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Learn how the Risk Prediction Initiative (RPI) utilizes proxies to improve hurricane landfall probabilities, aiding insurers in assessing risks. Discover the methods, results, and future directions of RPI activities. Proxy data analysis includes storm surges, lake cores, and climate diagnostic proxies.
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Casualty Actuarial Society Hurricane Landfall Probabilities from Proxy Data David Malmquist Risk Prediction Initiative Bermuda Biological Station for Research, Inc.
Preview • Risk Prediction Initiative • Need for Proxies • Proxy Methods and Results • Future Directions
The Goal of the RPI To create links between the climate science and insurance communities so that the science of climate forecasting is available, understandable, and usable by insurers
RPI Information Flow INSURERS Risk Prediction Initiative Government Academia Commercial RiskModelers
X.L. Mid Ocean Re General Re Renaissance Re ACE Limited Centre Solutions Employers Re AIG/IPC Re RPI Corporate Sponsors
RPI Activities • Facilitate working groups • Fund novel research • Develop and distribute research products
Insured Loss terms of coverage Catastrophe Risk Model Hazard landfall probabilitymaximum sustained windspeak wind gustradius of maximum windsforward speed and directiondecay rate latitudelongitudeelevationtopographyconstruction typesurrounding structures Damage physical damagerepair costs
RPI Activities • Facilitate working groups • Fund novel research • extend historical records via proxies • improve hurricane forecasts • climate variability • wind-field dynamics • develop public models • Develop and distribute research products
1 2 3 4 5 ≥ 28.94 28.5-28.9 27.9-28.4 27.2-27.8 < 27.17 74-95 96-110 111-130 131-155 > 155 4-5 6-8 9-12 13-18 > 18 Minimal Moderate Extensive Extreme Catastrophic Saffir/Simpson Scale Pressure(inches) Wind(mph) Surge(ft) Damage
US Tropical Cyclone Damage(1925-1995) $ = Millions of 1995 US dollars Pielke & Landsea, 1997
1900 1950 1990 Tropical Cyclone Observation Land observations Ship logs Aircraft reconnaissance Satellites NOAA, 1993
RPI Funded Research Extend Historical Records Via Proxies
Ocean Lake Hurricane Proxies: Storm Surge Sand BarrierIsland Mud
Lake Core Analysis • Lake Shelby, Alabama • 3.2-3.0, 2.6, 2.2, 1.4, 0.8 ka • ~ 600 year return period • Category 4 or 5 sand layers 0 100 200 300 400 500 Depth (cm) data from K.-b. Liu
H216O > 99.7% H218O ~ 0.2% A Climate Diagnostic Proxy:Oxygen Isotopes Mean Sea Water
Texas Summer Precipitation 1985-92 Summer Rain Tropical Cyclones n = 208 Rainfall Events -15 -13 -11 -9 -7 -5 -3 -1 1 Oxygen Isotope Values Lawrence & Gedzelman, 1996
Proxy Tape Recorder 10 8 6 4 2 18O 0 -2 - 2.93‰ -4 -6 -8 - 9.35‰ -10 Time
Growth of Cave Deposits precipitation dissolution H2O + CO2 + CaCO3 <––> Ca++ + 2HCO3- stalactite column stalagmite
Stalagmite Cross-Section Fidelity Sampling Interval 18O
What are the Potential Proxy Signals? • Within-tree differences in ring width • Between-tree differences in ring width • local (cohort) • regional (intersite) • Isotopic Signals
Hurricane Camille (1969) Mississippi Louisiana Slidell Pass Christian
Single -Tree Analysis Hurricane Wind
Single -Tree Analysis 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Hurricane Camille Standardized Ratio 1990 1950 1960 1970 1980 Doyle & Gorham, 1996
Cohort Analysis Hurricane Wind A B B A
1950 1960 1970 1980 1990 Cohort Analysis 6 5 4 3 2 1 0 Hurricane Camille Growth Ratio Doyle & Gorham, 1996
Inter-Site Analysis MS LA LA MS
1950 1960 1970 1980 1990 Inter-Site Analysis 7 6 5 4 3 2 1 0 Hurricane Camille Growth Ratio Doyle & Gorham, 1996
Hurricane Proxies: U.S. Geography Lake cores Tree-rings Caves
Facilitate working groups • Fund novel research • Develop and distribute research products • http://www.bbsr.edu/rpi/