A regional high-resolution carbon flux inversion of North America for 2004

Abstract. Resolving the discrepancies between NEE estimates based upon (1) ground studies and (2) atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS) and an underlying biosphere (SiB3) model, both running on an identical 40 km grid over most of North America. Current operational systems like CarbonTracker as well as many previous global inversions including the Transcom suite of inversions have utilized inversion regions formed by collapsing biome-similar grid cells into larger aggregated regions. An extreme example of this might be where corrections to NEE imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to Gross Primary Productivity (GPP) and Ecosystem Respiration (ER) is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the Parameterized Chemical Transport Model (PCTM) models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America. We perform the inversion with two independently derived boundary inflow conditions and calculate jackknife-based statistics to test the robustness of the model results. We then compare final results to estimates obtained from the CarbonTracker inversion system and at the Southern Great Plains flux site. Results are promising, showing the ability to correct carbon fluxes from the biosphere models over annual and seasonal time scales, as well as over the different GPP and ER components. Additionally, the correlation of an estimated sink of carbon in the South Central United States with regional anomalously high precipitation in an area of managed agricultural and forest lands provides interesting hypotheses for future work.

[1]  Taro Takahashi,et al.  Towards robust regional estimates of CO2 sources and sinks using atmospheric transport models , 2002, Nature.

[2]  David W. Peterson,et al.  FIRE SUPPRESSION AND ECOSYSTEM CARBON STORAGE , 2000 .

[3]  J. S. Olson,et al.  Major world ecosystem complexes ranked by carbon in live vegetation: a database , 1985 .

[4]  R. E. Kalman,et al.  A New Approach to Linear Filtering and Prediction Problems , 2002 .

[5]  A. S C O T T D E N N I N G,et al.  Simulated variations in atmospheric CO 2 over a Wisconsin forest using a coupled ecosystem – atmosphere model , 2003 .

[6]  P. Ciais,et al.  Horizontal displacement of carbon associated with agriculture and its impacts on atmospheric CO2 , 2007 .

[7]  State of the Climate National Overview May 2010 National Oceanic · and Atmospheric Administration National Climatic Data , 2012 .

[8]  D. Jacob,et al.  Summertime influence of Asian pollution in the free troposphere over North America , 2007 .

[9]  Sander Houweling,et al.  CO 2 flux history 1982–2001 inferred from atmospheric data using a global inversion of atmospheric transport , 2003 .

[10]  Gregg Marland,et al.  A 1° × 1° distribution of carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1950–1990 , 1996 .

[11]  S. Verma,et al.  Testing a model of CO2, water and energy exchange in Great Plains tallgrass prairie and wheat ecosystems , 2005 .

[12]  M. Uliasz,et al.  Seeing the forest through the trees: Recovering large‐scale carbon flux biases in the midst of small‐scale variability , 2009 .

[13]  H. Fuelberg,et al.  Meteorological conditions and anomalies during the Intercontinental Chemical Transport Experiment–North America , 2007 .

[14]  A. Scott Denning,et al.  Simulations of terrestrial carbon metabolism and atmospheric CO2 in a general circulation model: Part 1: Surface carbon fluxes , 1996 .

[15]  Philippe Bousquet,et al.  What can we learn from European continuous atmospheric CO 2 measurements to quantify regional fluxes – Part 1: Potential of the 2001 network , 2008 .

[16]  Seon Ki Park,et al.  Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications (Vol. III) , 2009 .

[17]  Glenn S. Diskin,et al.  Characteristics of the atmospheric CO2 signal as observed over the conterminous United States during INTEX-NA , 2008 .

[18]  Thomas Kaminski,et al.  On aggregation errors in atmospheric transport inversions , 2001 .

[19]  A. Dalcher,et al.  A Simple Biosphere Model (SIB) for Use within General Circulation Models , 1986 .

[20]  S. Wofsy,et al.  Factors controlling CO2 exchange on timescales from hourly to decadal at Harvard Forest , 2007 .

[21]  A. Denning,et al.  Implementation of a Boundary Layer Heat Flux Parameterization Into the Regional Atmospheric Modeling System (RAMS) and its Effects on Regional Carbon Budgets , 2007 .

[22]  A. Scott Denning,et al.  Simulated and observed fluxes of sensible and latent heat and CO2 at the WLEF‐TV tower using SiB2.5 , 2003 .

[23]  Steven Pawson,et al.  Global CO2 transport simulations using meteorological data from the NASA data assimilation system , 2004 .

[24]  P. Tans,et al.  A geostatistical approach to surface flux estimation of atmospheric trace gases , 2004 .

[25]  K. Hirsch,et al.  Direct carbon emissions from Canadian forest fires, 1959-1999 , 2001 .

[26]  Kevin R. Gurney,et al.  On error estimation in atmospheric CO2 inversions , 2002 .

[27]  Scott D. Miller,et al.  Seasonal drought stress in the Amazon: Reconciling models and observations , 2008 .

[28]  S. Pawson,et al.  Global CO 2 transport simulations using meteorological data from the NASA data assimilation system , 2004 .

[29]  R. Pielke,et al.  A comprehensive meteorological modeling system—RAMS , 1992 .

[30]  D. Randall,et al.  A Revised Land Surface Parameterization (SiB2) for Atmospheric GCMS. Part I: Model Formulation , 1996 .

[31]  Gloor,et al.  A Large Terrestrial Carbon Sink in North America Implied by Atmospheric and Oceanic Carbon Dioxide Data and Models , 2022 .

[32]  Ni Zhang,et al.  Evaluation of modeled atmospheric boundary layer depth at the WLEF tower , 2008 .

[33]  John C. Lin,et al.  Toward constraining regional‐scale fluxes of CO2 with atmospheric observations over a continent: 1. Observed spatial variability from airborne platforms , 2003 .

[34]  Philippe Bousquet,et al.  What can we learn from European continuous atmospheric CO 2 measurements to quantify regional fluxes – Part 2: Sensitivity of flux accuracy to inverse setup , 2008 .

[35]  E. Lokupitiya,et al.  Incorporation of crop phenology in Simple Biosphere Model (SiBcrop) to improve land-atmosphere carbon exchanges from croplands , 2009 .

[36]  Kevin Schaefer,et al.  Global monthly averaged CO2 fluxes recovered using a geostatistical inverse modeling approach: 2. Results including auxiliary environmental data , 2008 .

[37]  K. Davis,et al.  Observations and simulations of synoptic, regional, and local variations in atmospheric CO2 , 2007 .

[38]  G. Robertson,et al.  Greenhouse gases in intensive agriculture: contributions of individual gases to the radiative forcing of the atmosphere , 2000, Science.

[39]  J. Randerson,et al.  An atmospheric perspective on North American carbon dioxide exchange: CarbonTracker , 2007, Proceedings of the National Academy of Sciences.

[40]  Anna M. Michalak,et al.  Global monthly averaged CO2 fluxes recovered using a geostatistical inverse modeling approach: 1. Results using atmospheric measurements , 2008 .

[41]  G. A. Petersona,et al.  Reduced tillage and increasing cropping intensity in the Great Plains conserves soil C , 1998 .

[42]  G. Collatz,et al.  Coupled Photosynthesis-Stomatal Conductance Model for Leaves of C4 Plants , 1992 .

[43]  G. Katul,et al.  Soil fertility limits carbon sequestration by forest ecosystems in a CO2-enriched atmosphere , 2001, Nature.

[44]  J. Canadell,et al.  Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems , 2001, Nature.

[45]  E. Rastetter,et al.  Potential Net Primary Productivity in South America: Application of a Global Model. , 1991, Ecological applications : a publication of the Ecological Society of America.

[46]  Philippe Ciais,et al.  Weak Northern and Strong Tropical Land Carbon Uptake from Vertical Profiles of Atmospheric CO2 , 2007, Science.

[47]  Mark M. Wheeler,et al.  Verification of High-Resolution RAMS Forecasts over East-Central Florida during the 1999 and 2000 Summer Months , 2002 .

[48]  S. Freitas,et al.  THE COUPLED AEROSOL AND TRACER TRANSPORT MODEL TO THE BRAZILIAN DEVELOPMENTS ON THE REGIONAL ATMOSPHERIC MODELING SYSTEM: VALIDATION USING DIRECT AND REMOTE SENSING OBSERVATIONS , 2006 .

[49]  K. Davis,et al.  Simulated variations in atmospheric CO2 over a Wisconsin forest using a coupled ecosystem–atmosphere model , 2003 .

[50]  Philippe Bousquet,et al.  Daily CO2 flux estimates over Europe from continuous atmospheric measurements: 1, inverse methodology , 2005 .

[51]  T. Başar,et al.  A New Approach to Linear Filtering and Prediction Problems , 2001 .

[52]  A. Denning,et al.  Carbon flux bias estimation employing Maximum Likelihood Ensemble Filter (MLEF) , 2007 .

[53]  C. Justice,et al.  A Revised Land Surface Parameterization (SiB2) for Atmospheric GCMS. Part II: The Generation of Global Fields of Terrestrial Biophysical Parameters from Satellite Data , 1996 .

[54]  R. Alig,et al.  Forest Carbon Dynamics in the Pacific Northwest (USA) and the St. Petersburg Region of Russia: Comparisons and Policy Implications , 2006 .

[55]  Roger A. Pielke,et al.  Application of the Receptor Oriented Approach in Mesoscale Dispersion Modeling , 1991 .

[56]  K. Davis,et al.  A multiple-scale simulation of variations in atmospheric carbon dioxide using a coupled biosphere-atmospheric model , 2004 .