ORCHIDEE Development Section

Project CAMS41 Phase 2
Implementation of CH4 wetland emissions in CTESSEL model


CTESSEL plant functional types

PFT Number of pixels Area, Mkm2 CH4 flux (GCP-2019), TgC/y
PFT1 Crops, mixed farming56432 (23.63%)15.36 (12.86%)8.592 (9.47%)
PFT2 Short grass25072 (10.5%)10.56 (8.84%)3 (3.31%)
PFT3 Evergreen needleleaf22720 (9.51%)6.95 (5.82%)6.746 (7.44%)
PFT4 Deciduous needleleaf12484 (5.23%)3.09 (2.59%)0.691 (0.76%)
PFT5 Deciduous broadleaf19020 (7.96%)5.42 (4.54%)3.351 (3.69%)
PFT6 Evergreen broadleaf25516 (10.68%)14.38 (12.04%)25.358 (27.96%)
PFT7 Tall grass26996 (11.3%)9.88 (8.27%)8.024 (8.85%)
PFT9 Tundra39624 (16.59%)8.73 (7.31%)2.58 (2.84%)
PFT10 Irrigated crops10472 (4.38%)3.7 (3.09%)7.329 (8.08%)
PFT11 Semidesert32796 (13.73%)12.62 (10.57%)0.816 (0.9%)
PFT13 Bogs and marshes7436 (3.11%)1.26 (1.06%)2.447 (2.7%)
PFT16 Evergreen shrubs3704 (1.55%)0.97 (0.81%)0.136 (0.15%)
PFT17 Deciduous shrubs12924 (5.41%)3.9 (3.27%)1.925 (2.12%)
PFT18 Mixed forest - Wood10740 (4.5%)4.01 (3.36%)2.413 (2.66%)
PFT19 Interrupted forest73544 (30.79%)18.6 (15.57%)15.995 (17.6%)
not accounted 1.31 (1.44%)
Total 238 820 119.44 90.71


Wetland CH4 emission formulization

\( f_\mathsf{CH4} = s \cdot f_\mathsf{wet} \cdot \mathsf{PRSOIL\_STR} \cdot q_{10}^{\frac{\mathsf{PTSOIL(1)}}{10}}\)

CTESSEL variables used (routine SRFCOTWO)

CTESSEL respiration

\( \mathsf{PRSOIL\_STR} = \mathsf{FSN} \cdot \mathsf{FWCO2} \cdot \mathsf{RVR0VT} \cdot \mathsf{RQ}_{10}^{\frac{\mathsf{TSOIL}-25}{10}} \)

\( \mathsf{RQ}_{10} = 2.5665 - 0.05308 \cdot \mathsf{TSOIL} + 0.00238 \cdot \mathsf{TSOIL}^2 - 0.00004 \cdot \mathsf{TSOIL}^3 \)

Additional parametrization

Global Wetland Extent Fraction

The data are taken from the ORCHIDEE-WET global simulation at 1°-resolution drived by ERA5 atmospherical forcing (2010-2016) conducted by S.Peng.
The fraction of wetland area was calibrated with GIEMS (Global Inundation Extent from Multi-Satellites) and Gumbricht et al. 2017 data (doi: 10.1111/gcb.13689).
The data in CTESSEL are used as monthly climatological dataset.

CH4 emission data (used for validation)

GCP-2019 inversion products
Mean/median across 11 products
Individual GCP-2019 products

CTESSEL global run

Forcing : E2OBS
Period : 2012-2014 (first two years are considered as spinup)

First results of the global optimization


First results of the multi-site optimization:

Parameter Prior Min Max Posterior
s 1.0 0.001 100 0.13
q10 2.0 1.1 3.9 1.33

CTESSEL simulations (PALS sites)ORCHIDEE-WET global simulation (drived by ERA5 forcing)Optimization
Soil RespirationSoil TemperatureWetland FractionCH4 Emissionref / prior / post
(seasonal cycle)
ref and post only
(seasonal cycle)
Posterior CH4 flux
(s = 0.13, q10 = 1.33)
Amplero
Audubon
Blodgett
Bondv
Boreas
Brooking
Bugac
Cabauw
Castel
Degero
ElSaler
ElSaler2
Espirra
FortPeck
Goodwin
Harvard
Hesse
Howard
Howlandm
Hyytiala
Kaamanen
Kruger
Loobos
Majadas
Matra
Merbleue
MitraE
Mopane
Palang
Quebecc
Quebecf
Rocca1
Rocca2
Sodan
Sylvania
Tharandt
Tonzi
Tumba
UniMich
Vaira
Wallaby
Willow