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Sea Level Rise &Implication for Harbors and Marinas
Ronald M. Noble
Looking Into a Warmer Future…
MSLR by 2100 Assuming ΔT < 4° C(Nicholls, et al. 2011 Phil. Trans. Roy. Soc.)
Greenland (+21 ft) and Antarctica (+200 ft) melting will become largest contributor to global MSL rise
Global ≠ Regional MSLR 1992-2009
Fast Rise
No Rise
Global MSLRnot evenly distributed
dynamical effects!
Global MSLR 3.3 mm/yr or 33 cm/cy
Is MSL rise acceleration imminent on west coast?
http://www.aviso.oceanobs.com/
“Reg
ime
Shift
”
Reve
rsal
?
Bromirski, Miller, Flick, Auad, 2011. Dynamical suppression of sea level rise along the Pacific coast of North America: Indications for imminent acceleration, Jour. Geophys. Res. 116(C07005)
Bromirski, Miller, Flick, 2012, North Pacific Sea Level Trends, Eos Trans. AGU, 93(27), 249-256.
Historical Mean Sea Level Trend: San Francisco
Source: NOAA Website
Historical Mean Sea Level Trend: Los Angeles
Source: NOAA Website
“Prediction is very difficult,
especially if it's about the future.”
- Niels ‘Yogi Berra’ Bohr
Global Sea Level Change Prediction (by 2100)
Source: USACE EC 1165-2-212
USACE SLR Guidance: EC 1165-2-212 (2011)
Three SLR scenarios: “Low” SLR rate: using the historical rate of SLR “Intermediate” SLR rate: using modified NRC Curve I “High” SLR rate: using modified NRC Curve III
CO-CAT includes state entities:− Business, Transportation and Housing Agency− Coastal Commission− Dept of Fish and Game− Dept of Parks and Recreation− Dept of Public Health− Dept of Toxic Substances Control− Dept of Transportation− Dept of Water Resources− Environmental Protection Agency− Governor’s Office of Planning and Research− Natural Resources Agency− Ocean Protection Council− Ocean Science Trust− San Francisco BCDC− State Coastal Conservancy− State Lands Commission− State Water Resources Control Board
California Sea-Level Rise Guidance Document
California Climate Action Team (CO-CAT) developed a SLR Guidance based upon NRC 2012 report SLR.
NRC (2012) SLR Report
California Sea-Level Rise Guidance Document
CO-CAT reached agreement on the following policy recommendations for SLR
Time PeriodNorth of
Cape MendocinoSouth of
Cape Mendocino
2000 - 2030-4 to 23 cm
(-0.13 to 0.75 ft)4 to 30 cm
(0.13 to 0.98 ft)
2000 – 2050-3 to 48 cm
(-0.1 to 1.57 ft)12 to 61 cm
(0.39 to 2.0 ft)
2000 – 210010 to 143 cm(0.3 to 4.69 ft)
42 to 167 cm(1.38 to 5.48 ft)
CCC (2013) Draft Sea-Level Rise Policy Guidance
SLR Projects between USACE and CA State
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100
Sea
Leve
l Ris
e fr
om 2
000
(ft)
Year
USACE Low SLR Scenario
USACE Intermediate SLR Scenrio (Modified NRC-I)
USACE High SLR Scenario (Modified NRC-III)
Modified NRC-II
CO-CAT SLR (South of Cape Mendocino)
Cardiff State Beach, 1998
Stinson Beach, 1998
MSL is 20 feet lower!
wave
^
Wave-Driven Runup & Overtopping = Damage
Both private and public infrastructure is and will be at risk!
Waves, Storm Surge & High TidesFlooding & Erosion
December 1982
January 1983
Mission Beach 2010Hs 4 m
Hs 3 m
Beaches and infrastructure are “tuned” to current extremes of ~3m (10 ft) MSL (Bill O’Reilly cartoon)
Extra 0.5-2 m!
“Tuned”
MSLR
SF Bay Area Potentially Exposed to SLR
Over 1 in 6 chance sea level rise + storm surge + tide will overtop + 6 ft by 2100
Implication of SLR: Marina del Rey, California
Src: http://sealevel.climatecentral.org/
Over 1 in 6 chance sea level rise + storm surge + tide will overtop +7 ft by 2100
Implication of SLR: San Francisco, California
Src: http://sealevel.climatecentral.org/
Impact of SLR on Yosemite Slough Wetlands Restoration
Impact of SLR on Yosemite Slough Wetlands Restoration
Impact of SLR on Yosemite Slough Wetlands Restoration
Impact of SLR on Yosemite Slough Wetlands Restoration
Impact of SLR on Yosemite Slough Wetlands Restoration
MSL is 20 feet lower!
Return-Period ‘Creep’
100-yr Maximum Water Level (+5.2 ft MSL) in 2000 becomes 10-yr event in 2017, 1-yr event in 2048, and monthly in 2083
Projections based on MSL rise “central” value +3 ft (2000-2100)
NRC (2012)
Waves, Storm Surge & High TidesFlooding & Erosion
December 1982
January 1983
Mission Beach 2010Hs 4 m
Hs 3 m
Cardiff State Beach, 1998
Stinson Beach, 1998
MSL is 20 feet lower!
wave
^
Wave-Driven Runup & Overtopping = Damage
Both private and public infrastructure is and will be at risk!
Wet
Dry
Mild -but- Variable Climate
• Decades drought
• Decades wet
• Extremes111⁰ - 26 Sep 19633.2” rain - 5 Apr 192625” rain 1940-4126” rain 1883-84
• CA Four “Seasons”QuakeDroughtFireFlood
Dry?
San Francisco Annual Mean Sea Level
60
70
80
90
100
110
1840 1860 1880 1900 1920 1940 1960 1980 2000
cm (M
LLW
)
Sea Level Rise Rates Vary
Regional MSLR rates depend on large-scale atmospheric conditions over North Pacific Ocean
El Niño
-5.4 cm/cy
18 cm/cy
-0.7 cm/cy
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