what we want to do how we plan to do it - nasa...pride_airbornesunphotvgs.doc 8 p. russell, 7/11/00...

PRIDE_AirborneSunphotVGs.doc 1 P. Russell, 7/11/00

Airborne Sunphotometry and Integrated Analysesof Dust, Other Aerosols, and Water Vapor in the

Puerto Rico Dust Experiment (PRIDE)

Philip B. Russell,NASA Ames Research Center, Moffett Field, CA

Co-Investigators:Beat Schmid 1, Jens Redemann 1, John M. Livingston 2, Peter Pilewskie 3

1Bay Area Environmental Research Institute, San Francisco, CA2SRI International, Menlo Park, CA

3NASA Ames Research Center, Moffett Field, CA

A proposed investigation presented at

PRIDE VideoconNASA Goddard and Ames

24 January 2000

What we want to do&

How we plan to do it


Task 1. Install AATS-6 on the SPAWAR Navajo

DomeRadius = 4”

AATS = Ames Airborne Tracking Sunphotometer


How AATS-14 flew in TARFOX and ACE-2SunphotometerDome radius = 4”

Next Tasks: Address Yoram’s Lists


Yoram’s Lists*What to measure in PRIDE:

• Spectral optical thickness under Terra over glintfree and glint regions

• Ground based measurements of dust absorption,scattering and iron concentration during a givenperiod of time

• Vertical profiles of whatever we can measure

• Ocean spectral propertiesWhy:

• Dust is most abundant aerosol, yet its propertiesleast known. What can we measure?

• Dust fertilizes the ocean. What is the relationshipbetween the dust optical thickness, absorptionand iron concentration ? How variable is it?

• Need to know how badly dust (aspherical,inhomogeneous) degrades MODIS and otherretrievals (which assume spherical homogeneousparticles).

• In coastal regions, need to know how badlyunderwater reflection degrades MODIS retrievals.

• The best dust measurements are from groundbased instrumentation. How representative arethey of the vertical column?

*Yoram Kaufman’s email of 1/17/00


Example:AATS-6 continuous transect of multi- λ AOD

demonstrates quantitatively how ATSR-2retrieval accuracy exceeds AVHRR

Veefkind et al., JGR, 1999


Example:AATS-6 underflights of MODIS Airborne Simulator

(MAS) quantify how MAS retrieval accuracydepends on AOT magnitude

0.01

0.10

1.00

0.2 0.4 0.6 0.8 1.0 3.0

17 July 96

MAS/Track 10MAS/Track 11MAS/Track 12AATS-6

Aer

osol

Opt

ical

Thi

ckne

ss

Wavelength (µm)

0.01

0.10

1.00

0.2 0.4 0.6 0.8 1.0 3.0

20 July 96MAS/Track 04AATS-6

Aer

osol

Opt

ical

Thi

ckne

ss

Wavelength (µm)

Tanre et al., JGR, 1999


Yoram’s Lists*What to measure in PRIDE:

• Spectral optical thickness under Terra over glintfree and glint regions

• Ground based measurements of dust absorption,scattering and iron concentration during a givenperiod of time

• Vertical profiles of whatever we can measure

• Ocean spectral propertiesWhy:

• Dust is most abundant aerosol, yet its propertiesleast known. What can we measure?

• Dust fertilizes the ocean. What is the relationshipbetween the dust optical thickness, absorptionand iron concentration ? How variable is it?

• Need to know how badly dust (aspherical,inhomogeneous) degrades MODIS and otherretrievals (which assume spherical homogeneousparticles).

• In coastal regions, need to know how badlyunderwater reflection degrades MODIS retrievals.

• The best dust measurements are from groundbased instrumentation. How representative arethey of the vertical column?

*Kaufman email, 1/17/00


Example:AATS-6 and -14 AOD spectra and

continuous vertical profiles quantify how dustchanges bias of AVHRR retrievals

AATS-6 (ship)AATS-14 (plane)AVHRR (ship loc)AVHRR (plane loc)

1515 UTC

1514-1516 UTC

1457-1500 UTC

0

1

2

3

4

0 0.05 0.1 0.15 0.2

ALT

ITU

DE

(km

)

(d) 17 July 97

AEROSOL EXTINCTION (1/km)

380.3

1557.5 864.4

499.4

0.45

0.3 1.0 2.0

AE

RO

SO

L O

PT

ICA

L D

EP

TH

AVHRR (1535 UTC)

AATS-14 (1606 -1621 UTC)

(c) 17 July 97

0.40

0.30

0.5 0.7

0.45

0.25

WAVELENGTH (µm)

AATS-14 (1525 -1606 UTC)

0

1

2

3

4

0 0.1 0.2 0.3

ALT

ITU

DE

(km

)

0.3 1.0 2.0

AE

RO

SO

L O

PT

ICA

L D

EP

TH

WAVELENGTH (µm)

(a) 10 July 97

0.5 0.7

(b) 10 July 97

AEROSOL EXTINCTION (1/km)

380.3

1557.5

864.4

499.4

AATS-14 (1500 -1603 UTC)

0.24

0.22

0.20

0.18

0.16

0.14

0.12

0.10

0.08

0.06

Livingston et al., Tellus , 2000; Schmid et al., Tellus , 2000


We need many comparisons to see if thedust/no-dust difference is statistically stable

0.3 0.4 0.5 0.6 0.8 1.0 1.3 1.60.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.220.24

Aer

osol

Opt

ical

Dep

th

AATS-6: 1514-1516 UTCAATS-14: 1457-1500 UTCAVHRR (ship loc): 1515 UTCAVHRR (plane loc): 1515 UTC

Wavelength [µm]

(c)

July 10, 1997

Dustabsent

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.2 1.4 1.60.25

0.3

0.35

0.4

0.45

0.5

Aer

osol

Opt

ical

Dep

th

AERONET 630nm

Sagres 860nmSagres 630nmAATS-6 860nmAATS-6 630nmAATS-14 860nmAATS-14 630nmAERONET 860nm

Sat

ellit

e O

ptic

al D

epth

Ret

rieva

l

0.5

0.4

0.3

0.2

0.1

0.00.0 0.1 0.2 0.3 0.4 0.5

Surface Optical Depth Measurements

Wavelength [µm]

Dustpresent

Dustabsent

(a)

(b)

AATS-14: 16.13-16.35 UTAVHRR: 15.58 UT

July 17, 1997

Dustpresent

Durkee et al., Tellus , 2000Livingston et al., Tellus , 2000; Schmid et al., Tellus , 2000


The cardinal rule of satellite validation

Whenever possible, use validation instruments andmethods that have a proven track record:

- Error bars based on acomprehensive erroranalysis

- History of successfulintercomparisons to otheraccepted techniques

}Documentedin the peer-reviewedliterature


The cardinal rule of satellite validation

Whenever possible, use validation instruments andmethods that have a proven track record:

- Error bars based on acomprehensive erroranalysis

- History of successfulintercomparisons to otheraccepted techniques

}Documentedin the peer-reviewedliterature

Rule 2:

Demand spatiotemporal coincidence betweensatellite data and validation data.

(We live in a very inhomogeneous, changing world.)

- Mobility & spatiotemporal continuity ofvalidation measurements really help to achievethis coincidence


We’ve demonstrated lots of othermeasurements and collaborativeanalyses that would be useful in

PRIDE

• Ways to get absorption (see Yoram’s list) of theambient, unperturbed aerosol:- AATS vertical profiles in the MicroPulse Lidar

(MPL) beam, to get B/E(z); hence ω(z)(Redemann et al., 2000; Schmid et al., 2000;Welton et al., 2000)

- Combine SSFR Flux(z, λ) with AATS AOD(z, λ) toget diffuse/direct Flux(z, λ); hence ω(λ) (Russellet al., 1999b)

• Many comparisons to airborne in situmeasurements, to test closure:- AOD(λ) from AATS, nephelometer, PSAP, size

spectrometers, chemistry(r) (Schmid et al.,2000; Collins et al., 2000; Livingston et al., 2000)

- n(r) from AATS vs size spectrometers(corrected for inlet losses, evaporation,calibration, etc.) (Schmid et al., 2000)

• Water vapor column from AATS (Livingston et al.,2000):- Compare to satellite retrievals; test correlation

with AOD retrieval errors- Study effect on aerosol size, composition


0

1000

2000

3000

4000

0.8 0.82 0.84 0.86 0.88 0.9 0.92 0.94 0.96 0.98 1

Alti

tude

[m]

Single-scattering albedo

This study

Hartley et al.

Aerosol single-scattering albedo profiles determined for TARFOX flight 1728 (July 17, 1996) by two techniques.Solid line: derived by Redemann et al. (2000b) using in situ particle size distributions and aerosol layer complexrefractive index estimates from Redemann et al. (2000a) that produce best agreement among profiles of lidarbackscatter, sunphotometer extinction, and relative size distribution. Values were used in the first band of theFu-Liou radiative transfer model (0.2 µm < λ < 0.7 µm). Dashed line: derived by Hartley et al. (2000) at 450 nmby combining in situ scattering, absorption, and size distribution measurements. The gray-shaded area representstheir uncertainty estimates based on one standard deviation plus instrumental error.


0 0.1 0.2 0.3 0.4 0.5-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

1.00 0.935 0.86

Aerosol Optical Depth (300-700 nm) Above Measurement ________

24

hr

avg

.∆F

↓ (

W m

-2)

(b)

ω(550)=

ω(550)=

1.00

0.935

0.86

↑←

↓

←

↓←

Calc.Meas.

July 27

July 25

Comparison between aerosol-induced change in downwelling solar flux derived from C-130 pyranometermeasurements (data points) and calculated (curves) for size distributions retrieved from sunphotometer opticaldepth spectra using an aqueous sulfate real refractive index and a range of imaginary indexes to give the ω (550)values shown. The error bar (cross) shows the uncertainty in flux change and broadband visible optical depthdetermined from the C-130 pyranometer measurements (Russell, et al., 1999b).


Comparison of aerosol optical depth spectra for the marine boundary layer (31-1111 m) during Pelican flighttf20 in ACE 2 on July 8, 1997 (Schmid et al., 2000).

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.2 1.4 1.60.02

0.03

0.04

0.05

0.06

0.07

0.08

0.090.1

0.12

0.14

Wavelength [µm]

Laye

r A

eros

ol O

ptic

al D

epth

Layer: 0.031−1.111 km

ACE−2 8. 7.1997

AATS−14 Caltech OPC UW Neph+PSAP MISU Neph+PSAP


Comparison of marine boundary layer aerosol size distributions from in situ measurements and inverted fromAATS-14 extinction spectra measured on Pelican flight tf15 in ACE 2 on July 17, 1997. Dashed lines indicateuncertainty of the in situ results (Schmid et al., 2000).

0.01 0.02 0.05 0.1 0.2 0.5 1 2 4 8 120

50

100

150

200

250

300

350

400

450

500

55017 July 97, MBL 203−882m

D [µm]

dS/d

logD

[µm

2 cm

−3 ]

AATS−14 Caltech OPC


0 0.5 1 1.5 2 2.50

0.5

1

1.5

2

2.5

3

3.5

4

Columnar Water Vapor [g/cm2]

Alti

tude

ACE−2 17. 7.1997 15.42−16.1 UT

−5 0 5 10 15 200

0.5

1

1.5

2

2.5

3

3.5

4

Water Vapor Density [g/m3]

Alti

tude

AATS−14 Humidograph

Left panel: Profile of the columnar water vapor above the Pelican aircraft measured in ACE-2 south of the coastof Tenerife. Right panel: Water vapor density derived by differentiating the profile in the left panel. Also shownfor comparison is the profile obtained by combining readings of a humidograph and outside temperature onPelican (humidograph data courtesy of S. Gasso, University of Washington). (Schmid et al., 2000)


Scatter diagram of columnar water vapor calculated from radiosonde measurements and from AATS-6measurements during ACE-2. Each AATS-6 data point represents the mean calculated over the time periodspanned by the radiosonde measurements; horizontal bars show the corresponding standard deviation (wide ticks)and the range (narrow ticks) for that time period (Livingston et al., 2000).

1.5 2 2.5 3 3.51.5

2

2.5

3

3.5R

adio

sond

e C

olum

nar

Wat

er V

apor

(g/

cm2 )

AATS−6 Columnar Water Vapor (g/cm2)

r2: 0.98

rms diff: 0.10 g/cm2

6/24

6/25

7/6

7/10

7/187/18

7/22

7/22


Vertical profiles of aerosol extinction are obtainedby vertically differentiating AATS continuous

vertical profiles of AOD

380 nm 500 nm 864 nm1558 nm

380 nm 500 nm 864 nm1558 nm

1558 nm

Left panel: Profiles of aerosol optical depth at four selected AATS-14 wavelengths (380, 500, 864 and 1558 nm)measured in ACE-2 south of the coast of Tenerife. Right panel: Aerosol extinction profiles derived bydifferentiating the profiles in the left panel. (Schmid et al., 2000b)


TARFOX and ACE-2 Papers That Use Data from the Ames Airborne Tracking Sunphotometers(AATS-6 and AATS-14)

Bergstrom, R. W., and P. B. Russell, "Estimation of aerosol radiative effects over the mid-latitude North Atlanticregion from satellite and in situ measurements." Geophys. Res. Lett., 26, 1731-1734, 1999.

Collins, D. R., Jonsson, H. H., Flagan, R. C., Seinfeld, J. H., Noone, K. J., Ostrom, E., Hegg, D. A., Gasso, S.,Russell, P. B., Livingston, J. M., Schmid, B., and Russell, L. M., In situ aerosol size distributions and clearcolumn radiative closure during ACE-2, Tellus, in press, 2000.

Durkee, P. A., K. E. Nielsen, P. B. Russell, P. B., B. Schmid, J. M. Livingston, D. Collins, , R. Flagan, J. Seinfeld,K. Noone, S. Gasso, D. Hegg, T. S. Bates, and P. K. Quinn, “Regional aerosol properties from satelliteobservations: ACE-1, TARFOX and ACE-2 results.” J. Aerosol Sci. 29(Suppl 1): S1149, 1998.

Durkee, P. A., Nielsen, K. E., Russell, P. B., Schmid, B., Livingston, J. M., Collins, D., Flagan, R. C., Seinfeld, H.H., Noone, K. J., Ostrom, E., Gassó, S., Hegg, D., Bates, T. S., Quinn, P. K., and Russell, L. M. this issue.Regional aerosol properties from satellite observation: ACE-1, TARFOX and ACE-2 results. Tellus B in press,2000.

Ferrare, R., S. Ismail, E. Browell, V. Brackett, S. Kooi, M. Clayton, S. H. Melfi, D. Whiteman, G. Schwemmer, K.Evans, P. Russell, J. Livingston, B. Schmid, B. Holben, L. Remer, A. Smirnov, P. Hobbs, Comparisons ofaerosol optical properties and water vapor among ground and airborne lidars and sun photometers duringTARFOX, J. Geophys. Res., in press, 2000.

Ferrare, R., S. Ismail, E. Browell, V. Brackett, S. Kooi, M. Clayton, P. Hobbs, S. Hartley, J.P. Veefkind, P. Russell,J. Livingston, D. Tanre, P. Hignett, Comparisons of LASE, aircraft, and satellite measurements of aerosol opticalproperties and water vapor during TARFOX, J. Geophys. Res., in press, 2000.

Hartley, W. S., P. V. Hobbs, J. L. Ross, P. B. Russell and J. M. Livingston, Properties of aerosols aloft relevant todirect radiative forcing off the mid-Atlantic coast of the United States, J. Geophys. Res. (2nd Special Issue onTARFOX), in press, 2000.

Hegg, D. A., J. Livingston, P. V. Hobbs, T. Novakov, and P. B. Russell, Chemical apportionment of aerosolcolumn optical depth off the Mid-Atlantic coast of the United States, J. Geophys. Res, 102, 25,293-25,303,1997.

Hobbs, P. V., T. Novakov, P. Russell, J. M. Livingston, and J. L. Ross, “Relative contributions of atmosphericaerosol constituents to optical depths and direct radiative forcing on the United States east coast.” J. AerosolSci. 29(Suppl 1): S1297-S1298, 1998.

Ismail, S., E.V. Browell, R. Ferrare, S. A. Kooi, M. Clayton, V. Brackett, P. Russell, LASE Measurement ofAerosol and Water Vapor Profiles Measured During TARFOX, J. Geophys. Res., submitted 1999.

Livingston, J. M., V. Kapustin, B. Schmid, P. B. Russell, P. A. Durkee, T. S. Bates, and P. K. Quinn, “Shipboardsunphotometer measurements of aerosol optical depth spectra and columnar water vapor during ACE-2, J.Aerosol Sci. 29(Suppl 1): S257-S258, 1998.

Livingston, J. M., Kapustin, V. N., Schmid, B., Russell, P. B., Quinn, P. K., Timothy, S. B., Philip, A. D., andFreudenthaler, V. this issue. Shipboard sunphotometer measurements of aerosol optical depth spectra andcolumnar water vapor during ACE-2. Tellus B in press, 2000.

Pilewskie, P., M. Rabette, R. Bergstrom, J. Marquez, B. Schmid, and P. B. Russell, The discrepancy betweenmeasured and modeled downwelling solar irradiance at the ground: Dependence on water vapor, Geophys. Res.Lett, 27, 137-140, 2000.

Powell, Donna M., John A. Reagan, Manuel A. Rubio, Wayne H. Erxleben, James D. Spinhirne, ACE-2 MultipleAngle Micro-Pulse Lidar Observations from Las Galletas, Tenerife, Canary Islands, Tellus, in press, 2000.

Redemann, J., R. Turco, Liou, Russell, Bergstrom, Schmid, Livingston, Hobbs, Hartley, Ismail, Ferrare, Browell,Retrieving the Vertical Structure of the Aerosol Complex Index of Refraction From Aerosol In Situ and RemoteSensing Measurements During TARFOX, J. Geophys. Res., in press, 2000.

Redemann, J., R. Turco, Liou, Russell, Bergstrom, Hobbs, Browell, Case Studies of the Vertical Structure of theDirect Aerosol Radiative Forcing During TARFOX, J. Geophys. Res., in press, 2000.

Russell, P. B., and J. Heintzenberg, An overview of the ACE-2 Clear Sky Column Closure Experiment(CLEARCOLUMN), Tellus, in press, 2000.

Russell, P. B., P. Hignett, J. M. Livingston, B. Schmid, A. Chien, P. A. Durkee, P. V. Hobbs, T. S. Bates, and P. K.Quinn, Radiative flux changes by aerosols from North America, Europe, and Africa over the Atlantic Ocean:Measurements and calculations from TARFOX and ACE 2. Fifth International Aerosol Conference, Edinburgh,Scotland, 14-18 September 1998, J. Aerosol Sci. 29(Suppl 1): S255-S256, 1998.


Russell, P. B., J. M. Livingston, B. Schmid, A. Chien, S. Gasso, D. Hegg, K. Noone, D. Collins, H. Jonsson, K.Nielsen, P. Durkee, R. Flagan, J. Seinfeld, T. S. Bates, and P. K. Quinn, “Clear column closure studies ofurban-marine and mineral-dust aerosols using aircraft, ship, and satellite measurements in ACE-2.” J. AerosolSci. 29(Suppl 1): S1143-S1144, 1998.

Russell, P. B., P. V. Hobbs, and L. L. Stowe, Aerosol properties and radiative effects in the United States eastcoast haze plume: An overview of the Tropospheric Aerosol Radiative Forcing Observational Experiment(TARFOX), J. Geophys. Res., 104, 2213-2222, 1999.

Russell, P. B., J. M. Livingston, P. Hignett, S. Kinne, J. Wong, A. Chien, R. Bergstrom, P. Durkee, and P. V.Hobbs, Aerosol-induced radiative flux changes off the United States mid-Atlantic coast: Comparison of valuescalculated from sunphotometer and in situ data with those measured by airborne pyranometer, J. Geophys.Res., 104, 2289-2307, 1999.

Schmid, B., J. M. Livingston, P. B. Russell, P. A. Durkee, H. Jonsson, K. E. Nielsen, S. Gasso, E. J. Welton, K.Voss, P. Formenti, and M. O. Andreae, “Three dimensional investigation of lower tropospheric aerosol andwater vapor during ACE-2 by means of airborne sunphotometry.” J. Aerosol Sci. 29(Suppl 1): S1145-

Schmid, B., J. J. Michalsky, R. N. Halthore, M. C. Beauharnois, L. C. Harrison, J. M. Livingston, and P. B.Russell, Comparison of aerosol optical depth from four solar radiometers during the Fall 1997 ARM IntensiveObservation Period, Geophys. Res. Lett., 27, 2725-2728, 1999.

Schmid, B., Livingston, J. M., Russell, P. B., Durkee, P. A., Collins, D. R., Flagan, R. C., Seinfeld, J. H., Gasso, S.,Hegg, D. A., Ostrom, E., Noone, K. J., Welton, E. J., Voss, K., Gordon, H. R., Formenti, P., and Andreae, M.O.. Clear sky closure studies of lower tropospheric aerosol and water vapor during ACE-2 using airbornesunphotometer, airborne in-situ, space-borne, and ground-based measurements. Tellus in press, 2000.

Tanré, D., L. A. Remer, Y. J. Kaufman, S. Mattoo, P. V. Hobbs, J. M. Livingston, P. B. Russell, and A. Smirnov,Retrieval of aerosol optical thickness and size distribution over ocean from the MODIS Airborne Simulatorduring TARFOX, J. Geophys. Res., 104, 2261-2278, 1999.

Veefkind, J. P., G. de Leeuw, P. A. Durkee, P. B. Russell, P. V. Hobbs, and J. M. Livingston, Aerosol opticaldepth retrieval using ATSR-2 and AVHRR data during TARFOX, J. Geophys. Res., 104, 2253-2260, 1999.

Welton, E.J., K.J. Voss, H.R. Gordon, H. Maring, A. Smirnov, B. Holben, B. Schmid, J.M. Livingston, P.B.Russell, P.A. Durkee, P. Formenti, M.O. Andrea, and O. Dobovik, Ground-based lidar measurements ofaerosols during ACE-2: Instrument description, results, and comparisons with other ground based and airbornemeasurements, Tellus, in press, 2000.


Investigation Title: Airborne Sunphotometry and Integrated Analyses of Dust, OtherAerosols, and Water Vapor in the Puerto Rico Dust Experiment(PRIDE)

PrincipalInvestigator andteam

PI: Philip B. Russell

Co-Is:Beat SchmidJens RedemannJohn M. LivingstonPeter Pilewskie

Philip B. RussellAtmospheric Chemistry and Dynamics BranchNASA Ames Research CenterMS 245-5Moffett Field, CA [email protected]: 650-604-5404. Fax: 650-604-6779

Beat Schmid, Bay Area Environmental Research Institute, 650-604-5933Jens Redemann, Bay Area Environmental Research Institute, 650-604-6259John M. Livingston, SRI International, 650-859-4174Peter Pilewskie, NASA Ames Research Center, 650-604-0746

Investigation objectives:(1) Improve understanding of dust, other aerosol, and water vapor effects on radiative

transfer, radiation budgets and climate in the Caribbean region(2) Test and improve the ability of satellite remote sensors (such as MODIS, MISR,

CERES, TOMS, AVHRR) to measure these constituents and their radiative effects.

Tasks:(a) Integrate an Ames Airborne Tracking Sunphotometer on a PRIDE aircraft (e.g.,AATS-6 on the SPAWAR Navajo, or AATS-14 on the CIRPAS Twin Otter). (b) CalibrateAATS before and after PRIDE. (c) Provide continuous realtime measurements ofaerosol and thin cloud optical depth spectra and water vapor column contents duringPRIDE flights. (d) Use these data in flight direction and planning. (e) Compare resultsto those of the satellite sensors listed above; in cases of disagreement, investigatecauses and retrieval algorithm improvements. (f) For aircraft profiles derive profiles ofaerosol extinction spectra and water vapor density. (g) Combine these data with thosefrom the Pilewskie SSFR and conduct new analyses of aerosol radiative forcingsensitivity, single scattering albedo, and the solar spectral radiative energy budget. (h)Derive aerosol size distributions from optical depth and extinction spectra. (i) Combinedata with in situ measurements of chemical composition, size distribution, hygroscopicgrowth, and single-scattering albedo to provide tests of closure and integratedassessments of aerosol and trace gas radiative effects.Outputs (what and when):- Aerosol and thin cloud optical depth spectra (380 to 1020 or 1558 nm) and water vapor column contents, in

real time color displays. Produced continuously throughout A/C flight when sunphotometerÕs view of sun is notblocked by thick clouds (τ>~3) or A/C obstructions (e.g., tail, antennas).

- For A/C profiles, haze extinction spectra profiles (380 to 1020 or 1558 nm) and water vapor concentrationprofiles. Produced after flight from smoothed profiles of data resulting from #1. Requires reasonablehorizontal/temporal homogeneity.

Integrated analyses (see above) and publications produced several months to years after measurements,depending in part on availability of othersÕ data and analyses, plus funding levels.

Activity timetable:2000: Jan-Feb: Funding Decision Feb-Apr: A/C Integration Planning, Fit Checks May: Pre-Campaign Sunphotometer Aerosol/Water Vapor Calibration, Mauna Loa Observatory 1-21 Jun: A/C Integration and Test Flights26 Jun-21 Jul: PRIDE Deployment, Roosevelt Roads, PRAug-Oct: Post-Campaign Sunphotometer Aerosol/ Water Vapor Calibration, Mauna Loa Observatory

what we want to do how we plan to do it - nasa...pride_airbornesunphotvgs.doc 8 p. russell, 7/11/00...

Documents