@article {bnh-5162, title = {Analysis of rapid damage assessment data following severe windstorm events}, journal = {Australian Journal of Emergency Management}, volume = {32}, year = {2017}, month = {10/2017}, abstract = {

The Cyclone Testing Station (CTS) and partners have conducted forensic damage assessments in Australia following severe windstorm events for over four decades. The information collected is used for building science research that provides the evidence base needed for improvements to building codes and development of damage mitigation solutions. The Queensland Fire and Emergency Services (QFES) operate Rapid Damage Assessment (RDA) teams in the aftermath of major disasters (e.g. cyclone and bushfire) to collect and disseminate information on extent of damage to buildings in impacted communities. These data enables focused and coordinated response in the immediate aftermath of an event and better planning for event recovery. This paper explores the use of QFES RDA datasets in analysing the damaging effects of severe windstorm events. Two case studies are discussed: a supercell that hit Brisbane on 27 November 2014 and Tropical Cyclone Debbie that made landfall along the northern Queensland coastline in March 2017. Where possible, damage data are combined with hazard information (dual-Doppler radar horizontal wind fields) and their relationship is investigated. The analysis demonstrates that RDA data are not only useful in response and recovery phases, but also have value for research aiming to better understand building failures and reduce damage in future events.

}, url = {https://ajem.infoservices.com.au/items/AJEM-32-04-21}, author = {Daniel Smith and Richard Krupar III and David Henderson and M. S. Mason} } @article {bnh-3805, title = {A modified Severe Tropical Cyclone Marcia (2015) scenario: wind and storm tide hazards and impacts}, number = {258}, year = {2017}, month = {07/2017}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

This report describes research undertaken to develop a modified Severe Tropical Cyclone Marcia (2015) scenario and details its wind and storm tide-related impacts on buildings and society in Livingstone Shire and the Rockhampton Region. A perturbed version of the original track taken by Cyclone Marcia was chosen to create an ensemble event set of possible worstcase wind and storm tide inundation scenarios for the region of interest and the key findings of this work are as follows:

Future work will seek to improve the exposure dataset used in this scenario. Improvements will include adding critical infrastructure such as power lines and water distribution networks, as well as, updating Geocoded {\textendash} National Address File (G-NAF) building level estimates of property value, contents value and population using ground truth data. The wind, rainfall and storm surge hazard models and associated vulnerability models used in the current multi-hazard model framework will also be updated. The wind hazard model will include new environmental parameters (i.e. sea surface temperature and deep layer wind shear) that influence tropical cyclone formation and maintenance. This improvement will help generate more realistic cyclones wind fields. The rainfall hazard model will be calibrated to Australian surface terrain and topography to simulate inland rainfall enhancements and will be paired with a hydrodynamic runoff model to simulate inland flooding damage and impacts to buildings, critical infrastructure and society during the post-landfall phase. The storm tide hazard model will be updated to simulate inland flooding impacts (e.g. surge-induced riverine flooding) by including the influence of the underlying surface roughness overland and expanding the mesh inland. Updates to the wind and flood vulnerability models will be made as new results surface from Bushfire and Natural Hazard CRC projects aiming to develop and improve these types of models. The flood vulnerability model will be updated to include flow velocity and wave effects. Finally, combined or joint hazard impacts (i.e. wind driven rain) will be evaluated to develop joint-hazard damage functions in future model releases.\ 

}, issn = {258}, author = {Richard Krupar III and M. S. Mason} } @article {bnh-4230, title = {Severe wind hazard preliminary assessment: Tropical Cyclone Debbie, Whitsunday Coast, Queensland, Australia}, year = {2017}, month = {03/2017}, institution = {James Cook University}, address = {Townsville}, abstract = {

Severe Tropical Cyclone Debbie was a category 4 system that made landfall near Airlie Beach (Figure 1) on the north Queensland coast at midday on the 28th of March, 2017. As part of a continuing effort to better characterize wind fields that impact communities during severe wind events, the Cyclone Testing Station (with collaborators from the Wind Research Laboratory at The University of Queensland) deployed SWIRLnet (Surface Weather Relay and Logging Network) weather stations to the region prior to Debbie{\textquoteright}s landfall. Six SWIRLnet towers (3.2 m high anemometers placed in the communities likely to be affected) collected data continuously prior to, during and after landfall. Three towers were deployed in the Ayr/Home Hill region, two in Bowen and one in Proserpine (Figure 2). This Preliminary Assessment Report details the initial observations from these towers, compares these with Bureau of Meteorology Automatic Weather Station observations, and makes some preliminary comment on the damage to structures in stormaffected communities.

}, url = {https://www.jcu.edu.au/__data/assets/pdf_file/0005/422951/TC-Debbie-Rapid-Assessment-Report_v8.pdf}, author = {Thomas Kloetzke and Korah Parackal and D. J. Smith and Richard Krupar III and Leblais, Alex and Humphreys, M and Spassiani, Alessio and M. S. Mason and David Roueche and David O Prevatt and David Henderson and Boughton, Geoffrey N.} } @article {bnh-4227, title = {Tropical Cyclone Debbie: damage to buildings in the Whitsunday Region}, number = {63}, year = {2017}, month = {06/2017}, institution = {James Cook University}, address = {Townsville}, abstract = {

Tropical Cyclone Debbie (TC Debbie) was classified by the Bureau of Meteorology (BoM) as a Category 4 cyclone and crossed the Queensland coast north east of Airlie Beach around midday on Tuesday 28 March 2017.

Before the event, the Cyclone Testing Station (CTS) deployed six mobile anemometers (SWIRLnet) in the area between Ayr and Proserpine. After the event, CTS teams investigated the performance of houses; larger residential structures such as apartments, strata properties and resort accommodation; commercial and public buildings; and sheds. The study area included the communities of Bowen, Proserpine, Airlie Beach, Hamilton Island, Dingo Beach, Wilson{\textquoteright}s Beach and Conway Beach. A wind field was developed using CTS and BoM anemometer data and showed that buildings within the study area experienced wind speeds lower than their relevant design wind speed.

CTS teams assessed the causes of damage to buildings from wind, wind-driven rainwater and storm surge. Inadequate tie-down details between battens and rafters or trusses, and between the roof structure and walls caused many of the structural failures in buildings constructed before the 1980s. Tie-down connections between roof structure and walls that had been inappropriately detailed also failed on some recently constructed buildings. Connections between verandah beams and posts on some buildings with larger verandahs also failed. \ 

This study confirmed the findings of previous damage investigations concerning the vulnerability of: windows with inadequate fixings, window and door furniture; poorly fixed flashings, gutters and soffit linings; large access doors that had not been strengthened so that they complied with AS/NZS4505; lightweight sheds; and fences.

Many occupants of newer buildings reported significant damage from wind-driven rain entering through windows and doors or under flashings even though there was no structural damage to the building. Many people reported that they mopped up water in front of windward wall windows during periods of maximum winds, which exposed them to risk of injury. Further research is required to improve performance of building elements that leak during high winds.

The storm tide generated during TC Debbie was lower than predicted because the cyclone crossed the coast after high tide. Lower-lying buildings in Wilson Beach were inundated to a height of up to 1.1 m causing damage to wall linings, built-in cupboards, floor coverings and contents. In some cases, wave action broke cladding elements and windows. Wave action and scour undercut footings in some buildings on Hamilton Island and Wilson Beach.\ 

The report provides recommendations to improve the performance of building structure and cladding systems including: adequate detailing for roof to wall connections; improved fixing of flashings, retrofitting options for older buildings; improvements in windows and door furniture under repeated wind loads; and revision of storm surge guidelines.

}, isbn = {978-0-9954470-4-2}, issn = {63}, url = {https://www.jcu.edu.au/__data/assets/pdf_file/0009/461178/TC-Debbie-report.pdf}, author = {Boughton, Geoffrey N. and Falck, D. J. and David Henderson and D. J. Smith and Korah Parackal and Thomas Kloetzke and M. S. Mason and Humphreys, M and Navaratnam, S and Bodhinayake, G and Simon Ingham and John Ginger} } @article {bnh-4240, title = {Using realistic disaster scenario analysis to understand natural hazard impacts and emergency management requirements: annual project report 2016-17}, number = {347}, year = {2017}, month = {09/2017}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

The study of historical occurrences of natural disasters only provides a very limited view of the full range of risk Australia is exposed to. Catastrophe models have been designed as a tool to extrapolate beyond past experience and as such can help risk practitioners prepare for the types of events yet to be seen.

In this project we apply the same techniques at the core of catastrophe models to design realistic disaster scenarios. The focus is not only on the hazard magnitude to be expected from rare extreme events but also on the likely impact in terms of building damage, infrastructure disruption and injuries / loss of human lives. To provide a global picture of natural disaster risk in Australia a range of perils and locations have been selected through the 3 years of the project. The scenarios cover Tropical Cyclones, Earthquake, Heatwaves and flooding induced by East Coast Lows while the regions around Adelaide, Melbourne, Northern New South Wales and Southeast Queensland are at the center of our analysis.

To facilitate communication of our key results a web content has been drafted to provide a description of each catastrophic event studied. The web content is hosted by the Australian Institue for Disaster Resilience (AIDR) knowledge Hub and targets a broader audience than the technical reports delivered as part of the project{\textquoteright}s milestones.

It is our hope that emergency services can leverage the type of information generated from such scenarios to assess their capabilities to cope with the response and recovery task. The web content also offers a source of information for a wider audience and plays a role in educating the general public on the potential threat posed by Australian natural disasters.

}, issn = {347}, author = {Thomas Loridan and M. S. Mason} } @conference {bnh-2938, title = {Evaluating topographic influences on the near-surface wind field of Tropical Cyclone Ita (2014) using WRF-ARW}, booktitle = {AFAC16}, year = {2016}, month = {08/2016}, publisher = {Bushfire and Natural Hazards CRC}, organization = {Bushfire and Natural Hazards CRC}, address = {Brisbane}, abstract = {

Tropical Cyclone (TC) Ita (2014) was a major storm that affected coastal areas of Northeast Queensland. Topographic features along the coastline are known to modify the structure and intensity of such events. This study utilises the Advanced Research version of the Weather Research and Forecasting (WRF-ARW) model to investigate topographic influences during the landfall phase of TC Ita. While the removal of topography over the whole domain steers the modelled TC far away from the landfall point, removing topography from only a smaller area allowed an investigation of the topographic influence on near-surface wind conditions in that area. Flow over the region of removed topography exhibit smaller inland velocity gradients for winds flowing onshore and a sharper acceleration of winds as they moved offshore.

}, author = {Thomas Kloetzke and M. S. Mason and Richard Krupar III} } @conference {bnh-2954, title = {Forecasting the impact of tropical cyclones using global numerical weather prediction ensemble forecasts: a Tropical Cyclone Marcia (2015) wind and rainfall case study}, booktitle = {AFAC16}, year = {2016}, month = {08/2016}, publisher = {Bushfire and Natural Hazards CRC}, organization = {Bushfire and Natural Hazards CRC}, address = {Brisbane}, abstract = {

Wind hazard and rainfall models were coupled to estimate hourly open exposure maximum three-second gust wind speeds and rainfall totals for Tropical Cyclone (TC) Marcia (2015) using Bureau of Meteorology (BoM) best track data. Yeppoon The Esplanade automatic weather station (AWS) was used to perform a verification of the simulated hourly open exposure maximum three-second gust wind speed and rainfall totals with observed estimates. Preliminary verification results reveal that the wind hazard model overestimates the AWS hourly maximum three-second gust wind speed and the rainfall model underestimates the hourly total rainfall. Ensemble prediction system (EPS) forecasts from the European Centre for Medium-Range Forecasts (ECMWF) were examined to determine their utility in simulating TC Marcia{\textquoteright}s wind and rainfall fields and impacts. The ECMWF EPS fails to capture Marcia{\textquoteright}s rapid intensification at 72, 48, and 24 hours leading up to the landfall. A time-varying calibration factor is required at each forecast initialization in order to adjust each ensemble forecast member{\textquoteright}s minimum central pressure to a more realistic estimate of the minimum central pressure to properly simulate impacts to humans and the built environment.

}, author = {Richard Krupar III and M. S. Mason} } @article {bnh-2588, title = {A southeast Queensland tropical cyclone scenario}, number = {159}, year = {2016}, month = {02/2016}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

Tropical cyclones are devastating events for the communities they affect. Realistic disaster scenario analysis is a simulation technique that can be used by disaster management agencies to understand the potential impacts of these storms and help them better prepare for their inevitable occurrence. This report describes research undertaken to develop such a scenario and detail its impacts.

The primary aim of this project was to assess the potential impacts of a category 4 storm impacting the populous region of southeast Queensland. A perturbed version of the track taken by Severe Tropical Cyclone Dinah in 1967 was chosen for simulation and the key findings of this work are as follows:

Future work will further develop both the wind hazard and vulnerability models used in the current simulation and will seek to include new model components that simulate tropical cyclone induced rainfall, coastal inundation and their impacts.\ 

}, issn = {159}, author = {M. S. Mason} } @conference {bnh-2092, title = {Investigation of damage: Brisbane 27 November 2014 sever storm event - non peer reviewed extended abstract}, booktitle = {Adelaide Conference 2015}, year = {2015}, address = {Adelaide, Australia}, abstract = {

Research proceedings from the Bushfire and Natural Hazards CRC \& AFAC Conference in Adelaide, 1-3 September 2015.\ 

}, author = {Korah Parackal and M. S. Mason and David Henderson and D. J. Smith and John Ginger} } @article {bnh-2344, title = {Using natural disaster scenarios to better understand emergency management requirements: Annual project report 2014-2015}, number = {137}, year = {2015}, month = {02/11/2015}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

This project aims to produce realistic natural disaster event scenarios to help emergency managers understand and prepare for eventual natural disasters. Scenarios consist of numerical data such as maps and tables representing the impacts of a plausible natural disaster scenarios; plausibility is determined by analyzing past event occurrence, intensity and impact data. Scenarios are created by using a suite of analysis tools including statistical inference, expert elicitation and comparative analysis in order to create abstract representations of an event, which is as close to reality as possible.

Over the past year, this project has delivered its first two complete scenarios, namely, an earthquake of magnitude 6.0 occuring in the Para fault underneath Adelaide CBD, and a tropical cyclone affecting SE Queensland (to be delivered third quarter 2015). The outcomes of the Adelaide scenario comprise:

-\ \ \ \ \ \  Total aggregated damage to residential and commercial properties

-\ \ \ \ \ \  Maps showing the distribution and intensity of damage to buildings and casualties

-\ \ \ \ \ \  Distribution of infrastructure and essential facilities (hospitals, schools, roads, etc) that would be destroyed in such an event

-\ \ \ \ \ \  Comparative analysis with past events

These outcomes and their detailed interpretation were delivered in a corresponding technical note. Results were presented to end-users in a workshop held in Adelaide including representatives of SAFECOM and other SA government agencies including SA police and DPTI. According feedback from end-users, future scenarios should:

-\ \ \ \ \ \  Take into account the distribution of vulnerable populations (elderly, disabled)

-\ \ \ \ \ \  Account for the relationship between different infrastructure systems (e.g. how damage to roads impacts hospital operations).

-\ \ \ \ \ \  Cost of response and cost-benfit analysis of mitigation measures

Following this, work on year 2 scenarios has begun. A workshop was held with NSW SES end user to determine appropriate scenario events of interest to their agency. This complemented comments and suggestions drawn from the full end-user community at the most recent RAF. Resultant scenarios to be explored over the coming year will be:

  1. A sequence of minor and major flood events in NSW
  2. Heatwave mortality during a major event in VIC
  3. Tropical cyclone induced flooding in SE Qld and northern NSW
}, issn = {137}, author = {Felipe Dimer de Oliveira and M. S. Mason} } @article {bnh-3381, title = {Vulnerability of buildings and civil infrastructure to tropical cyclones: A preliminary review of modelling approaches and literature}, number = {244}, year = {2015}, month = {02/2017}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

This report will focus predominantly on the response of assets to extreme wind and flood (coastal and inland inundation) and each asset/network class will be further investigated under the following categories.

o Residential buildings

o Other building types, e.g. commercial, industrial

o Power systems
o Road and transport
o Water supply
o Telecommunication

Given the broad scope of this field, we do not attempt an all-encompassing overview of all works ever undertaken on the topic (particularly for civil infrastructure), but instead focus on those models of most benefit to the scenario analyses required of this project. Because many of the models have been developed internationally, a primary question to be answered is whether they are applicable to Australian conditions.\ 

This document forms a key component of the BNHCRC project {\textquotedblleft}Using realistic disaster scenario analysis to understand natural hazard impacts and emergency management requirements{\textquotedblright} and is structured as follows. First we begin with a brief introduction to the theory and concepts involved in vulnerability modelling. Existing building and civil infrastructure vulnerability models are then reviewed in sections 3 and 4, with the sub-hazards of wind and flood addressed separately where appropriate. Recommendations outlining suitable tools/models for implementation will be made, with a summary of literature presented in tabular form at the end of each section. The concept of network interdependence will be briefly reviewed in section 6 as it applies to network infrastructure and a summary of all recommendations will be provided in 7.\ \ 

}, issn = {244}, author = {M. S. Mason and Korah Parackal} } @article {bnh-3452, title = {Estimating present day extreme water level exceedance probabilities around the coastline of Australia: tropical cyclone-induced storm surges}, journal = {Climate Dynamics}, volume = {42}, year = {2014}, month = {01/2014}, pages = {139-157}, chapter = {139}, abstract = {

The incidence of major storm surges in the last decade have dramatically emphasized the immense destructive capabilities of extreme water level events, particularly when driven by severe tropical cyclones. Given this risk, it is vitally important that the exceedance probabilities of extreme water levels are accurately evaluated to inform risk-based flood and erosion management, engineering and for future land-use planning and to ensure the risk of catastrophic structural failures due to under-design or expensive wastes due to over-design are minimised. Australia has a long history of coastal flooding from tropical cyclones. Using a novel integration of two modeling techniques, this paper provides the first estimates of present day extreme water level exceedance probabilities around the whole coastline of Australia, and the first estimates that combine the influence of astronomical tides, storm surges generated by both extra-tropical and tropical cyclones, and seasonal and inter-annual variations in mean sea level. Initially, an analysis of tide gauge records has been used to assess the characteristics of tropical cyclone-induced surges around Australia. However, given the dearth (temporal and spatial) of information around much of the coastline, and therefore the inability of these gauge records to adequately describe the regional climatology, an observationally based stochastic tropical cyclone model has been developed to synthetically extend the tropical cyclone record to 10,000\ years. Wind and pressure fields derived for these synthetically generated events have then been used to drive a hydrodynamic model of the Australian continental shelf region with annual maximum water levels extracted to estimate exceedance probabilities around the coastline. To validate this methodology, selected historic storm surge events have been simulated and resultant storm surges compared with gauge records. Tropical cyclone induced exceedance probabilities have been combined with estimates derived from a 61-year water level hindcast described in a companion paper to give a single estimate of present day extreme water level probabilities around the whole coastline of Australia. Results of this work are freely available to coastal engineers, managers and researchers via a web-based tool (www.sealevelrise.info). The described methodology could be applied to other regions of the world, like the US east coast, that are subject to both extra-tropical and tropical cyclones.

}, doi = {10.1007/s00382-012-1653-0}, url = {https://link.springer.com/article/10.1007\%2Fs00382-012-1653-0}, author = {Ivan D. Haigh and Leigh R. MacPherson and M. S. Mason and E.M.S Wijeratne and Charitha Pattiaratchi and R Crompton and Steve George} } @article {bnh-3451, title = {Estimating present day extreme water level exceedance probabilities around the coastline of Australia: tides, extra-tropical storm surges and mean sea level}, journal = {Climate Dynamics}, volume = {42}, year = {2014}, month = {01/2014}, pages = {121-138}, chapter = {121}, abstract = {

The occurrence of extreme water levels along low-lying, highly populated and/or developed coastlines can lead to considerable loss of life and billions of dollars of damage to coastal infrastructure. Therefore it is vitally important that the exceedance probabilities of extreme water levels are accurately evaluated to inform risk-based flood management, engineering and future land-use planning. This ensures the risk of catastrophic structural failures due to under-design or expensive wastes due to over-design are minimised. This paper estimates for the first time present day extreme water level exceedence probabilities around the whole coastline of Australia. A high-resolution depth averaged hydrodynamic model has been configured for the Australian continental shelf region and has been forced with tidal levels from a global tidal model and meteorological fields from a global reanalysis to generate a 61-year hindcast of water levels. Output from this model has been successfully validated against measurements from 30 tide gauge sites. At each numeric coastal grid point, extreme value distributions have been fitted to the derived time series of annual maxima and the several largest water levels each year to estimate exceedence probabilities. This provides a reliable estimate of water level probabilities around southern Australia; a region mainly impacted by extra-tropical cyclones. However, as the meteorological forcing used only weakly includes the effects of tropical cyclones, extreme water level probabilities are underestimated around the western, northern and north-eastern Australian coastline. In a companion paper we build on the work presented here and more accurately include tropical cyclone-induced surges in the estimation of extreme water level. The multi-decadal hindcast generated here has been used primarily to estimate extreme water level exceedance probabilities but could be used more widely in the future for a variety of other research and practical applications.

}, doi = {10.1007/s00382-012-1652-1}, url = {https://link.springer.com/article/10.1007/s00382-012-1652-1}, author = {Ivan D. Haigh and E.M.S Wijeratne and Leigh R. MacPherson and Charitha Pattiaratchi and M. S. Mason and R Crompton and Steve George} }