Conclusion générale et perspectives
Ce mémoire qui s'inscrit dans le cadre du
programme AMMA (Analyse Multidisciplinaire de la Mousson
Africaine) et du projet Ouémé-2025, vise a comprendre le
fonctionnement de l'interface surface - atmosphère. L'objectif est de
réaliser une première estimation des flux
d'énergie et de documenter les flux
d'évapotranspiration en climat soudanien.
Les interactions surface - atmosphère sont complexes.
L'analyse détaillée des processus des
différents échanges qui s'effectuent dans
la couche limite atmosphérique est indispensable a leur
compréhension. Dans cette optique, l'analyse du
bilan d'énergie a la surface est une étape
incontournable. Comprendre cette relation en zone soudanienne est
particulièrement intéressant en raison du lien étroit
observé entre condition atmosphérique et
variabilité climatique, ainsi que le rOle
important que joue l'évapotranspiration dans le bilan
hydrologique.
Ce travail constitue une première analyse du
bilan d'énergie en zone soudanienne. Notre étude a
porté sur deux stations situées dans la
Donga/Bénin une jachère herbacée (Nalohou
974484N, 160457E, 449 m) et une forêt claire (Bellefoungou
979115N, 171800E, 414 m).
L'analyse
météorologique sur une année faite
(chapitre 2) a partir des données de Nalohou montre une
saisonnalité notable des paramètres climatiques. De
cette analyse, trois périodes de quinze (15) jours
chacune ont été identifiées. Les principaux termes du
bilan d'énergie de méso-échelle ont
été évalués et leur variabilité
caractérisée sur ces différentes périodes. Le
calcul des flux turbulents de chaleur est celui qui nécessite
le plus d'attention. Le flux de chaleur a la surface du sol a été
calculé par deux méthodes la méthode des
harmoniques et la formulation empirique de la FAO.
Dans un premier temps, nous avons comparé le flux de
chaleur harmonique calculé a Nalohou en janvier oi le sol est
nu et aucune pluie n'est tombée depuis des mois, avec celui
calculé a partir de la formulation de la FAO. On a
remarqué a travers cette comparaison que le flux
de chaleur calculé a partir de la formulation de FAO sous estime le flux
de chaleur a la surface du sol quand le sol est sec et chaud de
presque 50%. La conclusion tirée de cette comparaison est
que la formulation de la FAO est mise a défaut pour les sols
chauds et secs. D'autre part, on a constaté a partir de la comparaison
des cycles journaliers de G au niveau des deux sites et sur les
trois périodes que ce paramètre est plus important a
Bellefoungou qu'a Nalohou. Le déphasage
temporel et la faible amplitude observés en Novembre a Nalohou sont
liés a la couverture du sol (litière) qui diminue et
retarde la quantité d'énergie devant
parvenir a la surface du sol. Elle joue donc le rOle d'amortisseur entre la
surface du sol et l'atmosphère.
Les flux turbulents de chaleur ont été
mesurés par eddy corrélation. L'analyse de
leur qualité a permis de vérifier la fiabilité
des ces données. Plus des 75 % des données
qualifiables sont de qualité haute c'est-a-dire
qu'elles sont utilisables pour une recherche fondamentale. Aussi,
l'analyse des tracés des cycles journaliers de H
et de LE ainsi que de leurs qualités
associées a montré que les données sont de
très bonne qualité dans la journée
lorsque l'atmosphère est instable. On a
remarqué également que la
qualité de LE est liée a celle de H. Plus
l'atmosphère est turbulente et plus l'eau arrive a s'évaporer
rapidement au sein de celle-ci. On a remarqué enfin
que, les flux d'évapotranspiration mesurés sur la
forêt de Bellefoungou étaient de mauvaise
qualité avant la construction d'un pilOnne pour supporter les
appareils. L'ancien mat téléscopique était trop
court et surtout trop instable pour permettre des mesures de
qualité bonne.
Les résultats du calcul du bilan
d'énergie (Nalohou) sur les trois périodes ont
montré une saisonnalité très marquée des
flux d'énergie. La saison sèche est
caractérisée par un taux élevé du flux de chaleur
sensible et du flux de chaleur a la surface du sol; le flux de
chaleur latente est faible pendant cette période. En saison humide, le
flux de chaleur latente est prépondérant. En Novembre oii le
rayonnement net est plus élevé que ce
qui est observé en
saison sèche et en saison humide, H et G
représentent aussi les termes majoritaires du bilan. Mais, ils demeurent
plus faibles que ceux observés en Janvier. Le flux de chaleur
latente est moyen durant cette période. La variabilité
spatiale des flux de chaleur sensible et de chaleur latente a été
montrée a travers la comparaison de ces paramètres au niveau des
deux sites en saison sèche et humide. Nous pouvons a partir de cette
première analyse du bilan d'énergie donner
une dynamique de l'évapotranspiration
réelle au pas de temps mensuel, journalier et voir même de la
demi-heure.
Les travaux réalisés dans le cadre de cette
étude nous ont permis de quantifier chacune des composantes
du bilan d'énergie sur trois périodes de 15 jours
chacune dans la Donga/Bénin. Une analyse plus
poussée reste nécessaire pour l'estimation du flux de chaleur
latente au vu des résultats qui montrent une sous estimation
systématique de ce terme. D'autre part, une
attention particulière sera portée au calcul du flux a la surface
du sol aux inter-saisons en raison de la couche de litière
laissée sur le site de mesure en Novembre.
La poursuite de cette étude sur une durée plus
longue permettra de mieux caractériser les
variabilités intra et inter saisonnières des différentes
composantes du bilan. Elle permettra également
d'acquérir une meilleure compréhension du
fonctionnement de l'interface surface - atmosphère en vue de la
documentation des flux d'évapotranspiration. Il est aussi a noter
que cette étude menée sur une période plus
longue contribuera a bien identifier les paramètres
qui influencent le bilan d'énergie en zone
soudanienne. Enfin, il s'agira également de
vérifier la fermeture du bilan de masse
hydrologique a partir des mesures de
l'évapotranspiration réelle. Une comparaison entre
l'évapotranspiration réelle et l'évapotranspiration
potentielle est envisagée afin de tester le réalisme
des paramétrisations couramment utilisées en
hydrologie et qui estiment
l'évapotranspiration réelle a partir de
l'évapotranspiration potentielle.
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To Time =
Signal (u) = u-sonic Signal (v) =
v-sonic Signal (w) = w-sonic Storage Label Alpha =
Alpha
Storage Label Beta = Beta
Storage Label Gamma = Gamma
Optional mean u = Optional mean v = Optional mean w =
Rotation
From Time =
To Time =
Signal (u) = u-sonic Signal (v) =
v-sonic Signal (w) = w-sonic Alpha = Alpha
Beta = Beta
Gamma = Gamma Do 1st Rot = x
Do 2nd Rot = x
Do 3rd Rot = x
Comments
Comment = Les variables de vent sont
Comment = dans un repére instantané fonction
Comment = du vent (v-sonic-mean = 0)
1 chn statistics
From Time =
To Time =
Signal = u-sonic
Storage Label Mean = wind-sonic-speed-mean
Storage Label Std Dev = wind-sonic-speed-std
Storage Label Skewness =
Storage Label Kurtosis =
Storage Label Maximum = wind-sonic-speed-max
Storage Label Minimum =
Comments
Comment = Calcul et Retrait du Lag
Comment = pour le Licor Openpath
Comment =
Cross Correlate
From Time =
To Time =
Signal = w-sonic
Signal which lags = q-licor
Correlation type = Covariance
Output Correlation curve = 10
Storage Label Peak Time =
time-lag-wq
Storage Label Peak Value =
Cross Correlate
From Time =
To Time =
Signal = w-sonic
Signal which lags = co2-licor
Correlation type = Covariance
Output Correlation curve = 10
Storage Label Peak Time = time-lag-wco2
Storage Label Peak Value =
Cross Correlate
From Time =
To Time =
Signal = w-sonic
Signal which lags = P-licor
Correlation type = Covariance
Output Correlation curve = 10
Storage Label Peak Time = time-lag-wp
Storage Label Peak Value =
Remove Lag From Time = To Time =
Signal = co2-licor
Min Lag (sec) = -2
Lag (sec) = time-lag-wco2
Max Lag (sec) = 2
Below Min default (sec) = 0
Above Max default (sec) = 0
Remove Lag From Time = To Time =
Signal = q-licor Min Lag (sec) =
-2
Lag (sec) = time-lag-wq
Max Lag (sec) = 2
Below Min default (sec) = 0
Above Max default (sec) = 0
Remove Lag From Time = To Time =
Signal = P-licor Min Lag (sec) = -2
Lag (sec) = time-lag-wp
Max Lag (sec) = 2
Below Min default (sec) = 0
Above Max default (sec) = 0
Comments
Comment = Calcul de la pression partielle
Comment = directement en kPa
Comment = Partial pressure From Time = To Time =
Storage Label = e-vapor-licor
Apply to =
Apply by =
Variable type = Absolute density
Measured variable = q-licor-mean
Min or QC = 0.001
Max or QC = 40
Temperature (C) = T-sonic-mean
Min or QC = Max or QC = Pressure (Kpa) = P-licor-mean
Min or QC = 0 Max or QC = 105
Molecular weight (g/mole) = 18.0
Conc conv factor = 1000
Partial pressure From Time = To Time =
Storage Label = e-vapor-meteo
Apply to =
Apply by =
Variable type = Relative humidity
Measured variable = Rh-meteo
Min or QC = Max or QC = Temperature (C) = T-meteo
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = Molecular weight
(g/mole) = 18.0
Conc conv factor = 1000
Comments
Comment = Calcul de q-meteo
Comment = en g/m3
Comment = User defined From Time = To Time =
Storage Label = q-meteo
Apply to =
Apply by =
Equation =
18*e-vapor-meteo*1000/(8.32*(273.15fT-meteo)) Variable = e-vapor-meteo
Variable = T-meteo
Comments
Comment = Application du gain
q-licor-mean/q-meteo a q-licor-mean Comment =
pour rephasage de q-licor sur q-meteo
Comment = On reste en g/m3
User defined From Time = To Time =
Storage Label =
gain-q-licor-mean
Apply to =
Apply by =
Equation =
q-meteo/q-licor-mean
Variable = q-licor-mean
Variable = q-meteo
Linear
From Time = To Time =
Signal = q-licor 1st Offset = 0
1st Gain = gain-q-licor-mean
1st Curvature = 0
2nd Offset = 0 2nd Gain = 1 2nd Curvature = 0
Comments
Comment = Correction température sonique
Comment = Schotanus et al. 1983; Manuel Csat Campbell
Scientifique Comment =
T-sonic-cor=T-sonic(1-f0.51q-licor)
User defined From Time = To Time =
Storage Label = T-sonic-cor
Apply to =
Apply by =
Equation = ((T-sonic-mean--273.15)/(1
f.32*e-vapor-meteo/P-meteo))- 273.15
Variable = P-meteo
Variable = e-vapor-meteo
Variable = T-sonic-mean
Density of moist air
From Time = To Time =
Storage Label = rho-licor
Apply to =
Apply by =
Vapour pressure (Kpa) = e-vapor-licor
Min or QC = Max or QC = Temperature (C) = T-sonic-cor
Min or QC = Max or QC = Pressure (Kpa) = P-licor-mean
Min or QC = Max or QC = Density of moist air
From Time = To Time =
Storage Label = rho-meteo
Apply to =
Apply by =
Vapour pressure (Kpa) = e-vapor-meteo
Min or QC = Max or QC = Temperature (C) = T-meteo
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = Comments
Comment = Changement d'unité de la masse
volumique de l'air humide Comment = entrée en :
Comment = sortie en :
User defined From Time = To Time =
Storage Label = rho-licor
Apply to =
Apply by =
Equation = rho-licor/1000
Variable = rho-licor
Variable =
Variable =
Variable =
Variable =
User defined From Time = To Time =
Storage Label = rho-meteo
Apply to =
Apply by =
Equation = rho-meteo/1000
Variable = rho-meteo
Variable =
Variable =
Variable =
Variable =
Comments
Comment = Calcul de rhocp
Comment = en j/g
Comment =
Sensible heat flux coefficient
From Time = To Time =
Storage Label = rhoCp-licor
Apply to =
Apply by =
Vapour pressure (Kpa) = e-vapor-licor
Min or QC = Max or QC = Temperature (C) = T-sonic-cor
Min or QC = Max or QC = Pressure (Kpa) = P-licor-mean
Min or QC = Max or QC = Alternate rhoCp = 1100
Sensible heat flux coefficient
From Time = To Time =
Storage Label = rhoCp-meteo
Apply to =
Apply by =
Vapour pressure (Kpa) = e-vapor-meteo
Min or QC = Max or QC = Temperature (C) = T-meteo
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = Alternate rhoCp = 1100
Comments
Comment = flux de chaleur sensible sonique
Comment = calcul covariance
Comment = 2 chn statistics From Time = To Time =
Signal = w-sonic Signal = T-sonic
Storage Label Covariance = wT-cov
Storage Label Correlation =
Storage Label Flux = H-sonic-tmp
Flux coefficient = rhoCp-meteo
Comments
Comment = Flux de chaleur latente
Comment = Calcul covariance
Comment = 2 chn statistics From Time = To Time =
Signal = w-sonic Signal =
q-licor Storage Label Covariance = wq-cov
Storage Label Correlation =
Storage Label Flux = E-licor-tmp
Flux coefficient =
Comments
Comment = Calcul de la chaleur latente de vaporisation de l'eau
Comment = J/g
Comment =
Latent heat of evaporation
From Time = To Time =
Storage Label = L-meteo
Apply to =
Apply by =
Temperature (C) = T-meteo
Min or QC = Max or QC = Pressure (KPa) = P-meteo
Min or QC = Max or QC = LE flux coef, L = L-cst
Latent heat of evaporation
From Time = To Time =
Storage Label = L-licor
Apply to =
Apply by =
Temperature (C) = T-sonic-cor
Min or QC = Max or QC = Pressure (KPa) = P-licor-mean
Min or QC = Max or QC = LE flux coef, L = L-cst
Comments
Comment = Calcul du flux
Comment = Comment = User defined From Time = To Time =
Storage Label = LE-licor-tmp
Apply to =
Apply by =
Equation = E-licor-tmp*L-licor
Variable = E-licor-tmp
Variable = L-licor
Comments
Comment = Flux de carbone Fco2-licor-tmp
Comment = unité mmol/m2/s
Comment = 2 chn statistics From Time = To Time =
Signal = w-sonic Signal = co2-licor
Storage Label Covariance = wco2-cov
Storage Label Correlation =
Storage Label Flux = Fco2-licor-tmp
Flux coefficient = 1
Comments
Comment = Conversion de Fco2-licor-tmp
Comment = entree mmol/m3
Comment = sortie umol/m3
User defined From Time = To Time =
Storage Label = Fco2-licor-tmp2
Apply to =
Apply by =
Equation = 1000*Fco2-licor-tmp
Variable = Fco2-licor-tmp
Comments
Comment = Calcul du flux de quantité de
mouvement Comment =
Comment =
2 chn statistics From Time = To Time =
Signal = w-sonic Signal = u-sonic
Storage Label Covariance = uw-cov
Storage Label Correlation =
Storage Label Flux = momentum-sonic
Flux coefficient = rho-meteo
Comments
Comment = u-sonic* Vitesse de frottement
Comment = Comment = U star
From Time = To Time =
Storage Label = U-star
Apply to =
Apply by =
uw covariance (m2/s2) = uw-cov
Min or QC = Max or QC = Virtual temperature
From Time = To Time =
Storage Label = T-virtual
Apply to =
Apply by =
Vapour pressure (Kpa) = e-vapor-meteo
Min or QC = Max or QC = Temperature (C) = T-meteo
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = Comments
Comment = Calcul Lo
Comment = hauteur du sonique 4,95m
Comment = hauteur végétation selon
relevé Omar Stability - Monin Obhukov
From Time = To Time =
Storage Label = stability
Apply to =
Apply by =
Measurement height (m) = hauteur-sonic
Zero plane displacement (m) = disp-height
Virtual Temperature (C) = T-virtual
Min or QC = Max or QC = H flux (W/m2) = H-sonic-tmp
Min or QC = Max or QC = H flux coef, RhoCp = rhoCp-meteo
Min or QC = Max or QC = Scaling velocity
(m/s) = U-star
Min or QC = Max or QC = Comments
Comment = Corrections spectrales
Comment =
Comment =
Frequency response
From Time =
To Time =
Storage Label = freq-corr-uw
Apply to =
Apply by =
Correction type = UW
Measurement height (m) = hauteur-sonic Zero plane
displacement (m) = disp-height Boundary layer
height (m) =
Stability Z/L = stability
Wind speed (m/s) = wind-sonic-speed-mean
Sensor 1 Flow velocity (m/s) =
wind-sonic-speed-mean Sensor 1 Sampling
frequency (Hz) = Csat-sampleFreq Sensor 1 Low
pass filter type = Recursive
Sensor 1 Low pass filter time conStant = 0.02 Sensor 1
High pass filter type = Recursive Sensor 1
High pass filter time conStant = 600 Sensor 1 path length
(m) = Csat-path
Sensor 1 Time conStant (s) = Csat-TimeConStant Sensor 1 Tube
attenuation coef =
Sensor 2 Flow velocity (m/s) =
wind-sonic-speed-mean Sensor 2 Sampling
frequency (Hz) = Csat-SampleFreq Sensor 2 Low
pass filter type = Recursive
Sensor 2 Low pass filter time conStant = 0.02 Sensor 2
High pass filter type = Recursive Sensor 2
High pass filter time conStant = 600 Sensor 2 path length
(m) = Csat-path
Sensor 2 Time conStant (s) = Csat-TimeConStant Sensor 2 Tube
attenuation coef =
path separation (m) = wT-hor-path-sep Get spectral data
type = Model
Get response function from = model
Reference tag =
Reference response condition =
Sensor 1 subsampled =
Sensor 2 subsampled =
Apply velocity distribution adjustment =
Use calculated distribution =
Velocity distribution std dev=
Stability distribution std dev=
Frequency response
From Time =
To Time =
Storage Label = freq-corr-tw
Apply to =
Apply by =
Correction type = WX
Measurement height (m) = hauteur-sonic Zero plane
displacement (m) = disp-height Boundary layer
height (m) =
Stability Z/L = stability
Wind speed (m/s) = wind-sonic-speed-mean
Sensor 1 Flow velocity (m/s) =
wind-sonic-speed-mean Sensor 1 Sampling
frequency (Hz) = Csat-SampleFreq Sensor 1 Low
pass filter type = Recursive
Sensor 1 Low pass filter time conStant = 0.02 Sensor 1
High pass filter type = Recursive Sensor 1
High pass filter time conStant = 600 Sensor 1 path length
(m) = Csat-path
Sensor 1 Time conStant (s) = Csat-TimeConStant Sensor 1 Tube
attenuation coef =
Sensor 2 Flow velocity (m/s) =
wind-sonic-speed-mean Sensor 2 Sampling
frequency (Hz) = Csat-SampleFreq Sensor 2 Low
pass filter type = Recursive
Sensor 2 Low pass filter time conStant = 0.02 Sensor 2
High pass filter type = Recursive Sensor 2
High pass filter time conStant = 600 Sensor 2 path length
(m) = Csat-path
Sensor 2 Time conStant (s) = Csat-TimeConStant Sensor 2 Tube
attenuation coef =
path separation (m) = wT-hor-path-sep Get spectral data
type = Model
Get response function from = model
Reference tag =
Reference response condition =
Sensor 1 subsampled =
Sensor 2 subsampled =
Apply velocity distribution adjustment =
Use calculated distribution =
Velocity distribution std dev=
Stability distribution std dev=
Comments
Comment = Calcul de la séparation latérale Comment
=
Comment =
User defined
From Time =
To Time =
Storage Label = lat-path-sep
Apply to =
Apply by =
Equation =
SQRT((wx-hor-path-sep*sin(Wind-sonic-Direction-ang-soniclicor))*
(wx-hor-path-sep*sin(Wind-sonic-Direction-ang-sonic-licor))-Fwxver-path-sep*wx-ver-path-sep)
Variable = wx-hor-path-sep Variable = Wind-sonic-Direction
Variable = ang-sonic-licor Variable =
wx-ver-path-sep Frequency response
From Time =
To Time =
Storage Label = freq-corr-7500
Apply to =
Apply by =
Correction type = WX
Measurement height (m) = hauteur-sonic
Zero plane displacement (m) = disp-height
Boundary layer height (m) =
Stability Z/L = stability
Wind speed (m/s) = wind-sonic-speed-mean
Sensor 1 Flow velocity (m/s) =
wind-sonic-speed-mean
Sensor 1 Sampling frequency (Hz)
= Csat-SampleFreq
Sensor 1 Low pass filter type = Recursive
Sensor 1 Low pass filter time conStant = 0.02
Sensor 1 High pass filter type =
Recursive
Sensor 1 High pass filter time conStant = 600
Sensor 1 path length (m) = Csat-path
Sensor 1 Time conStant (s) = Csat-TimeConStant
Sensor 1 Tube attenuation coef =
Sensor 2 Flow velocity (m/s) =
wind-sonic-speed-mean
Sensor 2 Sampling frequency (Hz)
= Licor7500-SampleFreq
Sensor 2 Low pass filter type = Recursive
Sensor 2 Low pass filter time conStant = 0.02
Sensor 2 High pass filter type =
Recursive
Sensor 2 High pass filter time conStant = 600
Sensor 2 path length (m) = Licor7500-path
Sensor 2 Time conStant (s) = Licor7500-TimeConStant
Sensor 2 Tube attenuation coef =
path separation (m) = lat-path-sep
Get spectral data type = Model
Get response function from = model
Reference tag =
Reference response condition =
Sensor 1 subsampled = Sensor 2 subsampled = Apply
velocity distribution adjustment =
Use calculated distribution = Velocity distribution
std dev=
Stability distribution std dev=
Mathematical operation From Time =
To Time =
Storage Label = uw-cov-fc Apply to =
Apply by =
Measured variable A = uw-cov
Operation = *
Measured variable B = freq-corr-uw
Mathematical operation From Time =
To Time =
Storage Label = U-star-fc Apply to =
Apply by =
Measured variable A = U-star
Operation = *
Measured variable B = freq-corr-uw
Mathematical operation From Time =
To Time =
Storage Label = Fco2-licor-fc Apply to =
Apply by =
Measured variable A = Fco2-licor-tmp
Operation = *
Measured variable B = freq-corr-7500
Mathematical operation From Time =
To Time =
Storage Label = H-sonic-fc Apply to =
Apply by =
Measured variable A = H-sonic-tmp
Operation = *
Measured variable B = freq-corr-tw
Mathematical operation From Time =
To Time =
Storage Label = E-licor-fc Apply to =
Apply by =
Measured variable A = E-licor-tmp
Operation = *
Measured variable B = freq-corr-7500
Mathematical operation
From Time = To Time =
Storage Label = LE-licor-fc
Apply to =
Apply by =
Measured variable A = LE-licor-tmp
Operation = *
Measured variable B = freq-corr-7500
Comments
Comment = Correction de Webb pour la vapeur d'eau Comment =
Comment = Webb correction From Time = To Time =
Storage Label = LE-licor-webb
Apply to =
Apply by =
Scalar value type = Density
(g/m3)
Scalar value = q-meteo
Min or QC = Max or QC =
Water vapour value type = partial Pressure (kpa) Water
vapour value = e-vapor-meteo
Min or QC = Max or QC = Temperature (C) = T-sonic-cor
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = H flux (W/m2) = H-sonic-fc
Min or QC = Max or QC = LE flux (W/m2) = LE-licor-fc
Min or QC = Max or QC = H flux coef, RhoCp = rhoCp-meteo
Min or QC = Max or QC = LE flux coef, L = L-licor
Min or QC = Max or QC = Scalar molecular wt. = 18
Scalar flux type = LE (W/m2)
Scalar flux coefficient = 1
Min or QC = Max or QC = Alternate water vapour pressure (kpa)
=
Alternate temperature (C) =
Alternate pressure (kpa) =
User defined From Time = To Time =
Storage Label = LE-licor-Q0
Apply to =
Apply by =
Equation = LE-licor-tmp-fLE-licor-webb
Variable = LE-licor-tmp
Variable = LE-licor-webb
Variable =
Variable =
Variable =
Comments
Comment = Correction de Webb pour le co2 Comment = entrée
en mmol/m2/s
Comment = sortie en umol/m2/s
Webb correction From Time = To Time =
Storage Label = Fco2-licor-webb
Apply to =
Apply by =
Scalar value type = Density
(mg/m3)
Scalar value = co2-licor-mean
Min or QC = Max or QC =
Water vapour value type = partial Pressure (kpa) Water
vapour value = e-vapor-meteo
Min or QC = Max or QC = Temperature (C) = T-sonic-cor
Min or QC = Max or QC = Pressure (Kpa) = P-meteo
Min or QC = Max or QC = H flux (W/m2) = H-sonic-fc
Min or QC = Max or QC = LE flux (W/m2) = LE-licor-Q0
Min or QC =
Max or QC =
From Time =
To Time =
Left Axis Value = H-sonic-Q0 Right Axis Value =
H-sonic-tmp
Left Axis Minimum = -100 Left Axis Maximum = 500
Right Axis Minimum = -100 Right Axis Maximum = 500 Match
Left/Right Axes = Plot Value
From Time =
To Time =
Left Axis Value = LE-licor-Q0 Right Axis Value =
LE-licor-tmp
Left Axis Minimum = -200 Left Axis Maximum = 800
Right Axis Minimum = -200 Right Axis Maximum = 800 Match
Left/Right Axes = Plot Value
From Time =
To Time =
Left Axis Value = Fco2-licor-Q0
Right Axis Value = Fco2-licor-tmp2
Left Axis Minimum = -20 Left Axis Maximum = 20
Right Axis Minimum = -20 Right Axis Maximum = 20 Match
Left/Right Axes = Plot Value
From Time =
To Time =
Left Axis Value = q-licor-mean Right
Axis Value = T-sonic-cor Left Axis Minimum = 0
Left Axis Maximum = 25
Axis Minimum = 10
Right Axis Maximum = 50 Match Left/Right
Axes = Plot Value
From Time =
To Time =
Left Axis Value = beta Right Axis Value =
gamma Left Axis Minimum =
Left Axis Maximum = Right Axis Minimum =
Right Axis Maximum = Match Left/Right Axes = Plot
Value
From Time =
To Time =
Left Axis Value = spike-T Right Axis Value =
spike-q Left Axis Minimum =
Left Axis Maximum = Right Axis Minimum =
Right Axis Maximum = Match Left/Right Axes =
H flux coef, RhoCp = rhoCp-meteo
Min or QC =
Max or QC =
LE flux coef, L = L-meteo
Min or QC =
Max or QC =
Scalar molecular wt. = 44
Scalar flux type = Fx (umol/m2/s)
Scalar flux coefficient = 1
Min or QC =
Max or QC =
Alternate water vapour pressure (kpa) =
Alternate temperature (C) =
Alternate pressure (kpa) =
User defined From Time =
To Time =
Storage Label = Fco2-licor-Q0
Apply to = Apply by =
Equation = Fco2-licor-tmp2-f-Fco2-licor-webb Variable
= Fco2-licor-tmp2
Variable = Fco2-licor-webb
Variable = Variable = Variable = Comments
Comment = Calcul du flux de chaleur sensible corrige
Comment =
Comment = User defined From Time =
To Time =
Storage Label = H-sonic-Q0
Apply to = Apply by =
Equation =
H-sonic-fc-(0.32*rhoCp-meteo*LE-licor-Q0*(T-sonic-mean+273.15)*
Right
(T-sonic-cor--273.15))/(216.5*P-meteo*10*L-meteo) Variable =
H-sonic-fc
Variable = rhoCp-meteo
Variable = LE-licor-Q0
Variable = T-sonic-mean
Variable = T-sonic-cor
Variable = P-meteo
Variable = L-meteo
Comments
Comment = Test de Stationarite
Comment = Critère de qualite
Comment =
Stationarity
From Time =
To Time =
Signal (A) = u-sonic
Signal (B) = w-sonic
Storage Label A StdDev Stationarity =
u-stat Storage Label B StdDev Stationarity = w-stat
Storage Label AB Covariance Stationarity = uw-stat
Segment length, minutes = 5
Linear detrend segments =
Linear detrend run =
Stationarity
From Time =
To Time =
Signal (A) = co2-licor
Signal (B) = w-sonic
Storage Label A StdDev Stationarity =
Storage Label B StdDev Stationarity =
Storage Label AB Covariance Stationarity =
co2w-stat Segment length, minutes = 5
Linear detrend segments =
Linear detrend run =
Stationarity
From Time =
To Time =
Signal (A) = q-licor
Signal (B) = w-sonic
Storage Label A StdDev Stationarity =
Storage Label B StdDev Stationarity =
Storage Label AB Covariance Stationarity =
qw-Stat Segment length, minutes = 5
Linear detrend segments =
Linear detrend run =
Stationarity
From Time =
To Time =
Signal (A) = T-sonic
Signal (B) = w-sonic
Storage Label A StdDev Stationarity =
Storage Label B StdDev Stationarity =
Storage Label AB Covariance Stationarity =
tsw-Stat Segment length, minutes = 5
Linear detrend segments =
Linear detrend run =
Plot Value
.3 Annexe 2 Description des installations
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