RMS recently spoke at the RAA's Catastrophe Modeling conference in Orlando, discussing U.S. flood risk, specifically about flood modeling, recent successes and future progress to improving the state of flood modeling.

1. U.S. FLOOD MODELING
Clare Salustro
Manager, Model Product Management, Americas Climate
©2014 Risk Management Solutions, Inc.
Confidential

2. Where
have we
been?
Where are
we now?
What’s
changed?
What’s
coming?

3. JULY 2013
US FLOOD
TIMELINE
MTA Cat Bond is first ever Cat
Bond for storm surge
JANUARY 2014
JUNE 2012
Partial delay of
Biggert-Waters
Biggert-Waters NFIP Reform Act signed into law
?
SEPTEMBER 2008
AUGUST 2005
Hurricane Katrina
Hurricane Ike
$2.7 Bn NFIP loss
$16.3 Bn NFIP loss
©2014 Risk Management Solutions, Inc.
Confidential
OCTOBER 2012
Hurricane Sandy
$7.8 Bn NFIP loss

4. Event
©2014 Risk Management Solutions, Inc.
$16.3B
Hurricane Sandy
2012
$7.8B
Hurricane Ike
2008
$2.7B
Hurricane Ivan
2004
$1.6B
2011
$1.3B
2001
$1.1B
Louisiana Flood
1995
$585M
Tropical Storm Isaac
Over half of total
NFIP payout
(since program
began in 1978)
from just two
years – 2005 and
2012 – driven by
coastal flood loss
2005
2012
$531M
Hurricane Isabel
2003
$493M
Hurricane Rita
2005
$472M
Hurricane Floyd
1999
$462M
Tropical Storm Lee
2011
$445M
Hurricane Opal
1995
$406M
Hurricane Hugo
1989
$376M
Hurricane Wilma
14 of top 15 NFIP
claims related to
Tropical Storms
and Hurricanes
Hurricane Katrina
Tropical Storm Alison
Flood risk in U.S. is
dominated by coastal flood
Claims
Hurricane Irene
NFIP: TOP 15
LOSSES
Year
2005
$365M
Confidential

5. NFIP: LOSS
HISTORY
Flood risk in U.S. is
dominated by coastal flood
Total NFIP Claims
in $Bn
(1978-present)
Contribution to
total (%)
Flooding from hurricanes and tropical storms
36.5
87%
Non-tropical cyclone-related flooding
5.7
13%
TOTAL
42.2
100%
Source
©2014 Risk Management Solutions, Inc.
Confidential

6. COASTAL
FLOOD
MODELING
ISN’T EASY
Storm surge processes are
complex
•
•
Must account for hurricane
characteristics over lifetime of
storm
Must model at very high resolution
RMS approach has evolved over
time and was well validated by
recent events such as Sandy
©2014 Risk Management Solutions, Inc.
Confidential

7. IT’S NOT JUST LANDFALL CHARACTERISTICS THAT MATTER
Windspeed
Cannot assume 1:1
relationship between wind and
surge severity at landfall
Storm surge impacts can be
more severe than indicated by
landfall characteristics
– Sandy (2012)
– Ike (2008)
– Katrina (2005)
170
160
150
140
Cat 5
Cat 4
130
120
110
100
90
80
©2014 Risk Management Solutions, Inc.
(mph) at landfall
Cat 3
Cat 2
Cat 1
Confidential
22
20
18
16
14
12
10
8
6
4
2
Surge height
(feet)
Katrina
Cat 5
Ike
Cat 4
Sandy
Cat 3
Cat 2
Cat 1

8. DIFFERENT APPROACHES TO STORM SURGE MODELING
Empirical Models
SLOSH
Hydrodynamic Models
• Lack of observations to train
on across all regions
• Doesn’t account for surge
development over life of
storm
• Difficult to deal with complex
coast-lines, bays, and
barrier islands
• (Sea, Lake, and Overland
Surge from Hurricane)
• Operational focus, widely
used for disaster planning
• Not certified for FEMA flood
modeling studies
• Grid resolution decreases
away from central point
• Physics-based calculation of
time-stepping storm surge
• Considered best practice for
FEMA flood modeling
studies
• Can control grid resolution –
put fine resolution grid cells
where they’re needed most
©2014 Risk Management Solutions, Inc.
Confidential

9. DIFFERENT APPROACHES TO STORM SURGE MODELING
Empirical Models
SLOSH
Hydrodynamic Models
• Lack of observations to train
on across all regions
• Doesn’t account for surge
development over life of
storm
• Difficult to deal with complex
coast-lines, bays, and
barrier islands
• (Sea, Lake, and Overland
Surge from Hurricane)
• Operational focus, widely
used for disaster planning
• Not certified for FEMA flood
modeling studies
• Grid resolution decreases
away from central point
• Physics-based calculation of
time-stepping storm surge
• Considered best practice for
FEMA flood modeling
studies
• Can control grid resolution –
put fine resolution grid cells
where they’re needed most
©2014 Risk Management Solutions, Inc.
Confidential

10. NUMERICAL
APPROACH:
SUPERCOMPUTING
RESOURCES
REQUIRED…
©2014 Risk Management Solutions, Inc.
Required 500
CPUs and 60
terabytes
of disk-space to
generate RMS
North Atlantic
Hurricane Model
storm surge
stochastic set
Confidential

11. RMS SURGE
MODELING:
NESTED MESH
FRAMEWORK
REGIONAL MESH
©2014 Risk Management Solutions, Inc.
TRACK SET
WIND FIELD
LOCAL MESH
FLOOD DEPTHS
Confidential

12. HIGH RESOLUTION COASTAL FLOOD MODELING
Detailed bathymetry and coastal topography: Southern Louisiana
•
Resolutions as fine as
100m
•
Ability to model complex
flows of water in and out of
bays and harbors
•
Manage and underwrite
coastal flood risk with
confidence, down to the
local level
©2014 Risk Management Solutions, Inc.
Confidential

13. ABLE TO MODEL REALISTIC COASTAL FLOODING
Previous model extent (parametric model)
©2014 Risk Management Solutions, Inc.
Current model extent (full hydrodynamic model)
Confidential

14. ABLE TO MODEL REALISTIC COASTAL FLOODING
Previous model extent (parametric model)
©2014 Risk Management Solutions, Inc.
Current model extent (full hydrodynamic model)
Confidential

15. RMS Storm Surge Model
WELL
VALIDATED
DURING
SANDY
• RMS model as
good as best data
developed by
FEMA
• Verified against
over 200
independent flood
observations
©2014 Risk Management Solutions, Inc.
Confidential
FEMA Flood Extent

16. LESSONS
LEARNED
FROM SANDY
•
•
•
High-value contents in
basements within central
business district took
many by surprise
Highlighted gaps in data
capture, limited
exposure information
Sandy Data Call
currently underway
©2014 Risk Management Solutions, Inc.
Confidential

17. WHERE DOES
THIS LEAVE
US NOW?
Only%modeling%
company%that%
integrates%a%full%
dynamic%storm%surge%
model%into%its%
hurricane%model%suite%%
©2014 Risk Management Solutions, Inc.
High%quality,%well9
verified%model%for%
driver%of%U.S.%flood%loss%
Confidential
Viable%alternate%view%
of%risk%from%FEMA%for%
coastal%flood,%available%
now%

18. COASTAL FLOOD VIEW ALREADY AVAILABLE
100-YEAR FLOOD ELEVATION: FEMA VERSUS RMS
FEMA
©2014 Risk Management Solutions, Inc.
Confidential
RMS

19. Completing
the U.S.
Flood
Solution

20. GOAL:
Develop modeling solution covering all
sources of flooding in US
! Tropical Cyclone Surge
! Tropical Cyclone Precipitation
! Non-Tropical Cyclone Precipitation
©2014 Risk Management Solutions, Inc.
Confidential

21. GOAL:
Develop modeling solution covering all
sources of flooding in US
" Storm Surge within Hurricane Model
" Tropical Cyclone Surge
! Tropical Cyclone Precipitation
! Non-Tropical Cyclone Precipitation
©2014 Risk Management Solutions, Inc.
Suite of US Flood products:
Confidential

22. GOAL:
Develop modeling solution covering all
sources of flooding in US
" Storm Surge within Hurricane Model
" Tropical Cyclone Surge
! Tropical Cyclone Precipitation
! Non-Tropical Cyclone Precipitation
©2014 Risk Management Solutions, Inc.
Suite of US Flood products:
! US Flood HD Model
Confidential
coming'soon!!

23. GOAL:
Develop modeling solution covering all
sources of flooding in US
" Storm Surge within Hurricane Model
" Tropical Cyclone Surge
! Tropical Cyclone Precipitation
! Non-Tropical Cyclone Precipitation
©2014 Risk Management Solutions, Inc.
Suite of US Flood products:
! US Flood Hazard Data Product
! US Flood HD Model
Confidential
coming'
soon!!

24. New US Inland Flood model (lower 48
states) set to be released on RMS(one)
U.S. Major River Basins
Probabilistic model is precipitationdriven
Includes tropical cyclone and
non-tropical cyclone precipitation
Covers both floodplain (major and
minor) and off-floodplain (i.e. flash
flooding) events
Continuous simulation accounts for
antecedent conditions

25. LARGEST MODEL EVER BUILT
Number of grid cells in
US Inland Flood Model
Number of grid cells in
US Storm Surge Model
32 Mn!
©2014 Risk Management Solutions, Inc.
5.7 Bn!
Confidential

26. WHY NOW?
Not computationally possible
previously
We’re able to do it now
because:
• Migrated heavy
processing from
conventional CPUs to
GPUs – gain of over 200x
• RMS(one) reduces
storage need for client
©2014 Risk Management Solutions, Inc.
Confidential

27. BUILDING
MODELS IN
RMS(ONE)
HD Simulation: Allows for continuous simulation of
events
– Similar meteorological events can lead to
very different hazard & loss events
o Antecedent conditions strongly
influence the severity of a flood
– Able to capture clustering and correlation
•
New financial model enabled by Contract
Definition Language (CDL)
– Properly model hours clause and complex
flood policy terms
•
©2014 Risk Management Solutions, Inc.
•
Performance offered by the Cloud
Confidential

28. US FLOOD MODEL COMPONENTS
Geospatial
Data
Underlying
elevation
dataset and
derivative
elements
©2014 Risk Management Solutions, Inc.
Stochastic
Event Module
Hazard
Module
Vulnerability
Module
Define
precipitation
years
Compute
resulting
flood
hazard
footprints
Calculate
damage
based on
risk item
characteristics
Confidential
Financial
Module
Quantify
financial
loss

29. HIGH QUALITY INPUT DATA
High-Quality, High-Resolution Geospatial
Data is critical to flood modeling
•
•
•
©2014 Risk Management Solutions, Inc.
Confidential
Source resolution for elevation data
improves quickly
Using latest enhanced version of National
Hydrography Dataset (NHD): NHDPlusV2
RMS spent several person-years on QA of
data layers
– Fed findings back to NHDPlus data
providers to help improve their
product

30. EXAMPLE QA TASK
By comparing with Google Earth, corrected misplaced river segment in elevation dataset
Actual path
©2014 Risk Management Solutions, Inc.
Actual path
Confidential

31. HAZARD SIMULATION APPROACH
Tropical Cyclone Precipitation
Precipitation
Simulate the
source of the
flooding:
tropical
cyclone and
non-tropical
cyclone
Non-Tropical Cyclone Precipitation
Rainfall
Runoff
Routing
Defense
Inundation
Understand
how rainfall
enters the
water
systems
Propagate the
water through
major and
minor river
systems
Account for
mitigation
measures and
possibility of
flood defense
failures
Form a
footprint of
saturation
and flooding
Source: cpc.ncep.noaa.gov
©2014 Risk Management Solutions, Inc.
Confidential

32. HAZARD SIMULATION APPROACH
Precipitation
Simulate the
source of the
flooding:
tropical
cyclone and
non-tropical
cyclone
©2014 Risk Management Solutions, Inc.
Rainfall
Runoff
Routing
Defense
Inundation
Understand
how rainfall
enters the
water
systems
Propagate the
water through
major and
minor river
systems
Account for
mitigation
measures and
possibility of
flood defense
failures
Form a
footprint of
saturation
and flooding
Confidential

33. Comparison of 100 year model hazard with FEMA maps - Memphis, TN
RMS
FEMA
©2014 Risk Management Solutions, Inc.
Confidential

34. RMS FLOOD
HAZARD DATA
PRODUCT
Coming
soon!
– Coverage: 48 states & District of Columbia
– All sources of flooding:
o Coastal flooding from storm surge
o Tropical cyclone precipitation
o Non-tropical cyclone precipitation
– Return periods:
o Multiple return periods, 20 years to 1000 years
o Catchments by hydrological regions
– RMS(one) functionality:
o Location-level underwriting, flood zone lookup frequency
and severity with return period and flood depth
o Accumulation management
o Flood hazard visualization
©2014 Risk Management Solutions, Inc.
Confidential

35. Example 200-year return period hazard map
RMS FLOOD
HAZARD DATA
PRODUCT
Fully integrated into
RMS(one)
©2014 Risk Management Solutions, Inc.

36. RMS VS. FEMA: COMPARABLE BUT DIFFERENT
©2014 Risk Management Solutions, Inc.
Confidential

37. RMS VS. FEMA: COMPARABLE BUT DIFFERENT
Return
Period
(years)
FEMA FIRMs
Flood
Extent
Flood
Elevation
20
✓
✓
50
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
100
Flood
Extent
✓
Flood
Elevation
RMS Hazard Data
Product
✓ (BFEs)
250
500
✓
1000
©2014 Risk Management Solutions, Inc.
Confidential

38. RMS VS. FEMA: COMPARABLE BUT DIFFERENT
Component
FEMA FIRMs
RMS Hazard Data
Product
Mapping methodology
Varies by region
Consistent for entire lower
48 states
Geospatial data vintage
(e.g., elevation)
Varies by region
Current
Update frequency
Varies by region,
sometimes > 20 years
Can incorporate changes
quickly
n/a
Uses same event set as
RMS North Atlantic
Hurricane model
Correlation with other
perils
©2014 Risk Management Solutions, Inc.
Confidential

39. Where
have we
been?
NFIP reform will happen,
eventually
Can the private market take on
more of the US flood risk?
Where are
we now?
What’s
changed?
RMS tools already exist…
What’s
coming?
©2014 Risk Management Solutions, Inc.
Confidential
…and more are coming