Coastal Processes and Biogeochemical Fluxes at the Land-Ocean by yurtgc548


									       Coastal Processes and
    Biogeochemical Fluxes at the
       Land-Ocean Interface
                  William Balch
   Bigelow Laboratory for Ocean Sciences, W.
               Boothbay Harbor, ME
 (With help from: George Aiken (USGS), Andrew
Barnard (WETLabs), Francisco Chavez(MBARI),
  Marjorie Friederichs (VIMS), Tom Huntington
  (USGS), Steve Lohrentz (UMass Dartmouth),
Antonio Mannino (NASA Goddard), Collin Roesler
  (Bowdoin College), Joe Salisbury (Univ. NH),
Crystal Schaaf (UMass Boston), Menghua Wang
    (NOAA NESDIS); Huije Xue (Univ. Maine)
       Descriptions of land-to-sea
       connections are not new…
• “With the concentration of dissolved nitrogen compounds
  probably at least twice as high in river water as in the
  sea water of the gulf, the freshening of the latter, which
  is caused in spring by river freshets, is probably
  accompanied by a considerable increase in the
  concentration of nitrogen in the coastal zone over the
  values obtaining there in winter, with the alteration
  greatest near the mouths of the larger rivers and along
  the zones where their discharges have the greatest
  effect on salinity”
         Henry Bigelow; Plankton of the offshore waters of
  the Gulf of Maine; p. 470; 1924
 Gordon Riley contemplating factors
  that affect the coastal zone over
        half a century ago…
• “What is the role of freshwater drainage? How damaging
  are the pollution effects? Does land drainage enrich the
  coastal area, or is this effect insignificant compared with
  the transport of nutrients by physical oceanographic
  processes? What effect do silt and bottom sediments
  have on the transparency of the water and how seriously
  do they influence phytoplankton production and animal
  Gordon Riley, “Oceanography of Long Island Sound, 1952-1954”,
  1956. Bulletin of the Bingham Oceanographic Collection, p. 10,
Carbon transfer from sea-to-land- Deep
Water Horizon oil spill. Nothing focused us
more on the importance of coasts than that

                             MODIS Terra 5-24-10
 Many programs have focused on the
land-sea boundary. To name a few…
• Shelf-Edge Exchange Processes (SEEP)
• JGOFS Ocean Margin Program-
• LOICZ co-sponsored by IGBP and IHDP
• IMBER- Integrated Marine Biogeochemistry and
  Ecosystem Research; IGBP
• N. American Continental Margins Group,
  U.S.Carbon Cycle Science Program
• US Climate Change Science Program, “The First
  State of the Carbon Cycle Report (SOCCR)”
• And many others…
   Modeling the coastal zone…
• 0-D boundry in box models separating land from
  sea (IPCC 4th assessment Report, no fluxes or
  inventories of C in coastal zone)
• 1-D Course-gridded open ocean models, 1D
  coastline separates land from ocean
• 2D depiction- highlights coastal zone
  (marshlands/estuaries/Shelf and even slope, but
  misses along-shelf processes (e.g. boundary
  currents, eddies, trapped waves)
• coupled 3D circulation/biogeochemical models
2-D views most common; LOICZ (Land
Ocean Interactions in the Coastal Zone)

                         After Pernetta and Milliman, 1995
IMBER-another 2D view
  Some thoughts and questions on
         coastal systems..
• Coastal margins can be C source or sink of 1Pg
  C y-1) (Hales et al., 2008)
• Coasts: 1/3 global ocean production, ½ exported
  carbon (Muller-Karger et al., 2005)
• Are coastal systems net auto- or heterotrophic?
  In mid-Atlantic bight, off-shelf export exceeds
  coastal influx. Net autotrophic and a carbon sink.
• General rule of thumb for rivers with relatively
  low sediment concentrations such as in Maine
  and Quebec…90% of carbon export from rivers
  is as DOC (Maybeck 1982; Moore et al.
  2011;Dahm et al, 1984; Opsahl et al.,1999;
  Lobbes et al., 2000; Romankevich et al., 2000)
 Monterey Time Series-Both source
(narrow band) and sink (broad band)



                       Chavez et al.; SOCCR Report
       Total N. American Corg discharge
          from rivers into estuaries…
                                                                       What are the
                                                                       error bars on
                                                                     Summarized from Meybeck,
                                                                     1982; Mulholland & Watts
                                                                     ’82; Meybeck, ’93; Ludwig
                                                                     et al., ’96; Aitkenhead &
                                                                     McDowell, ’03

Hales, Cai, Mitchell, Sabine and Schofield.; N. American Continental Margin Report; US C Cycle Science Prog
Focus on “Land-sea connections in the Gulf of
Maine” NASA-Interdisciplinary Science (Balch,
Aiken, Barnard, Huntington, Roesler, Xue)
Research Problem: Optically-active
colored dissolved organic matter (CDOM)
influenced by its terrestrial origins.
Defining spatial and temporal variability in
GoM requires understanding CDOM export
Study Area: Penobscot Watershed, River,
Bay and Gulf of Maine

                                               Objective: Estimate daily DOC flux from
                                               the Penobscot River and its tributaries,
                                               transformations in river and bay, fate in
                                               GoM, modeling of DOC & POC export
                                               and algorithm development.
      The story starts with some extreme
            precipitation events…

             Gardiner Maine: wettest year in over 100+ years


                                         pp        p    p   p

Of 8 years >1.4m y-1, half during GNATS                  GNATS
               Gardner Maine: 3rd driest year in 100+ years
This translated major years for
  DOC Export (incl. 2010)…

  ‘02   ‘03   ’04   ’05     ’06   ’07   ’08   ’09   ’10
                                        Tom Huntington, USGS
 The quality of colored dissolved organic
matter changes in a non linear fashion as it
        moves from land to sea…

         Norm FCDOM-LOBO = -0.000175*S2 – 0.02525*S+1
A.Barnard, WETLabs; G. Aiken, T. Huntington (USGS); C. Roesler (Bowdoin)
 GNATS-Gulf of Maine North Atlantic
          Time Series
• 12+ year transect time series
  across Gulf of Maine (35
  years if you include historical
  data on same line)
• Sample design uses flexible
  schedule vessels (ferries,
  small research vessels) that
  can specifically target clear-
  sky days for concurrent
  satellite and ship
2004-A dry year               MODEL of the
                              DOC Time Series
                              Oct to Dec ’04 &

                          2005-Wettest year on record

             Mg DOC L-1

Xue, Univ. Maine                    Mg DOC L-1
                      Note significant step decrease in log maximum
                                                       Pmax (mg C
                              primary production after 2007
                                                                      m-3 d-1)
Year round sampling





                           70               69         68         67                  66
                                               Longitude (deg W)
                          300                  200            100                     0
                                         Dist. from Yarmouth, NS (km)
                               WMCC         EMCC               JB                SS
                      Note step increase in log DIN after 2007…due to mixing of deeper,
                                                         NO3+NO2 (mM)
                            nutrient-rich water to surface? Decreased drawdown?
Year round sampling






                            70                69        68         67                          66
                                                Longitude (deg W)
                           300                  200            100                             0
                                          Dist. from Yarmouth, NS (km)
                                WMCC         EMCC                 JB                      SS
                      Note increase in river derived CDOM on west side of Gulf
                      (competing with primary producers for light abosrption?)
Year round sampling

                        70              69         68         67                      66
                                           Longitude (deg W)
                       300                 200            100                         0
                                     Dist. from Yarmouth, NS (km)
                           WMCC         EMCC              JB                     SS
      What is known about these
    changes? Multiple independent
   data fields showed step changes:
• Extraordinary amounts of freshwater injected into the GOM
  as reflected in salinity field
• Vertical mixing increased in upper 50m (temp profiles)
• Surface nutrients increased
• POC & PIC-specific growth rates decreased, hence
  decreased nutrient draw down
• Chlorophyll and productivity anomalies covary (i.e. both
  standing stocks and rates)
• Potential for competition for light between CDOM
  (delivered with river discharge) and chlorophyll
• Other factors? Increases in grazing? (Top-down control)
• Complex coastal systems make for enigmatic, counter-
  intuitive results
“Land-to-sea carbon export from the northeast
watersheds of North America to the northwest
Atlantic Ocean”- NASA IDS-Sept ’11: Balch (Bigelow),
      Huntington (USGS), Schaaf (UMass Boston),
Aiken(USGS), Claire(Env. Canada), Nemani(NASA Ames),
               Boulanger(Univ. Quebec)

        St. Lawrence            Gulf of Maine watershed

Watersheds emptying into the NW
    Atlantic- 1.2 million km2
Onset and decline of terrestrial productivity changes
  fast…we will track how this tracks through the
     watershed in terms of organic carbon…


MODIS true color albedo
…New England foliage                               10/15/04
                                    Crystal Schaaf, U. Mass Boston
Major advances in coastal remote
New Directions…Surface Salinity
        from Aquarius

                  Joe Salisbury, Univ. New Hampshire
The first study of land
– ocean dynamics
using space based

“Spatial and temporal coherence
between Amazon River
discharge, salinity, and light
absorption by colored organic
carbon in western tropical
Atlantic surface waters”

Salisbury et al., 2011
JGR Oceans

New opportunities with 2 new
global coverage SSS sensors:
1.ESA’s SMOS (Soil Moisture
Ocean Salinity)
  GEO-CAPE coastal observations                           Continuous view from Geo at 95W
  from a geostationary satellite…
• Discriminate physical from biological forcing
  • Rates of processes and diurnal changes
  Primary productivity, photooxidation, material transport
• Sub-mesoscale resolution (lateral scales <1km)
• Short time scale resolution of tides, wind-driven
  currents, blooms)
• Land-Ocean exchange
• More opportunities for cloud-free viewing
• Impacts of climate change and human activity
• Hazardous event monitoring at high frequency time        Tracking Gulf of Mexico Oil Spill
  scales (oil slicks, HABs, etc.)
              Societal Benefits
• Detection and tracking of hazards
• Post-storm Assessments (e.g., flood detection)
• Water Quality / Ecosystem Health
• Water clarity forecasting
• Link data to models and decision-support tools and
processes (e.g., predict hypoxic regions). Sediment
transport (navigation)
• Assessment of climate variability and change                                MODIS image
Autonomous vehicles allow higher
resolution, longer duration measurements of
coastal zone, below the depths that
satellites can see…

                       Balch; GNATS crossing June-July 2010
                                        The Impact of Climate Variability on Primary Productivity and Carbon
                                         Distributions in the Middle Atlantic Bight & Gulf of Maine (CliVEC)
    Objectives                                                 A. Mannino, M. Mulholland, K. Hyde & D. Lary   Poster 105
    • Refine and validate satellite algorithms for
    Primary Productivity (PP) model, POC, DOC,                                         in situ Surface Ocean C fixation (μmol C L-1 d-1)
    aCDOM and aph for the continental margin of                                                     overlain on MODIS SST
    northeastern U.S.
    • Examine the impacts of inter-annual and
    decadal-scale climate variability, including river
    discharge, on PP, POC and DOC.
Dissolved Organic Carbon (μmol C L-1)


                                                                                                                            Aug 2009

                                             MODIS-Aqua 2004                                                  SST (°C)
                            • Large rivers represent extremes in carbon
                              cycling and fluxes for margins; source of
                              uncertainty in continental and global carbon
GulfCarbon: Carbon            budgets
System Dynamics in the
                            • Objective- characterize the fate of terrestrial
Large River-Dominated         inputs of carbon and nutrients and their impact
Northern Gulf of Mexico       on shelf and Gulf wide carbon cycling
Coastal Margin              • Large number of cruises conducted along coastal
Steven E. Lohrenz – U. Mass   margin of northern Gulf of Mexico
Wei-Jun Cai, Wei-Jen Huang,
Yongchen Wang, Xianghui Guo,
Feizhou Chen – U. Georgia
Kevin Martin, Sumit Chakraborty,
Sarah Epps, Kjell Gundersen – U.
Southern Miss.
Other Collaborators:
Mike Murrell, John Lehrter (EPA), Bill
Miller, Tim Hollibaugh (U. Georgia),
Ron Benner, Cedric Fichot (NC
State), John Paul (USF)

                                         Conceptual representation of major plume processes and
                                         hypothetical relationships to air-sea fluxes of CO2
                        NASA Interdisciplinary Science program;
Assessing Impacts of    employs an integrated suite of models in
Climate and Land Use    conjunction with remotely sensed and in situ
Change on Terrestrial-  observations to describe processes
Ocean Fluxes of Carbon controlling fluxes on land, their coupling to
and Nutrients and Their riverine systems, and the delivery of
Cycling in Coastal      materials to estuaries and the coastal ocean
Steven E. Lohrenz – U. Mass Dartmouth
Wei-Jun Cai – U. Georgia
Hanqin Tian – Auburn
Ruoying He – North Carolina State
Charles Hopkinson – U. Georgia
Katya Fennel – Dalhousie
Stephan Howden – U. Southern Miss.
Other Collaborators:
Scott Denning (Colorado St.), Watson
Gregg (NASA), Chris Sabine (NOAA)

                                        The effects of climate change and land-use/land-cover
                                        change on TN exports to the Gulf of Mexico as estimated by
Poster 52                               the DLEM
USECoS- U.S. Eastern Continental
     Shelf Carbon Cycling
M Friedrichs, E Hofmann, B Cahill, K Fennel, K Hyde, C
Lee, A Mannino, R Najjar, S Signorini, H Tian, J Wilkin, Y
                Xiao, J Xue (Poster 23)

Use ocean
biogeochemical and
circulation models to 1)
quantify coastal carbon
2) how these fluxes
may be modified as a
result of climate and
land use change.
Synthesized data of
  North American
  coastal margins
show it to be a net
source of 19+/- 22
      Tg C y-1

Chavez, F.P., T. Takahashi, W.-J. Cai, G. Friederich, B. Hales, R. Wanninkhof, and R.A. Feely (2007)
Coastal Oceans. In: The First State of the Carbon Cycle Report (SOCCR): The North American
Carbon Budget and Implications for the Global Carbon Cycle. A Report by the U.S. Climate Change
Science Program and the Subcommittee on Global Change Research[King, A.W., L. Dilling, G.P.
Zimmerman, D.M. Fairman, R.A. Houghton, G. Marland, A.Z. Rose, and T.J. Wilbanks (eds.)].
National Oceanic and Atmospheric Administration, National Climatic Data Center, Asheville, NC, USA, pp. 157-
     The Yin and Yang of coastal
• Situated between land and the open sea, the
  continental shelves may become the refuse pits
  of developed nations and the overfished
  graveyard of underdeveloped countries J.J.
  Walsh (1988)
• We may find that the vital organs in the body of
  Gaia are not on land surfaces but in estuaries,
  wetlands and muds on the continental shelves.
  There, the rate of carbon adjusts automatically
  to regulate the concentration of oxygen and
  essential elements are returned to the
  atmosphere. James Lovelock (in Mantoura et
  al., 1991)
• Our interests in coastal processes overlap those of
  our forebears
• Our view and modeling of the coastal zone reflect
  the resolution of the measurements! In terms of
  CO2 fluxes, they can be intense sources and
  sinks, depending on time and space resolution of
• Climate change over the last century: intensifying
  hydrological cycle (via temperature/evaporation)
  and intensifying precip/river discharge in coastal
• Carbon transformations in watershed nonlinear
  with salinity-requires better resolution of
• Major changes in the coastal oceanography of the
  Gulf of Maine with record precip years (half of the
  highest rainfall years in 105 years have happened
  in last 6 years!).
• Factors responsible for productivity and nutrient
  changes in the marine end member go counter
  current paradigms
• New satellite tools will improve our ability to
  resolve carbon cycling near the coast (GEO-CAPE
  and NASA-CONEA Aquarius)
• Sophisticated new modeling techniques promise
  added insights using 3-D coupled circulation/
  biogeochemical views of the coastal zone.
                 A lot of posters to check out…
•    8: Dissolved Organic Matter as an Indicator of Changing Watersheds in Northern Rivers (George Aiken)
•    10: Possible abrupt shift in the land uptake of carbon (Beaulieu et al.)
•    11: Interannual Variability of Primary Production and Carbon Fluxes on Northeast North American Shelf: Sensitivity to Climate Change? (Cahill et
•    13: An Integrated Earth System Science Approach for Predicting Nutrient Transports from the Land to the Ocean (Yang et al.)
•    20: The effect of river freshwater discharge on the carbon cycling of the US Eastern continental shelf: Results from a three-dimensional total
     dissolved organic matter model study (Xue et al.)
•    21: Exports of Water, Carbon and Nutrients to the U.S. East Coast during 1901-2008 as simulated by DLEM: Results from a NASA IDS Project Tian
     et al.)
•    22: Model-based Analyses of Nitrogen Cycling on the Middle Atlantic Bight Continental Shelf (Tian et al.)
•    23: The U.S. Eastern Continental Shelf Carbon Cycling Project (U.S. ECoS) (Friedrichs et al.)
•    44: Land Use and Climate Alter Carbon Dynamics in Watersheds of Chesapeake Bay (Kaushal et al.)
•    52: Impacts of Climate and Land Use Change on Land-Ocean-Atmosphere Fluxes and Biogeochemical Cycling of Carbon and Nutrients in the
     Northern Gulf of Mexico Coastal Ecosystem (Steven Lohrenz et al.)
•    61: Seasonal measurements of POC,CDOM, and DOC from the Mid-Atlantic Bight, George's Bank, and the Gulf Of Maine: Modeling Carbon
     distributions from discrete data and their relationship to flow through measurements of Beam attenuation and CDOM fluorescence (Novak and
•    77: Understanding Controls on Dissolved Organic Carbon Quantity and Quality in United States Watersheds (Kevin Hanley et al.)
•    87: Characterizing the 2011 great flood plume of the Mississippi River (Subramaniam et al.)
•    105: Satellite-derived distributions of CDOM, DOC and particulate organic matter along the northeastern U.S. continental margin (Mannino et al.)
•    106: Seasonal and interannual variability in primary productivity and dinitrogen fixation along the northeastern U.S. continental margin (Margaret
     Mulholland et al.)
•     143: Forest Cover and Height in Topographically Complex Landscapes from MISR Assessed with High Quality Reference Data (Chopping et al.)
•    172: Leaching and Decomposition of Leaves from Baltimore Urban Area - Implications for Urbaniation and Gloabl Warming on carbon cycle
     (Duan and Kaushal)
•    175: Recent dynamics of arctic tundra vegetation: Field observations, remote sensing, and simulation modeling (Epstein et al.)
•    183: Measuring phytoplankton carbon: A new method for the isolation and elemental analysis of microalgae to validate satellite derived
     estimates (Jason Graff et al.)
•    216: Development of a long-term phytoplankton time series in the U.S. Northeast Continental Shelf Large Marine Ecosystem (Hyde et al.)
•    291: Diagnosis and quantification of climatic sensitivity of carbon fluxes in ensemble global ecosystem models (Wang et al.)
•    294: An Ecosystem Model Comparison on the Northeast U.S. Continental Shelf Using Data Assimilation (Xiao and Friedrichs)
•    123: Spatial scales of biogeochemical variability and image resolution for remote sensing in river plumes. (Aurin and Mannino)
•    134: CDOM optical properties in the southeastern Bering Sea during summer (D'Sa et al.)
•    162: Forecasting Future Land Use and Hydrology: A Case Study of the Upper Delaware River Watershed (Goetz et al.)

                                   Thank you very much!!

To top