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PEM TROPICS-A Nominal Measurement Characteristics of Instruments on the P-3B

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SPECIES
PARAMETER		 INVESTIGATOR TECHNIQUE AVERAGING TIME ACCURACY NOMINAL
PRECISION		 NOMINAL
LOD
J(NO2) Zenith & Nadir M. Rodgers Actinometer 60 sec NA NA NA
J(O1D) Zenith/Nadir M. Rodgers Actinometer 60 sec. NA NA NA
CO G. Sachse Diode Laser
Specrometer		 5 sec 2% 1 ppbv or 1% NA
CH4 G. Sachse Diode Laser
Specrometer		 5 sec 1% 1 ppbv NA
CO2 B. Anderson NDIR 5 sec 300ppbv 100 ppbv NA
CH3ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
C2H5ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
i-C3H7ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
n-C3H7ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
2-C4H9ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
3-CH3-2-C4H9ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
3-C5H11ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
2-C5H11ONO2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
CH2Cl2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) < 1 ppt
HCFC141B E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
HCFC142B E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
HFC134A E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
CH2Br2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
CHBrCl2 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
CHBr2Cl E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
CHBr3 E. Atlas (1) 10-75 sec 10% - 20% (6) 5% - 10 % (6) <0.1 ppt
H2O2 B. Heikes Grab Samples/HPLC 5 min ±30% 10 pptv 15 pptv
CH3OOH B. Heikes Grab Samples/HPLC 5 min ±30% 15 pptv 25 pptv
OH F. Eisele CIMS 30 sec (7) 20-40% 500000/cm3
H2SO4 F. Eisele CIMS 30 sec (7) 20-40% 200000/cm3
MSA F. Eisele CIMS 30 sec factor of 2 20-40% 500000/cm3
DMS A. Bandy GC/MS 30 sec NA 1 pptv 2 pptv
SO2 A. Bandy GC/MS 30 sec NA 1 pptv 1 pptv
MS B. Huebert Filter Sampling 15-70 min NA NA NA
SO4 B. Huebert Filter Sampling 15-70 min NA NA NA
Na B. Huebert Filter Sampling 15-70 min NA NA NA
NH4 B. Huebert Filter Sampling 15-70 min NA NA NA
NSS B. Huebert Filter Sampling 15-70 min NA NA NA
HNO3 B. Huebert Filter Sampling 15-70 min NA NA NA
Total NO3 B. Huebert Filter Sampling 15-70 min NA NA NA
NH4/NSS Ratio B. Huebert Filter Sampling 15-70 min NA NA NA
H-1301 D. Blake Grab Samples/GC 10-75 sec 5% 2% 0.1
H-1211 D. Blake Grab Samples/GC 10-75 sec 5% 2% 0.1
H-2404 D. Blake Grab Samples/GC 10-75 sec 5% 5% 0.1
HCFC-22 D. Blake Grab Samples/GC 10-75 sec 5% 1.5% 10
F-12 D. Blake Grab Samples/GC 10-75 sec 2% 0.7% 1.0
F-11 D. Blake Grab Samples/GC 10-75 sec 2% 0.8% 3
F-112 D. Blake Grab Samples/GC 10-75 sec 5% 3% 2 pptv
F-113 D. Blake Grab Samples/GC 10-75 sec 2% 1.4% 3
F-114 D. Blake Grab Samples/GC 10-75 sec 5% 1.5% 1
CH3Cl D. Blake Grab Samples/GC 10-75 sec 5% 2% 100
MeBr D. Blake Grab Samples/GC 10-75 sec 5% 5% 1 pptv
CH3I D. Blake Grab Samples/GC 10-75 sec 10% 5-10% (6) 0.05
CHCl3 D. Blake Grab Samples/GC 10-75 sec 5% 2% 2
MeCCl3 D. Blake Grab Samples/GC 10-75 sec NA 5% 2 pptv
CCl4 D. Blake Grab Samples/GC 10-75 sec 5% 1% 3
C2Cl4 D. Blake Grab Samples/GC 10-75 sec 10% 1-5% (6) 0.05
CHCl2Br D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
CH2Br2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.4
CHClBr2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.005
CHBr3 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
MeONO2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
EtONO2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
1-PrONO2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
2-PrONO2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
2-BuONO2 D. Blake Grab Samples/GC 10-75 sec 10-20% (6) 5-10% (6) 0.05
Ethane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 3
Ethene D. Blake Grab Samples/GC 10-75 sec 10% 3 pptv 2
Ethyne D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 2
Propane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 3
Propene D. Blake Grab Samples/GC 10-75 sec 10% 3 pptv 2
i-Butane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 2
n-Butane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 2
i-Pentane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 2
n-Pentane D. Blake Grab Samples/GC 10-75 sec 5% 1% or 2 pptv 2
Isoprene D. Blake Grab Samples/GC 10-75 sec 10% 3% or 3 pptv 2
NO M. Carroll Chemiluminescence 60 sec 7% (3) 20% (3)(4) 4 pptv (2)
O3 M. Carroll Chemiluminescence 1 sec 7% (3)(5) 8% (3) <100 pptv
Total Scatter A. Clarke Nephelometer 15 sec ±2E-7m-1 ±1E-7m-1 2E-7m-1
Submicron Scatter A. Clarke Nephelometer 15 sec ±2E-7m-1 ±1E-7m-1 2E-7m-1
Ultrafine CN (3025) A. Clarke CN Counter 15 sec 5% 5% particles/cm3
CN (3010) A. Clarke CN Counter 15 sec 5% 5% particles/cm3
CN (3760 @30 deg C) A. Clarke CN Counter 15 sec 5% 5% particles/cm3
CN (3760 @300 deg C) A. Clarke CN Counter 15 sec 5% 5% particles/cm3
Dry CN, Surface Area
Volume		 A. Clarke RDMA 40 sec 20% 5% .007<Dp<.148 m
Dry CN, Surface Area
Volume		 A. Clarke OPC 60 sec 15% 5% 0.148<Dp<6m
U Wind Component B. Anderson TAMMS 20 Hz 0.3 m/s 0.5 m/s 0.5 m/s
V Wind Component B. Anderson TAMMS 20 Hz 0.3 m/s 0.5 m/s 0.5 m/s
W Wind Component B. Anderosn TAMMS 20 Hz 0.1 m/s 0.2 m/s 0.2 m/s
Dew Point J. Barrick Cryogenic Chilled Mirror Hygrometer 1 sec ±0.5 - 1.0 OC ±0.2 OC -100 OC
UV Radiation/ Zenith & Nadir J. Barrick Eppley Radiometer 1 sec ±5% ±2% NA
Surface Temperature J. Barrick Pyrometer 1 sec ±0.5 OC ±0.2 OC -50 OC
Dew Point J. Barrick 2 & 3 Stage Frost Point Hygrometer 1 sec ±0.5 - 1.0 OC ±0.2 OC -100 OC
Aircraft Ephemeris Data J. Barrick GPS 1 sec ±25m ±25m 1m


NOTES:

(1) Trace gas data are based on measurements of whole air samples collected by D. Blake. The analytical technique was gas chromatography with mass spectrometric (EI and NICI) detection.

(2) The detection limit corresponds to 3 times the background level. Random fluctuation in zero, measure and artifact are all included.

(3) Errors correspond to one sigma values.

(4) Approximately half of uncertainty in precision is due to uncertainty in the artifact.

(5) During flights 4, 6 & 7, an instrument malfunction caused a systematic error of uncertain magnitude. The reported mixing ratios for ozone are lower than the real mixing ratios. Most likely the numbers are 2.5% to 20% low. There is a small chance that the reported mixing ratios are off by more than 20% but they cannot be more than 39% low. During flight 8 a similar problem occurred. Most likely the reported mixing ratios are <1% to 5% low. There is a small chance that they can be off by more than 5% but they cannot be more than 10% low.

(6) Higher uncertainty for molecules with mixing ratios in the 0.001 - 0.1 pptv range

(7) Reported error limits are +/- 42.0% for measurements made at pressures above 940 mBar, and +/- 62.0% for measurements made below 940mBar. The quoted errors are 2 sigma. A few of the later flights (14-17) were plagued with detector problems which greatly enhanced scatter in the measured data. This scatter should not significantly alter the uncertainty of the data except that a larger number of data points must be averaged to reduce the scatter in this data. The reported error for flights 14-17 is +/- a factor of two for measurements made at pressures above 940 mBar and an additional 20% for meassurements made below 940 mBar. The increase in uncertainty at higher altitudes reflects the increased spread in the observed calibration coefficients and the increased uncertainty in the concentration of H2O at higher altitudes.


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