U.S. JGOFS SMP

U.S. JGOFS Synthesis & Modeling Project
Nicholas Bates Christopher Sabine
Assessment of temporal variability in global inorganic carbon distributions NSF OCE-9819977 / OCE-9903393 07/99-07/02
PROJECT DESCRIPTION:	The central objective of this project is to synthesize the individual U.S. JGOFS and related studies into a common perspective to generate a global picture of the current shallow water inorganic carbon distribution and variability. The first task will be to examine the seasonal component of the shallow inorganic carbon variability and evaluate the relative physical and biological controls on total carbon dioxide (TCO₂) and total alkalinity (TA) in different regions. This evaluation will involve traditional property-property analysis in conjunction with mechanistic models being developed at Princeton and Bermuda. The potential impact of ignoring this variability in mass balance estimates (e.g., anthropogenic CO₂ estimates and carbon transport calculations) will be examined along with techniques for removing seasonal biases from shallow carbon measurements. Fits of TCO₂ and TA as a function of commonly measured hydrographic parameters will provide a basis for producing gridded maps of de-seasonalized (annual mean average) surface TA and TCO₂. These maps will be very useful for initializing and evaluating global or regional models. De-seasonalized surface inorganic carbon values can not only help in model development, but are part of an important first step in isolating interannual variability in surface inorganic carbon. Evaluation of this interannual variability will help provide insights into the potential responses of the ocean to future climate change. The goals of this project directly address all three of the major program elements of the JGOFS Synthesis and Modeling Project (SMP): 1) global and regional carbon balances; 2) mechanistic controls of local carbon balances and 3) extrapolation, monitoring and prediction. The results of this project will also indirectly impact the other elements of the SMP by providing maps of seasonal carbon variability and de-seasonalized carbon distributions which can be used to evaluate seasonal and annual mean models. This work will be a collaborative effort between PIs directly involved in time-series work (Bates, Bermuda Biological Station), in the JGOFS/WOCE global CO₂ survey (Sabine, Princeton) and in global carbon modeling (Sarmiento, Princeton). In addition, close collaborations with a number of other investigators involved in both the measurement and modeling aspects of inorganic carbon have been initiated. The affiliations of the Princeton and Bermuda investigators with both the modeling and measurement communities puts this project in a key position to facilitate the close interaction between the model and measurement groups. This close interaction is necessary to synthesize the JGOFS results into a set of models used for prediction (the central goal of the SMP).
DATA:	results available from CDIAC as a GLODAP product
PUBLICATIONS:	References related to this project are listed at: http://www.bbsr.edu/Labs/co2lab/nickglob.html
RELATED PROJECTS:	Hansell; Bates; Murnane "Mass Balance assessments of carbon partitioning: A contribution to the U.S. JGOFS SMP" Sabine; Key; Feely; Millero; Wanninkhof; Kozyr "Synthesis and interpretation of the NOAA/DOE global CO2 survey data"
INVESTIGATOR INFORMATION:	Nicholas R. Bates Bermuda Biological Station for Research, Inc. 17 Biological Station Lane Ferry Reach, St. George's GE01 BERMUDA tel: (441) 297-1880 x303 fax: (441) 297-8143 nick@bbsr.edu http://www.bbsr.edu/Labs/co2lab/nick.html Christopher L. Sabine NOAA/PMEL 7600 Sandpoint Way NE Seattle, WA 98115 (206) 526-4809 (206) 526-6744 sabine@pmel.noaa.gov http://www.pmel.noaa.gov/~sabine/index.html