Vertical Boundary Layer Profiles for Ozone and Meteorological Parameters at Summit, Greenland, 2000

Summary

This data set contains ozone surface data, 133 meteorological, and 82 ozone vertical profile measurements collected from the surface to a maximum altitude of 1400 meters above the ground surface in Summit, Greenland. The data were collected from a tethered balloon platform in June 2000.

This research was funded by the National Science Foundation, grant number OPP-0097147.

Citing These Data

Helmig, D. 2004. Vertical Boundary Layer Profiles for Ozone and Meteorological Parameters at Summit, Greenland, 2000. Boulder, CO: National Center for Atmospheric Research.

Please contact the Principal Investigator (PI) before including any of the data in publications.

Overview Table

Category Description
Data format Microsoft Excel
Spatial coverage and resolution Summit Greenland, 72.55°N and 38.4°E, 3200 m above sea level
Temporal coverage 2000-06-04 to 2000-06-21
File naming convention Type of data collected and flight number
File size 53 KB to 1.8 MB
Parameter(s) Height, ozone mixing ratio, pressure, temperature, relative humidity, wind direction, wind speed
Procedures for obtaining data Data are available for ordering from NCAR.

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information

1. Contacts and Acknowledgments

Investigator(s) Name and Title

Dr. Detlev Helmig
INSTAAR
University of Colorado
1560 30th Street
Boulder, CO 80309
USA

David Boulter
1560 30th Street
Boulder, CO 80309
USA

Donald James
1560 30th Street
Boulder, CO 80309
USA

Technical Contact

2. Detailed Data Description

Format

Each profile is in a separate Excel file. Please note that these files were created using Microsoft Excel 2002. Future versions of Excel may not be able to read these files.

File Naming Convention

Individual data files are named according to the type of data collected and the flight number.

eco: electro-chemical ozone measurements
met: meteorological measurements

For example, eco3_flght#21_2.xls contains electrochemical ozone data from flight number 21.

File Size

Individual file sizes range from 53 KB to 1.8 MB.

Spatial Coverage

The data were collected from Summit, Greenland, 72.55°N and 38.4°E, at 3200 m above sea level. The maximum altitude of data collection was 1400 m above ground.

Temporal Coverage

The data collection period was from 2000-06-04 to 2000-06-21.

Parameter or Variable

Parameter Description

The parameters measured were height, ozone mixing ratio, pressure, temperature, relative humidity, wind direction, and wind speed.

Sample Data Record

The following sample data is from the file eco3_flght#17_2.xls.

Flight #: 17
Ground P 684.5 684.5
Grd T_pre -16
Grd T_pst -19.5
Grd O3_pre 63.5
Grd O3_pst 64.5

Local Time

Press

T

Pot. T

RH

Frost Pt

Ozone

Ozone

Ozone

Pump

Height

 

 

 

 

 

 

mPa

ppm

ppb

T

 

19:37:41 1177.7

684.62

-16.37

286.2

51

-21.69

3.47

5.07E-02

50.7

16.14

-1

19:37:49 1177.8

684.72

-16.4

286.1

50.9

-21.74

3.534

5.16E-02

51.6

16.16

-2

19:37:56 1177.9

684.72

-16.46

286.1

50.8

-21.8

3.588

5.24E-02

52.4

16.16

-2

19:38:04 1178.1

684.65

-16.43

286.1

50.9

-21.75

3.624

5.29E-02

52.9

16.16

-2

3. Data Access and Tools

Data Access

Data are available for ordering from NCAR. Please contact the PI before using any of these data for some additional information on quality assurrance.

4. Data Acquisition and Processing

Sensor or Instrument Description

Two tethered helium balloons were used for the profiling experiments.

Ozone was measured using EN-SCI Model 2Z (EN-SCI Corporation, Boulder, CO) electrochemical concentration cell (ECC) sondes (Komhyr 1969).

Two TSP-5A-SP Vaisala tethersondes and two RS-80 Vaisala radiosondes were used for the measurement of meteorological parameters along vertical profiles with the balloon.

See Data Acquisition Methods below for details on these instruments and how they were used to collect data.

Data Acquisition Methods

Tethered Balloon Platform

Two tethered helium balloons were used for the profiling experiments. A 3-ply 18-foot blimp (Floatograph Technologies, Napa, CA) was used initially but provided insufficient lift for the equipment package. A second balloon proved to work under the extreme conditions of high wind shear and low temperatures at Summit. This balloon (Sky-Doc, Floatograph Technologies) combines properties of a kite and a helium balloon. The Sky-Doc has a flattened, round shape; a sail at the back of the balloon's disk causes the front of the balloon to face into the prevailing wind, and as the wind speed increases, lifts the nose of the balloon upwards, projecting an increased cross-sectional area toward the wind. In this manner, some degree of the blimp-like character is exchanged for a kite-like character in high winds. The subsequent increase in lift counteracts the tendency of conventional blimps to lose stability and lift under high wind conditions. The 18-foot Sky-Doc always had a lift in excess of 10 kg, which was more than sufficient to simultaneously deploy all of the meteorological and chemical instruments. An 800-pound breaking strength Kevlar line was used. Balloon ascent and descent were controlled with a hydraulic winch.

Ozone Measurements

Two types of instruments were used for ozone measurements from the balloon. Ozone was measured using EN-SCI Model 2Z (EN-SCI Corporation, Boulder, CO) electrochemical concentration cell (ECC) sondes (Komhyr 1969), which are based on the principle that ozone and iodide react within an electrochemical cell. The ECC ozone sondes were interfaced to a RS-80 (Vaisala, Helsinki, Finland) radio sonde and data were transmitted to a ground receiver. A total of five ECC sondes were used during the field experiment. Sondes had previously been used in other field experiments and were thoroughly reconditioned and tested prior to field deployment. All sondes met the following performance criteria:

Electrochemical cells were filled with de-ionized water during shipment and when not in use at the site. A non-buffered 2 % KI aqueous solution was used as cathode solution (Johnson et al., 2001). In addition to ECC sondes, a 2B Technologies (Golden, CO) instrument was deployed during the latter part of the experiment. This instrument is a miniaturized single-beam UV absorption instrument that can be battery operated. An earlier version of this instrument has been described by Bognar and Birks (1996). The instrument weighed 0.8 kg (without the standard instrument housing), was powered by a 12 V lead-acid battery (0.55 kg) and enclosed in a 3 cm thick Styrofoam container. Data were recorded every 10 s. Ozone mixing ratios were stored on an internal data logger and downloaded to a computer upon landing. Raw data were averaged using a 7-point moving average. Intercomparison results between the ECC sondes and UV instrument were presented by Boulter et al. (2000).

Meteorological Measurements

Two TSP-5A-SP Vaisala tethersondes and two RS-80 Vaisala radiosondes were used for the measurement of meteorological parameters along vertical profiles with the balloon. The RS-80 radiosonde measured pressure (aneroid capacitor), temperature (bead capacitor) and relative humidity (thin film capacitor). Every 8 seconds the radiosonde transmitted data from all sensors to a ground receiver, which was interfaced to a laptop computer for data acquisition. The TSP-5A-SP tethersonde measured pressure (electronic aneroid capacitance sensor), temperature (fast response bead thermistor), relative humidity (fast response capacitance polymer sensor), wind speed (three-cup anemometer with light-chopper tachometer) and wind direction (electronically controlled magnetic compass). Data from the tethersonde was acquired in 1.25-second intervals and recorded during flight on 90-min audio tapes with a small tape recorder attached to the tether line about 1 m below the sonde. After the flight the data were decoded with an analog-digital board (Vaisala) and stored on a laptop computer. Ozone and meteoro- logical instruments were attached to the balloon tether line within a few meters distance. Pressure readings from the meteorological sondes were used to determine the measurement altitude. Radiative fluxes of short and long-wave radiation were measured with two Kipp and Zonen (Delft, Holland) pyranometers (CM21) and two pyrgeometers (CG4) from a meteorological tower approximately 150 m from the balloon launch site. The instruments were housed in a heated ventilation unit (Kipp and Zonen CV2) 2 m above the snow surface, sampled at 1 Hz and averaged every 10 minutes.

5. References and Related Publications

Bognar, J.A. and J.W. Birks. 1996. Miniaturized ultraviolet ozonesonde for atmospheric measurements. Analytical Chemistry 68 (17): 3059-3062.

Boulter, J., Helmig, D., David, D., Birks, J., Johnson, B., and S. Oltmans. 2000. Ozone profile measurements within the planetary boundary layer at Summit, Greenland: an intercomparison of electrochemical and UV absorbance techniques. Eos Transactions, AGU Vol 81, No. 48, November 28. Abstract A22C-25.

Helmig D., Boulter J., David D., Birks J.W., Cullen N.J., Steffen K., Johnson B.J., and J.W. Oltmans. 2002. Ozone and meteorological boundary-layer conditions at Summit, Greenland, during June 3-12, 2000. Atmospheric Environment 36: 2595-2608.

Johnson, B.J., S.J. Oltmans, H. Vömel, T. Deshler, and C. Kroger. 2001. ECC ozonesonde pump efficiency measurements and tests on the sensitivity to ozone of buffered and unbuffered ECC sensor cathode solutions. Journal of Geophysical Research, accepted, 2001.

Komhyr, W.D. 1969. Electrochemical concentration cells for gas analysis. Annals of Geophysical 25: 203-210.

6. Document Information

Document Creation Date

2002-05-10

Document URL

http://data.eol.ucar.edu/codiac/dss/id=106.ARCSS100