Seminars - Melbourne

CAWCR SEMINARS 2010

Date Time Title Speaker Affiliation
Friday 17th September 2010 10:00am Modelling fire weather interactions (tbc) Janice Coen NCAR
Thursday 19th August 2010 10:00am CO2 observations from space - status and plans Peter Rayner Univ Melbourne
Thursday 12th August 2010 10:00am Down-selection of NWP ensemble configurations Jared Lee Penn State Univ
Wednesday 11th August 2010 10:00am 4D-VAR for dummies Jeff Kepert CAWCR
Tuesday 10th August 2010 11:00am Modelling of climate and climate variability John You Univ Syndey
Thursday 29th July 2010 10:00am The impact of assimilating radar estimated precipitation rates on simulations of the July 17-18 Chicago flood Xingbao Wang CAWCR
Monday 26th July 2010 2:00pm Victorian Centre for Climate Change Adaptation Research Rod Keenan Univ Melbourne
Thursday 8th July 2010 10:00am Multiscale climate simulation over southern Africa using CCAM Francois Engelbrecht CSIRNRE
Thursday 17th June 2010 2:00pm The Southern Annular Mode and its influence on Australian intra-seasonal climate in POAMA Andrew Marshall CSIRO Hobart
Wednesday 9th June 2010 10:00am Sydney airport wind shear study Rod Potts CAWCR
Thursday 3rd June 2010 2:00pm Petascale technology opportunities and challenges for Earth System Modelling Per Nyberg Cray
Friday 28th May 2010 10:00am New techniques and software package for detection and adjustment of shifts in daily precipitation data series Xiaolan Wang Environment Canada
Thursday 27th May 2010 10:00am Extreme value analysis and projection in light of the changing climate Xiaolan Wang Environment Canada
Monday 17th May 2010 2:30pm Clear-sky retrieval biases in the Pathfinder SST record Andy Harris Univ Maryland
Monday 17th May 2010 2:00pm The calibration of broad band infrared sensors – errors, biases and a way forward Jon Mittaz Univ Maryland
Friday 14th May 2010 10:00am Soil moisture under Climate change at Talaheni John Ive 'Talaheni', ACT
Thursday 6th May 2010 10:00am Probability Forecasting, Probability Evaluation, and Scoring Rules: Expanding the Toolbox Bob Winkler Duke University
Wednesday 5th May 2010 10:00am Short-to-medium term predictability issues in the tropics Kamal Puri CAWCR BoM
Friday 23rd Apr 2010 10:00am Where emission inventories, observational networks and emissions models meet; a background to accounting in the era of emissions regulation Mick Meyer CAWCR Aspendale
Tuesday 20th Apr 2010 10:00am Boundary layer processes in ACCESS - parameterisations, problems and progress Vaughan Barras CAWCR BoM
Tuesday 13th Apr 2010 10:00am "Verify" and Gridded Forecast Verification at the Bureau Claude Gibert, Chris Bridge GMAO, NMOC
Wednesday 7th Apr 2010 10:00am The changing climate research agenda Chris Gordon UKMO Hadley Centre
Friday 19th Mar 2010 10:00am The non-existence of the Indian Ocean Dipole (IOD) Mode Dietmar Dommenget Monash University
Thursday 11th Mar 2010 2:30pm A retrospective of my years in the Bureau, 1959-2009 Robert Seaman CAWCR (ret.)
Friday 19th Feb 2010 10:00am Exploiting long-term wind and solar observations to inform the energy industry Alberto Troccoli CSIRO
Tuesday 9th Feb 2010 10:00am CO2, ancient climates and the 20-21st century shift in the state of the atmosphere Andrew Glikson ANU

The venue is the seminar room (Floor 9, east side) at 700 Collins Street, Docklands

Seminars are run typically with duration of 30 to 50 minutes + questions. Dates and times are shown. If you are a vistor to the Bureau, you need to register at reception in the foyer.

Emphasis is on work in progress. Partly because of this, the schedule is susceptible to change.
To receive this information via email, simply send an email to majordomo@bom.gov.au containing the single line in the body of the message: subscribe bmrc_seminars . If you want to stop receiving the email use: unsubscribe bmrc_seminars .

A PDF copy of all the presented seminars can be found at the "Find Seminar Presentation Documents..." link at the top of the page (available to BoM staff only). Seminars for previous years can be found at the "Goto list of BMRC seminars for ..." site at the top of the page. In addition, a list of actual videos from some previous seminars is held in the library and can be found on the catalogue by entering Series: BMRC, Format: Video. If you would like to have a talk videotaped please contact the seminar coordinator. Note: as of 2005, it is standard practice for all seminars to be recorded as wmv movies, provided the presenter agrees.

If you would like to know more details of coordinating seminars (if, for example, you are hosting a visitor who will be giving a seminar and the regular seminar coordinator is not available), have a look at the document, "Instructions for CAWCR Seminar Coordinator"

For further details contact the seminar coordinator, Vaughan Barras, on 03 9669 4045, email


ABSTRACTS

Tuesday 9th February, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

CO2, ancient climates and the 20-21st century shift in the state of the atmosphere

Andrew Glikson

Australian National University
Canberra, ACT

The dominant greenhouse state of the atmosphere on the early Earth, interrupted by glacial periods at ~2.4-2.2 Ga and ~0.75-0.65 Ga (Snowball Earth, terminated by a build-up of CO2), Cambrian ~0.53 Ga, Ordovician ~0.44 Ga, late Devonian ~0.36 Ga, Permian ~0.33-0.27 Ga, minor Jurassic and Cretaceous glaciations, and the post-34 Ma glacial-interglacial state. The emergence of land vegetation in the late Silurian (~0.42 Ga), enhanced photosynthesis and weathering-related CO2-sequestration led to atmospheric oxygen enhancement through organic processing of CO2 and removal/burial of carbon. Mass extinctions of species at the end of the Devonian, Permian, Triassic and Cretaceous were associated with the effects of large asteroid impacts and volcanic events, triggering atmospheric CO2 and CH4 spikes and ocean acidification. Greenhouse events at 55 Ma, 15 Ma, and 2.8 Ma associated with peak atmospheric temperatures allow estimates of climate sensitivity under both greenhouse and glacial-interglacial Earth conditions. These include (1) Paleocene-Eocene thermal maximum (~55 Ma: escape of ~2000 GtC as methane, CO2 rise from 400 to 800 ppm, T rise ~ +5C; (2) Mid-Miocene (CO2 rise from ~280 to ~520 ppm; T rise ~ +2.4C), suggesting a climate sensitivity of about 2.8oC per-doubling of CO2 (CS); (3) mid-Pliocene (CO2 rise to ~400 ppm and T rise ~2C to 3C). Estimates based on the last glacial termination (180-280 ppm CO2; T ~ +4.5C) yield high CS value of ~6 to 8C associated with an ice melt feedback loop ahead of CO2 rise. Climate sensitivity estimates from the 18th century (for CO2 rise of 280 to 388 ppm and mean global temperature rise of +0.8oC plus ~ +0.5oC currently masked by sulphur aerosols) yields CS value of ~3.4 oC, not accounting for the effects of current albedo loss due to melting cryosphere and methane release from permafrost and bogs.

Figure 1 (pdf)

Friday 19th February, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Exploiting long-term wind and solar observations to inform the energy industry

Alberto Troccoli

CSIRO

A large network of approximately 500 stations for wind observations is available over Australia. Some records go as far back as the 1920s, with a large proportion starting in the 1950s. However, as found by Muirhead (2000) and Jakob (2010) there are several issues to be considered when analysing these data. Here the objective is to investigate the relationships between the main climate modes in Australia - ENSO and IOD - and the interannual variations in wind energy. Such relationships would provide the potential for improving the planning and operation of wind farms in Australia from the wind-power and economic viewpoints. However, before delving into these relationships, a careful selection of the data had to be carried out. The factors taken into account include location, proximity to obstructions, length of continuous data record, and data quality (removing the sudden steps in the data caused by changes in instrumentation, etc.). Preliminary results in the relationship between ENSO and station wind observations are discussed. An analogous investigation is also undertaken using the less abundant and shorter array of solar radiation observations. Reanalysis data are also examined in order to provide a more robust analysis.

References:
Jakob D (2010) "Challenges in developing a high-quality wind data set for Australia", to be submitted to Aust. Met. Mag.

Muirhead I (2000) "Applications for Climate Data in Renewable Energy" Proceedings of the ANZSES Solar 2000 Conference, 29 Nov - 1 Dec 2000, Brisbane, Australia.


Thursday 11th March, 2:30pm - 3:30pm, Conference Rooms 1 & 2, 6th floor, 700 Collins St

A retrospective of my years in the Bureau, 1959-2009

Robert Seaman

CAWCR (ret.)

"The past is a foreign country; they do things differently there."

I shall cover the period from 1959 to 2009, from the perspective of where I was in the Bureau at the time. The talk will be mainly impressionistic. There won't be much detailed science, and I promise no equations or fancy powerpoint graphics. My overheads will be mainly dot points for each period, and quotes. I shall mention a few of the people I have encountered along the way who have influenced me substantially. I shall also try to summarise some of the lessons I have learnt.

PDF copy of slides  ||  WMV presentation  ||  Photos



Friday 19th March, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

The non-existence of the Indian Ocean Dipole (IOD) Mode

Dietmar Dommenget

Monash University

Current research of Indian Ocean SST variability focus on the tropical Indian Ocean Dipole (IOD) Mode, which were motivated by the Saji et al. [1999] and Webster [1999] articles about an IOD Mode independent of ENSO. The presentation will critically discuss the evidence for the IOD mode based on three different arguments:
1) Objective analysis of the spatial structure of Indian Ocean SST variability.
2) The conceptual Bjerknes feedbacks are analysed in the context of the ENSO recharge oscillator.
3) Predictability of Indian Ocean SST indices are study in state of the art coupled general circulation forecast systems and in a simple statistical model forced with ENSO.
The talk will conclude with a description of the truly important structures of Indian Ocean SST modes.


Wednesday 7th April, 11:00am - 12:00pm, Conference/Meeting Rooms, 9th floor east, 700 Collins St

The changing climate research agenda

Chris Gordon

UKMO Hadley Centre

Over the last few years, the requirement for information to underpin climate change adaptation policies has increased considerably. One example was the recognition at last year’s World Climate Conference-3 of the need for a Global Framework for Climate Services. This poses a considerable challenge to climate science. Reliable information is needed regionally and locally and on timescales of a few years to a century ahead. In particular, over the coming few decades the level of climate change is largely unavoidable and will be primarily felt when climate change and variability signals are in phase, leading to an enhancement of extreme climatic conditions. This talk will focus on recent research from the Met Office Hadley Centre, giving examples of how we are beginning to address some of these new challenges.


Tuesday 13th April, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

"Verify" and gridded forecast verification at the Bureau

Claude Gibert1
Chris Bridge2

1 GMAO
2 NMOC

A project in underway at the Bureau to implement a common verification system for gridded forecasts. The basis for this system is a Python-based software-package called "Verify". The aim of this presentation is to raise awareness of Verify within the Bureau and, consequently, to stimulate interest within the organisation for this software as a valuable forecast verification tool. Claude Gibert, formerly at ECMWF and now at NASA’s Global Modeling and Assimilation Office, is the principle author of this software and will provide an introduction to Verify. Chris Bridge, who has been implementing and customising Verify at the Bureau, will then describe the progress of the project which, to date, has focussed on replicating NMOC’s current operational verification suite. Likely directions for future development will also be outlined.


Tuesday 20th April, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Boundary layer processes in ACCESS - parameterisations, problems and progress

Vaughan Barras

CAWCR BoM

The accurate representation of the planetary boundary layer (PBL) in numerical models is important in the calculation of surface energy exchange, radiative processes. The UK Met Office Unified Model (UM) forms the atmospheric component of the Australian Community Climate and Earth System Simulator (ACCESS). The UM uses a first order K-diffusion parameterisation for the representation of turbulent fluxes as described by Lock et al. (2000). The vertical profile of the K coefficients for momentum and scalar quantities is determined by assigning the PBL at a particular location to one of seven stability categories. Stable processes (type 1) follow a Louis type scheme where the diffusion coefficients are highly reliant upon the value of the Richardson Number. Unstable conditions are diagnosed by a 'top-down, bottom-up' parcel release method to determine the vertical extent of turbulent exchange by surface-driven and entrainment layer processes.

The general features of the UM boundary layer scheme will be presented along with results from experiments conducted by the CAWCR PBL model development team testing the implementation of a new parameterisation of 10 metre wind speeds under strongly stable conditions. In addition, recent work addressing issues arising in the operational NWP system will be briefly discussed.


Friday 23rd April, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Where emission inventories, observational networks and emissions models meet; a background to accounting in the era of emissions regulation

Mick Meyer

CAWCR Aspendale

Emissions inventories and emissions accounting methodologies are becoming key components of National and International agreements aimed at controlling aspects of air quality. Notable examples are the IPCC Greenhouse Gas Inventory methodology that underpins the UNFCCC and the UNEP toolkit that supports the Stockholm Convention on Persistent Organic Pollutants. Inventory science continues to advance from quantification of emission processes and activities at an industry level, to spatial modelling across landscapes and verification of emission estimates against atmospheric observations. During the last few years smoke from biomass combustion has emerged as a major issue for air quality and health and climate science. This presentation discusses current international accounting approaches for bushfire smoke emissions, and how remote sensing, observation networks and dispersion modelling are being used to improve and verify regional emission estimates.


Wednesday 5th May, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Short-to-medium term predictability issues in the tropics

Kamal Puri

CAWCR BoM

In a key paper Shukla (Predictability of the Tropical Atmosphere, 1981) concluded that (i) the theoretical upper limit of deterministic predictability for low latitudes is shorter than for middle latitudes, (ii) most of day-to-day fluctuations in the tropics are determined by the growth and decay of condensation driven instabilities for which the amplitudes equilibrate rapidly, (iii) it takes only a few days for an initial error to grow to a magnitude comparable to the climatological variance, (iv) variability of time averages in low latitudes is largely influenced by the slowly varying boundary conditions of SST and soil moisture and (v) since synoptic instabilities are not strong enough to change drastically the large scale flow, there is larger potential for predictability of monthly and seasonal means in low latitudes. An implication of these results was that day-to-day predictability in the tropics might be low. This presentation will present results/scores to give an indication of the current status of tropical numerical weather prediction, some of the key remaining issues and try and interpret these in light of Shukla's results.


Thursday 6th May, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Probability Forecasting, Probability Evaluation, and Scoring Rules: Expanding the Toolbox

Bob Winkler

Duke University

Bayesian methods are inherently probabilistic, with uncertainty explicitly represented in terms of probabilities. In the subjective Bayesian framework, these probabilities are ultimately personal, whether they represent judgmental forecasts or forecasts based on models chosen by an analyst. This raises questions about the incentives for 'good' probability forecasts and for the evaluation of probability forecasts in light of the events that occur. Scoring rules were developed to provide both ex ante incentives for careful and truthful probability forecasts and ex post evaluation measures that investigate characteristics of probability forecasts and can identify 'better' probability forecasters. This talk focuses on recent developments in scoring rules that enrich the set of available rules and raise some important probability forecasting and evaluation issues deserving of further attention.


Friday 14th May, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Soil moisture under Climate change at Talaheni

John Ive

'Talaheni', ACT

John Ive is the manager of 'Talaheni' a 245-hectare property in Yass Valley, this property suffered from severe dryland salinity, soil acidity and associated vegetation decline. At Talaheni, John has measure the depth to the water table at 12 piezometers monitored weekly for nearly 20 years. This has provided him with a long term perspective of his property’s soil moisture. With a program he developed called Waterbank, John has conducted comprehensive modelling, initially using the observed meteorological records for the same period. He then used temperature and rainfall projections from the IPCC AR4 models downscaled to the nearest Bureau of Meteorology high quality network location: Yass. Waterbank was used with the downscaled projections to create future projections of soil moisture for two 20 year period in the middle and the end of the 21st century. From this analysis, John has obtained guidance for the long-term management of his property. More details at: http://www.dpi.nsw.gov.au/aboutus/news/agriculture-today/december-2009/more-time-at-or-below-wilting-point


Monday 17th May, 2:00pm - 2:30pm, Conference Room 3, 6th floor, 700 Collins St

The calibration of broad band infrared sensors - errors, biases and a way forward

Jon Mittaz

Univerisity of Maryland

Central to obtaining accurate estimates of geophysical parameters from broadband infrared sensors are accurate and well-characterized brightness temperatures that in turn require an accurate instrument calibration. To date, however, many of the commonly used sensors have calibration schemes that have been found to introduce large (>0.5K) biases into the data. Such large biases are known to exist in two of the major broadband IR sensors, the AVHRR and GOES, and the size of these biases and their temperature and/or time dependent behaviour will be shown. The implication to the calibration of MTSAT-2 (a GOES like sensor which is due to go operational on the 1st July this year) will also be discussed. A new calibration scheme will then be described which is capable of determining the underlying cause for the biases seen in each sensor and can be used to fix the calibration. Remaining issues and the generation of a new climate data record based on a re-calibration of the complete AVHRR data record to be used for climate studies will then be discussed.


Monday 17th May, 2:30pm - 3:00pm, Conference Room 3, 6th floor, 700 Collins St

Clear-sky retrieval biases in the Pathfinder SST record

Andy Harris

Univerisity of Maryland

Comprehensive modeling studies have been carried out to simulate the expected clear-sky SST retrieval error in the AVHRR Pathfinder dataset. The resultant SST retrieval bias estimates, derived from over 150 million atmospheric simulations, are evaluated and display similarities to those observed in the actual record. The retrieval biases are investigated to determine the underlying physical causes, including the effects of air-sea temperature difference and atmospheric absorption. The observed annual signal in bias is shown to largely be a function of the underlying SST retrieval algorithm form, and is likely to have an impact on the determination of Empirical Orthogonal Functions for historical SST reconstruction techniques.


Thursday 27th May, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Extreme Value Analysis and Projection in Light of the Changing Climate

Xiaolan Wang

Environment Canada

The Earth's climate is changing. Extremes of the changing climate are most likely those of a non-stationary process, which will have characteristics that change systematically through time. In this case, the classical stationary extreme value (EV) models, with constant parameters, are no longer appropriate. One should allow the EV model parameters to change through time in order to represent the systematically changing characteristics of extremes. This can be done by letting all or some of the EV model parameters to vary with covariates. Depending on the purpose of analysis, the covariates can be predictor-variables of the extremes, or functions of time itself.

In this presentation, I will first talk about the stationary generalized extreme value model for block maxima (e.g., annual maxima), the stationary generalized Pareto distribution model for peaks-over-threshold, and the latest developments in estimating parameters of these EV models and in testing the goodness-of-fit. Then, I will talk about EV models with covariates, when to use what covariates (predictor-variables or time itself), and how to use these models to (1) analyze trends in climate extremes and (2) make projections of extremes that correspond to a possible future climate projected by climate models. I will show examples of fitting stationary EV models, and of using an EV model with covariates to analyze trends in extremes and to project possible future changes in extremes. My examples include extremes of Australian geostrophic wind speeds (a storminess index), of Canadian daily temperatures, and of global ocean wave heights.


Friday 28th May, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

New techniques and software package for detection and adjustment of shifts in daily precipitation data series

Xiaolan Wang

Environment Canada

In this presentation, I will first briefly introduce the data homogenization techniques and software package that we have developed in the past few years, namely the PMT and PMF tests, the PMTred and PMFred algorithms, and the RHtestsV3 software package. The RHtestsV3 functions are developed for data series whose random component well approximates a Gaussian distribution, without or with some data transformation (e.g., a log transformation for monthly total precipitation series). They are not directly applicable to daily precipitation series, which are non-negative and typically non-Gaussian. However, homogenization of daily precipitation series is particularly important for characterizing trends in precipitation extremes. Thus, this presentation will focus on how we integrate a Box-Cox transformation procedure into the PMFred algorithm, to make it applicable to non-zero daily precipitation amounts (or non-Gaussian positive data in general), and on the new quantile-matching (QM) algorithm for adjusting for artificial shifts that affect not only the mean of the data series. Our simulation study shows that the resulting new algorithm is much better than the corresponding untransformed method for non-Gaussian data series; it can increase the hit rate by up to about 70%. I will also briefly introduce the RHtests_dlyPrcp package that we have developed for homogenization of daily precipitation data series. I will show examples of application of this new algorithm to detect shifts in real daily precipitation series recorded at stations of various precipitation regimes. Since precipitation is not a continuous variable, discontinuities could exist in the series of its occurrence frequency or of the measured amounts, or both. I will also talk about frequency discontinuities in daily precipitation data series, how they could complicate detection and adjustments of shifts, and how to detect and deal with them for purpose of daily precipitation data homogenization.


Thursday 3rd June, 2:00pm - 3:30pm, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Petascale technology opportunities and challenges for Earth System Modelling

Per Nyberg

Cray

Securing the highest possible performance capabilities is a key requirement in advancing the state of the earth system modelling community. The continued growth in system size creates both opportunities for the advancement of simulation capabilities and challenges for the HPC community. While the prospect of exascale systems brings even greater potential for advanced simulations, the Earth System Modelling community has identified several key limiting factors that must be addressed. Success will depend on the convergence of multiple disciplines and stakeholders.

Cray is proud to be a partner with a number of leadership centres worldwide that are at the forefront of delivering production supercomputing today and laying the groundwork for further extreme scale facilities in the years to come. The Oak Ridge National Laboratory (ORNL) 'Jaguar' and U.S. National Science Foundation / University of Tennessee 'Kraken' petascale Cray XT5 systems have been key milestones in this process and represented a major leap forward for the earth system modelling community. In addition, Cray recently announced that the U.S. National Oceanic and Atmospheric Administration (NOAA) and ORNL will be installing the world's largest supercomputer dedicated to climate research later this year followed by an upgrade in 2011. Further recent announcements include the Korea Meteorological Administration and the Brazilian Centre for Weather Forecasts and Climate Studies (CPTEC).

This presentation will cover recent updates from Cray, activities in the earth system modelling community and perspectives on high performance computing over the next few years.


Wednesday 9th June, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Sydney airport wind shear study

Rod Potts1*
Bill Mahoney2

1 CAWCR BoM
2 NCAR

On 15 April 2007, a Boeing 747 encountered a decaying dry microburst while attempting to land at Sydney Airport. The approach was aborted and flight control was maintained but the aircraft touched down heavily, causing minor damage, before climbing to make a successful landing several minutes later. Following from this incident there has been work to investigate technology options for an operational wind shear alert system for Sydney Airport.

In this presentation we will review the cause of wind shear and its impact on aircraft operations, present details on the microburst encounter at Sydney Airport in 2007 and results from the study.


Thursday 17th June, 2:00pm - 3:00pm, Conference/Meeting Rooms, 9th floor east, 700 Collins St

The Southern Annular Mode and its influence on Australian intra-seasonal climate in POAMA

Andrew Marshall1*
Debbie Hudson2
Matthew Wheeler2
Harry Hendon2
Oscar Alves2

1 CAWCR CMAR Hobart
2 CAWCR BoM

We assess the ability of the Predictive Ocean Atmosphere Model for Australia (POAMA) to represent the Southern Annular Mode and its influence on intra-seasonal climate over Australia using a 27-year hindcast dataset. The analysis consists of two stages:

POAMA simulates SAM-related climate anomalies reasonably well at certain times of the year and for certain regions of Australia, despite notable biases in its representation of the SAM to the south and east of the continent. The model reproduces Australian rainfall anomalies most effectively throughout June-November (austral winter and spring), and least effectively throughout March-May (autumn). Its ability to reproduce these SAM-related anomalies is not strongly affected by initialization shock or by its drifting basic state.

Skilful prediction of the SAM by POAMA is limited to be about 9 days when calculated over all hindcast start months, and about 13 days for hindcasts initialised during strong SAM episodes. We show that the SAM contributes to intra-seasonal prediction skill for rainfall over New South Wales during winter and spring in weeks 2 and 3, but has little impact on the prediction skill over Australia during summer or autumn. Finally, an estimate of the potential predictability of the SAM suggests that the prediction skill may be further improved by up to a week through continued development of the POAMA dynamical prediction system.


Thursday 8th July, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Multiscale climate simulation over southern Africa using CCAM

Francois Engelbrecht

CSIR Nat. Res. Env.
South Africa

The conformal-cubic atmospheric model (CCAM) of the CSIRO has in recent years been applied extensively over southern Africa, for the purposes of short-range weather prediction, seasonal forecasting, climate simulation and the projection of regional climate change. High-resolution CCAM projections of climate over southern Africa have provided more insight into the dynamic circulation changes that may occur over the region in response to enhanced anthropogenic forcing. The projected changes in average circulation patterns, as well as in the frequency of occurrence of extreme weather events, are discussed in this presentation. A study where CCAM was used to downscale present-day climate (as described by reanalysis data) to ultra-high resolution (1 km in the horizontal) over southwestern South Africa is also presented. Regarding shorter time-scale applications, some verification results of CCAM short-range and seasonal weather forecasts over southern Africa are presented. The presentation concludes with a discussion of Earth System model development activities and plans at the CSIR in South Africa. These include the development of a new nonhydrostatic model core that is to be applied to study moist convection.


Monday 26th July, 2:00pm - 3:00pm, Conference Room 3, 6th floor, 700 Collins St

Victorian Centre for Climate Change Adaptation Research

Rod Keenan

University of Melbourne

Victorian communities have recently faced significant climate related challenges, including thirteen years of drought, the bushfires of 2003, 2006-07 and February 2009, extreme heatwaves and major storm events. The potential longer term impacts of climate change represent significant challenges for policy and management of human health, communities, public transport, urban settlements, infrastructure, emergency services, primary production and the natural environment. The Victorian Government has recognized this adaptation challenge and has invested in the establishment of a research centre to strengthen research on climate change adaptation and contributing to public policy development.

This seminar describes the development of the Centre, its objectives, research and other activities. The Centre represents a new type of collaboration between the Government and Victorian university sector - decision makers working with key research institutions to mainstream climate change considerations in state policy. The Centre aims to build adaptive capacity in government and the broader community through knowledge generation (a research program), new platforms for knowledge transfer, learning, consensus building and interaction between scientific, policy and wider stakeholder communities (regional and thematic think tanks), dissemination of research findings (through hosting annual forums) and facilitating international collaboration by hosting visiting research fellows.


Thursday 29th July, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

The impact of assimilating radar estimated precipitation rates on simulations of the July 17-18 Chicago flood

Xingbao Wang

CAWCR BoM

Rainfall prediction remains one of the most challenging problems in weather forecasting. In order to improve high-resolution quantitative precipitation forecast (QPF), a new procedure for assimilating rainfall rate derived from radar composite reflectivity has been proposed and tested in a numerical simulation of the Chicago flood storm of 17-18 July 1996. The methodology is based on the one-dimensional variation scheme (1DVAR) assimilation approach introduced by Fillion and Errico (1997) but applied here using the Kain-Fritsch convective parameterization scheme. The novel feature of our work is the continuous assimilation of radar estimated rain rate over a three hour period rather than a single assimilation at the initial (analysis) time. Most of the characteristics of this precipitation event, including the propagation, regeneration of mesoscale convective systems, the frontal boundary across the Midwest and the evolution of the low-level jet are better captured in the simulation as radar estimated precipitation rate is assimilated. The results indicate that precipitation assimilation during the early stage can improve the simulated mesoscale feature of the convection system and shorten the spin-up time significantly. Comparison of precipitation forecasts between the experiments with and without the 1DVAR indicates that the 1DVAR scheme has positive impact on the QPF up to 36 hours in terms of the Bias and Bias Equalized Threat scores.


Tuesday 10th August, 11:00am - 12:00pm, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Modelling of climate and climate variability

John You

University of Sydney




Wednesday 11th August, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

4d-VAR for dummies

Jeff Kepert

CAWCR BoM

Under ACCESS, we have moved into the brave new world of 4D-Var. The changes will affect everyone who uses numerical analyses or forecasts. We've all heard that 4D-Var is better, but don't really understand why. Nor what those pesky adjoints are, nor why they're needed. This seminar will attempt to answer these questions and more, in a lively, fun-filled session!!!


Thursday 12th August, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Down-selection of NWP ensemble configurations

Jared Lee

Department of Meteorology
Pennsylvania State University

Numerical weather prediction (NWP) model output is typically used to drive atmospheric transport and dispersion (AT&D) models. To assess the meteorological uncertainty, ensembles of NWP models are often used; the spread in the ensemble predictions is correlated to forecast uncertainty. To obtain appropriate spread in concentration predictions from AT&D models, the NWP ensemble should represent 'good' spread in low-level wind direction and atmospheric boundary layer (ABL) depth. To adequately sample the probability distribution function of the forecast atmospheric state, it is necessary to account for several sources of uncertainty, including the initial conditions, lateral boundary conditions, and model physics parameterizations. Limited computational resources typically constrain the size of ensembles, so choices must be made about which members to include when configuring an ensemble. This study examines an NWP ensemble that varies physics parameterizations for 18 randomly selected forecast periods in June-July-August 2009. Statistical guidance methods are employed to verify the ensemble forecasts and to down-select a small number of physics configurations to be used in a future ensemble that will also incorporate initial condition and lateral boundary condition variability. Verification is focused on meteorological parameters at the surface and in the ABL that are the most relevant to AT&D modelling.


Thursday 19th August, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

CO2 observations from space - status and plans

Peter Rayner

School of Earth Sciences
University of Melbourne

The distribution of CO2 fluxes and their controlling processes can be determined using measurements of concentration and inverse methods. The main limitation today is a lack of concentration measurements. Satellite measurements promise to expand greatly the spatial coverage but are subject to many problems of their own. In this talk I will review the current status of various measurement approaches and attempts to use them. I will focus on the use of thermal infrared measurements from the AIRS and IASI instrument as used in the ECMWF asimilation system and on the Japanese GOSAT instrument. Attempts to build a consistent end-to-end system are compromised by the number of different models used in the chain of inference. This is particularly critical when we try to feed the knowledge gained on processes controlling carbon fluxes to improved climate prediction. I will describe a new project using the Unified Model that will address some of these inconsistencies.


Friday 17th September, 10:00am - 11:00am, Conference/Meeting Rooms, 9th floor east, 700 Collins St

Modelling fire weather interactions (tbc)

Janice Coen

NCAR



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