The Value of Blue Carbon in Galveston Bay, TX

www.Coastal Resilience.org Focus: Addressing increasing threats due to sea level rise and storms by bringing science and action together where nature is part of the solution to reduce risk. “Coastal Resilience is an approach which includes planning frameworks and tools that support decisions to reduce the ecological and socio-economic risks of coastal hazards.”

Coastal Resilience Network The Coastal Resilience Network supports a community of practitioners around the world who are applying the approach, planning methods and tools to coastal hazard and adaptation issues. Gulf of Mexico Resilience Decision Support Tool

CRN Framework: • • • •

Assess risks Identify solutions Take action Measure effectiveness

Habitat Trends in Galveston Bay Area Cypress swamp

?

Saltwater marshes

2,900 ac lost 1992-2002

Sea Grass

Only 518 ac left in 1998

Mangrove

Increase of ~17 %/yr

Lone Star Coastal Alliance

Coastal Protection

Fisheries

Blue Carbon http://www.lonestarcoastal.org/

What Is The Amount Of Carbon Stored And Sequestered By Coastal Marshes for 1-meter Sea-Level Rise Scenario?

What Is The Amount Of Carbon Stored And Sequestered By Coastal Marshes for 1-meter Sea-Level Rise Scenario? 1. Model Introduction

2. Results in Galveston Bay 3. Uncertainty Analysis 4. Conclusion

THE BASICS Blue Carbon • “Coastal blue carbon” is carbon stored and sequestered in coastal vegetation and wetland habitats • These habitats store, or “sink”, carbon in their plant matter and in soils • CO2 can become sequestered away as elemental carbon

THE BASICS Blue Carbon

Co-benefits: Coastal vegetation and wetlands also offer a multitude of other ecosystem services – nursery habitat, recreation, shoreline protection, etc.

BLUE CARBON Why Measure Blue Carbon?

Wetlands and coastal habitats store at least 100 times more carbon than terrestrial plants per unit area

WETLANDS IN GALVESTON BAY

Estuarine wetlands cover approximately 570 km2 of the land in and around Galveston Bay

THREATS TO TEXAS WETLANDS

Sea level is rising at 6.84 mm/yr (70 cm/100yr)

MODELING SCENARIOS

Sea-level rises by 0.4 m in 2050 and 1 m of SLR in 2100

MARSH RESPONSE

Marsh footprint: 2004; 2050; 2100

HOW MUCH CARBON?

CARBON ACCOUNTING Measuring Pools of Carbon ABOVEGROUND BIOMASS

BELOWGROUND BIOMASS

LITTER

STANDING / DEAD CARBON

SOIL

SEDIMENT CARBON

MODEL STEPS How We Measure Coastal Blue Carbon? 1. Quantify carbon stored and sequestered under status quo 2. Quantify changes under alternative management 3. Value the avoided emissions (social or market)

MANGROVE

MARSH

SEAGRASS

OTHER

?

MODEL STEPS How We Measure Blue Carbon Storage and Sequestration? 1 ESTIMATE LAND COVER AT DIFFERENT TIME STEPS

2 BLUE CARBON PREPROCESSOR

3 BLUE CARBON CORE MODEL

4 SYNTHESIZE RESULTS

HOW IT WORKS Pre-Processor

D

D

D

D

D

D

D

D = Disturbance • Low • Medium • High

A A

TIME 1

A

TIME 2

A

A = Accumulation (vegetation/age-specific)

HOW IT WORKS

Half Life = 7.5 yrs

Core Model

coastal development 30%

LOW INTENSITY

TIME 1

TIME 2

DISTURBANCE shrimp aquaculture

70%

HIGH INTENSITY

70%

HOW IT WORKS Valuation •

•

Estimates the economic value of sequestration (not storage) as a function of the amount of carbon sequestered, the monetary value of each ton of sequestered carbon, a discount rate, and the change in the value of carbon sequestration over time. Two categories: social and private

HOW IT WORKS Global Database

Soil content

Decay Rate

Emission Rate

HOW IT WORKS Gulf Database Soil content

Decay Rate

Emission Rate

Salt marsh carbon modeling values from literature

Carbon Storage 2050

Carbon Storage 2100

Sequestration and Emission 2004 – 2050

Sequestration and Emission 2004 – 2050

Sequestration and Emission 2050 – 2100

Sequestration and Emission 2004 – 2100

Bay net emitter by 2100

Sequestration and Emission Marsh Can Not Always Migrate 2004 – 2100

©James G. Titus

Sequestration and Emission 2004 – 2100

More carbon emitted if marsh cannot migrate landward as sea-level rises

Sequestration and Emission Summary

Sequestration and Emission Summary

Sequestration and Emission Summary

• Sequestration possible under moderate SLR • Emissions worse if marshes cannot migrate

Sequestration and Emission Dollar Value of Carbon: Is a Markeyt Possible?

Lucrative market possible if water rises slowly

UNCERTAINTY ANALYSIS Intro

Emission Rate Soil content

Decay Rate

UNCERTAINTY ANALYSIS Methods Accumulation Rate Soil content

Decay Rate

UNCERTAINTY ANALYSIS Methods Accumulation Rate Soil content

Decay Rate

UNCERTAINTY ANALYSIS Methods Accumulation Rate Soil content

Decay Rate

UNCERTAINTY ANALYSIS Results

Most of uncertainty driven by accumulation rate.

CONCLUSION •

Marshes can store hundreds of tons of carbon

•

Marshes can become net emitters of carbon if seas rise too fast

•

InVEST Blue Carbon model excellent choice for such analysis

•

More research needed to improve model parameters

NEXT STEPS • Assess opportunities for integrating blue carbon into state policies along the Gulf of Mexico • Work with partners in exploring opportunities to develop a regional market in Gulf region • Support blue carbon-related research that will lead to increase our understanding of carbon storage and sequestering process • Conserve the capacity of the Gulf coast to storage blue carbon

CARBON (AVOIDED) DAMAGE REFS United States Interagency Working Group on Social Costs of Carbon (U.S. IWGSCC), 2010. Technical Support Document: Social Cost of Carbon for Regulatory Impact Analysis Under Executive Order 12866, Washington, D.C. Available at: http://www.epa.gov/otaq/climate/regulations/scc-tsd.pdf U.S. EPA, 2013. The Social Cost of Carbon, Washington, D.C. Available at: http://www.epa.gov/climatechange/Downloads/EPAactiviti es/scc-fact-sheet.pdf .

THANK YOU

Greg Guannel, Ph.D. (808) 563-0434 [email protected]

Gregg Verutes [email protected]

Jorge Brenner, Ph.D. Associate Director of Marine Science (361) 687-2209 [email protected]