1. Yelena Kropivnitskaya, Kristy F. Tiampo,
Jinhui Qin and Michael A. Bauer
A Simulation Approach for Better Understanding of Natural Catastrophe Hazard and Risk

2. Motivation
Deep uncertainty concerning the future evolution of disaster losses
Socio-economic damages caused by extreme natural events, have risen steadily for decades (Munich Re,2015);
Damage drivers:
economic growth;
changes in the localization of assets and population (Pielke and Landsea, 1998);
after 2004 and 2005 hurricane seasons in the North Atlantic - climate change (Emanuel, 2005a, 2005b; Webster et al., 2005).
The design of long-lived infrastructure much more difficult (inadequate design and ill-adaptation to climate conditions);
Can provoke significant losses (Hallegatte, 2006a).

3. Area of Interest – Eastern Canada (Montreal)
Earthquake Catalogue (Fereidoni et al.,2011)
Population Density
Figure credit – (Atkinson, 2011)
Figure credit – (NRC, 2001)

4. Eastern Canada seismic zone model (GSC)
Thirty-nine zones (Adams an Halchuk, 2003, 2004; Halchuk and Adams, 2008)
with a magnitude-recurrence parameters, maximum magnitudes and depths
Consists of two alternative source zone models:
the H model - historical seismicity,
the R model - regional tectonic structure.

5. Eastern Canada GMPE Set (Atkinson and Adams, 2013)
New way to quantify epistemic uncertainty:
Using existing peer-reviewed GMPEs to construct a set of three weighted equations (medium (M), high (H) and lower(L)) for each region and event type
M4.5
M5.5
M6.5
M7.5
Epicentral distance, km
Log(PSA), cm/sec^2
Frequency = 10 Hz H M
GMPE L GM

6. Montreal Soil Map (Rosset et al. 2014)
The Montreal soil map is used to find amplifications for:
PGV,
PGA,
response spectra at frequencies of 1, 5, and 10 Hz.
Amplification values are calculated based on Boore and Atkinson (2008) relations:
a linear part (Flin) which is dependent only for Vs30;
a non-linear term (Fnl) which is a factor of both Vs30 and a reference ground motion.
In this case, the reference motion is the predicted peak ground acceleration in g for Vref = 760 m/s. The combination of these two terms is the total amplification:
Fs = Flin + Fnl

7. Originally:
EqHaz1 - The number of records in each synthetic catalog is limited to 1,000,000
EqHaz2 - Could have no more than 100,000 points

8. Parallel execution Each single operator executes on a single core
The entire process is divided into 3 stages:
- The first stage is exactly the same as before
- Monte Carlo simulations for the synthetic catalogue
- Spatial grid decomposition
The number of records in the each synthetic catalog is now limited to 10,000,000

9. Output
Example - Mean hazard map for a 2475 year return period for pseudo acceleration at T=0.1 sec
Resolution of mean hazard map improved to 2,500,000 points
The number of periods is the specified input parameter (in our case 0.2 sec, 1.0 sec and 2.0 sec)

10. 2475 Year Stochastic Subcatalogs for Eastern Canada
Montreal, located in the seismically active region of the western Quebec (WQU) seismic zone, is one the largest and most populated cities in eastern Canada.
Figure demonstrates two random runs of seismicity in the region based on seismic zones model (Halchuk and Adams, 2008).

11. Contributions of different magnitude-distance bins to PGA hazard in Montreal from a 10 million year synthetic catalog
The maximum contribution is observed at a distance of approximately 50 km for magnitudes between 6 and 7.5.
There also are two peaks at 0.1 Hz frequency which are close to 50 km and 100 km for the same magnitudes.
At 1 Hz frequency, the maximum contribution also occurs at around 50 km.
The distance range of maximum impact seems to be wider however, starting at about 30 km and going up to approximately 70 km.
PGA

12. Scenarios from a 10 Million Year Synthetic Catalog for the Events with the Highest Contribution to Hazard
In this regions single seismic events dominate the hazard and lead to a high level of uncertainty of the input parameters in earthquake scenarios. The results of this work which are earthquake scenarios from a 10 million year synthetic catalog are an important input for the future uncertainty and PSHA model parameters analysis for Montreal city.
Scenario 1
M 7.5, depth 10km
epi ~40 km (WQU)
Scenario 2
M 7.5, depth 10km
epi ~340 km (CHV)

13. NE Atlantic Hurricane Extreme hurricanes occur with low frequency.
Low probability of North Atlantic Ocean hurricane landfall makes statistics are difficult to estimate.
Statistical methods can be employed to resample the historical data, creating a large number of tracks used to improve estimates of the probability extremes.
A spatial domain 39-48N and 60-85W

14. Historical Data Sources and Functional Form of Parameters Distribution
The historical best-track North Atlantic hurricane dataset (HURDAT2; Landsea et al. 2015) from 1851 to 2015:
genesis
translational speed and heading
central pressure over water
inland filling rate
maximum wind velocity
The extended best-track dataset (Demuth et al. 2006):
the radius of maximum wind
Poisson
Gaussian
Lognormal
Lognormal
(truncated)

15. Thank you