The North American Carbon Program (NACP) Coastal Interim Synthesis Activity: Carbon

and Nutrient Exchanges and Transformations at the Land-Ocean Continuum

Presenter: Steven E. Lohrenz

Department of Marine Science

The University of Southern Mississippi

Steven.Lohrenz@usm.edu

Contributing Authors: Simone Alin (NOAA PMEL), Heather Benway (WHOI), Wei-Jun Cai (UGA), Paula Coble (USF), Peter Griffith (NASA GSFC ), Steven Lohrenz (USM), Jeremy Mathis

(UA-Fairbanks), Galen McKinley (UW-Madison), Ray Najjar (Penn State)

Acknowledgements

• Support provided for this effort from NASA, NSF, NOAA, USGS, and EPA

Overview

• Retrospective of Coastal Carbon Research and Planning Efforts

• Objectives of Coastal Interim Synthesis Activity

• Current Status of Interim Synthesis and Modeling Efforts

Retrospective of Coastal Carbon Research and Planning Efforts

1983-1984 DOE-funded Research

Initiatives to Examine Carbon Cycling in

Continental Margins: SEEP I

1988 Ocean Margins in GOFS: Impact of

Ocean Boundaries on the Interior Ocean (NSF Workshop)

1988-1989 DOE-funded SEEP II

Program: Conclusion that Carbon Largely Remineralized on

Continental Margin

1996 DOE-funded Ocean Margins

Program: Continental Shelf Source or Sink of

CO2?

1992-2008 NSF Coastal Ocean

Processes Program

1999 U.S. Carbon Cycle Science Plan

2002 U.S. JGOFS Synthesis and

Modeling: Publication of Results from OMP

2001 and 2004 RiOMar Workshops to Examine

River-Dominated Ocean Margin Roles

in Carbon and Elemental Cycling

2002 NACP: Include plans for a coastal

network for quantiifying carbon

fluxes

Importance of Coastal Margins in the NACP

“Ocean programs generally focus on open ocean processes, thus missing the CO2 exchange along the ocean margins that can affect the CO2 content of air entering or leaving North America. Coastal upwelling and biological production rates are high in these regions, which also receive large carbon fluxes from rivers. In addition, a large fraction of the ocean's surface waters may acquire the chemical and biological characteristics that control net CO2 exchange via margin processes. Thus, the inf1uence of nearshore processes may extend beyond the geographic boundaries of ocean margins. The North American Carbon Program therefore requiresmarine observations and diagnostic models focused on understanding the role of coastal systems on adjacent ocean basins and on atmospheric CO2 distributions.”

Wofsy and Harris, 2002

Importance of Coastal Margins in the NACP

• Proposed Coastal Carbon Monitoring Network (Wofsy and Harris, 2002, Appendix 3)

http://cdiac.ornl.gov/oceans/Coastal/Coastal_data.html

Importance of Coastal Margins in the NACP

• Need for improved estimates of “North American coastal ocean and continental margin air-sea fluxes, land-ocean and coastal open ocean exchange, and biogeochemical cycling…in order to close the carbon budget over North America”

• Proposed North American Coastal Observing Network

Doney, 2004

Importance of Coastal Margins in the NACP

• Specific coastal objectives included: – “better estimates of air-sea fluxes and

their impact on the CO2 concentrations of continental air masses,

– “estimates of carbon burial and export to the open ocean,

– “elucidation of factors controlling the efficiency of solubility and biological pumps in coastal environments,

– “quantification of the influence of margin biogeochemical processes on the chemical composition of open ocean surface waters, and

– “the development of coupled physical biogeochemical models for different types of continental margins.”

Denning, 2002

Importance of Coastal Margins in the NACP

• “It is very important to quantify carbon fluxes in coastal margins of the area adjacent to the North American continent, lest regional budgets of carbon on land be misattributed.”

• SOCCR (2007)

Importance of Coastal Margins in the NACP

• “Sea level rise and human development are together contributing to losses of coastal wetlands and mangroves and increasing damage from coastal flooding in many areas.”

• “Coasts are projected to be exposed to increasing risks, including coastal erosion, due to climate change and sea level rise. The effect will be exacerbated by increasing human-induced pressures on coastal areas.”

• Coasts are especially sensitive to the effects of climate change

Retrospective of Coastal Carbon Research and Planning Efforts

• Hales, B. et al. [eds.]. 2008. North American Continental Margins: a synthesis and planning workshop. Report of the North American Continental Margins Working Group for the U.S. Carbon Cycle Scientific Group and Interagency Working Group.

Retrospective of Coastal Carbon Research and Planning Efforts:

LOICZ and IGBP Series

Crossland et al. (2005) Liu et al. (2010)

Retrospective of Coastal Carbon Research and Planning Efforts

• OCB Carbon and Biogeochemistry Scoping Workshop on Terrestrial and Coastal Carbon Fluxes in the Gulf of Mexico (Robbins et al., 2009)

http://www.whoi.edu/sbl/liteSite.do?litesiteid=23613&articleId=36027

Current Efforts• Ocean Component of NASA Carbon

Monitoring System– “The quantity of carbon exchanged between

the land and ocean remains an unknown in the global carbon budget.”

Current Efforts• Carbon Cycle Science Plan Update

– New focus on • understanding how natural processes and human

actions affect the carbon cycle, on land, in the atmosphere, and in the oceans,

• determining how policy and management decisions affect the levels of the primary carbon containing gases, carbon dioxide and methane, in the atmosphere, and

• diagnosing how ecosystems, species, and natural resources are impacted by increasing greenhouse gas concentrations, the associated changes in climate, and by carbon management decisions.

LandCarbon Management

Land Use and Land Cover ChangeAgriculture, FertilizerEnergy and BiofuelsPopulation Growth

Water Resource Management

Ocean Carbon Reservoir

Air-Sea ExchangeCarbon Sequestration?

Coastal MarginAir-Sea Exchange

Eutrophication and HypoxiaOcean Acidification

Sea Level Rise ImpactsCoastal Habitat Loss

Water QualityFisheries

Land-Ocean

Exchange

Coastal Ocean Exchange

• Coastal zones are subject to extreme variability and increasing impacts of human activity

Boundary Effects on Continental Air Masses

Overview

• Retrospective of Coastal Carbon Research and Planning Efforts

• Objectives of Coastal Interim Synthesis Activity

• Current Status of Interim Synthesis and Modeling Efforts

Coastal Interim Synthesis Activity Objective

• Stimulate the synthesis and publication of recent observational and modeling results on carbon cycle fluxes and processes along the North American continental margin

• Specifically address important exchanges and transformation of the various carbon forms and nutrients as they are transported from terrestrial ecosystems through river systems to coastal oceans or the Great Lakes

Overview

• Retrospective of Coastal Carbon Research and Planning Efforts

• Objectives of Coastal Interim Synthesis Activity

• Current Status of Interim Synthesis and Modeling Efforts

Coastal Interim Synthesis Activity

• Initiated at July 2008 OCB Summer Workshop

• Five regions with leads– East Coast and Gulf of Maine – Ray Najjar– Gulf of Mexico – Paula Coble– Great Lakes – Galen McKinley– Arctic – Jeremy Mathis– West Coast – Simone Alin

• Wiki: http://coastalcarbon.pbwiki.com/

Key for describing level of uncertainty

Low

Medium

High

East Coast Including Gulf of Maine Najjar et al.

Lohrenz et al., 2010

Gulf of Mexico P. Coble

Chavez et al. 2007, Ch. 15, SOCCR, West Coast pCO2 Time Series

S. Alin

G. McKinley

OCB Carbon Synthesis Workshop

• Dec. 10-11, 2010 San Francisco• Plenary Presentations

– Fluxes from the land to the water (Elizabeth Boyer, Pennsylvania State University)

– Continental shelf-open ocean exchange (Larry Atkinson, Old Dominion University)

– Estuaries and coastal vegetation (Charles Hopkinson, University of Georgia)

– Sediment processes and fluxes (Miguel Goñi, Oregon State University)

OCB Carbon Synthesis Workshop

• Process Breakouts– River-estuary (Bianchi)– Cross-shelf exchange (He)– Sediment Burial (Bergamaschi)– Productivity/Respiration (Lohrenz/Munro)– Air-sea exchange (Salibury)

• Regional Breakouts– East coast (Cai)– Gulf coast (Coble)– West coast (Juranek)– Arctic (Thomas)– Great Lakes (Bootsma)

OCB Carbon Synthesis Workshop

• Databases and web resources (Griffith, NASA GSFC)– NACP Projects database– Search-level metadata in NACP site– CDIAC Ocean data mgmt mission

• Building a database (Chris Osburn, NCSU)– BCO-DMO

• Building a model (Galen McKinley, Univ. of Wisconsin-Madison)

Coastal Synthesis Side Meeting

Coastal Synthesis Meeting

Time: Today at 5:15–6:15 pm

Room: Conti

Open to the Community

Contact: Jeremy Mathis (jmathis@sfos.uaf.edu)

Summary and Conclusions

• The U.S. coastal margins are economically critical regions

• Coastal regions are subject to extreme environmental variability and increasing human impact

• Coastal carbon processes may have a significant impact on the continental carbon budget

• Terrestrial carbon management strategies will have impacts on coastal ecosystems

• Interdisciplinary land-ocean study of the carbon cycle of North America is needed linking watershed and coastal margins on a larger and more interdisciplinary scale than has been done previously

Additional Presentations

Plenary: Managing coastal carbon pools for avoided emission and increased sequestration - an overview of opportunities -- (Jerker Tamelander, Steve Crooks, Dan Laffoley, Dorothee Herr, Carlos Duarte)

Please also visit posters for the NACP: The Linked Carbon and Water Cycles -- The Atmosphere-Land-Ocean Continuum session