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LBA-ECO CD-04 CO2 Profiles, km 83 Tower Site, Tapajos National Forest
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Revision date: October 21, 2009

Summary:

Atmospheric carbon dioxide profiles were measured at 12 levels up to 64 m at the km 83 logged tower site in Tapajos National Forest, Santarem, Para, Brazil. Data were collected over 3.5 years between June 2000-March 2004. An infra-red gas analyzer sequentially measured the concentration of CO2 at 12 heights (0.1, 0.35, 0.7, 1.4, 3, 6, 10.7, 20, 35, 40, 50, 64 m above the ground) on the tower every 48 minutes. The data, reported on a 30 minute interval, are provided in one single comma separated file.

tower


Km 83 logged tower site in Tapajos National Forest

Data Citation:

Cite this data set as follows:

Miller, S., M. Goulden, and H.R. da Rocha, 2009. LBA-ECO CD-04 CO2 Profiles, km 83 Tower Site, Tapajos National Forest. Data set. Available on-line [http://daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/947

Implementation of the LBA Data and Publication Policy by Data Users:

The LBA Data and Publication Policy [http://daac.ornl.gov/LBA/lba_data_policy.html] is in effect for a period of five (5) years from the date of archiving and should be followed by data users who have obtained LBA data sets from the ORNL DAAC. Users who download LBA data in the five years after data have been archived must contact the investigators who collected the data, per provisions 6 and 7 in the Policy.

This data set was archived in October of 2009. Users who download the data between October 2009 and September 2014 must comply with the LBA Data and Publication Policy.

Data users should use the Investigator contact information in this document to communicate with the data provider. Alternatively, the LBA Web Site [http://lba.inpa.gov.br/lba/] in Brazil will have current contact information.

Data users should use the Data Set Citation and other applicable references provided in this document to acknowledge use of the data.

Table of Contents:

1. Data Set Overview:

Project: LBA (Large-Scale Biosphere-Atmosphere Experiment in the Amazon)

Activity: LBA-ECO

LBA Science Component: Carbon Dynamics

Team ID: CD-04 (Goulden / Rocha)

The investigators were Goulden, Prof. Michael L.; Miller, Dr. Scott Dennis and Rocha, Prof. Humberto Ribeiro da . You may contact Miller, Dr. Scott D. (smiller@albany.edu)

LBA Data Set Inventory ID: CD04_CO2_Profiles

Atmospheric carbon dioxide concentrations measured at 12 levels between 10 cm and 64 m at the logged tower site in Tapajos National Forest (km 83). Data were collected over 3.5 years between June 2000-March 2004.

Related Data Set:

2. Data Characteristics:

Data were all collected within the Tapajos National Forest, 83 km south of the city of Santarem, Para. Data are presented in one ASCII file: CD04_km83_CO2_profiles.csv

There are 19 columns, representing measured or calculated quantities, separated by commas. There are 64992 records (rows), each corresponding to a 30 minute interval for a total 1354 days beginning June 29, 2000 and ending March 11, 2004. The first timestamp is experiment day 181, or June 29, 2000. The last timestamp is day 1535, or March 11, 2004, the day that a tree fell on the tower. The data are not gap-filled.

Data Quality Note: Please note that the data file has a few additional records-before and after the stated timestamps. Users may exclude records as appropriate for their analyses.

CD04_km83_CO2_profiles.csv:


File Contents / Variable Descriptions:

Column # Heading Units/format Description
1 exp_day   experiment day (0 = January 1, 2000, 00:00 hours)
2yearyyyy year
3 month mm month
4 day dd day
5 hour hh hour at start of sampling period (GMT:24 hour clock)
6 minute mm minute at start of sampling period (GMT)
7CO2_10cm ppm atmospheric CO2 concentration at 10 cm height
8CO2_35cm ppm atmospheric CO2 concentration at 35 cm height
9 CO2_70cm ppm atmospheric CO2 concentration at 70 cm height
10CO2_1_4m ppm atmospheric CO2 concentration at 1.4 m height
11 CO2_3m ppm atmospheric CO2 concentration at 3 m height
12 CO2_6m ppm atmospheric CO2 concentration at 6 m height
13 CO2_10_7m ppm atmospheric CO2 concentration at 10.7 m height
14 CO2_20m ppm atmospheric CO2 concentration at 20 m height
15 CO2_35mppm atmospheric CO2 concentration at 35 m height
16 CO2_40m ppm atmospheric CO2 concentration at 40 m height
17 CO2_50m ppm atmospheric CO2 concentration at 50 m height
18 CO2_64m ppm atmospheric CO2 concentration at 64 m height
19 fstor_64m micromoles/m2/s CO2 storage flux below 64 m

This data set is not gap-filled.

Missing data are represented by -999


Example Data Record:

exp_day,year,month,day,hour,minute,CO2_10cm,CO2_35cm,CO2_70cm,CO2_1_4m,CO2_3m,CO2_6m,CO2_10_7m,
CO2_20m,CO2_35m,CO2_40m,CO2_50m,CO2_64m,fstor_64m

174,2000,6,22,0,0,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999
174.020833,2000,6,22,0,30,486.88,474.91,475.56,472.37,467.14,463.9,462.86,428.48,410.14,401.06,399.01,399.01,12.46
174.041667,2000,6,22,1,0,494.69,489.22,483.65,474.13,472.1,470.84,466.25,469.44,410.11,403.76,399.81,397.55,3.54
...
1536.958333,2004,3,15,23,0,475.15,452.91,467.6,456.81,457.44,442.58,445.46,444.64,422.7,404.33,399.93,399.93,-999
1536.979167,2004,3,15,23,30,476.02,476.02,470.48,467.1,455.29,454.46,463.61,461.19,423.23,396.67,403.29,-999,-999
1537,2004,3,16,0,0,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,-999,0

 

Site (Region) Westernmost Longitude Easternmost Longitude Northernmost Latitude Southernmost Latitude Geodetic Datum
Para Western (Santarem) - km 83 Logged Forest Tower (Para Western (Santarem)) -54.96889-54.96889-3.01806-3.01806World Geodetic System, 1984 (WGS-84)

Time period:

Platform/Sensor/Parameters measured include:

3. Data Application and Derivation:

The amount of CO2 stored beneath the CO2 measurement inlets (64 m) can be calculated by integrating the CO2 profile between 0 and 64 m. The storage flux was then calculated by differentiating this quantity with respect to time.

Analysis of eddy covariance observations provides information useful for identifying which physiological and physical processes play dominant roles in controlling CO2 exchange. In turn, this information contributes to the development and improvement of models of ecosystem-atmosphere CO2 exchange and to understanding which processes are particularly sensitive to future change.

4. Quality Assessment:

This data set is not gap-filled. Missing values or data that were flagged as unreliable either by an objective algorithm or subjective inspection have been given a value of -999. Please note that gap-filled CO2 storage flux data are available in the related data set Miller et al. (2009).


5. Data Acquisition Materials and Methods:

An infra-red gas analyzer (IRGA, LI-COR LI7000 or, before Dec. 2000, a LI800, Lincoln NE) sequentially measured the densities of CO2 and H2O at 12 altitudes (0.1, 0.35, 0.7, 1.4, 3, 6, 10.7, 20, 35, 40, 50, 64 m above the ground) every 48 minutes. Four slpm (standard liters per minute) of air was drawn through a 2 micron filter at each altitude, down 5.5-mm inner-diameter polyethylene lined tubing (Furon Dekabon 1300), through a solenoid manifold in an enclosure at the base of the tower (Parker General Valve, Fairfield NJ), into the equipment hut, and through the IRGA cell. The average CO2 and H2O mixing rations at each level were calculated during the last minute of each 4-minute sampling interval, and observations were then interpolated to each half-hour to synchronize with the eddy flux measurements.

The pressure in the IRGA cell was actively controlled at 83 kPa (MKS Instruments, Andover MA). The IRGA was calibrated for CO2 and water vapor daily by sequentially sampling purge air, CO2 standard in air (+/-1% Scott Marin, Riverside CA), CO2 free air (Scott Marin, Riverside CA), and 16 degree C dew point air (LI-COR LI610, Lincoln NE).

6. Data Access:

These data are available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Data Archive Center:

Contact for Data Center Access Information:

E-mail: uso@daac.ornl.gov
Telephone: +1 (865) 241-3952

7. References:

None cited.

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