CARBON-TESSEL

The CTESSEL model (in GEOLAND2, 2009-2012)

• A carbon module (Boussetta et al., 2012) has been added to the latest ECMWF land surface model version (Balsamo et al. 2011), in order to simulate the photosynthesis processes fixing carbon dioxide into the biomass (the so-called gross primary production, GPP) and the release of carbon dioxide via land biogenic processes (ecosystem respiration, RECO). The photosynthsis and carbon emission parameterizations were developed in collaboration with GEOLAND consortia and originated from the Ags-scheme developments (Jacobs 1994, Calvet et al. 1998, Calvet 2000, Calvet et al. 2001, Gibelin et al. 2006, Albergel et al 2010).

• This scheme has been adapted to the BATS land characterization (Dickinson et al. 1993) and added to the Hydrology-Tiled ECMWF Scheme for Surface Exchange over Land (H-TESSEL, Balsamo et al. 2009, van den Hurk et al. 2000, Viterbo and Betts 1999, Viterbo et al. 1999, Viterbo and Beljaars 1995), which benefits from quite accurate simulations of soil moisture and energy fluxes at the surface.

• CTESSEL introduces the capability of interacting to atmosperic carbon transport models as those considered in the Global Monitoring for Environment and Security - Atmospheric Services (GAS), providing the biospheric Net Ecosystem Echange (NEE) as surface boundary condition.

• An extensive verification based on a number and variety of field site experiments, gathered by the FLUXNET/CEOP/SRNWP Observing networks have been performed (see Figure and table above).

  Country	Name of the site	FLUXNET label	Vegetation Type
  Finland	Hyytiala	fi-hyy	Evergreen Needleleaf Forest
  France	Le Bray	fr-lbr	Evergreen Needleleaf Forest
  Italy	Monte Bondone	it-mbo	Interrupted Forest
  USA	Bartlett	us-bar	Mixed Forest
  Canada	Mer Bleue	ca-mer	Deciduous Broadleaf Forest
  Netherland	Loobos	nl-loo	Evergreen Needleleaf Forest
  USA	ARM-site Lamont	us-arm	Crops
  USA	Tonzi ranch	us-ton	Woody Savannas
  Italy	Roccarespampani2	it-ro2	Evergreen Shrub

  Selected FLUXNET Tower sites (from LaThuile synthesis) for CTESSEL evaluation.

Correlation of modelled and observed Net Ecosystem Exchange NEE for CTESSEL over 9 sites with different dominant biomes compared with the MACC prescribed fluxes (from Global Fire Emissions Database GFED3 Carnagie Ames Stanford Approach (CASA) model described in Van der Werf et al. 2010)

• In areas where field-sites observations are not available intercomparison with widely used NEE products are used. The key facts and limitations of the current scheme are evaluated in offline simulations driven by accurate meteorological forcing to limit the considerations to the parameterizations adopted.

Global map of the Net Ecosystem Exchange (24-hour accumulation) simulated by Integrated Forecasting System at ECMWF from the first operational stream.

• The operational Land Data Assimilation System is ingesting observations from the screen-level SYNOP stations (2m temperature and relative humidity) as described in Mahfouf (2000) and de Rosnay et al. (2011). The quality of the soil moisture operational output is verified in Albergel et al. (2011) and supports the quality of land atmosphere fluxes. A dedicated Leaf-Area-Index data assimilation is under development based on previous work by Jarlan et al (2009).

• The globally integrated land carbon dioxide Net Ecosystem Exchange obtained from offline multi-year simulations is compared with the multi-model NEE products collection available from the CarboScope portal http://www.carboscope.eu/ developed in the framework of the Integrated Carbon Observation System (ICOS).

  

CTESSEL prototype (GEOLAND-1, 2004-2007):

The CTESSEL land surface model was initially introduced at ECMWF (Lafont et al. 2006) under the framework of GEOLAND-1 EU-funded research project, and it used offline land surface simulations driven by near-surface atmospheric forcing to simulate vegetation growth and carbon cycle at the surface. Highlights from the results obtained in GEOLAND-1 are reported below.

Net Ecosystem Exchange simulated by CTESSEL (BERMS-Old Aspen site)

Global simulations (GEOLAND-1, 2004-2007):

• Leaf Area Index (LAI)
  Climatological Leaf Area Index for January (left) and July (right) simutated by CTESSEL.

• Carbon Fluxes (Net Ecosytem Exchange)
  

Monthly ecosystem NEE fluxes for the month of January (upper panels) and July (lower panels) for three models: CTESSEL, CASA, SiB.

Impact in Atmospheric-coupled simulation (GEOLAND-1 and GEMS 2004-2007):

The demo shows the evolution of 1-year land surface carbon fluxes produced by the CTESSEL scheme developed at ECMWF under the GEOLAND project. These fluxes have been tested in a coupled GCM/CTM within the framework of the European project GEMS in order to evaluate their impact on modelling the variation of atmospheric CO2 concentrations.

The animations show the daily variation of the NEE (Net Ecosystem Exchange) CO2 fluxes and the daily distribution of the atmospheric CO2 concentrations in the free troposphere (averaged between 500 and 700 hPa).

Within the European project GEMS, the capability of adding tracers in the NWP forecast model has been coded based on the existing modelling framework for advection, convection and vertical diffusion (ECMWF, 2007).

Various climatologies were used to describe CO2 fluxes at the surface. The terrestrial natural biosphere fluxes are from CTESSEL. They are annually balanced and were used at their hourly resolution to resolve the diurnal cycle of the natural biosphere. A linear interpolation was used to provide the fluxes at the model time step.
The air-sea CO2 exchange is described by a monthly mean climatology and is based on the revised version of Takahashi et al 2002. This version uses wind speeds from 10-m height instead of 0.995 sigma-level. Anthropogenic emissions are based on the EDGAR.3.0 1x1 degree global Map for 1990 (Olivier and Berdowski, 2001) rescaled to the CDIAC (Carbon Dioxide Information Analysis Centre) country level estimates for 1998.
These emissions are kept constant throughout the years. Finally, wildfire emissions are from the Global Fire emissions Database version 2 (van der Werf et al., 2006) and are provided at an 8-day time resolution using MODIS Fire hot spots (Giglio et al., 2003). These emissions have been injected at the surface given the lack of information on the fire intensity time evolution. Apart from wildfire emissions none of the prescribed CO2 surface fluxes is year specific. All data sets were interpolated to the horizontal resolution of the model. Our runs are done at a resolution of approximately 1.125x1.125 degree and 60 sigma hybrid levels (T159L60).

• GLOBAL NEE fluxes in micromolesC / m2 / s (a 1-year animation here)

Aknowledgements:

This work used eddy covariance data acquired by the FLUXNET community and that entered the LaThuile Open-Access synthesis dataset available via the web-site http://www.fluxdata.org. We gratefully acknowledge the PIs at all the sites from which data were taken for this study and the institutions and agencies that support data collection at these sites.

Links:

GEOLAND, http://www.gmes-geoland.info/

MACC, http://www.gmes-atmosphere.eu/

ICOS, http://www.icos-infrastructure.eu/

References:

Albergel, C., J.-C. Calvet, A.-L. Gibelin, S. Lafont, J.-L. Roujean, C. Berne, O. Traulle, and N. Fritz, 2010, Observed and modelled ecosystem respiration and gross primary production of a grassland in southwestern France. Biogeosciences, 7, 1657–1668.

Albergel, A., P. de Rosnay, G. Balsamo, L. Isaksen, J. Muñoz Sabater, 2011: Soil moisture analyses at ECMWF: evaluation using global ground-based in-situ observations, J. Hydrometeor. (in revision), also available as ECMWF Tech. memo 651 [pdf].

Balsamo, G., S. Boussetta, E. Dutra, A. Beljaars, P. Viterbo, B. Van den Hurk, 2011: Evolution of land surface processes in the IFS, ECMWF Newsletter, 127, 17-22.

Balsamo, G., P. Viterbo, A. Beljaars, B. van den Hurk, M. Hirschi, A.K. Betts, and K. Scipal, 2009: A Revised Hydrology for the ECMWF Model: Verification from Field Site to Terrestrial Water Storage and Impact in the Integrated Forecast System. J. Hydrometeor., 10, 623-643.

Boussetta, S., G. Balsamo, A. Beljaars, J.-C. Calvet, S. Lafont, B. van den Hurk, P. Viterbo, C. Jacobs, M. Balzarolo, 2012:Natural land carbon dioxide exchanges in the ECMWF Integrated Forecasting System (IFS): Offline validation, ECMWF Tech. Memo. (in preparation).

Boussetta, S., G. Balsamo, A. Beljaars, T. Kral, L. Jarlan, 2011: Impact of a satellite-derived Leaf Area Index monthly climatology in a global Numerical Weather Prediction model, Int. J. Remote Sensing (accepted), also available as ECMWF Tech. Memo. 640 [pdf].

Calvet J.C., Noilhan J., Roujean J.-L., Bessemoulin P., Cabelguenne M., Olioso A., Wigneron J.-P., 1998: An interactive vegetation SVAT model tested against data from six contrasting sites. Agric. For. Meteor., 92, 73-95.

Calvet, J.-C., 2000, Investigating soil and atmospheric plant water stress using physiological and micrometeorological data, Agric. For Meteorol., 103, 229-247.

Calvet J.C., and Soussana, J.F.,2001, Modelling CO2 enrichment effects using an interactive vegetation SVAT scheme. Agric. For. Meteor., 108, 129-152.

Dickinson, R.E., A. Henderson-Sellers, P.J. Kennedy and F. Giorgi, 1993. Biosphere Atmosphere Transfer Scheme (BATS) version 1e as coupled to the NCAR Community Climate Model. NCAR/TN-387+STR, 72 pp.

de Rosnay, P., M. Drusch, G. Balsamo, C. Albergel, L. Isaksen, 2011: Extended Kalman Filter soil moisture analysis in the IFS, ECMWF Newsletter, 127, 12-16.

ECMWF, 2010 IFS documentation (IFS 2010) [Land surface physics (Part IV, Chapter 7, pdf) and land data assimilation (Part II, Chapter 11, pdf)].

Gibelin, A.-L., J.-C. Calvet, J.-L. Roujean, L. Jarlan, and S. O. Los, 2006: Ability of the land surface model ISBA-A-gs to simulate leaf area index at the global scale: Comparison with satellites products, Journal of Geophysical Research, 111, D18102, doi:10.1029/2005JD006691.

Jacobs, C. M. J., 1994, Direct impact of atmospheric CO2 enrichment on regional transpiration. PhD thesis, Wageningen Agricultural University.

Jarlan, L., G. Balsamo, S. Lafont, A. Beljaars, J.C. Calvet and E. Mougin, 2008: Analysis of Leaf Area Index in the ECMWF land surface scheme and impact on latent heat and carbon fluxes: Applications to West Africa, J. Geophys. Res., 113, D24117. also available as ECMWF Tech. Memo. 544 [pdf].

Lafont S., A. Beljaars, M. Voogt, L. Jarlan, P. Viterbo, B. van den Hurk, J.-C. Calvet, 2006: Comparison of CTESSEL CO2 fluxes with TransCom CO2 fluxes. Proc. Second Recent Advances in Quantitative Remote Sensing II, Torrent (Valencia), Spain, 26-29 September 2006.

Van den Hurk, B. J. J. M., P. Viterbo, A. C. M. Beljaars, and A. K.Betts, 2000, Offline validation of the ERA40 surface scheme. ECMWF Tech. Memo 295, ECMWF, 43 pp.

Van der Werf  G. R., J. T. Randerson, L. Giglio, G. J. Collatz, M. Mu, P. S. Kasibhatla, D. C. Morton, R. S. DeFries, Y. Jin, and T. T. van Leeuwen.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997–2009)., Atmos. Chem. Phys., 10, 11707-11735, 2010.

Viterbo, P., and A.K. Betts, 1999: Impact on ECMWF forecasts of changes to the albedo of the boreal forests in the presence of snow. J. Geophys. Res., 104D, 27,803-27,810.

Viterbo, P., A.C.M. Beljaars, J.-F. Mahfouf, and J. Teixeira, 1999: The representation of soil moisture freezing and its impact on the stable boundary layer. Q. J. Roy. Meteor. Soc., 125, 2401-2426.

Viterbo, P., and A.C.M. Beljaars, 1995: An improved land surface parametrization scheme in the ECMWF model and its validation. J. Climate, 8, 2716-2748.