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Issues with infrared gas analyzer pressure data stream mapping

We have identified issues with infrared gas analyzer pressure data stream mapping processed through October 28, 2019 (irrespective of data collect date). This led to differential pressure (Head Pressure) being subtracted from Box Pressure and accounted for twice when calculating Total Pressure. This problem affects the following data products and all previously processed site-months.

  • H2O concentration – turbulent (DP1.00035.001)
  • CO2 concentration – turbulent (DP1.00034.001)
  • Carbon dioxide flux (DP4.00067.001)
  • Latent heat flux (DP4.00137.001)
  • Sensible heat flux (DP4.00002.001)

All of these data products are solely available within the Bundled Data Products - Eddy Covariance (DP4.00200.001).

A fix has been implemented as of October 29th, 2019 at 2:00 p.m. MDT. All data processed after this time have the correct values. Assessment of the scientific impact of this error is in progress. Within two weeks we will update this message regarding scientific impact and reprocessing time.  Please use the data portal contact form for further inquiries; select DP4.00200.001 in the Data Product dropdown list.

Update 2019-12-19

H2O and CO2 concentration measurements were not impacted by the error. Flux data median error resulting from this issue is between 1 and 5 percent, and is proportional to site elevation. The timeline for reprocessing will be determined following discussion with the Surface-Atmosphere Exchange Technical Working Group.