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Data Description and Documentation --

Eddy Covariance, Scintillometer, Radiation, Soil Heat Flux and Supporting Data Collected in

Support of the Idaho NSF EPSCoR Flux Team during 2010 – 20141

Wenguang Zhao and Richard G. Allen2, 2014

Site and Data Collection Support:

Idaho EPSCoR - National Science Foundation Research Infrastructure Improvement (RII) grant EPS

– 0814387;

Idaho Agricultural Experiment Station;

Idaho Engineering Experiment Station;

US Geological Survey – Landsat Science Team

Primary Team Investigators: Dr. Richard G. Allen, University of Idaho Dr. Matt Germino, Idaho State University (now USGS) Dr. V. Sridhar, Boise State University (now VPI) Dr. Wenguang Zhao, University of Idaho, Post-doc Mr. Clarence Robison, University of Idaho, Research Associate

Sites:

1. Island Park Lodgepole Pine Energy Balance Flux Site Installed October-November, 2010 Vegetation: 50 year old moderately dense, relatively uniform Lodgepole pine (pinus contorta) with thick grass/forbs understory. Clear cut in approximately 1970. Mean maximum tree height is 15 m. Average tree spacing is about 4 m with occasional clearings and meadows. Site Description: Island Park Energy Balance Flux Site: - Description and Sensor Placement by Richard G. Allen, Sept. 19, 2010, revised March 17, 2011. http://www.kimberly.uidaho.edu/epscor/ Coordinates: South Tower: 44o 28’ 20.1”, 111o 22’ 25.1” W North Tower: 44o 29’ 16.3”, 111o 22’ 29.2” W

1 A suggested citation for this document and flux data from the three sites is: Zhao, W. and R.G. Allen. 2014. Data Description

and Documentation -- Eddy Covariance, Scintillometer, Radiation, Soil Heat Flux and Supporting Data Collected in Support of the Idaho NSF EPSCoR Flux Team during 2010 – 2014. University of Idaho, Kimberly, ID, 17 p. Available at: http://www.kimberly.uidaho.edu/epscor/ 2 Document compiled by R.Allen, Univ. Idaho, October 2014. Emails are: wzhao@uidaho.edu and rallen@uidaho.edu

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2. Hollister Sagebrush Energy Balance Flux Site Installed Fall 2009 Vegetation: Moderately dense Big Sagebrush (Artemisia tridentata), approx. 0.5 to 1.0 m tall Site Description: Hollister Sagebrush site Documentation of Soil Sensor Locations following Installation November 24-25, 2009 by R.Allen, 11/30/2009, revised October, 2011 http://www.kimberly.uidaho.edu/epscor/ Coordinates: LAS Receiver: 42o 18’ 54.0” N, 114o 41’ 52.8” W LAS Transmitter: 42° 19' 54.1"N, 114° 42' 2.09"W Eddy Covariance site no. 1: 42° 19' 26.56"N, 114° 42' 3.29"W Eddy Covariance site no. 2: 42° 19' 8.64"N, 114° 42' 3.46"W 3. Raft River Cheatgrass Energy Balance Flux Site Installed Fall 2009 Vegetation: Mostly Invasive Cheatgrass (Bromus tectorum) with some drilled crested wheat grass and invasive wild mustard Site Description: Raft River Cheat Grass site – Installed 2009 – 2010 Documentation of Sensor Locations, October and November, 2009 by R.Allen, 11/30/2009, revised October, 2011 http://www.kimberly.uidaho.edu/epscor/ BLS 900 LAS Transmitter: 42º 34’ 43.8”N, 113º 23’ 53.5”W BLS 900 LAS Receiver: 42º 34’ 31.7”N, 113º 24’ 26.8”W Eddy Covariance Site no. 1: 42º 34’ 43.0”N, 113º 24’ 03.4”W Eddy Covariance Site no. 2: 42º 34’ 32.2”N, 113º 24’ 20.7”W

Experimental Objectives To better understand how sagebrush-steppe, cheatgrass-steppe and lodgepole pine

forest/understory consume and meter consumption of water and how they partition environmental energy under current and future climate conditions

To improve satellite - based remote sensing of evapotranspiration (ET) and surface energy balance models

To improve hydrologic process (snow melt) and weather forecasting models (such as WRF - Noah)

Equipment All three sites have the following equipment:

One Scintec BLS900 large aperture scintillometer

Two or three 3-D sonic anenometers (RMYoung 81000 or CSI CSAT3)

One or two LiCor 7500 Infrared Gas Analyzers (for H2O and CO2 fluxes)

Two or more 4-component Net Radiometers

One or more pyranometers

Ten to twenty four REBS HFT-3.1 soil heat flux plates at two depths and in five or more locations (subsites)

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One or two Hukseflux HFP01SC Self-Calibrating Soil Heat Flux Plates

30 or more thermocouples in the soil

Ten to twenty eight Decagon Echo5 soil water content sensors

One or more Decagon MPS - 1 Soil water potential sensors

Six to twenty nine Campbell Scientific CS616 volumetric soil water content sensors

One or more Vaisalla relative humidity and air temperature sensors

Two or more tipping bucket precipitation gauges with antifreeze-filled catches to melt snow

3-m profile (at Raft River and Hollister) or 24-m profile (at Island Park) consisting of five to seven 0.003 inch diameter fine-wire thermocouples

One Apogee SI-111 and one Apogee SI-121 infrared sensor

Instrument Testing, Intercomparison and Calibration All three sites have as much duplication and redundancy in instrumentation as possible. This is done to support assessment of measurement integrity and instrument calibration and performance. Prior to deployment of the Scintec BLS900 scintollometers, a rigorous intercomparison was made among the three units in 2009. Results are summarized in a Poster pdf at the Kimberly web site: http://www.kimberly.uidaho.edu/epscor/ One unit was found to require factory recalibration. RMY 3D sonic anemometers were intercompared and several were found to need factory recalibration due to apparent damage during shipment that altered the flight paths between transducers. RMY testing included operating in a closed room, where the sonic temperature measurement should be close to that of ambient air temperature. Net radiation (Rn) instruments were intercompared prior to deployment. A number of Hukseflux NR01 sensors were found to require factory rebuilds to correct for a filter malfunction on the long-wave sensors. The intercomparison included NR01 and Kipp and Zonen CNR1 four-component radiometers and several REBS Q7 net radiometers. In 2012, a K&Z four-component radiometer with CG4 and CM21 sensors was factory calibrated and intercompared with several NR01 sensors with good results. Some details are provided in a Poster pdf at the Kimberly web site: http://www.kimberly.uidaho.edu/epscor/

General Data Processing

Eddy Covariance (temperature, velocity, water vapor and CO2 data) were collected as time series at 20 Hz for the first year and then at 10 Hz later on to reduce power consumption. The time series were reduced to 30 minute period flux averages after collection using corrections within an Excel spreadsheet setting. Corrections included time lag adjustments among instruments, data spike removal, flagging for air flow direction from the backside of the CSAT3 anemometer, influence of slope (stream flow coordinate rotation), and WPL corrections. No energy balance closure adjustment has been applied to the H and LE data.

BLS900 data were collected at 5 Hz at Raft River and Hollister and at 5 Hz during spring – fall at Island Park and at 1 Hz during winter to reduce power consumption. Data were processed to 5 minute averages for Cn2 (structure function constant of refractive index fluctuation for wavelength of scintillometer) and 30 minute averages for fluxes in real-time.

Radiation, soil heat flux and soil temperature sensors were scanned at 10 second intervals and averaged over 5 minute and 30 minute intervals.

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Volumetric soil water content and soil water potential were scanned at 10 minute intervals and averaged over 30 minute intervals

Soil heat flux at the surface is calculated by adding the plate reading to the change in heat storage above the plate. Change in heat storage is usually calculated using four or more TC readings that are fitted to a 3rd degree polynomial equation to extrapolate temperature to the surface. The Hollister site includes a 0.4 m deep pit (to caliche) instrumented with 8 thermocouples for a complete soil heat flux estimation independent of soil heat flux plates (http://www.kimberly.uidaho.edu/epscor/Hollister/ThermocouplePlacementSoilProfileatHollister.ppt).

Data Access and Citation

These data have been collected with primary support by the Idaho NSF EPSCoR Research Infrastructure Improvement (RII) grant EPS – 0814387 and by Idaho Agricultural Experiment Station; Idaho Engineering Experiment Station; and US Geological Survey – Landsat Science Team. The data are distributed freely, upon request, according to the Idaho EPSCoR Research Data RII Policy3 which states that “All derived data products built from external data sources will cite the external data sources and collectors in the metadata for the new derived product.” These data can be cited by reference to this containing publication. A suggested citation for the data is: Zhao, W. and R.G. Allen. 2014. Data Description and Documentation -- Eddy Covariance, Scintillometer, Radiation, Soil Heat Flux and Supporting Data Collected in Support of the Idaho NSF EPSCoR Flux Team during 2010 – 2014. University of Idaho, Kimberly, ID, 17 p. Available at: http://www.kimberly.uidaho.edu/epscor/

Data Quality Flags The following data quality flags have been assigned to eddy covariance, radiation, soil heat flux and related data. The assignments are based on line by line analysis of data values and ranges of values. The data quality flags are included in the data distribution spreadsheets.

Flags 0 -- Good data 1 -- Deviates from the same type of data that is obtained from a different instrument 2 -- Bad wind direction (from the rear of the CSAT3 sonic anemometer 3-based eddy covariance H and LE fluxes data only)

4 -- Rain event

8 -- Data are out of normal range

16 -- No data, not a number, or divided by 0

32 -- Battery voltage is too low and the data are not reliable When more than one type of event occurs, the data quality flags are added together. For example, a

data quality flag of 6 means both a bad wind direction and rain event occur during the same period.

Spreadsheet Data Storage

3 http://www.kimberly.uidaho.edu/epscor/files/ID_EPSCoR_Data_Policies_V5_Final.pdf

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30-minute data, following QAQC and processing, have been archived in Excel spreadsheets, with one

spreadsheet file per month. An example name for these spreadsheets is:

Island_Park_monthly_data_and_flag_output8_2013-05.xlsm where “Island Park” is the location, May

2013 is the month for the data, and ‘8’ is a version number for the spreadsheet template. Each

spreadsheet generally contains 18 sheets containing the following information:

Parameters – location, SHF plate depths, thermocouple depths, soil characteristics, soil heat storage calculations, documentation of heat storage calculation using a polynomial equation; any radiation correction factors, scintollometer parameters;

BLS_900 – 30 minute Scintec BLS900 results for Cn2, CT

2 and sensible heat flux, H. BLS_flags -- Flags from the above table for the BLS data RMY – 30 minute data for CO2, LE and H fluxes for the RMY sonic anemometer, if present and

supporting turbulence and air flow parameters; estimated CO2 concentration and sonic temperature, air density, estimated air pressure, wind speed and wind direction. Also included are specific humidity and air temperature from the Vaisalla RH sensor.

RMY_flags – Flags as defined in the above table for all parameters computed CSAT– 30 minute data for CO2, LE and H fluxes for the CSAT3 sonic anemometer, if present and

supporting turbulence and air flow parameters; estimated CO2 concentration and sonic temperature, air density, estimated air pressure, wind speed and wind direction. Also included are specific humidity and air temperature from the Vaisalla RH sensor. If two RMY’s are present, like in Raft River, then this sheet may be named as Eddy1 and Eddy2.

CSAT_flags – Flags as defined in the above table for all parameters computed Towers – Various sensor measurements recorded by dataloggers located on the ‘towers’ at Island Park.

These include battery voltage, Vaissala RH and T, measurements from all pyranometers and net radiometers mounted on the tower (or tripod at RR and Hollister), snow depth, IRT temperature, soil water content of sensors connected to the tower (generally beneath the tower poles), precipitation, and snow depth for both the South Tower and for the North Tower

Tower_flags – Flags as defined in the above table for all parameters computed N_Soil – Data collected at the North Tower of Island Park (IP) via the 3 m tripod and associated

datalogger, including battery voltage, panel temperature, AM16 panel temperature, Vaisalla RH and T, and ground-based pyranometers and net radiometers (below canopy); soil heat flux plates, soil temperature, soil water content, and total soil heat flux at the ground surface

N_Soil_flags – Flags as defined in the above table for all parameters computed S_Soil– Data collected at the South Tower of Island Park (IP) via the 3 m tripod and associated

datalogger, including battery voltage, panel temperature, AM16 panel temperature, Vaisalla RH and T, and ground-based pyranometers and net radiometers (below canopy); soil heat flux plates, soil temperature, soil water content, and total soil heat flux at the ground surface

S_Soil_flags – Flags as defined in the above table for all parameters computed G1_Fig – Figures showing 48-hour long traces of soil heat flux for the South Tower site at the surface

(top figure), measured by the plates (middle figure) and storage change (bottom figure) for all soil heat flux sites. These figures are colorized to show the same color for the two SHF plates that are buried at the same subsite. “Back” and “Ahead” buttons are tied to Visual Basic macros to advance the graphics to another day’s data for quick and ready viewing.

G2_Fig – Figures showing 48-hour long traces of soil heat flux for the North Tower site at the surface (top figure), measured by the plates (middle figure) and storage change (bottom figure) for all soil heat flux sites. These figures are colorized to show the same color for the two SHF plates

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that are buried at the same subsite. “Back” and “Ahead” buttons are tied to Visual Basic macros to advance the graphics to another day’s data for quick and ready viewing.

Rad_Fig – Similar to G1 and G2_Figures, this sheet contains 48-hour graphics for incoming and reflected short wave radiation (top), and net radiation (bottom) figure, with ‘Back’ and ‘Ahead’ buttons for all sensors combined into a single graph for intercomparison.

H_ET_Fig -- Similar to G1 and G2_Figures, this sheet contains 48-hour graphics for sensible heat flux and latent heat fluxes derived from the eddy covariance systems and from the BLS900 scintillometer system. Generally, H from three systems and LE from two systems is shown, with ‘Back’ and ‘Ahead’ buttons.

Wind_Fig -- Similar to G1 and G2_Figures, this sheet contains 48-hour graphics for wind speed and wind direction measured by the two eddy covariance systems, with ‘Back’ and ‘Ahead’ buttons to advance the graphs.

Recommended Instrumentation

Soil Heat Flux. The combination of soil heat flux estimates at Hollister and Raft River is generally based on a regression-based weighting of each SHF subsite determined by an energy balance closure analysis. This weighting gives preference to some subsites that are more representative of the EC footprint in terms of vegetation density, type and soil structure. Details for Hollister are given in Greth, J. MS thesis, Univ. Idaho (paper in preparation) and in a pdf poster at the Kimberly web site. A straight average of all G provides a reasonably good approximation of total G at both Hollister and Raft River. Determinations are still being made at Island Park. Net Radiation. Selection of the best Rn’s to blend for total Rn may vary with month, depending on sensor performance and cleanliness and data availability/flags. This can be determined by viewing the Rn graphs. Generally, all four-component Rn sensors that are above the canopy provide similar Rn measurements, indicating that all or nearly all can often be averaged to provide a site-representative estimate of net radiation. Sensible Heat Flux and Latent Heat Flux. The H and LE measurements should be viewed graphically to determine whether individual measurements are behaving properly. QAQC flags provide additional information or explanation of outlying data. No energy balance closure has been applied to the H and LE data. Field Logs. Field sites are visited approximately each six weeks for data retrieval and sensor cleaning

and inspection. During visits, radiation sensors are cleaned and leveled, and any adjustments or

dirtiness are noted. 3D sonic anemometer transducers and LiCor 7500 windows are inspected and

cleaned as needed. Photographs are often taken. BLS900 alignments are checked and adjusted as

needed.

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Sample photos for Island Park

Scintech BLS900 large aperture scintillometer at the Island Park south tower.

CSAT3 and LiCor 7500 eddy covariance system at the Island Park south tower.

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Soil thermocouple cable during installation at the Island Park north tower.

South tower at Island Park.

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South Tower Looking North towards North Tower

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Sample photos for Hollister

Scintillometer transmitter

A CSAT3 (left) and RMY (right) 3D

anemometer with LiCor 7500 (center) in

between for EC data redundancy,

integrity enhancement, and evaluation of

impact of sensor separation.

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Soil heat flux pit

during installation

showing placement of

two soil heat flux

plates (yellow circles),

thermocouples (blue

cables), ECHO5 water

content and ECHO

MPS1 potential

sensor (black).

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Sample photos for Raft River

Cheat grass during spring at EC site 1, Raft River.

EC site 1 during winter showing

cables to soil heat flux subsites (blue

tubes)

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Site Maps

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Raft River EPSCoR Eddy Covariance Site 1

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Raft River EPSCoR Eddy Covariance Site 2.

Participants in Instrument and Site Installations

Island Park - 2010: Richard Allen (UI), Wenguang Zhao (UI), Clarence Robison (UI), V. Sridhar (BSU), Matt

Germino (ISU), Carlos Kelly (UI), Ricardo Trezza (UI), Jeremy Greth (ISU/UI), Kevin Nuss (BSU), Xin Jin

(BSU), Jeremy Hegman (UI), Jeppe Kjaersgaard (UI), Eric Kra (UI), David Hoekema (BSU), Ramesh Dhungel

(UI), Keith Reinhardt (ISU)

Hollister - 2009: Richard Allen (UI), Wenguang Zhao (UI), Clarence Robison (UI), Jeppe Kjaersgaard (UI),

V. Sridhar (BSU), Matt Germino (ISU), Ricardo Trezza (UI), Aureo de Oliveira (UI), Jeremy Greth (ISU/UI),

Michael de Jung (UI), Jeremy Hegman (UI), David Hoekema (BSU), Sumathy Sinnathamby (BSU), Thilini

Jaksa (BSU), Muluken Muche (BSU)

Raft River - 2009: Matt Germino (ISU), Richard Allen (UI), Wenguang Zhao (UI), Jeppe Kjaersgaard (UI),

Clarence Robison (UI), Ricardo Trezza (UI), Aureo de Oliveira (UI), Jeremy Greth (ISU/UI), Angelo Teton

(ISU/ShoBan), Jeff Morgan (ISU), Niles Hasselquist (ISU), Brandy Janzen (ISU), Sara Kaiser (ISU)