Australia is known as the lucky country, with beautiful beaches, stunning landscapes, amazing flora and fauna, cosmopolitan cities and a thriving economy. But Australia is also a dangerous continent, as along with a variety of deadly animals we are prone to many of the different types of natural disasters that can cause damage and loss. Bushfires, tropical cyclones, severe convective storms and destructive low pressure systems are annual events, with insurance losses in the billions each year.

COMBUS Pty Limited is an actuarial consulting and catastrophe modelling firm specialising in helping insurance companies quantify and manage their large scale risk to natural and man-made disasters. We build catastrophe simulation models for Australia and provide consultative advice in the areas of catastrophe model development, model evaluation and reinsurance optimisation.


We have models available now to address your needs around Australian perils. We model the magnitude of large events and the frequency of smaller events, as well as correlations between the different perils due to regional weather patterns. We can provide your financial modelling system with the inputs it requires to simulate periods taking account of non-Poisson event clustering and cross-peril correlations, allowing you to more realistically model third and fourth event covers.


Ash Wednesday 1983
Black Saturday 2009
Canberra Fires 2003
The bushfire peril model covers fires in grassland, scrub or forest that cover wide areas and cause damage and loss to the environment and property. The event occurrence model is based on parameters such as temperature, humidity and wind speed and the probability of building loss takes into account vegetation type as well as physical distance.

Severe Convective Storm

Sydney Hailstorm 1999
Brisbane Hailstorm 1985
Sydney Hailstorm 1990
The severe convective storm model covers thunderstorm events due to instability in different layers of the atmosphere which can include the loss-causing sub-perils of strong winds, flooding, hail, tornadoes and lightning. These events tend to last for a number of hours with the most damage occurring over a short period of time, unlike other weather events which may last for more than one day.

Low Pressure System

SEQ Floods 2011
Newcastle Storm 2007
East Coast Low NSW 2015
The low pressure system model covers five different categories of Australian weather which have similar event features and mixes of damage and loss from sub-perils. The five weather types are East Coast Lows, Eastern Low Pressure Troughs, West Coast Troughs, Southern Ocean Lows and Monsoonal Low Pressure Troughs.


Cyclone Tracy 1974
Cyclone Wanda 1974
Cyclone Yasi 2011
The full tracks of each cyclone are modelled, including events crossing the coastline and those bypassing coastal regions. For each event in the database the maximum wind speed is determined for each location of interest and using that wind speed, modified by adjustments for terrain and topography, loss to individual buildings and contents is estimated for wind, flood and storm surge.


Newcastle 1989
Ellalong 1994
Meckering 1968
The earthquake model includes events with epicentres in Australia and in surrounding regions that lead to significant ground motion for Australian exposures. Site intensities in each modelled event are estimated based on a blend of published attenuation studies while damage to property takes account of Australian design codes.


The COMBUS models are available in an Aggregate Loss Model form which runs at Australian CRESTA level for a variety of exposure classes of business. Outputs from the system include Event Loss Tables (ELT), Yearly Loss Tables (YLT) and Probable Maximum Loss results (PML) for a range of return periods. YLTs may be generated for 10,000 or 100,000 years either treating the perils as independent or allowing for event clustering and cross peril correlations. The COMBUS models are currently (October 2017) available in three licensed forms.


The COMBUS models are now available directly within the Oasis Loss Modelling Framework. The models have been implemented within the KTools architecture and can be run on standalone computers, on a company network or on an internal company cloud environment. More information on the Oasis Loss Modelling Framework can be found here.


The full suite of COMBUS models are available on ModEx, the cat risk modelling platform powered by the Oasis Loss modelling Framework. More information about the cat risk modelling platform ModEx can be found here.


COMBUS has developed a spreadsheet user interface which performs all the calculations to create ELTs, YLTs and PMLs for any or all combinations of peril and sub-peril. The spreadsheet frontend provides a simple to use and easy to understand interface for companies not adopting Oasis Loss Modelling Framework that produces modelling outcomes in an efficient manner.


COMBUS Pty Limited has unrivalled expertise and experience in Australia addressing the needs of insurers and the business implications of exposure to losses from natural and man-made disasters. We provide consultative advice in the following areas:

Catastrophe model development, evaluation and use
Industry Exposure Databases
Realistic Disaster Scenario analysis
Concentration risk pricing and portfolio growth management
Reinsurance pricing, optimisation and cost allocation

We are registered as an actuarial consulting firm with the Australian Actuaries Institute.


COMBUS is based in the Southern Highlands of New South Wales, a rural environment approximately halfway between Sydney and Canberra. Our office is located in Clarence House, a collaborative workspace designed for professional services and technology providers.

COMBUS Pty Limited
PO Box 860 Moss Vale NSW 2577
Phone: +61 2 4868 2451
ABN : 43-101-402-573

Please contact us using the form below if you would like more details on our models and services