GACP Datasets
NOAA PMEL In-situ Aerosol Data Base Dataset
Contacts:
Tim Bates (bates@pmel.noaa.gov)
Trish Quinn (quinn@pmel.noaa.gov)
Measurement Approach
- Local contamination is avoided by using a sector-controlled inlet. Local wind speed, wind direction, and particle concentration are used to determine sampling periods.
- The sampled aerosol is dried to a reference RH in order to maintain constant instrumental cut sizes through variations in RH. In this way, data obtained from all instruments are directly comparable.
- All chemical measurements are performed on size segregated aerosol thus recognizing the strong dependence of aerosol optical properties on particle size.
Temporal and Spatial Coverage Dataset
| Cruise (Research Vessel) | Date | Location |
|---|---|---|
| PSI-3 (1991) | 15 April 1991 | Seattle, WA |
| (Discoverer) | Washington Coast | |
| 1 May 1991 | Seattle, WA | |
| RITS-1992 | 21 February 1992 | Los Angeles, CA . |
| (Vickers) | 11-12 March 1992 | Marquesas Is. |
| (IGAC-MAGE) | 25 March 1992 | Los Angeles, CA |
| RITS-1993 | 20 March 1993 | Punta Arenas, Chile |
| (Surveyor) | 24-25 March 1993 | Palmer Station, Antarctica |
| 1 April 1993 | 68°S, 140°W | |
| 15-19 April 1993 | Papeete, Tahiti | |
| 4 May 1993 | 54°N, 140°W | |
| 7 May 1993 | Seattle, WA | |
| RITS-1994 | 20 November 1993 | Seattle, WA |
| (Surveyor) | 23 November 1993 | 55°N, 140°W |
| 13-17 December 1993 | Papeete, Tahiti | |
| 28 December 1993 | 68°S, 130°W | |
| 3-4 January 1994 | Palmer Station, Antarctica | |
| 7 January 1994 | Punta Arenas, Chile | |
| ACE-1 (1995) | 11 October 1995 | Seattle, WA |
| (Discoverer) | 19 October 1995 | Honolulu, HI |
| 30 October 1995 | 30°S, 160°W | |
| 10-15 November 1995 | Hobart, Australia | |
| 13 December 1995 | Hobart, Australia | |
| CSP-1 (1996) | 14 March 1996 | American Samoa |
| (Discoverer) | 17 March 1996 | 2°S, 180°W |
| 27-31 March 1996 | 2°S, 147°E | |
| 8 April 1996 | 1°S, 180°W | |
| 13 April 1996 | Honolulu, HI | |
| ACE-2 (1997) | 19 June 1997 | Lisbon, Portugal |
| (Vodyanitskiy) | 8-15°W, 29-41°N | |
| 24 July 1997 | Lisbon, Portugal | |
- PSI - Pacific Sulfur/Stratus Investigation (1991)
- RITS - Radiatively Important Trace Species (1992, 1993, 1994)
- IGAC-MAGE - International Global Atmospheric Chemistry Program's Marine Aerosol and Gas Exchange Equatorial Pacific Experiment (1992)
- ACE - IGAC Aerosol Characterization Experiment (1995, 1997)
- CSP - Combined Sensor Program (1996)
Measured Properties Dataset
Aerosol Physical Properties
| Property | Symbol | Method |
|---|---|---|
| Number concentration | N | Dp > 3 nm, UCPCa Dp > 12 nm, CPCb |
| Number size distribution | dN/dlogDp | 5 < Dp < 28 nm: DMPSc 20 < Dp < 600 nm: DMPSd 0.5 < Dp < 10 μm: APSe |
Aerosol Chemical Properties
| Property | Symbol | Method |
|---|---|---|
| Chemical mass size distribution | dm/dlogDp | Collection with impactor followed by chemical analysis for ionsf, elemental and organic carbong, total massi |
| Refractive index | m | Chemical equilibrium model |
| Density | ρ | Chemical equilibrium model |
Aerosol Optical Properties
| Property | Symbol | Method |
|---|---|---|
| Scattering coefficient | σsp (λ) | Integrating nephelometer 450, 550, and 650 nm |
| Backscattering coefficient | σbsp (λ) | Integrating nephelometer 450, 550, and 650 nm |
| Backscattered fraction | b | |
| Absorption coefficient for soot aerosol | σap (λ) | PSAPj at 550±20 nm |
| Scattering phase function | f(λ, q ) | Mie calculation |
| Asymmetry parameter | g | Mie calculation |
| Single scattering albedo | ωo | Mie calculation |
| Mass scattering efficiency of component i | αsp,i | Mie calculation |
| Particle optical depthk | δp(λ) | Sunphotometer |
a-ultra-fine condensation particle counter
b-condensation particle counter
c-ultra-fine differential mobility analyzer and UCPC
d-differential mobility analyzer and CPC
e-aerodynamic particle sizer
f-ion chromatography
g-thermo-optical techniques (ACE 2 only)
i-gravimetry
j-particle soot absorption photometer
k-available for RITS 93 (390 and 500 nm), RITS 94 (380 and 500 nm), ACE 1
(380, 500, 672, and 778 nm)
Data Format
Data are available as ASCII files. ACE 1 data are available at the ACE 1 project page at UCAR/OFPS (http://www.ofps.ucar.edu/cgi-bin/codiac/projs?ACE-1). All other data sets are available from NOAA PMEL.
