Disaster Risk Reduction under Current and Changing Climate Conditions

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Disaster Risk Reduction under Current and
Changing Climate Conditions
H. Auld, J. Klaassen, S. Fernandez, S. Cheng, N.
Comer, D. MacIver, S. Eng Environment Canada
Adaptation and Impacts Research Division, Ontario
Region Science Unit
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Global Temperatures Will Continue to Rise
Source IPCC 2007 (WGI/AR4)
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NEED for ACTIONS Mitigation Adaptation
Rates of climate change will be critical and will
vary at regional and local levels
Need mitigation (Kyotos to stabilize climate
buy coping time) adaptation to deal with
inevitable imminent climate changes
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Causes of Rising Natural Disasters
Number of Disasters in EMDAT, 1900 2005
Global Trends in Frequency of Major Natural
Disasters
Adaptation Deficit
Biological
Hydrometeorological
Geological
Source EM-DAT The OFDA/CRED International
Disaster Database. http//www.em-dat.net, UCL -
Brussels, Belgium
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WHAT WE DO KNOW ABOUT CHANGING EXTREMES GLOBALLY?
Regions with disproportionate changes in heavy
and very heavy precipitation during the past
decades compared to changes in the annual and/or
seasonal precipitation (updated from Groisman et
al., 2005).
Evidence exists for increases in both severe
droughts and heavy rains in many regions making
it likely that hydrologic conditions have already
become more intense (IPCC, 2007b).
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WHAT WE DO KNOW ABOUT FUTURE EXTREMES GLOBALLY -
Scientific Agreement

• THE FUTURE
• Increased moisture increased
  precipitation intensity.
• Extreme precipitation changes larger than for
  annual means.
• Increase in mean temperatures - more extreme
  high temperatures and less extreme low
  temperatures.
• More severe droughts
• Stronger hurricanes could become more severe and
  frequent
• Poleward shift of mid-latitude storm tracks,
  with a tendency for more intense but perhaps
  fewer storms

Before end of this century, current 50-year
return period rainfall event could be expected at
least every 25-years
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Natural Disasters in Canada
6 years data!
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WHAT WE DO KNOW ABOUT CHANGING EXTREMES in U.S.?
Studies for the U.S. have found an unambiguous
upward trend in the frequency of heavy to extreme
precipitation events
14 increase in heavy (upper 5) precipitation
20 increase in very heavy precipitation (upper
1)
Number of days exceeding 50 mm/day increasing
Frequencies of extreme events were about as high
at turn of the 20th century as they were at the
end of this century
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WHAT WE DO KNOW ABOUT CHANGING EXTREMES in
CANADA?
Canada warmed at almost twice the rate of global
average
Many regions of Canada tending towards wetter
conditions (45 increase in precipitation in high
Arctic)
By contrast, no discernible trend in frequency of
most extreme precipitation events in Canada
less extreme events increased some parts
But, impacts from precipitation extremes appear
to be increasing???
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Trends in annual mean of daily maximum
temperature1950-2003
Blue and red dots indicate trends significant at
the 5 confidence level. Crosses denote
non-significant trends.
Lucie Vincent, Climate Research Branch, EC
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Trends in Number of Days with Measurable Rainfall
Green and brown dots indicate trends significant
at the 5 confidence level. Crosses denote
non-significant trends.
Eva Mekis, Climate Research Branch, EC
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Trends in Highest 10-Day Rainfalls 1950-2003.
Eva Mekis, Climate Research Branch, EC
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Ontario.. But not evenly
1971-2000

• GETTING WETTER
• NON-LINEAR

WETTER
1961-1990
WETTER
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Disaster Management Planning
Emergency Planning Weather Warning criteria
RISK MANAGEMENT
Hazards for Disaster Planning, Codes and Standards
Warnings Emergency Responses
Recovery Rebuild Forecasts Risk guidance
CRISES MANAGEMENT
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Canadas Climate and its Extremes are Changing
The past will not project the future Climatic
design values based on historical data will
become less and less helpful. However, knowledge
of the past is essential to understanding how
risk is changing.
Trends in the number of days with precipitation ?
95th percentile for period 1950-2003
Eva Mekis, Climate Research Branch, EC
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CLIMATE MODEL PROJECTIONS Probability of daily
extreme precipitation events to increase by AT
LEAST a factor of 2 by end 21st century
Source Environment Canada, CCCma 2007
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CLIMATE and INFRASTRUCTURE VULNERABILITY Small
Increases Escalating Infrastructure Damages
small increases in weather and climate extremes
have the potential to bring large increases in
damages to existing infrastructure
Climate Change could significantly impact
infrastructure, depending on robustness of
existing climatic design values
Source Coleman 2002
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Future Extremes Under Climate Change??
Likely 20 to 30 of seasons in 2080 2099 will
be wetter than the current wettest seasons
Reduction in effective return period event of
todays extremes (i.e. one in 100 year event
expected once every 50 years, on average)
Poleward shift of mid-latitude storms by several
degrees of latitude - tendency for more intense
but perhaps fewer storms
Accelerating trend in storm winds in the Arctic
from 1950-2006
(Fraser Basin Council)
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Projected Rainfall Extremes Under Warm Season
Weather Patterns ( antecedent rainfalls)
Averaged for 4 southern Ontario basins
1st bar 20162035 2nd bar 20462065 3rd bar
20812100
(from Cheng et al)
Greatest increases (30-50) in the heavier
rainfall days (gt25 mm)
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Future Extremes Under Climate Change?? (contd)
Severe summer storms (convective) still debated
increases likely
Increasing frequency of more severe hurricanes
(winds, precipitation) already, increases in
Category 4/5 hurricanes over past 30 years
Wetter and warmer winters have the potential to
bring more severe winter storms (similar results
in Germany) potential for events with heavy
snow loads
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Future Extremes Under Climate Change?? (contd)
Notable snowload roof collapses in winter 2007-08
good probability that ground snow loads
exceeded building code values at some locations
eastern Canada
While snow season length and snow depths will
likely decrease on average, extreme snow depths
and loads from storm events may increase
(increased winter precipitation rain on snow)
In U.S., most regions experience majority of
severe snowstorms in warmer-than-normal winters
(71-80 of all Jan-Feb) AND 61 85 of all
severe snow storms occurred in wetter-than-normal
years.
Similar results for the more severe ice storms
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Projected Changes in Frequency of Freezing Rain
Storm Patterns (Dec-Feb) by 2050s for Toronto
Ottawa
Ottawa
Ottawa
Toronto
Toronto
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Forensic analyses of these 46 severe ice storms
Ontario and Northern U.S.
Study showed risk of major power
outages/emergencies increases when Freezing
rain amounts gt 30 mm
Potential for longer outages more widespread
disasters when Freezing rain amounts gt
40 mm
Current CSA/CEA standards for power lines
defendable if risks of freezing rain storms do
not increase
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What Can We Do Today To Climate Proof for the
Future
No regrets actions (make sense with/without
climate change)
Disaster management planning more emergency
responses needed, disaster risk reduction,
post-disaster reconstruction
Consider hazards, vulnerabilities, critical
infrastructure plan for top weather/climate risks
Weather warning criteria, programs improved
community emergency and planning responses
Learn from the failures.. Multi-disciplinary
forensic studies
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Disaster Management Hazards Information
http//www.hazards.ca
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www.hazards.ca
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HEAT MORTALITY RISKS UNDER CLIMATE CHANGE
Potential Increases in the Number of EXTREME Heat
Alert Days Using Existing Criteria for Extreme
Heat Alert (for Toronto, 90 Prob. of Elevated
Mortalities)
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10.7
9.5
10
7.9
7.4
8
7.0
Number of Days
5.5
6
5.2
3.9
4
current
2.4
2.4
1.7
2080s
2
2050s
2080s
2080s
2080s
2050s
2050s
2050s
0.9
current
current
0
Obs. 2050s 2080s
Obs. 2050s 2080s
Obs. 2050s 2080s
Obs. 2050s 2080s
Montreal
Ottawa
Toronto
Windsor
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What Can We Do Today To Climate Proof for the
Future
Regularly update climate design information in
infrastructure codes standards
Design infrastructure to withstand extremes of
structures lifespan (today and future), where
evidence is consistent
Improved climate science methodologies to better
project future extremes
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And Additional New Actions

• Further adaptation actions, such as
• Incorporate future climate projections into
  codes
• New climate change tools and science, guidance
• Work with lifespan planning diversified
  lifetimes
• More rigorous maintenance potential
  standards???
• New structural materials and engineering
  practices
• Retrofit vulnerable structures Restrict land
  use
• Land use planning, community risk management

WHERE and WHEN to START? PRIORITIES?
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Adaptation using Infrastructure Lifecycle
Timeframes
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Incorporation of Climate Change into
Infrastructure Codes and Standards
Climate change on agenda of National Building
Code of Canada Standing Committee Climatic
Loads Task Group CSA also reviewing implications
for standards
Work underway to identify code climatic values as
well as regions most vulnerable to first changes
Challenge under climate change is to quantify
uncertainties assess climate model performance
specify defensible directions and amounts of
changes to extremes.
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NEW TOOLS and GUIDANCE are being developed
Expanding Climate Change Scenarios Network
(www.cccsn.ca) Regional nodes latest climate
model results from gt 20 international climate
modelling centres
Developing methodologies to project extremes from
climate models (including regional models,
downscaling)
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NEW TOOLS and GUIDANCE
www.cccsn.ca
Climate scenarios from gt 20 modelling centres
worldwide (includes IPCC AR4)
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Dynamical downscaling
Always necessary
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SAMPLE RESULTS Temperature/Precipitation
Change
Scatterplot for Vancouver Grid Cell 2050s
There is a LARGE range of results! Our selection
of appropriate Models/Scenarios is critical
NEW TOOLS and GUIDANCE are being developed
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DUE DILIGENCE REQUIRES THE USE OF MORE THAN ONE
CLIMATE MODEL!!
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SAMPLE RESULTS
Precipitation Vancouver Grid Cell
Median Average 6.8 7.0
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Comparing Baseline Climate Observations at
Vancouver Airport to Model Views of the Baseline
this analysis is best used to reject, versus
accept models

• Some Points
• all the models are too cold on an annual basis
  for the GCM cell
• most models over-estimate annual precip for the
  GCM cell
• this is a particularly difficult environment for
  GCMs and their scale

The perfect model
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Evaluate Climate Model Performance for Past
Climate
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Evaluate Climate Model Performance for Past
Climate
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Disaster Management Planning
Emergency Planning Weather Warning criteria
RISK MANAGEMENT
Hazards for Disaster Planning, Codes and Standards
Warnings Emergency Responses
Recovery Rebuild Forecasts Risk guidance
CRISES MANAGEMENT
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Conclusions

• Under changing climate conditions The past
  will not project the future BUT, knowledge of
  the past is needed to understand how risk is
  changing and to prepare for the future.
• No regrets disaster risk reduction updated
  climatic design values for infrastructure design
  reduce vulnerability to hazards today and an
  effective strategy for reducing future risks.
• Due diligence no regrets actions,
  consideration of several climate model
  projections, consider increasing uncertainties,
  develop new tools.
• Climate changes are happening faster than we
  realize. We need to ADAPT as soon as possible.