| Summary: | net ecosystem exchange, ecosystem respiration, and calculated gross primary productivity within a wet sedge meadow near Thule Air Base, Greenland. Total of 21 plots. Plots consist of a collar for flux measurements 6" in diameter. Data set also includes important met data for predicting carbon flux (see also thule_met_2013.xls). LiCor 6400 with custom chamber. Data were collected every few days, weather permitting. Measurements consisted of a light measurement (net ecosystem exchange) followed by a dark measurement (ecosystem respiration) where the chamber was covered in dense shade cloth. Measurement was the change in CO2 in the chamber over a two minute period. NEE and ER were calculated from this change and adjusted for water vapor concentration in the chamber and exchange of air in the open system. GEP was calculated from NEE and ER. Convention in this data set is uptake of CO2 is a negative value, release of CO2 is a positive value. Flux values were matched to the nearest-in-time 5-min met station data. Surface temperature was measured with a thermocouple attached to the LiCor 6400. csv, comma-delimited text. Data columns are: day of year, plot number, hour, minute, second, fractional day of year, net ecosystem exchange (umol m-2 s-1), ecosystem respiration (umol m-2 s-1), gross ecosystem productivity (umol m-2 s-1), PAR from the sensor on the licor (umol m-2 s-1), temperature of the ground surface (C), incoming PAR (umol m-2 s-1), reflected PAR (umol m-2 s-1), albedo (%), air temperature (C), relative humidity (%), volumetric water content (%), saNDVI, and soil temperature (C). Data set contains all measurements, not processed for non-sensical values such as GEP >0. See thule_met_2013.xls for information on met station data, and thule_flux_plot_ndvi_2013.csv for information on NDVI.
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