Transcript Slide 1

Climate Change / Adaptation
Jerry W. Webb, P.E., D.WRE
Principal Hydrologic & Hydraulic Engineer
Hydrology, Hydraulics & Coastal Community of Practice Leader
US Army Corps of Engineers, Headquarters
[email protected]
Dam Safety Workshop
Brasília, Brazil
20-24 May 2013
Corps of Engineers
BUILDING STRONG®
US Army Corps of Engineers Civil Works
Missions: Water Resources Management
Hydropower
Emergency
Management
Ecosystem
Restoration
Recreation
Flood and
Coastal
Storm Risk
Reduction
Regulatory
Water
Supply
Navigation
NAVIGATION
2
Climate change
mitigation is about
Climate change
adaptation is about
USACE Climate Adaptation
Mission:
To improve resilience and
decrease vulnerability to the
effects of climate change
and variability
Bill Byrne, MA F&W
USACE Climate Adaptation Policy
June 2011
 Integrate climate change
adaptation planning and actions
into USACE missions, operations,
programs, and projects
 Use the best available and
actionable climate science and
climate change information at
appropriate level of analysis
 Consider climate change
impacts when undertaking longterm planning, setting priorities,
and making decisions
http://www.corpsclimate.us/adaptationpolicy.cfm
Climate Change, Extreme Events and
Water Infrastructure
 Extreme events and
increasing variability
increase water
resources vulnerability
► Public
health and safety
► Economic development
► Environmental
sustainability
National Geographic
Extremes and Surprises Add Complexity
 “… the biggest issue is not a failure to envision
events that may be surprising.”
 “It is a failure to decide which ones to act upon, and
to what degree.”
 “That failure results, at least partially, from the fact
that there is no systematic mechanism in place…. to
help decide which events to act upon aggressively,
which to treat to a lesser degree, and which to
ignore, for the time being.”
US DoD Defense Science Board: Capability Surprises
7
Water Resources Infrastructure Long
Service Life and Long Lead Time
Increasing Severity of Climate Impacts
Engineering and Design
Infrastructure Service Life
Planning
In Service
Construction
Infrastructure planned and built with past climate and weather in mind may not be
adequate for future resilience and operation.
0
10
20
30
40
50
60
Years
After United States Ports: Addressing the Adaptation Challenge, Mr. Mike Savonis
70
80
90
100
DISASTER
Adaptation to Climate Change and
Extreme Events is a Continuum
Analyses,
Operational
Measures,
Anticipatory
Engineering
Preparedness,
Response,
Recovery
Policy,
Structural
Measures, PostEvent
Adaptation
Severe Weather –
Midwest
Mar 2012
Key 2011/2012 Responses
FEST Deployments
Jan – Mar 2011 &
OEF/OND
Japan EQ & Tsunami Mar 2011
Queensland, Australia Christchurch, New Zealand
Flood - Jan 2011
Earthquake - Feb 2011
Kootenai River Basin
2012
Kootenai River, 8.96 million acres, 2 countries, 2 states
75% in BC, 21% in MT, 6% in ID
Northeast Snow Storm
Oct 2011
Derecho Storms
JUN-JUL 12
Hurricane
Irene
Aug 2011
Queens Bay at Kooteney Lake
Corra Linn Dam
Tropical
Storm Lee
Sep 2011
Koocanusa Reservoir
To the Columbia River
MS Floods
May 2011
Bonners Ferry
Libby Dam
Souris River
Flood
Jun/Jul 2011
2012 Drought
AL & MS Tornados
Apr 2011
Joplin, MO
Tornado - June
2011
RRCC VII
Joplin, MO (RFO)
Fort Crowder
Logistics Point
MO River
Flood
Jun/Jul 2011
Pakistan Siachen
Glacier SME
Support
April 2012
Duluth, MN Flood
Thailand Flood - Nov 2011
Quick Review of Using
Scenarios in Support of
Climate Change Analyses
With Emphasis on Sea-Level
Change
Changing Paradigms:
From Equilibrium to Dynamic
 Hurricane Katrina
►
Internal and external reviews
following Hurricane Katrina (IPET,
HPDC, ASCE, National
Academies, and others)
demonstrated that we need to
incorporate new and changing
conditions, both foreseen and
surprise, into USACE projects and
programs
 Stationarity
►
Climate change undermines a
basic assumption that historically
has facilitated management of
water supplies, demands, and
risks.’ Milly et al 2008
Fundamental Change in Approach to Future
Conditions
 Historically, we identified a single most likely future
condition and based our without-project (baseline)
analyses on this condition
 Now, we understand that there can be multiple plausible
futures, each representing a different combination of
physical processes, social and political values, and
economic conditions, among other factors
 In particular, for hydrology, we can no longer rely on the
assumption of stationarity, where statistical properties
of hydrologic variables in future time periods are
assumed to be similar to past time (i.e., future variation
in the same range as in the past)
Universe of Futures
Carter et al (2007)
“We need to research all the
potential outcomes, not try to
guess which is likeliest to
occur.”
“Probability in the natural
sciences is a statistical
approach relying on repeated
experiments and frequencies of
measured outcomes, in which
the system to be analysed can
be viewed as a ‘black box’.
Scenarios describing possible
future developments in society,
economy, technology, policy
and so on, are radically
different.”
Why Scenarios?
 Scenarios are appropriate when uncertainties are large,
the consequences are significant, and outcomes cannot
be bounded
 Scenarios are intended to illuminate potential
vulnerabilities to the range of outcomes
 Once we've identified how and where we are vulnerable,
we can evaluate whether we are equipped to deal with
the vulnerabilities
 Next, we address trade-offs between costs and other
effects under each option to address vulnerabilities
 Probabilities simplify the math, but don't really help us
to explore these kinds of issues – instead, probabilities
make it easy for us to ignore these issues
Why Scenarios for Sea-Level Change?
 Remember, scenarios are appropriate when
uncertainties are large, the consequences are
significant, and outcomes cannot be bounded
 Sea level change (and more broadly, broader climate
change) meets the first and last of these three
conditions.
 For the second condition, we use sensitivity testing to
determine the potential consequence of sea-level
change, and the sensitivity test guides our scope of
study and the rigor of the scenario analysis
EC 1165-2-211 Incorporating Sea Level Change
Considerations in Civil Works Programs
 Three estimates of future SLC must be calculated for all Civil
Works Projects within the extent of estimated tidal influence:
►
►
►
Extrapolated trend
Modified NRC Curve 1
Modified NRC Curve III
 These curves are scenarios
based on different
assumptions about
processes and causes
without specific
attributions of likelihood
 As a result, the scenarios
used in the EC represent
multiple plausible futures
physical
Comparison of EC 1165-2-211,
IPCC, and Other Recent Research
Does not include changes in
sea level resulting from
changes in the large ice
sheets covering Greenland
and Antarctica
~ EC
Examples of Climate Change
Adaptation
Example: Mississippi Watershed Extremes
40%
Upper Mississippi and
Missouri Rivers
Combined
60%
Ohio River
Flow Contribution to Lower Mississippi River
Mississippi River Extremes
• Flood of 2011 tested system
• Huge volume, long duration, snowmelt and rainfall
• System performed as designed
• Flood risk reduction systems were operated at their
maximum capacity, some for the first time ever
• Design demonstrated incredible foresight
• Drought of 2012 tested system again
• Impacts to navigation, water supply, recreation, energy
production
• 2011 and 2012 highlighted resilience to extreme
events
Columbia River Treaty
2014/2024 Climate Change
Impact Studies
Projected Increases in Annual
Temperature
2080s
+5.3ºF
(2.8-9.7ºF)
2040s
2020s
+3.2ºF
(1.6-5.2ºF)
+2.0ºF
(1.1-3.4ºF)
°C
°F
Choice of emissions scenario
matter more after 2040s
Mote and Salathé, 2010
* Compared with 1970-1999 average
Projected Changes in Annual
Precipitation
* Compared with 1970-1999 average
Changes in annual precipitation averaged over all models
are small but some models show large seasonal changes,
especially toward wetter autumns and winters and drier
summers.
Mote and Salathé, 2010
Trends in
Fractional
Streamflow
As the West warms,
spring flows rise
and summer flows
drop
Stewart IT, Cayan DR,
Dettinger MD, 2005:
Changes toward earlier
streamflow timing across
western North America, J.
Climate, 18 (8): 1136-1155
Changes in Simulated April 1
Snowpack
Canadian and U.S. portions of the Columbia River basin
(% change relative to current climate)
20th Century Climate
“2020s” (+1.7 C)
-3.6%
-21.4%
April 1 SWE (mm)
“2040s” (+ 2.25 C)
-11.5%
-34.8%
Temperature thresholds for
coldwater fish in freshwater
• Warming temperatures will increasingly stress coldwater
fish in the warmest parts of our region
– A monthly average air temperature of 68ºF (20ºC) has been used as an
upper limit for resident cold water fish habitat, and is known to stress Pacific
salmon during periods of freshwater migration, spawning, and rearing
+1.7 °C
+2.3 °C
The Dalles Regulated,
Median year at The Dalles
Wet has
more
volume
Nov-May
Peak is
slightly
earlier, but
similar
Base has
noticeable
more volume
in Jul-Sep
Average HydSim Outflows at the Dalles
The Dalles - Average Outflow - All Years
400000
Early April drop attributed to
reduction in Arrow outflows as
defined by Treaty operations
350000
300000
Qout
250000
Note significant
increase in winter
flows
200000
Note reduced
summer flows
150000
100000
50000
0
Oct
Nov
Dec
Jan
Feb
Base 2A-TC-45
Mar
Apr
Dry Case
May
Jun
Wet Case
Jul
Aug
Sep
Flood Control vs. Refill
 Balance between flood protection and reliability of refill
is crucial in the Columbia Basin.
 As peak flows move earlier in the year
► flood evacuation schedules may need to be revised
• To protect against early season flooding
• To begin refill earlier to capture the (smaller) spring
freshet.
 Model experiments (see Payne et al. 2004) have shown
that moving flood evacuation two weeks to one month
earlier in the year helps mitigate reductions in refill
reliability associated with streamflow timing shifts.
Payne, J.T., A.W. Wood, A.F. Hamlet, R.N. Palmer, and D.P. Lettenmaier,
2004, Mitigating the effects of climate change on the water resources of the
Columbia River basin, Climatic Change, Vol. 62, Issue 1-3, 233-256
Implications for Transboundary Agreements
 Canadian Snowpack is less sensitive to warming then in
U.S. portion of Columbia basin
► Streamflow timing shifts will also be smaller in Canada.
 Over the next 50 years or so, Canada will have an
increasing fraction of the snowpack contributing to
summer streamflow volumes in the Columbia basin.
 These differing impacts in the two countries have the
potential to “unbalance” the current coordination
agreements, and will present serious challenges to meeting
instream flows on the U.S. side.
 Changes in flood control, hydropower production, and
instream flow augmentation will all be needed.
 Long-range planning is needed to address these issues.
Other Implications of Climate
Change
Bulletin 17B Revision
• Previous Wording for “Climatic
Trends:”
“There is much speculation about
climatic changes. Available evidence
indicates that major changes occur in
time scales involving thousands of
years. In hydrologic analysis it is
conventional to assume flood flows are
not affected by climatic trends or cycles.
Climatic time invariance was assumed
when developing this guide.”
►
Bulletin 17B Revision
• Revised Wording for Climate Paragraph:
“There is much speculation about changes in flood risk
over time. Available evidence indicates that major changes
may be occurring over decades or centuries. While time
invariance was assumed when developing this guide, where
changes in climate and flood risk over time can be accurately
quantified, the impacts of such changes should be
incorporated in frequency analysis by employing timevarying LP3 parameters or using other appropriate and
statistically justified techniques. All such methods need to be
thoroughly documented and justified.”
►
Dam Safety Implications
 Changes to storm
types and
magnitudes
 Changes to runoff
characteristics
 Changes to
calculations of
Probable Maximum
Precipitations – Dew
Point alterations
Example Effects from Regional
Precipitation Shifts
2050 A1FI Drought
Index
IPCC AR4 model CCSM3
► South
regions drier
during growing
seasons, reducing
agricultural productivity
► Extreme
storms affect
Central America and
the Caribbean more
than elsewhere
► Shifts
in wet/dry
seasonality
Graphic from Ganguly et al., (ORNL) produced for backing the QRD 2009.
http://www.ornl.gov/knowledgediscovery/QDR/
--
LEARNING OBJECTIVES
 Using the course manual, references and lecture
notes, the student will be able to understand
hydrologic and hydraulic aspects of dam safety
program. After this presentation, the student will
be familiar with concepts, terminology and interrelationships between hydrologic, hydraulic and
water management considerations essential in
the engineering analysis associated with the
administration of the USACE Dam Safety
program.
QUESTIONS