Emerging modules for the ASM: Biogeochemistry

By Clara Deal with contributions from Scott Elliott

Outline

Introduction - Critical issues

Complex interconnectivity

Sparse observations

Emerging modules?

Example of overall system

Existing ecosystem models

Biogeochemical component models

Important features to resolve

Pan-Arctic approach

Complex interconnectivity demands consideration of an ecology of advection.

• different shelf characteristics – freshwater input

• stratification

• currents

Figure (and slide title) modified from Carmack et al. 2006

Marine biogeochemistry in the Arctic remains seriously under sampled.

A first time series for Franklin Bayhttp://www.cases.quebec-ocean.ulaval.ca/

CABANERA

There is a critical need for gridded nutrient data beyond WOA.

One Growing Family Tree: U.S. CCSM and abrupt change

Land model is NSF/DOE CLM with coupled C/N and global dynamic veg

Emerging: Boreal albedo/veg connections (DOE Impacts)Emerging: Methane from permafrost (DOE Impacts)

Ocean model is NSF/DOE POP with global eco and C/N /P/Fe/Si

Emerging: Ice algae and DMS (DOE Epscor in CICE)Emerging: High latitude specialists (DOE Epscor in CICE)Emerging: Marine clathrate CH4 release (DOE Impacts)

Regional evolution of CCSM biogeochemistry:

RACM incorporating Walsh ecodynamics in seaNo terrestrial Arctic grid in this family as yet

(slide from Scott Elliott)

A couple emerging biogeochemistry modules were mentioned yesterday during session 2. Current state of Regional Arctic Models.

• RCAO – Döscher/Jones

RCO Model – SCOBI bio-chemistry (Baltic Sea)

• ECCO2 – Heimback/Menemenlis

Lifetime, transport and fate of riverine DOC in the Arctic Ocean (Manizza et al. in press)

A few coupled physical-biological models have been applied to Arctic waters.

References Model and submodels

Dim.

Ice ecosystem

High-latitude waters

Coupled sea ice model

Shuert and Walsh 1993; Walsh et al. 1994 & 2004

ecosystem, carbonate system

3-D none Bering and Chukchi Sea

none

Wassman and Slagstad 1993; Slagstad et al. 1999

ecosystem, carbonate system

3-D, 1-D

none Greenland and Barents Sea

none

Lavoie et al. 2005 & 2009

ecosystem 1-D yes Mackenzie Shelf in the Beaufort Sea

dynamic

Jin et al. 2006, 2007 & 2009; Deal et al. 2000

ecosystem, DMS submodel

1-D yes SE Bering Sea, Chukchi Sea shelf; Gulf of AK

non-dynamic

Nishi and Tabeta 2005

ecosystem 1-D yes Lake Saroma non-dynamic

Important features to resolve:

• Horizontal transport – nutrients, biomass

• Ocean stratification

• Timing of ice retreat and algal release

• Mixing zone and euphotic layer depths

Timing of ice retreat impacts phytoplankton bloom timing and shapes the structure and function of food web.

Extreme seasonality in ice cover results in highly variable mixing zones and euphotic layer depths – in space and time.

Pan-Arctic approach

• contiguous domains

• controls – e.g. nutrients and light

• “ecology of advection”

“Food webs and physical-biological

Coupling on pan-Arctic shelves: Unifying concepts and

comprehensive perspectives”

Eddy Carmack, Paul Wassman