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bgctw / REddyProc

Processing data from micrometeorological Eddy-Covariance systems
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Example import from AmeriFlux datasets #37

Closed wcrice closed 4 years ago

wcrice commented 4 years ago

I am trying to import from the AmeriFlux datasets (US-TW3 specifically) and I'm struggling with some of the columns. For example, the US-TW3 dataset doesn't include NEE. Is it possible to add an example similar to the AmeriFlux (US-TW3) data?

Thank you!

bgctw commented 4 years ago

Could you, please, provide a link to the example. What does it mean: "doesn't include NEE"? If the column naming is different, this can be solved. If there is no NEE, what do you want REddyProc use for?

wcrice commented 4 years ago

Hi!

My dataset from AmeriFlux has these column names:

> names(tw3)
 [1] "TIMESTAMP_START" "TIMESTAMP_END"   "CO2"             "H2O"             "CH4"             "FC"              "FCH4"            "FC_SSITC_TEST"   "FCH4_SSITC_TEST" "G"              
[11] "H"               "LE"              "H_SSITC_TEST"    "LE_SSITC_TEST"   "WD"              "WS"              "USTAR"           "ZL"              "TAU"             "MO_LENGTH"      
[21] "V_SIGMA"         "W_SIGMA"         "TAU_SSITC_TEST"  "PA"              "RH"              "TA"              "VPD_PI"          "T_SONIC"         "T_SONIC_SIGMA"   "SWC_1_1_1"      
[31] "SWC_1_2_1"       "TS_1_1_1"        "TS_1_2_1"        "TS_1_3_1"        "TS_1_4_1"        "TS_1_5_1"        "NETRAD"          "PPFD_DIF"        "PPFD_IN"         "PPFD_OUT"       
[41] "SW_IN"           "SW_OUT"          "LW_IN"           "LW_OUT"          "P"               "FC_PI_F"         "RECO_PI_F"       "GPP_PI_F"        "H_PI_F"          "LE_PI_F"

Here are the variable names: https://ameriflux.lbl.gov/data/aboutdata/data-variables/ I believe NEE could be included in some datasets but it isn't in this one. How would I go about calculating that? Can I do it with REddyProc?

The example shown for this repo is:

> names(EddyData)
 [1] "Year"  "DoY"   "Hour"  "NEE"   "LE"    "H"     "Rg"    "Tair"  "Tsoil" "rH"    "VPD"   "Ustar"

I'm looking for advice on how to clean up the data from AmeriFlux (attached below) so I can get ETa values for the period of record.

Thank you! AMF_US-Tw3_BASE-BADM_5-5.zip

bgctw commented 4 years ago

REddyProc does post-processing on half-hourly time series with NEE as an input variable. I guess you are looking at the high-frequency data and need to compute NEE from the correlation of CO2 with the eddies. If this is correct, you need a tool such as EddyPro from Licor. I recommend checking back with the site PI of US-Tw3 or the Ameriflux/Fluxnet portal. They usually can provide you with the half-hourly NEE data.

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