T.J. Griffis
Created Aug 3, 2009
Edited Feb 17, 2011
KCMP Tall tower meta file
Minnesota tall tower trace gas observatory (TGO)

These data were originally archived and shared with researchers at Penn State (Natasha Miles, Ken Davis) 
as an additional data source for the RING2 project (see also http://www.ring2.psu.edu/). 
Please contact Tim Griffis (tgriffis@umn.edu) regarding the use and sharing of these data.

This file describes data posted in the following text files:

1. KCMP2007.txt
2. KCMP2008.txt


These files include the following variables:

1. Day of Year (local standard time, hourly values)
2. CO2 concentration measured at approx 200 m using tunable diode laser spectroscopy (micromol/mol)
3. CO2 concentration measured at approx 100 m using tunable diode laser spectroscopy (micromol/mol)
4. flag- if > 0 then mass flow controller is less than set point and isotope ratio data are lower quality
5. flag- if > 0 TDL calibration values are not within expected range and isotope ratio data are lower quality
6. flag- if > 0 CO2 values appear to be out of biophysical limits

all NaN values indicate missing data



Last file generated was July 2, 2010 
*exported the 2009 tall tower dataset for Natasha Miles.


For complete details regarding the measurement technique and site characteristics please
see:

"Influence of C4 vegetation on the 13CO2 discrimination and isoforcing in the Upper Midwest, United States",
T.J. Griffis, J.M. Baker, S.D. Sargent, M. Erickson, J. Corcoran, M. Chen, and K. Billmark 
(Global Biogeochemical Cycles, 2010, 24, GB4006, doi:10.1029/2009GB003768) (and Auxiliary Material) 


The Tall Tower Trace Gas Observatory is currently supported by the National Science Foundation, Lower Atmosphere Chemistry Section
(ATM-0546476), the Office of Science (BER) United States Department of Energy (DE-FG02-06ER64316),
and the United States Department of Agriculture - National Institute of Food and Agriculture (USDA NIFA/2010-65112-20528).
We express our sincere thanks to Minnesota Public Radio (KCMP 89.3 "The Current") and Tom Nelson for their logistical support.


Since spring 2007 measurements at the tall tower have included carbon and oxygen isotopes of CO2 based on laser spectroscopy,
and traditional eddy fluxes of energy, water, and carbon. Carbon isotope measurements were discontinued in 2010. 
Nitrous oxide concentrations have been measured near continuously since spring 2010. Water vapor isotope measurements
were initiated in spring 2010.

Carbon dioxide mixing ratio data from the Trace Gas Observatory have been used to help support the Ring 2
High-precision, high-accuracy CO2 mixing ratio measurements in support of the
North American Carbon Program Mid Continent Intensive. For more information see RING2 (http://www.ring2.psu.edu).