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gremau / NMEG_FluxProc

Code used to process and manage eddy covariance data for the New Mexico Elevation Gradient.
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Revise "ensure carbon balance" step for partitioned carbon fluxes #3

Open gremau opened 9 years ago

gremau commented 9 years ago

Should we fix or remove the "ensure carbon balance" step for partitioned carbon fluxes?

The UNM_ameriflux_filemaker_TWH script has a step in which the GPP and RE values produced by the partitioning tool are adjusted to balance the carbon budget (GPP - RE = NEE). This step:

  1. Recalculates GPP as RE (modeled) - NEE (observed).
  2. Sets negative GPP values to zero and adds these to modeled RE.
  3. Removes nighttime positive GPP values and reduces RE by the same amount?

I'm pretty sure that this results in a bias. The GPP and RE values provided by the Reichstein partitioner should already be balanced, so subtracting negative GPP and adding it to RE makes both of these fluxes bigger. I'm not sure what the effect of the nighttime removal is yet.

gremau commented 9 years ago

For now I am including GPP, RE, and NEE without this ensure carbon balance step as columns in new Ameriflux files. Fluxes that have been altered have column headers ending with _ecb or _oldecb.

We should look at how these different versions of partitioned fluxes compare.

see commit 8f11c532bb6a54ceb1b050f9c78ce394042621a6