NASA/TMm2000-209891, Vol. 243

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Sara K. Conrad, Editors

Volume 243

BOREAS TGB-10 Volatile Organic

Carbon Data over the SSA

Hal Westberg and Brad Hall, Washington State University, Pullman

Andrea V. Jackson, Lancaster University, UK

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

November 2000

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NASA/TMm2000-209891, Vol. 243

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Sara K. Conrad, Editors

Volume 243

BOREAS TGB-10 Volatile Organic

Carbon Data over the SSA

Hal Westberg and Brad Hall, Washington State University, Pullman

Andrea V. Jackson, Lancaster University, UK

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

November 2000
NASA Center for AeroSpace Information

7121 Standard Drive

Hanover, MD 21076-1320

Price Code: A17

Available from:

National Technical Information Service

5285 Port Royal Road

Springfield, VA 22161

Price Code: A10
BOREAS TGB-10 Volatile Organic Carbon Data over the SSA

Hal Westberg, Brad Hall, Andrea V. Jackson

Summary

The BOREAS TGB-10 team collected several trace gas data sets in its efforts to determine the role of

biogenic hydrocarbon emissions with respect to boreal forest carbon cycles. This data set contains

measured VOC concentrations. These data were obtained at the SSA-OJP site from May to September

1994. The data are stored in tabular ASCII files.

Table of Contents

1) Data Set Overview

2) Investigator(s)

3) Theory of Measurements

4) Equipment

5) Data Acquisition Methods

6) Observations

7) Data Description

8) Data Organization

9) Data Manipulations

10) Errors

11) Notes

12) Application of the Data Set

13) Future Modifications and Plans

14) Software

15) Data Access

16) Output Products and Availability

17) References

18) Glossary of Terms

19) List of Acronyms

20) Document Information

1. Data Set Overview

1.1 Data Set Identification

BOREAS TGB-10 Volatile Organic Carbon Data over the SSA

1.2 Data Set Introduction

The BOReal Ecosystem-Atmosphere Study (BOREAS) Trace Gas Biogeochemistry (TGB)-10

team collected Volatile Organic Carbon (VOC) concentration data at the Southern Study Area (SSA)

Old Jack Pine (OJP) site during the growing season of 1994. The equipment used included Teflon

bags, 6-liter passivated stainless steel canisters, and a gas chromatograph. A combination of branch

enclosures and gradient and Relaxed Eddy Accumulation (REA) methods were used to make the

needed measurements.

1.3 Objective/Purpose

Emission/deposition rates of biogenic hydrocarbons (or VOC) were measured along with ambient

concentrations of biogenic hydrocarbons. We will use these data to examine (a) the role of biogenic

hydrocarbon emissions with respect to carbon cycles in the boreal forest, (b) the chemical fate of

boreal biogenic emissions, (c) the hypothesis that biospheric VOC emissions contribute to peroxide

formation, and (d) the deposition rates of hydrogen peroxide and organic peroxides.

Page 1
1.4 Summary of Parameters

Investigations of biogenic hydrocarbon emissions and tropospheric concentrations of hydrogen

peroxide and organic hydroperoxides in a boreal forest.

1.5 Discussion

None given.

1.6 Related Data Sets

BOREAS TGB-08 Monoterpene Concentration Data over the SSA

BOREAS TGB-08 Starch Data over the SSA

BOREAS TGB-08 Photosynthesis Data over the SSA

BOREAS TGB-09 Above Canopy Non-Methane Hydrocarbon Data over the SSA

2. Investigator(s)

2.1 Investigator(s) Name and Title

Dr. Hal Westberg

Washington State University

Dr. Nick Hewitt

Lancaster University

2.2 Title of Investigation

Measurement of Biogenic Hydrocarbon Fluxes

2.3 Contact Information

Contact 1: Biogenic Hydrocarbon Emissions:

Dr. Hal Westberg

Dept. of Civil and Environmental Engineering

Washington State University

Pullman, WA 99164-2710

(509) 335-1529

(509) 335-7632 (fax)

westberg@mail.wsu.edu

Contact 2: Deposition of Hydrogen Peroxide:

Brad Hall

(Dr. Candis Claiborn)

Dept. of Civil and Environmental Engineering

Washington State University

Pullman, WA 99164-2710

(509) 335-5553

(509) 335-7632 (fax)

bhall@lar.ce.wsu.edu

claiborn@wsu.edu

Page 2
Contact 3: Hydrogen Peroxide and Hydroperoxides:

Andrea V. Jackson

(Dr. Nick Hewitt)

Environmental Science Division

Institute of Environmental and Biological Sciences

Lancaster University

Lancaster LA1 4QY

United Kingdom

(44-1524)-843854 (fax)

andrea@lec.leeds.ac.uk

n.hewitt@ lancaster, ac.uk

Contact 4:

Jeffrey A. Newcomer

Raytheon ITSS

Code 923

NASA GSFC

Greenbelt, MD 20771

(301) 286-7858

(301) 286-0239 (fax)

Jeffrey.Newcomer@ gsfc.nasa.gov

3. Theory of Measurements

Three different methods were employed to measure biogenic VOC fluxes in the BOREAS SSA. A

branch enclosure technique provided individual branch-level emission estimates. Tower-based gradient

and REA methods yielded canopy-scale biogenic hydrocarbon fluxes.

Enclosure Method:

Hydrocarbon emission rates were determined using a dynamic enclosure technique. The emission

rate was calculated from the following expression:

E : C*Q/B (g C/g/s)

where C (g C/m3) (g C (g C/m3) (g C is grams carbon) is the concentration of a specific hydrocarbon,

Q (mUs) is the flow rate of air through the chamber, and B (g) is the dry leaf (needle) biomass of the

enclosed branch.

Gradient Method:

Canopy-scale biogenic hydrocarbon fluxes and hydrogen peroxide deposition velocities were

determined by the flux-gradient technique, in which the flux is expressed as the product of an eddy

exchange coefficient and the concentration gradient. The biogenic VOC flux (F) can be derived from

the eddy exchange coefficient and the measured gradient.

F = K*(dC/dz) (g C/m2/s)

where K (m2/s) is an eddy diffusion coefficient and concentration is measured in gC/m3.

The deposition velocity (Vd) of hydrogen peroxide is found from the eddy exchange coefficient and

the normalized gradient.

Page 3
Vd = K*(dC/dz)/C (m/s)

where concentration is measured in ppbV.

REA Method:

Canopy-scale fluxes of biogenic hydrocarbons were determined by the REA method at the Old

Black Spruce (OBS) site. These measurements were carried out in cooperation with Dr. Elizabeth

Pattey (BOREAS Tower Flux (TF)-07 team). In this method, air is sampled at a constant rate and

partitioned into one of two containers, contingent upon whether the vertical velocity component was

positive (upward) or negative (downward). The flux is computed from the following expression:

F = b*sw*(C2 - C1) (g C/m2/s)(g C/m2/s)

where b (dimensionless) is a weak function of stability (determined by eddy correlation measurements

of heat, water vapor, or CO2 flux), sw (m/s) is the standard deviation of vertical wind speed, and C2

and C1 (g c/m3) are the concentrations in the "upward" and "downward" containers, respectively. For

a more complete description of the REA method, one should consult the TF-07 documentation.

Hydrogen Peroxide Measurements (TGB-10b):

Hydrogen peroxide (BOREAS TGB-10b) was measured by the continuous, enzyme-catalyzed,

fluorometric method (Lazrus et al., 1986). An incoming air stream (2 L/min) was split equally into two

parts. Each gas stream was passed through a glass stripping coil in which peroxides were dissolved

into a buffer solution at pH 5.8 (0.5 mL/min, 0.004 M potassium hydrogen phthalate). To each liquid

stream (A and B), horseradish peroxidase (8,000 units/L, type II, Sigma Chemical), 0.004 M

p-hydroxyphenylacedic acid (POPHA), 0.004 M ethylenediamine tetraacetic acid (EDTA), and 0.0005

M formaldehyde (HCHO) solutions were added. Prior to the addition of the peroxidase and POPHA,

bovine-liver catalase, which destroys hydrogen peroxide, was added to stream B. The catalase

concentration is adjusted until approximately 90% of the H202 in channel B is destroyed. In both

channels, peroxidase catalyzes the reaction of peroxides with POPHA to form a fluorescent dimer with

excitation and emission wavelengths of 320 and 400 nm, respectively. The resulting signals, generated

by photomultiplier tubes, are proportional to the peroxide concentration in each photo cell. Hydrogen

peroxide concentration is the difference in signal between channels A and B.

Air was sampled at each height through a 4-meter section of 1/4" PFA Teflon tubing connected to a

PFA Teflon-coated 2-way valve (Furon). From there, the air was drawn through 40 m of PFA Teflon

line to the analytical system, located inside the instrument hut. At this point, the air stream was

separated into two streams by a PFA Teflon tee. One stream was sent to the hydrogen peroxide

instrument and the other to the ozone analyzer. The valve was switched at 18-minute intervals,

sequentially sampling air at both levels.

Hydrogen Peroxide and Organic Hydroperoxide Measurements (TGB-10e):

Ambient hydrogen peroxide and organic hydroperoxides concentrations were determined by high

performance liquid chromatography (HPLC) with fluorometric detection. The detection method is

similar to that described in the previous section. Air was drawn at 4 L/min from the inlet (24 m height)

on the TF tower through 1/4" TFE Teflon tubing to the tower base, where a gas-phase scrubber was

used to scrub peroxides from the air stream. Samples were collected in 5 mL deionlzed water. HPLC

analysis was performed immediately after sample collection.

HPLC separation was achieved on an Absorbosphere MF Plus C 18 column (Altech) with an eluent

of 0.001 M sulfuric acid with 0.0001 M EDTA delivered by a Merck-Hitachi L-6200 Intelligent HPLC

pump at a flow rate of 0.6 mL/min. After separation, the peroxides were derivatized by addition of

0.026 M p-hydroxyphenylacetic acid with 10,000 units/L of horseradish peroxidase (type II Sigmal

Chemical) in 0.5 M potassium hydrogen phthalate buffer at pH 5.8. The reaction of the fluorescence

reagent with the separated hydroperoxides takes place in a Teflon coil to ensure adequate mixing.

Following this, the pH of the resulting solution is raised to above 10 to convert the dimer to its

fluorescent anionic form using a membrane reactor constructed of Nafion (DuPont) tubing immersed in

Page 4
30% ammonium hydroxide solution. Fluorescence measurements were made using a Merck-Hitachi

spectrophotometer with excitation and emission wavelengths of 310 and 405 nm, respectively. The

HPLC analytical system was located in the instrument hut.

Formaldehyde Monitoring:

The reaction of formaldehyde with dinitrophenylhydrazine (DNPH) was the basis for the

measurement procedure used during this study. A DNPH/silica cartridge was connected to the inlet end

of a 1/4" stainless steel tube extending to 3 m above the ground. The sample flow (1 L/rain) was

generated with a small pump and monitored with a Matheson flow meter. A calibrated Tylan digital

totalizer was used to record the total volume sampled. The cartridges were exposed to the ambient air

for nominal durations of 2, 4, or 6 hours. Cartridges were brought back to Washington State

University (WSU) for analysis.

Sample and blank cartridges were eluted with 3 mL acetonitrile. Hydrazone concentrations in the

eluent were determined by reverse-phase HPLC. The HPLC analysis was performed using a LKB

modular system consisting of two pumps (LKB #2150), a 190-600 nm ultraviolet/visible wavelength

detector (LKB #2151) operated at 360 nm, and an LC gradient controller (LKB # 2152). A

Brownlee-Rainin 10-cm OD-MPS column (or comparable) with a hydrophobic, nonpolar stationary

phase (bonded on 5-micrometer spheres), preceded by a similar guard column was used for peak

separation. A gradient elution, beginning with a 50:50 water:acetonitrile ratio was used, changing to a

30:70 water:acetonitrile ratio over a period of 21 minutes. The column flow rate was 0.5 mL/min and

the sample loop volume was 20 microliters.

4. Equipment

4.1 Sensor/Instrument Description

Biogenie VOCs:

Biogenic VOC samples were analyzed on a Hewlett Packard HP5890 gas chromatograph fitted

with a cryogenic accessory and two flame ionization detectors. A freeze-out trap was used with a

six-port gas sampling valve for preconcentrating the sample prior to injection. A 30-m DB- 1 fused

silica column was used in a temperature-programmed mode (-50 deg C to 150 deg C at 4 deg/min) to

separate VOCs in the C5 to C10 range. Compound identities were determined through retention time

comparisons and mass spectral analysis. Sample volume was measured with a vacuum system

employing an evacuated vessel of known volume and a digital vacuum gauge (Validyne). Sample

volumes range from 100 to 1,000 cm3 depending upon the expected VOC concentration.

Gradient samples for biogenic VOCs were collected in 6-liter passivated stainless steel canisters.

The sample containers were cleaned prior to field deployment by heating under reduced pressure, and

then flushed with humidified, hydrocarbon-free air at room temperature. REA samples were collected

in Teflon bags. Immediately after filling, the contents of the bag were transferred to a stainless steel

canister for transport to the analytical laboratory.

Hydrogen Peroxide:

Hydrogen peroxide (TGB-10b) was measured by the dual-channel, enzyme-catalyzed,

fluorometric method. The instrument was constructed at WSU, following the procedure outlined by

K&K Instruments; Boulder, Colorado (Lazrus et al., 1986).

Ozone:

Ozone was measured with a Dasibi 1003-AH ozone sensor.

4.1.1 Collection Environment

Tower-based measurements were conducted under ambient atmospheric conditions.

Enclosure-based biogenic VOC measurements were conducted under near-ambient conditions, but at

slightly elevated temperatures.

Page 5
4.1.2 Source/Platform

All biogenic VOC, peroxide, and ozone measurements were made from ground- or tower-mounted

instruments.

4.1.3 Source/Platform Mission Objectives

The objective of these experiments was to obtain canopy-scale fluxes of biogenic VOCs and

peroxides, and branch-scale fluxes of biogenic VOCs in a boreal environment.

4.1.4 Key Variables

Emissions and/or ambient concentrations of the following trace gases were measured:

• isoprene

• alpha-pinene

• beta-pinene

• limonene

• monoterpenes

• hydrogen peroxide

• methylhydroperoxide

• hydroxymethlyhydroperoxide

• ozone

4.1.5 Principles of Operation

See Section 3.

4.1.6 Sensor/Instrument Measurement Geometry

Enclosure Sampling:

The instruments used for enclosure sampling were mounted on a battery-powered portable cart.

The bag enclosure was mounted on a tripod base, allowing access to branches 1-3 meters from the

ground.

Biogenic VOC Analysis:

The gas chromatographic system was housed in the WSU mobile lab, located at the Torch Camp

site (Highway 120, near the Torch River). This central location served to minimize the storage time for

VOC samples.

Gradient Sampling:

Inlets were located on beams protruding 1 m off the west sides of the TF towers. With winds

predominately from the south, west, or north, the samples usually contained unperturbed air. The inlet

heights (above the forest floor) are summarized below.

Old Aspen (OA) 27.5 m and 37.5 m

OBS 12.4 m and 23.3 m

OJP 16.5 m and 23.8 m Intensive Field Campaign

OJP 17.2 m and 23.8 m IFC-3

IFC)-I, IFC-2

The lower inlet at the OJP site was raised prior to IFC-3 to alleviate possible influences of the

roughness sublayer.

4.1.7 Manufacturer of Sensor/Instrument

HP5890 gas chromatograph:

Hewlett Packard

15815 SE 37th St.

Bellevue, WA 98006

Page 6
Dasibi1003-AHozoneanalyzer:

DasibiEnvironmental

616E. ColoradoSt.

Glendale,CA 91205

HP-3396Aintegrator:

HewlettPackard

15815SE37thSt.

Bellevue,WA 98006

Thehydrogenperoxidesystemwascustom-builtatWSU:

WSU TechnicalServices

WashingtonStateUniversity

Pullman,WA 99164-2801

HPLC system(TGB-10c):

Merck Ltd.

Merck House

Poole,Dorset

BH15 1TD,England

Datahandlingsystems:

Labtech

400ResearchDr.

Wilmington,MA 01887

VG DataSystems

St. GeorgesCourt

HanoverBusinessPark

Altrincham,Cheshire

WA14 5UGEngland

4.2 Calibration

4.2.1 Specifications

Hydrogen Peroxide:

The H202 gradient measurements were occasionally subject to bias. It was extremely difficult to

maintain clean sampling conditions at all times. Inlet filters cannot be used due to the potential for

severe H202 loss on filter surfaces.

Periods of unacceptable bias were encountered during the first IFC when the jack pine trees were

pollinating, and occasionally during IFC-2 and IFC-3 when bugs would collect in the sample lines.

The sample lines were sequentially flushed with methanol, water, and dry air periodically to remove

dirt, pollen, and bugs.

Ozone:

Calibration of the gas chromatograph was achieved by measuring instrument response to a known

concentration of 2,2-dimethylbutane in air (Scott Environmental Technology; cylinder # A-11). The

resulting calibration curves have been compared to a propane standard that is traceable to the National

Institute for Standards and Technology (NIST, formerly NBS) (3.08 ppm propane; ID# M3281665).

Daily span checks were performed during each field campaign using the 0.204 ppm

2,2-dimethylbutane standard.

Page 7
Formaldehyde:

High-purity formaldehyde-hydrazone was prepared by conventional methods for use as a master

standard. The master standard was diluted to concentrations of 0.2, 0.5, 1.0, 2.0, and 5.0 ppm to

establish calibration curves.

Sensors for the peripheral environmental measurements were calibrated at WSU prior to the field

sampling program. Mass flow meters were tested against a precision wet-test meter at several flow

rates. The thermocouples and amplifiers were calibrated against a NIST traceable mercury thermometer

by measuring the response with all sensors immersed in a stirred ice-water bath slowly warmed to

approximately 45 deg C. The humidity sensor was compared to calculated values for air passed

through a temperature-controlled water bath. All of the sensor calibrations were performed using the

PC laptop data system employed in the field.

4.2.1.1 Tolerance

None given.

4.2.2 Frequency of Calibration

Calibrations were performed before and after each IFC. Bias checks for peroxide gradients were

performed every few days during IFC-2 and IFC-3. No bias checks were performed during IFC-1.

4.2.3 Other Calibration Information

Hydrogen peroxide (TGB-10b):

The continuous hydroperoxide system was calibrated twice daily with liquid standards of hydrogen

peroxide in deionized water. The standards were prepared at the 10-8 M level by serial dilution of a

30% H202 reagent (Fisher). The concentration of the primary reagent was determined by titration

against KMnO4, which was then titrated against a NIST traceable sodium oxalate solution.

Line losses through the PFA Teflon tubing were measured before and after each IFC. A gas-phase

H202 generation system was used to produce a sample stream with near-ambient levels of H202. Line

losses were determined by sampling this stream with and without the tower sampling line. A critical

aspect of the peroxide gradient system is the potential for bias introduced in the two separate inlet

sections. Care was taken to ensure that bias introduced by the valve and 4-m inlet sections was

well-known and correctable. Relative bias was determined every few days by placing both inlets at the

same height and sampling ambient air for several hours. Subsequent gradients were corrected for bias,

which ranged from - 1 to 9%. When the bias surpassed 7%, samples were rejected and the valve and

sample lines were cleaned with methanol, deionized water, and peroxide-free air. After cleaning, bias

was reduced to a nondetectable level.

Hydroperoxides (TGB-10e):

Peak identities were confirmed by comparison with retention times of authentic standards.

Quantification was based on system response to hydrogen peroxide, as the same fluorescent dimer is

formed for all hydroperoxides. Calibration was carried out twice daily and was found to be linear over

the range 8x10 8 M to 5x10 6 M. The limit of detection has been determined to be less than 50 pptv.

Ozone:

The Dasibi ozone monitor was calibrated against a Dasibi ozone source/monitor model 1008-PC

(serial #3226).

Page 8
5. Data Acquisition Methods

Enclosure Method

The enclosure consisted of a cylindrical 30-liter Teflon film bag supported externally supported on

a metal frame. Hydrocarbon-free zero air (from a compressed gas cylinder) was swept through the

Teflon bag at a controlled rate. The zero air "sweep gas" was introduced through a perforated annular

ring at one end and exhausted through a port at the other end. The sweep gas was humidified by

bubbling through a water bath, maintained at ambient temperature. Carbon dioxide was added to yield

near-ambient CO2 concentrations (360 +/- 10 ppm) in the sweep gas.

Gradient Method

Ambient concentrations of biogenic hydrocarbons were measured at two heights (see Section

4.1.6) above the OBS, OA, and OJP forests. Hydrogen peroxide was measured at two heights above

the OJP forest. For biogenic hydrocarbons, 30-minute average concentrations were determined by

simultaneously filling two stainless steel canisters. Each canister was connected to a PTFE Teflon line

running from a location on the tower (above the canopy) to the tower base. For hydrogen peroxide, the

concentration at each height was measured sequentially at 18-minute intervals. The average

concentrations observed during each interval were used to compute the concentration gradient. Eddy

exchange coefficients for heat and water vapor were determined by simultaneously measuring the

fluxes (by eddy correlation) and the gradients of heat and water vapor. The respective TF groups will

provide these data.

REA Method

Canopy-scale fluxes of biogenic hydrocarbons were determined by the REA method at the OBS

site. In this method, air is sampled at a constant rate and partitioned into one of two containers,

contingent upon whether the vertical velocity component was positive (upward) or negative

(downward).

Signals from the hydrogen peroxide and ozone instruments (TGB-10b) were stored as 1-minute

averages via PC computer. Data acquisition software from Labtech was used to record signals

(voltages).

The gas chromatograph was interfaced to a pair of HP-3396A integrators for peak integration. Raw

signals were also stored via PC computer for data reprocessing.

The HPLC system for hydroperoxides was interfaced with a VG Data Systems Minichrom data

acquisition system for chromatography. The connection of the HPLC to the data system was achieved

using a chromatography server.

6. Observations

6.1 Data Notes

Hydrogen peroxide:

Periods of unacceptable bias were encountered during the first IFC, when the jack pine trees were

pollinating, and occasionally during IFC-2 and IFC-3 when bugs would collect in the sample lines.

Ozone:

Some problems with the electronic zero were detected during IFC- 1. An offset of -6 ppb relative to

the data acquisition system was discovered. This offset was easily measured on a daily basis, and

remained essentially unchanged throughout the experiment.

Page 9
6.2 Field Notes

TGB-10bPeroxidedataweredeemedquestionable(QC= 2) orunacceptable(QC= 3)duringthe

following periods:

C

IF

IF

IF

IF

IF

IF

IF

IF

*** QUALITY CONTROL (based local TIME and DOY)

(DOY EQ. 145) QC = 2

(DOY EQ i

(DOY EQ 1

(DOY EQ 1

(DOY EQ 1

(DOY EQ 1

(DOY EQ 1

(TIME .GT.

46) QC = 2

47) QC = 2

55) QC = 3

56) QC = 3

57) QC : 2

60) THEN

17. QC = 2

ENDIF

IF (DOY .EQ

IF ((TIME

ENDIF

IF (DOY .EQ

IF ((TIME

ENDIF

IF (DOY .EQ.

206)

GT. 8

212)

GT. 3

poor calibration

poor calibration

poor calibration

extreme pollen event

poor calibration

moderate pollen event

bias unknown

THEN

0) .AND. (TIME .LT. 12.0)) QC = 2 poor calibration

THEN

0) .AND. (TIME .LT. 9.0)) QC = 3

216) QC = 2

high noise level

None Given.

7. Data Description

7.1 Spatial Characteristics

7.1.1 Spatial Coverage

Biogenic VOC fluxes were determined at three tower sites in the SSA (OA, OBS, and OJP).

Peroxide and ozone concentrations were measured only at the OJP site. The North American Datum of

1983 (NAD83) coordinates for the sites are:

SSA-OA 53.62889N, I06.197779W

SSA-OBS 53.91634N, I04.69203W

SSA-OJP 53.98717N, I05.11779W

7.1.2 Spatial Coverage Map

Not available.

7.1.3 Spatial Resolution

These data represent point source measurements at the given locations.

7.1.4 Projection

Not applicable.

7.1.5 Grid Description

Not applicable.

7.2 Temporal Characteristics

Page 10
7.2.1 Temporal Coverage

Biogenic VOC samples were collected for 30-minute periods. Sampling was usually performed

from sunrise to sunset, to capture the diurnal variability. Some overnight sampling was performed at

the OA site during IFC-3. Ambient biogenic VOC and oxidation products were measured at the Torch

Camp (near Candle Lake, Saskatchewan) during each IFC. These measurements were meant to

supplement those obtained at the tower sites.

Peroxide and ozone concentrations were measured continuously during daylight hours. In

addition, many overnight sampling periods were obtained.

7.2.2 Temporal Coverage Map

Not available.

7.2.3 Temporal Resolution

No regular intervals of data collection resulted at the sites; however, data were collected on several

days during the growing season of 1994 at each location.

7.3 Data Characteristics

7.3.1 Parameter/Variable

The parameters contained in the data files on the CD-ROM are:

Column Name

SITE NAME

SUB SITE

DATE OBS

TIME OBS

ISOPRENE CONC

ALPHA-PINENE CONC

BETA-PINENE CONC

CAMPHENE CONC

CRTFCN CODE

REVISION DATE

7.3.2 Variable Description/Definition

The descriptions of the parameters contained in the data files on the CD-ROM are:

Column Name Description

SITE NAME The identifier assigned to the site by BOREAS, in

the format SSS-TTT-CCCCC, where SSS identifies the

portion of the study area: NSA, SSA, REG, TRN, and

TTT identifies the cover type for the site, 999 if

unknown, and CCCCC is the identifier for site,

exactly what it means will vary with site type.

SUB SITE The identifier assigned to the sub-site by BOREAS,

in the format GGGGG-IIIII, where GGGGG is the

group associated with the sub-site instrument,

e.g. HYD06 or STAFF, and IIIII is the identifier

for sub-site, often this will refer to an

instrument.

DATE OBS The date on which the data were collected.

TIME OBS The Greenwich Mean Time (GMT) when the data were

collected.

Page 11
ISOPRENE CONC

ALPHA-PINENE CONC

BETA-PINENE CONC

CAMPHENE CONC

CRTFCN CODE

REVISION DATE

The ambient concentration of isoprene

The ambient concentration of alpha-pinene.

The ambient concentration of beta-pinene.

The ambient concentration of camphene.

The BOREAS certification level of the data.

Examples are CPI (Checked by PI), CGR (Certified

by Group), PRE (Preliminary), and CPI-??? (CPI but

questionable).

The most recent date when the information in the

referenced data base table record was revised.

7.3.3 Unit of Measurement

The measurement units for the parameters contained in the data files on the CD-ROM are:

Column Name Units

SITE NAME

SUB SITE

DATE OBS

TIME OBS

ISOPRENE CONC

ALPHA-PINENE CONC

BETA-PINENE CONC

CAMPHENE CONC

CRTFCN CODE

REVISION DATE

[none]

[none]

[DD-MON-YY]

[HHMM GMT]

[parts per billion Carbon]

[parts per billion Carbon]

[parts per billion Carbon]

[parts per billion Carbon]

[none]

[DD-MON-YY]

7.3.4 Data Source

The sources of the parameter values contained in the data files on the CD-ROM are:

Column Name Data Source

SITE NAME

SUB SITE

DATE OBS

TIME OBS

ISOPRENE CONC

ALPHA-PINENE CONC

BETA-PINENE CONC

CAMPHENE CONC

CRTFCN CODE

REVISION DATE

Not applicable

Not applicable

Investigator

Investigator]

Gas Chromatograph

Gas Chromatograph

Gas Chromatograph

Gas Chromatograph

Not applicable

Not applicable

7.3.5 Data Range

The following table gives information about the parameter values found in the data files on the

CD-ROM.

Minimum Maximum Missng Unrel Below Data

Data Data Data Data Detect Not

Column Name Value Value Value Value Limit Cllctd

SITE NAME SSA-9OA-FLXTR SSA-OJP-FLXTR None None None None

SUB SITE TGBI0-HCR01 TGBI0-HCR01 None None None None

DATE OBS 31-MAY-94 09-SEP-94 None None None None

TIME OBS 0 2340 None None None None

ISOPRENE CONC .13 36.23 -9999 None None None

Page 12
ALPHA-PINENE CONC

BETA-PINENE CONC

CAHPHENE CONC

CRTFCN CODE

REVISION DATE

.049 5.86 -9999 None None Blank

.072 3.65 -9999 None None Blank

.055 2.88 -9999 None None Blank

CPI CPI None None None None

06-OCT-95 06-OCT-95 None None None None

Minimum Data Value --

Maximum Data Value --

Missng Data Value --

Unrel Data Value --

Below Detect Limit --

Data Not Cllctd --

The minimum value found in the column.

The maximum value found in the column.

The value that indicates missing data. This is used to

indicate that an attempt was made to determine the

parameter value, but the attempt was unsuccessful.

The value that indicates unreliable data. This is used

to indicate an attempt was made to determine the

parameter value, but the value was deemed to be

unreliable by the analysis personnel.

The value that indicates parameter values below the

instruments detection limits. This is used to

indicate that an attempt was made to determine the

parameter value, but the analysis personnel determined

that the parameter value was below the detection

limit of the instrumentation.

This value indicates that no attempt was made to

determine the parameter value. This usually

indicates that BORIS combined several similar but

not identical data sets into the same data base table

but this particular science team did not

measure that parameter.

Blank

N/A

None

-- Indicates that blank spaces are used to denote that type of value.

-- Indicates that the value is not applicable to the respective column.

-- Indicates that no values of that sort were found in the column.

7.4 Sample Data Record

The following are wrapped versions of data record from a sample data file on the CD-ROM.

SITE NAME,SUB SITE,DATE OBS,TIME OBS,ISOPRENE CONC,ALPHA-PINENE CONC,

BETArPINEN CONC,CAMPHENE CONC,CRTFCN CODE,REVYSION DATE

'SSA-9OA-FLXTR', 'TGB10-HCR01',ll-JUN-94,1500,4.41 .... 'CPI',06-OCT-95

'SSA-9OA-FLXTR', 'TGB10-HCR01',ll-JUN-94,1700,5.46 .... 'CPI',06-OCT-95

'SSA-9OA-FLXTR', 'TGB10-HCR01',ll-JUN-94,1800,6.71 .... 'CPI',06-OCT-95

'SSA-9OA-FLXTR', 'TGB10-HCR01',ll-JUN-94,1900,3.69 .... 'CPI',06-OCT-95

8. Data Organization

8.1 Data Granularity

The smallest unit of data tracked by BORIS was the data measured on a particular day at a

particular site.

8.2 Data Format(s)

The Compact Disk-Read-Only Memory (CD-ROM) files contain American Standard Code for

Information Interchange (ASCII) numerical and character fields of varying length separated by

commas. The character fields are enclosed with single apostrophe marks. There are no spaces between

the fields.

Page 13
Eachdatafile ontheCD-ROMhasfourheaderlinesof Hyper-TextMarkupLanguage(HTML)

codeatthetop.Whenviewedwith aWebbrowser,thiscodedisplaysheaderinformation(dataset

title, location,date,acknowledgments, etc.)andaseriesof HTML links to associatedatafilesand

relateddatasets.Line 5of eachdatafile is alist of thecolumnnames,andline 6 andfollowinglines

containtheactualdata.

9. Data Manipulations

9.1 Formulae

The peroxide gradient was computed from 3 successive measurements of peroxide concentration at

two levels (10-18 minutes at each level).

Peroxide_gradient = (C2 - 0.5*(Cl+C3))/delta Z

where: C 1 = concentration measured at lower level (period t)

C2 = concentration measured at upper level (period t+ 1)

C3 = concentration measured at lower level (period t+2)

Special note: If the standard error associated with C1, C2, or C3 was greater than 0.05%,the peroxide

gradient was deemed unacceptable. This procedure was performed in order to screen periods of highly

variable concentration, which might suggest unsteady-state conditions (gusts or large eddies) which

are not conducive to K-theory.

9.1.1 Derivation Techniques and Algorithms

None given.

9.2 Data Processing Sequence

9.2.1 Processing Steps

BORIS staff processed the data by:

• Reviewing the initial data files and loading them online for BOREAS team access.

• Designing relational data base tables to inventory and store the data.

• Loading the data into the relational data base tables.

• Working with the Hydrology (HYD)-06 team to document the data set.

• Extracting the standardized data into logical files.

9.2.2 Processing Changes

None given.

9.3 Calculations

Emission rate:

E = C*Q/B

where: C is the concentration of a specific VOC

Q is the flow rate of air through the chamber

B is the dry leaf (needle) biomass of the enclosed branch

Biogenic VOC flux (F):

F = K*(dC/dz)

Page 14
Depositionvelocity(Vd):

Vd = K*(dC/dz)/C

9.3.1 Special Corrections/Adjustments

Peroxide Bias adjustment: C1 = Cl*fb C3 = Cl*fb

where: fb = bias relative to upper sampling level

(range 0.99 to 1.07 for H202, 0.99 to 1.02 for ROOH)

9.3.2 Calculated Variables

None given.

9.4 Graphs and Plots

None.

10 Errors

10.1 Sources of Error

Hydrogen Peroxide (TGB-10b): The following sources of error are those that are not easily

identified, and may affect the data record despite efforts to identify and correct all errors.

• Irregularities in sample line loss (condensation, dirt, bugs).

• Contamination of the switching valve due to bugs, dirt, pollen, etc.

• Irregular signal drift, possibly due to extreme temperature fluctuations.

• Interference due to smoke particles.

Hydroperoxides (TGB- 10c):

• Fluctuations in air flow rate.

• Error in preparing sample volume.

• Fluctuations in sample collection efficiency with temperature.

• Possible condensation in sample lines.

• Interference due to smoke particles.

• Error associated with the serial dilution of H202 standards.

10.2 Quality Assessment

10.2.1 Data Validation by Source

None given.

10.2.2 Confidence Level/Accuracy Judgment

Hydrogen peroxide concentrations are good to approximately 30%. Total organic peroxide

concentrations have not been corrected for collection efficiency. Reported total organic peroxide

concentration may be underestimated by as much as 60%. Individual deposition velocity measurements

are subject to 50-80% uncertainty due to uncertainties in the measured gradient, the measured eddy

diffusivity, and the natural variability of a turbulent atmosphere. Ozone concentrations are good to +/-

5 ppb for IFC-1, and +/- 3 ppb for IFC-2 and IFC-3.

10.2.3 Measurement Error for Parameters

None given.

10.2.4 Additional Quality Assessments

None given.

Page 15
10.2.5 Data Verification by Data Center

BORIS staff processed the data by:

• Reviewing the initial data files and loading them online for BOREAS team access.

• Designing relational data base tables to inventory and store the data.

• Loading the data into the relational data base tables.

• Working with the TGB-10 team to document the data set.

• Extracting the standardized data into logical files.

11. Notes

11.1 Limitations of the Data

Peroxide deposition velocities at OJP are subject to some uncertainty (factor of 2) simply because

we do not know for certain that the application of Kh is appropriate for peroxide transport. The eddy

diffusivity for water vapor over OJP was lower than that of heat. Therefore, average peroxide

deposition velocities should probably be taken as an upper limit.

11.2 Known Problems with the Data

None given.

11.3 Usage Guidance

Peroxide deposition rates are extremely difficult to measure in the field. Individual measurements

of peroxide deposition velocity hold little significance due to the uncertainties mentioned in Section

10.2. However, because of the large amount of data collected, these deposition rates are a valuable

component of the peroxide budget. Vd data should be used to assess average deposition rates to a

rough, boreal pine forest.

11.4 Other Relevant Information

None given.

12. Application of the Data Set

The data can be used to examine (a) the role of biogenic hydrocarbon emissions with respect to carbon

cycles in the boreal forest, (b) the chemical fate of boreal biogenic emissions, (c) the hypothesis that

biospheric VOC emissions contribute to peroxide formation, and (d) the deposition rates of hydrogen

peroxide and organic peroxides.

None.

13. Future Modifications and Plans

14. Software

14.1 Software Description

All software used to gather data were off-the-shelf, standard scientific scientific packages.

14.2 Software Access

None given.

Page 16
15. Data Access

The TGB-10 VOC data are available from the Earth Observing System Data and Information System

(EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

15.1 Contact Information

For BOREAS data and documentation please contact:

ORNL DAAC User Services

Oak Ridge National Laboratory

P.O. Box 2008 MS-6407

Oak Ridge, TN 37831-6407

Phone: (423) 241-3952

Fax: (423) 574-4665

E-mail: ornldaac@ornl.gov or ornl@eos.nasa.gov

15.2 Data Center Identification

Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory

(ORNL) Distributed Active Archive Center (DAAC) for Biogeochemical Dynamics

http://www-eosdis.ornl.gov/.

15.3 Procedures for Obtaining Data

Users may obtain data directly through the ORNL DAAC online search and order system

[http://www-eosdis.ornl.gov/] and the anonymous FTP site [ftp://www-eosdis.ornl.gov/data/] or by

contacting User Services by electronic mail, telephone, fax, letter, or personal visit using the contact

information in Section 15.1.

15.4 Data Center Status/Plans

The ORNL DAAC is the primary source for BOREAS field measurement, image, GIS, and

hardcopy data products. The BOREAS CD-ROM and data referenced or listed in inventories on the

CD-ROM are available from the ORNL DAAC.

16. Output Products and Availability

16.1 Tape Products

None.

16.2 Film Products

None.

16.3 Other Products

These data are available on the BOREAS CD-ROM series.

Page 17
17. References

17.1 Platform/Sensor/Instrument/Data Processing Documentation

None given.

17.2 Journal Articles and Study Reports

Guenther, A. et al. 1996. Isoprene fluxes measured by enclosure, relaxed eddy accumulation, surface

layer gradient, mixed layer gradient, and mixed layer mass balance techniques. Journal of Geophysical

Research, 101, 18,555-18,567.

Hall, B.D. and C.S. Claiborn. 1997. Measurements of the dry deposition of peroxides to a Canadian

boreal forest. Journal of Geophysical Research 102(D24):29,343-29,353.

Kok, G.L., S.E. McLaren, and T.A. Staffelbach. 1995. HPLC determination of atmospheric organic

hydroperoxides. J. Atmos. Ocean Tech., 12, 282-289.

Lazrus, A.L, G.L. Kok, S.N. Gitlin, J.A. Lind, B.G. Heikes, and R.E. Shetter. 1986. Automated

fluorometric method for hydrogen peroxide in air. Anal. Chem. 58, 594-597.

Newcomer, J., D. Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson,

A. Papagno, D. Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers, eds. 2000. Collected Data of The

Boreal Ecosystem-Atmosphere Study. NASA. CD-ROM.

Sellers, P. and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version

1994-3.0, NASA BOREAS Report (EXPLAN 94).

Sellers, P. and F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version

1996-2.0, NASA BOREAS Report (EXPLAN 96).

Sellers, P., F. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994

Operations. NASA BOREAS Report (OPS DOC 94).

Sellers, P., F. Hall, and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996

Operations. NASA BOREAS Report (OPS DOC 96).

Sellers, P., F. Hall, H. Margolis, B. Kelly, D. Baldocchi, G. den Hartog, J. Cihlar, M.G. Ryan, B.

Goodison, P. Crill, K.J. Ranson, D. Lettenmaier, and D.E. Wickland. 1995. The boreal

ecosystem-atmosphere study (BOREAS): an overview and early results from the 1994 field year.

Bulletin of the American Meteorological Society. 76(9): 1549-1577.

Sellers, P.J., F.G. Hall, R.D. Kelly, A. Black, D. Baldocchi, J. Berry, M. Ryan, K.J. Ranson, P.M.

Crill, D.P. Lettenmaier, H. Margolis, J. Cihlar, J. Newcomer, D. Fitzjarrald, P.G. Jarvis, S.T.

Gower, D. Halliwell, D. Williams, B. Goodison, D.E. Wickland, and F.E. Guertin. 1997. BOREAS

in 1997: Experiment Overview, Scientific Results and Future Directions. Journal of Geophysical

Research 102(D24): 28,731-28,770.

17.3 Arehive/DBMS Usage Documentation

None.

None.

18. Glossary of Terms

Page 18
ASCII

BOREAS

BORIS

CD-ROM

DAAC

DNPH

EOS

EOSDIS

GIS

GMT

GSFC

HPLC

HTML

HYD

IFC

NAD83

NASA

NIST

NMHC

NSA

OA

OBS

OJP

ORNL

PANP

REA

SI

SSA

TF

TGB

URL

VOC

WSU

19. List of Acronyms

- American Standard Code for Information Interchange

- BOReal Ecosystem-Atmosphere Study

- BOREAS Information System

- Compact Disk-Read-Only Memory

- Distributed Active Archive Center

- dinitrophenylhydrazine

- Earth Observing System

- EOS Data and Information System

- Geographic Information System

- Greenwich Mean Time

- Goddard Space Flight Center

- High Performance Liquid Chromatography

- Hyper-Text Markup Language

- Hydrology

- Intensive Field Campaign

- North American Datum of 1983

- National Aeronautics and Space Administration

- National Institute for Standards and Technology

- Non-Methane Hydrocarbon

- Northern Study Area

- Old Aspen

- Old Black Spruce

- Old Jack Pine

- Oak Ridge National Laboratory

- Prince Albert National Park

- Relaxed Eddy Accumulation

- System International

- Southern Study Area

- Tower Flux

- Trace Gas Biogeochemistry

- Uniform Resource Locator

- Volatile Organic Compound (or Carbon)

- Washington State University

20. Document Information

20.1 Document Revision Dates

Written: 17-Nov- 1994

Last Updated: 16-Jul- 1999

20.2 Document Review Dates

BORIS Review: 12-Jun-1998

Science Review:

20.3 Document ID

20.4 Citation

When using these data, please contact the individuals listed in Section 2.3 and cite any relevant

papers in Section 17.2.

Page 19
If usingdatafromtheBOREASCD-ROM series,alsoreferencethedataas:

Westberg,H. andN. Hewitt, "Measurementof BiogenicHydrocarbonFluxes."In CollectedData

of TheBorealEcosystem-AtmosphereStudy.Eds.J.Newcomer,D. Landis,S.Conrad,S.Curd,K.

Huemmrich,D. Knapp,A. Morrell, J.Nickeson,A. Papagno,D. Rinker, R.Strub,T. Twine, F.

Hall, andP.Sellers.CD-ROM.NASA, 2000.

Also,citetheBOREASCD-ROMsetas:

Newcomer,J.,D. Landis,S.Conrad,S.Curd,K. Huemmrich,D. Knapp,A. Morrell, J.

Nickeson,A. Papagno,D. Rinker,R.Strub,T. Twine,F. Hall, andP.Sellers,eds.CollectedDataof

TheBorealEcosystem-AtmosphereStudy.NASA. CD-ROM.NASA, 2000.

20.5 Document Curator

20.6 Document URL

Page 20
REPORT DOCUMENTATION PAGE FormApproved

OMB No. 0704-0188

Public reporting burden for this collection of informationis estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources,

gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this

collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson

Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503.

1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED

November 2000 Technical Memorandum

4. TITLE AND SUBTITLE

Technical Report Series on the Boreal Ecosystem-Atmosphere Study (BOREAS)

BOREAS TGB-10 Volatile Organic Carbon Data over the SSA

6. AUTHOR(S)

Hal Westberg, Brad Hall, and Andrea V. Jackson

Forrest G. Hall and Sara K. Conrad, Editors

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS (ES)

Goddard Space Flight Center

Greenbelt, Maryland 20771

9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS (ES)

National Aeronautics and Space Administration

Washington, DC 20546-0001

5. FUNDING NUMBERS

923

RTOP: 923-462-33-01

8. PEFORMING ORGANIZATION

REPORT NUMBER

2000-03136-0

10. SPONSORING / MONITORING

AGENCY REPORT NUMBER

TM--2000-209891

Vol. 243

11. SUPPLEMENTARY NOTES

H. Westberg and B. Hall: Washington State University, Pullman; A.V. Jackson: Lancaster University,

UK; S.K. Conrad: Raytheon ITSS

12a. DISTRIBUTION / AVAILABILITY STATEMENT

Unclassifie_Unlimited

Subject Category: 43

Report available from the NASA Center for AeroSpace Information,

7121 Standard Drive, Hanover, MD 21076-1320. (301) 621-0390.

12b. DISTRIBUTION CODE

13. ABSTRACT (Maximum 200 words)

The BOREAS TGB-10 team collected several trace gas data sets in its efforts to determine the role of

biogenic hydrocarbon emissions with respect to boreal forest carbon cycles. This data set contains

measured VOC concentrations. These data were obtained at the SSA-OJP site from May to September

1994. The data are stored in tabular ASCII files.

14. SUBJECT TERMS

BOREAS, trace gas biogeochemistry.

17. SECURITY CLASSIFICATION

OF REPORT

Unclassified

NSN 7540-01-280-5500

18. SECURITY CLASSIFICATION

OF THIS PAGE

Unclassified

19. SECURITY CLASSIFICATION

OF ABSTRACT

Unclassified

15. NUMBER OF PAGES

2O

16. PRICE CODE

20. LIMITATION OF ABSTRACT

UL

Standard Form 298 (Rev. 2-89)

Prescribed by ANSI Std. Z39.18

298-102