Post on 26-Aug-2020
GLOBAL SEA LEVEL RISE AND THE CONSEQUENCES FOR THE BUILT
ENVIRONMENT
5 JUNE 2008
P R O F E S S O R S M A R T I N F I S C H E R A N D B E N S C H W E G L E R
N A T H A N C H A S E , V I V I E N C H U A , D A V I D N E W E L L
Dammed if You Do,Damned if You Don’t
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Inundated areas resulting from 2m SLR
http://flood.firetree.net/
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Introduction
How we got here…
“With a little research and advice from the
professors, putting together a basic dike
design was fairly straightforward… after that,
I was hooked! Countless hours later, the
design process continues…” – Nathan Chase
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Some striking results…
David Newell
Gravel shortages
50+ years for China
65+ years for India
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Some striking results…
Vivien Chua
The first step in reliable engineering design is modeling -we are closer to creating a better world!
Background and Need6
Coastal Development & Ports
Over half of world’s population lives within 200km of the coast (UN, 2001)1
35% coastal pop. growth projected between 1995-2025 (Columbia U.)2
7.187 billion metric tons of seaborne trade in 2006 (AAPA)3
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Sea Level Rise – Fact or Fiction?
Model does not include “future dynamical changes in ice flow”
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Hurricane Katrina Hurricane Andrew
Natural Disasters9
Cyclone Nargis10
Project Overview11
Project Overview
Analyze coastal protection design alternatives
Quantify current/projected capacity of design & construction industry
Model the response using 2D/3D/4D tools and disseminate information
Compare capacity to what is needed
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Limited understanding of DCI capacity
No official statistics for US
Natural disasters can cause significant impact (e.g., Hurricane Katrina/Rita)
Difficulty in compiling global data
Resources are allocated on a regional or national basis e.g. cranes, dredges, steel
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How to Protect Ports
Define the protection strategy and scope
e.g. dikes, levees, landfill for port surface
Develop a “minimum reasonable design” for the scope
Obtain cost data reflective of regional conditions
Compare the design and scope to global data on materials, weather, construction goods and services, etc.
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Why ports?
Fixed infrastructure that cannot be relocated easily
High economic value, easy to measure
Clear baseline of what will be protected
Data availability
Simplifying assumption (difficulties with residential/commercial developments, undeveloped areas, etc.)
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Port Selection16
177 Ports
6 Continents
Population (> 1
million)
Tonnage or
Containers (TEUs)
1 Twenty-foot Equivalent Unit (TEU) is one 20-ft container
(one 40-ft container = 2 TEUs)
Methodology for Case Studies
Goal: evaluate and strengthen project by performing detailed case studies in different regions
Overall procedure:
Site identification
Conceptual design alternatives evaluation
Schematic design development
Incorporation of results in overall project
Tools have been developed to simplify the data collection and design element
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Current Status18
Current Status
Port Characteristics
World’s most important 177 ports, integrated into Google Earth
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Current Status
GIS model “automatically” determines:
- Protection length
- Average protectionheight
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Current Status
Cost and availability/capacity data (US, Asia, Europe) RS Means
UN
Countrywatch
Etc.
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Current Status
Coastal Protection Design tool
Offshore dike, navigation lock, pump station, maintenance dredging
Dike
Lock
Pump
PortOpen OceanDredge
River flooding
Silt
Wave overtopping, scour
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Long Beach Harbor a Case Study
“Manual” design10.5 miles long25m high
- Cost: $1693 million
-Time to construct:21.1 years
“Model” design10 miles long9m high
- Cost: $712 million
- Time to construct:9.7 years
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1 meter sea level rise predicted by 2100!!!25
Sea level record at Golden Gate
Areas at risk in San Francisco Bay
• GIS modeling
• 2D hydrodynamic modeling
1 meter sea level rise
http://flood.firetree.net
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Sacramento-San Joaquin delta
Golden Gate channel
Calibration at NOAA station
Golden Gate (9414290)
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0 2 4 6 8 10 12
x 105
-1
-0.5
0
0.5
1
1.5
2
2.5
Tides at Golden Gate
0 2 4 6 8 10 12 14
x 105
-2
-1.5
-1
-0.5
0
0.5
1
1.5
Tides at Golden Gate
Model
Observations
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What if we do nothing?
• 2D hydrodynamic modeling
Flooding risks
Changes to circulation
patterns
Deterioration of water
quality
Disappearing
habitats/ecosystems
Modifications to sediment
distributions
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Erosion of salt ponds & submerging tidal marshes
Average depth of tidal
marshes and salt ponds =
0.1 m
1 m sea level rise
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Action plan: Partial intrusion
barrage at Golden Gate
Regulate amount of
sea water entering
and leaving the bay
Sea water entering bay as flood tide
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A tidal power barrage?
Estimate of tidal power at Golden Gate
QghP where ρ = density of sea water = 1000 kg/m3, Q = flow rate, g = acceleration due to gravity = 9.81 m2/s, h = tidal amplitude
In a neap-spring cycle,
Max Q = 5000 m3/s
Max h = 2 m
Max P = 1x108W
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Results
-90
-70
-50
-30
-10
10
30
50
70
90
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150
Ports - Overview by Location (LatLon)
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Measuring our Results35
Time to Construct
• Unconstrained (No limitations on materials or resources)
• Constrained by materials
• Constrained by resources (capacity)
• 4D Model Results
Materials
• Raw amountof material required
• Relative amount compared to current production capacity
Cost
• Cost per Shipping Unit• Tonnage• TEUs• Bbl Oil
(Middle East)
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0
2
4
6
8
10
12
14
16
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Nu
mb
er
of
Po
rts
Distribution of Construction Duration by Region
0-2 years
2-5 years
5-10 years
10-20 years
20-50 years
50+ years
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0 20 40 60 80 100 120 140
Australia-New Zealand
Black Sea
Caribbean
China-Korea
SE Asia
India
Japan
Middle East
E Africa
W Africa
Alaska-Hawaii
N America
S America
Mediterranean
N Europe
Years
Time to Construct Defenses by Region
Unconstrained
Capacity Constrained
Material Constrained
Model Constrained
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6%
13%
25%
50%
100%
200%
400%
800%
1600%
3200%
6400%
12800%
Percentage of Current Supply Requiredto Construct Defenses by Region
Cement
Gravel
Sand
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0
1
2
3
4
5
6
7
8
9
Me
tric
To
ns
o
f M
ate
ria
l
Mil
lio
ns
Total Material Demand by Region
Total Cement
Total Gravel
Total Sand
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0
5000
10000
15000
20000
25000
Le
ng
th i
n M
ete
rs
Average Length of Defense per Port by Region
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0
10
20
30
40
50
60
70
Metric Tons of Material per Meter of Length by Region
Cement/Meter
Gravel/Meter
Sand/Meter
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1
2
4
8
16
32
64
128
256
512
1024
2048
Do
lla
rs
Cost to Construct per Shipping Unit per Year
Cost/TEU Cost/Metric Ton Cost/bbl Crude Oil
Google Earth Demonstration
Netherlands
Stanford/S.F. Bay
San Pedro Bay (L.A.)
Port Characteristics
Port Polygons
4D Model
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Future Directions44
Collaborations, Raising Awareness
New collaborations in Netherlands, India, etc.
Stanford Engineering & Public Policy Framework Project: Climate Change and its Impact on the Built Environment
Write journal articles
Make GoogleEarth project data available
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Fall 2008 Undergrad/Grad Course
3 unit CEE course, but need students in economics, public policy, computer science
Focus: Principles & practices for designing a marine construction project, as applied to the Stanford Engineering Framework project Week 1: Introduction, project background, reading on case studies (Netherlands,
Japan, Hurricane Katrina) Week 2: Marine Construction industry: equipment, materials, labor (guest lecturer
from industry) Week 3: Site selection and characterization (guest lecture on coastal development) Week 4-6: Conceptual design (guest lecture) Week 7-9: Schematic design (guest lecture on hydrologic modeling) Week 10: Writing up and presenting results (in class presentations, final reports)
Other elements: intensive collaboration session with students from Delft, Madras/Chennai
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Acknowledgements
Fred Raichlen, California Institute of Technology
Kyle Johnson, Great Lakes Dredge & Dock
Bob Bittner, Ben C. Gerwick Inc.
Andrew Peterman, Walt Disney Imagineering
Chris Holm, Walt Disney Co.
Austin Becker, Rhode Island Sea Grant
Christian Brockmann, Bremen University of Applied Sciences
Prior Stanford students: Mike Dvorak, LakshmiAlagappan, Evridiki Fekka, Elisa Zhang
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Questions?
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