured its lowest sea level pressure on record (965.9 hPa), and Melbourne, where the pressure stayed below 990 hPa for nearly two days, set an August record of 983.8 hPa. Wind gusts reached 121 km/h at Geelong and 105 km/h at Melbourne (an August record). Whilst there was wind damage on land at Melbourne, the most significant impact was through storm surge and waves on the eastern side of Port Phillip. “Hundreds” of small craft moored in the bay were sunk or dashed ashore, and many shoreline bathing boxes were damaged as beaches were badly eroded. The freighter River Burnett was grounded off Mt. Eliza. In Tasmania, the most significant wind damage was in the north, particularly on King Island where the old wharf and church tower at Currie were destroyed. The winds also affected southern New South Wales, fuelling a number of bushfires in the

Sydney area. The next day, a suspected tornado caused damage at Portland in southwestern Victoria. Rainfall was concentrated on, and upstream of, the ranges, particularly in the Alps and north-western Tasmania. Notable falls on the 8th included 90 mm at Bogong and 79 mm at Harrietville in Victoria, and 71 mm at Sheffield in Tasmania, whilst falls of 20 mm or above covered most of the Victorian ranges, northwestern Tasmania, VictoriaSA border regions and the Adelaide Hills. There was some flooding, mostly in rivers draining the north side of the ranges. However, areas sheltered from westerlies only had light falls; Hobart had 9 mm in the four days 7–10 August, and Melbourne 5 mm. Although the event was not exceptional for cold, temperatures still fell below normal once winds turned to the southwest, with Canberra having five consecutive days below 10°C. Snow fell briefly in the higher parts of the Dandenongs and around Kyneton. At higher altitudes, it was a major snow event; Kiandra was cut off for several days after what were reported as the “worst blizzards in 20 years”. Conditions moderated only slowly and severe winds did not clear south-eastern Australia altogether until the 13th. Further rains in the following weeks gave Victoria its third-wettest August on record, whilst the persistent westerlies also contributed to an exceptionally wet August in southwest Western Australia, where it was the region’s wettest August on record by a large margin. Perth had 29 rain days during the month.

Synoptic chart for 0600 AEST 8 August 1955

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 86


Calendar

2012

February

October 22–25 NOAA’s 37th Climate Diagnostics and Prediction Workshop, Colorado, USA.

November

11–13 19th Annual AMOS Conference, “Sense and sensitivity: Understanding our changing climate,” Melbourne.

April 7–12 EGU General Assembly 2013, Vienna, Austria.

5–8 AMS 26 Conference on Severe Local Storms, Nashville, Tennessee, USA

15–19 4th WGNE workshop on systematic errors in weather and climate models, Met Office, Exeter, UK.

12–15 CAWCR Annual Workshop, Melbourne.

June

th

19–20 New Zealand MetSoc. Annual conference, Wellington, New Zealand.

December 3–4 Annual International Conference on Geological & Earth Sciences (GEOS 2012), Hotel Fort Canning, Singapore. 3–7 AGU 2012 Fall Meeting, San Francisco, California, USA.

17–21 AMS, 19th Conference on Atmospheric and Oceanic Fluid Dynamics, Newport, Rhode Island, USA. 17–21 AMS, 17th Conference on the Middle Atmosphere, Newport, Rhode Island, USA. 24–28 19th International Conference on Nucleation and Atmospheric Aerosols Fort Collins, CO, USA (website and 1st Circular in preparation).

2013 January 6–10 93rd AMS Annual Meeting, “Taking Predictions to the Next Level: Expanding Beyond Today’s Weather, Water, and Climate Forecasting and Projections.” Austin, Texas, USA.

Australian Meteorological and Oceanographic Journal

Articles — Vol 62 No. 2, June 2012 Greenslade. The optimal placement of tsunameters in the Tasman Sea. Garces-Vargas, and Abarca-del-Rio. The surface heat fluxes along the eastern Pacific coast from 10°N to 40°S. Marinelli, Braganza, Collins, Jones, Maguire, and Cook. Defining a high-quality daily rainfall candidate network for Western Australia Nicholls. Is Australia’s continued warming caused by drought?

Bulletin of the Australian Meteorological and Oceanographic Society Vol.25 page 87

Regular features: Tobin. Seasonal climate summary southern hemisphere (winter 2011): a dry season in the lull between La Niña events. Wu. Quarterly numerical weather prediction model performance summary — January to March 2012.


2012 AMOS Council Executive

President Vice-President Secretary Treasurer Past President

Blair Trewin Todd Lane Damien Irving Ian Watterson Neville Nicholls

Ordinary Members John Allen Andrew Klekociuk Robin Roberston Sandra Schuster Richard Wardle Perry Wiles

03-8344 9596 03-6232 3382 02-6268 8289 02-9272 8025 03-9905 4411 03-9669 4664

AMOS Administrative Officer

Jeanette Dargaville GPO Box 1289, Melbourne VIC 3001 (attn: AMOS admin officer) Phone 0404 471 143 E-mail: admin_officer@amos.org.au

03-9669 4623 03-8344 6516 03-9239 4685 03-9239 4544 03-9902 0111

Sub-Committee Convenors Public Relations Awards 2013 Conference Education Membership

Centre Chairs NSW Hobart Melbourne ACT Perth Darwin Brisbane Adelaide

Vacant Mark Williams Vaughan Barras Phillip Riley Michael Hewson

0419 519 440 03-9669 4045 03-9669 4530 0408 379 373

Steven Phipps Kelvin Michael Damien Irving Clem Davis Merv Lynch Hakeem Shaik Hamish McGowan Andrew MacKinnon

02-9385 8957 03-6226 2977 03-8344 6911 02-6254 2861 08-9266 7540 08-8920 3814 07-3365 6651 08-8313 3875

Representatives AMOJ Science & Technology Australia

David Karoly

03-8344 4698

Steven Phipps

02-9385 8957

AMOS is represented on the relevant Australian Academy of Science committees.

2012 Bulletin of the Australian Meteorological and Oceanographic Society ISSN 1035-6576

Editor

Duncan Ackerley Monash Weather and Climate School of Mathematical Sciences Monash University VIC 3800 Phone: 03-9902 4900 Fax: 03-9005 4403 Email:duncan.ackerley@monash.edu

Editor-in-chief

Stewart Allen Email: Stewart.Allen@bom.gov.au

Assistant Editors Diana Greenslade Blair Trewin Linden Ashcroft

Regional Sub-editors

Michael Hewson (Brisbane) Caecilia Ewenz (Adelaide) Nicholas Tyrrell and Luke Hande (Melbourne) Fiona Johnson (NSW) Clem Davis (ACT)

Contributors Blair Trewin

Advertising Manager Please contact the Admin. Officer.

Publisher

AMOS, GPO Box 1289, Melbourne VIC 3001, Australia

Contributed articles, news, announcements and correspondence for the Bulletin should be sent to the editor no later than 23 November 2012. 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 Website: www.amos.org.au


Bulletin vol 25 no 5 oct 2012  
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