Sea Level Rise & Bay Area Predictions: A Comprehensive Review A Senior Project by Lee Jasperse , SVHS Senior

A Senior Project

by Lee Jasperse , SVHS Senior

Why should you care? More than 600 million people live in low-lying coastal zones worldwide. 1 meter sea level rise would inundate the San Joaquin Delta, areas of Napa, Palo Alta, Alameda, & San Francisco. Most newly vulnerable areas are developed areas.

More than 600 million people live in low-lying coastal zones worldwide.

1 meter sea level rise would inundate the San Joaquin Delta, areas of Napa, Palo Alta, Alameda, & San Francisco.

Most newly vulnerable areas are developed areas.

What will be discussed? Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

What will be discussed? Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

What’s the difference? Eustatic SLR: the global mean sea level rise. Caused by temperature changes, melting glaciers, etc. 195 mm from 1870 - 2000 Local SLR: Localized, often short term, increases in water levels. Caused by tides, storm conditions, El Nino, floods, etc.

Eustatic SLR: the global mean sea level rise.

Caused by temperature changes, melting glaciers, etc.

195 mm from 1870 - 2000

Local SLR: Localized, often short term, increases in water levels.

Caused by tides, storm conditions, El Nino, floods, etc.

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Global Sea Level Rise SLR acceleration of .013 ± .0006 mm yr -2

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Left: Est. contributions to SLR from 1993-2003 (IPCC). Above: Est. contributions to SLR from 1996-2006 (Meier et al. 2007).

Thermal Expansion Water expands as it’s heated. Contributed ~25% of SLR from 1955-1995 Contributed ~50% of SLR from 1993-2003 Projected to contribute more than 50% to SLR between 2008 and 2100. IPCC TAR estimates 1990-2100 contribution to be 110 - 430 mm.

Water expands as it’s heated.

Contributed ~25% of SLR from 1955-1995

Contributed ~50% of SLR from 1993-2003

Projected to contribute more than 50% to SLR between 2008 and 2100.

IPCC TAR estimates 1990-2100 contribution to be 110 - 430 mm.

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Contributions from ice loss Present day contributions From Meier et al. (2007) & Monga Bay

Future contributions from ice loss Total contributions from present to 2100 From Meier et al. (2007)

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Glaciers & Ice Caps Historic contribution 1961-2003: 0.5 ± 0.18 mm / year 1993-2003: .77 ± 0.22 mm/year 20% of observed rise by 1998 Future Contribution Present - 2100: 240 ± 128 mm Only 35% of volume will be depleted by 2100.

Historic contribution

1961-2003: 0.5 ± 0.18 mm / year

1993-2003: .77 ± 0.22 mm/year

20% of observed rise by 1998

Future Contribution

Present - 2100: 240 ± 128 mm

Only 35% of volume will be depleted by 2100.

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Greenland Potential SLR contribution: 7.2 meters Historic contribution 1993-2003: 0.2 ± 0.1 mm / year Future Contribution Present - 2100: 240 ±128 mm Possibly double or triple current estimates (Csatho 2008, Carlson et al. 2008).

Potential SLR contribution: 7.2 meters

Historic contribution

1993-2003: 0.2 ± 0.1 mm / year

Future Contribution

Present - 2100: 240 ±128 mm

Possibly double or triple current estimates (Csatho 2008, Carlson et al. 2008).

Contributing Global Factors Thermal Expansion Ice Loss Glaciers & Ice Caps Greenland Antarctica

Thermal Expansion

Ice Loss

Glaciers & Ice Caps

Greenland

Antarctica

Antarctica Historic contribution 1993-2003: 0.2 mm / year Future Contribution West Antarctic Ice Sheet: 120 ± 50 mm East Antarctic Ice Sheet: -56 ± 40 mm

Historic contribution

1993-2003: 0.2 mm / year

Future Contribution

West Antarctic Ice Sheet: 120 ± 50 mm

East Antarctic Ice Sheet: -56 ± 40 mm

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

IPCC Prediction Depending on the greenhouse gas emissions scenario, SLR could range from .18 to .59 meters. Estimates are considered very conservative. Does not include contributions from ice sheet flow.

Depending on the greenhouse gas emissions scenario, SLR could range from .18 to .59 meters.

Estimates are considered very conservative.

Does not include contributions from ice sheet flow.

Examining the paleoclimate Models underestimate contributions from the Greenland & Antarctic Ice Sheets. Examine historical sea level rise and deglaciation. Overpeck: 1+ meter of SLR by 2100, and committed to 4-6 meters over the next few hundred years. Carlson et al & Overpeck et al

Models underestimate contributions from the Greenland & Antarctic Ice Sheets.

Examine historical sea level rise and deglaciation.

Overpeck: 1+ meter of SLR by 2100, and committed to 4-6 meters over the next few hundred years.

A simpler method... Computer modelling has underestimated observed SLR. “Semi-Empirical Approach”: Correlates long term SLR with global temperature. Closely matches observed SLR. Grinsted: .7 - 1.1 meters of SLR for B1 emission scenario. 1.1 - 1.6 meters for the A1F1 scenario. Rahmstorf & Grinsted

Computer modelling has underestimated observed SLR.

“Semi-Empirical Approach”: Correlates long term SLR with global temperature.

Closely matches observed SLR.

Grinsted: .7 - 1.1 meters of SLR for B1 emission scenario. 1.1 - 1.6 meters for the A1F1 scenario.

Uncertainty Low Uncertainty: Thermal Expansion High Uncertainty: Greenland & Antarctica Ice sheet flow & ice dynamics Sea levels act as positive feedback, destabalizing ice sheets Increased # of suraglacial lakes

Low Uncertainty:

Thermal Expansion

High Uncertainty:

Greenland & Antarctica

Ice sheet flow & ice dynamics

Sea levels act as positive feedback, destabalizing ice sheets

Increased # of suraglacial lakes

Environmental Impacts A collapse of the Western Antarctic Ice Sheet would shift Earth’s rotational axis 500 meters, shifting water globally towards North Americ and the southern Indian Ocean. Arctic animals may go extinct (seals, polar bears). Salt water intrusion in coastal habitats and aquifers. Marshes and wetlands will be inundated. 14,000 sq. miles would be inundated in the US.

A collapse of the Western Antarctic Ice Sheet would shift Earth’s rotational axis 500 meters, shifting water globally towards North Americ and the southern Indian Ocean.

Arctic animals may go extinct (seals, polar bears).

Salt water intrusion in coastal habitats and aquifers.

Marshes and wetlands will be inundated.

14,000 sq. miles would be inundated in the US.

Social Impacts Coastal and island populations will be displaced. 634 million people live in low-elevation coastal zones. Island nations may be entirely submerged. Kiribati

Coastal and island populations will be displaced.

634 million people live in low-elevation coastal zones.

Island nations may be entirely submerged.

Kiribati

Economic Impacts $1,182 billion (1995 US dollars) will be lost solely from global wetland loss. Global warming may result in a 20% cut in global GDP.

$1,182 billion (1995 US dollars) will be lost solely from global wetland loss.

Global warming may result in a 20% cut in global GDP.

Sea Level Rise in the Bay Area

Oakland Airport

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Contributing Factors Mean SLR (follows global trend) Water level factors Spring tides Storm Surge Barometric effect: -1 atm = +1 inch SLR El Nino

Mean SLR (follows global trend)

Water level factors

Spring tides

Storm Surge

Barometric effect: -1 atm = +1 inch SLR

El Nino

Contributing Factors Mean SLR (follows global trend) Water level factors Spring tides Storm Surge Barometric effect: -1 atm = +1 inch SLR El Nino Erosion/Deposition dynamics

Mean SLR (follows global trend)

Water level factors

Spring tides

Storm Surge

Barometric effect: -1 atm = +1 inch SLR

El Nino

Erosion/Deposition dynamics

Tides Vary around mean sea level on a daily time scale.

Vary around mean sea level on a daily time scale.

Tides Also vary around a monthly timescale.

Also vary around a monthly timescale.

Tides Tides are highest during spring tides — tides that rise the highest and fall the lowest.

Tides are highest during spring tides — tides that rise the highest and fall the lowest.

Tides Tides are the largest component of sea level change, and are the most predictable.

Tides are the largest component of sea level change, and are the most predictable.

Contributing Factors Mean SLR (follows global trend) Water level factors Spring tides Storm Surge Barometric effect El Nino Erosion/Deposition dynamics

Mean SLR (follows global trend)

Water level factors

Spring tides

Storm Surge

Barometric effect

El Nino

Erosion/Deposition dynamics

Storm Surge & Barometric Effect Combination of persisent winds and low pressure. Strong surface winds causes water levels to increase at the downward shore. Wind whips can cause stronger waves with greater momentum. Low atmospheric pressure increases sea level (-1 atm = +1 inch). In the SF Bay, maximum effect is 1 meter SLR. Impact rarely exceeds .3 m. “ Wave induced surge on a beach... can reach 1.5 m.” (Cayan et al )

Combination of persisent winds and low pressure.

Strong surface winds causes water levels to increase at the downward shore. Wind whips can cause stronger waves with greater momentum.

Low atmospheric pressure increases sea level (-1 atm = +1 inch).

In the SF Bay, maximum effect is 1 meter SLR.

Impact rarely exceeds .3 m.

“ Wave induced surge on a beach... can reach 1.5 m.” (Cayan et al )

Contributing Factors Mean SLR (follows global trend) Water level factors Spring tides Storm Surge Barometric effect: -1 atm = +1 inch SLR El Nino Erosion/Deposition dynamics

Mean SLR (follows global trend)

Water level factors

Spring tides

Storm Surge

Barometric effect: -1 atm = +1 inch SLR

El Nino

Erosion/Deposition dynamics

El Nino Sustained sea surface temperature anomalies >5ºC Leads to storm conditions and abnormally high tides. Ex: El Nino caused tides in San Francisco to be ~2 feet higher than normal in the early winter months of 1997 & 1998. Local thermal expansion

Sustained sea surface temperature anomalies >5ºC

Leads to storm conditions and abnormally high tides.

Ex: El Nino caused tides in San Francisco to be ~2 feet higher than normal in the early winter months of 1997 & 1998.

Local thermal expansion

Contributing Factors Mean SLR (follows global trend) Water level factors Spring tides Storm Surge Barometric effect: -1 atm = +1 inch SLR El Nino Erosion/Deposition dynamics

Mean SLR (follows global trend)

Water level factors

Spring tides

Storm Surge

Barometric effect: -1 atm = +1 inch SLR

El Nino

Erosion/Deposition dynamics

Erosion/Deposition Dynamics Sediment from erosion builds up. Changes spatial component of land.

Sediment from erosion builds up.

Changes spatial component of land.

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Predictions Likely 1.4 m mean SLR in the Bay Area. Flooding occurs when sea level extremes occur — spring tides, low atmospheric pressure & storm events, and El Nino occur simultaneously. San Francisco Bay appears sensative to sea level changes — the occurrence of extremes has increased 20-fold since 1915.

Likely 1.4 m mean SLR in the Bay Area.

Flooding occurs when sea level extremes occur — spring tides, low atmospheric pressure & storm events, and El Nino occur simultaneously.

San Francisco Bay appears sensative to sea level changes — the occurrence of extremes has increased 20-fold since 1915.

Predictions As mean sea level rises & severe weather conditions potentially become more severe, the risk of large scale flooding increases. Projected monthly SF sea level anomolies from the mean sea level. From Cayan et al. (2007)

As mean sea level rises & severe weather conditions potentially become more severe, the risk of large scale flooding increases.

Projected monthly SF sea level anomolies from the mean sea level.

Predictions The amount of land vulnerable to flooding increases significantly. Most newly vulnerable land are the Central and South Bay’s developed areas.

The amount of land vulnerable to flooding increases significantly.

Most newly vulnerable land are the Central and South Bay’s developed areas.

Uncertainty Mean global sea level. Sediment erosion, supply, and deposition. Levee failure. Frequency of storm surge / El Nino events.

Mean global sea level.

Sediment erosion, supply, and deposition.

Levee failure.

Frequency of storm surge / El Nino events.

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Implications

Environmental Impacts Wetlands and grasslands are among those at greatest risk of flooding. Saltwater will flow into the Sacramento-San Joaquin River Delta, from which fresh water is pumped to about 67% of Californians. It will also intrude on aquifers. 22 industrial and municipal wastewater systems are at risk of inundation. Shoreline dumps and military installations threatened by a rising bay could leak biological and chemical contaminents into the bay.

Wetlands and grasslands are among those at greatest risk of flooding.

Saltwater will flow into the Sacramento-San Joaquin River Delta, from which fresh water is pumped to about 67% of Californians. It will also intrude on aquifers.

22 industrial and municipal wastewater systems are at risk of inundation.

Shoreline dumps and military installations threatened by a rising bay could leak biological and chemical contaminents into the bay.

Impacts in terms of land cover From Noah Knowles, USGS

Image from Noah Knowles, USGS

Social Impacts Those who live in parts of Corte Madera, San Rafael, Hayward, Newark, Marin (Sausalito), San Francisco, and the Silicon Valley shoreline would likely be displaced. 480,000 people at risk from SLR along California coast. 9600 people vulnerable in Sonoma County with a 1.4 m mean SLR. Disproportionately high impact on low income families in Sonoma.

Those who live in parts of Corte Madera, San Rafael, Hayward, Newark, Marin (Sausalito), San Francisco, and the Silicon Valley shoreline would likely be displaced.

480,000 people at risk from SLR along California coast.

9600 people vulnerable in Sonoma County with a 1.4 m mean SLR.

Disproportionately high impact on low income families in Sonoma.

Economic Impacts High cost due to wetland loss ($6-$30 thousand per acre lost). Substantial damage to infrastructure: 25.9 miles of vulnerable roads and highways in Sonoma County San Francisco and Oakland airports Cost of flooding of buildings & houses along California coast estimated at $100 billion. $.48 billion in Sonoma County. San Francisco and Oakland airports

High cost due to wetland loss ($6-$30 thousand per acre lost).

Substantial damage to infrastructure:

25.9 miles of vulnerable roads and highways in Sonoma County

San Francisco and Oakland airports

Cost of flooding of buildings & houses along California coast estimated at $100 billion.

$.48 billion in Sonoma County.

San Francisco and Oakland airports

Roadmap Eustatic vs. Local sea level rise Eustatic sea level rise Contributions to global mean sea level rise Global mean sea level rise projections Bay Area sea level rise Contributions to localized flooding Flooding predictions in the Bay Area Implications Next Steps

Eustatic vs. Local sea level rise

Eustatic sea level rise

Contributions to global mean sea level rise

Global mean sea level rise projections

Bay Area sea level rise

Contributions to localized flooding

Flooding predictions in the Bay Area

Implications

Next Steps

Next Steps Study in greater detail SLR’s spatial impact. Prepare for sea level rise: Revamp levies & walls ($14 billion California-wide investment) Perform a cost/benefit analysis to determine which areas to protect most heavily. Restore buffers.

Study in greater detail SLR’s spatial impact.

Prepare for sea level rise:

Revamp levies & walls ($14 billion California-wide investment)

Perform a cost/benefit analysis to determine which areas to protect most heavily.

Restore buffers.

Thank You!