Airborne sunphotometer (AATS-14) measurements in ARCTAS - first insights into their combined use with satellite observations to study Arctic aerosol radiative effectsJ. Redemann1, J. Livingston2, Y. Shinozuka3, P. Russell3, Q. Zhang1, R. Johnson3, S. Ramachandran3,4, A. Clarke5, C. McNaughton5, B. Veheilmann61Bay Area Environmental Research Institute, Sonoma, CA, 2SRI International, Menlo Park, CA, 3NASA Ames Research Center, Moffett Field, CA, 4Physical Research Laboratory, Ahmedabad, INDIA, 5HiGEAR group, Univ. of Hawaii, HI, 6Royal Netherlands Meteorological Institute (KNMI), DeBilt, The Netherlandshttp://geo.arc.nasa.gov/AATS-website/email: Jens.Redemann-1@nasa.gov

2007 LMU, Redemann

1.Measures direct solar beam transmission: 353.5 380.0 449.0 499.4 525.0 605.7 675.1 778.4 864.5 939.7 1019.1 1241.3 1557.8 2139.0 nm

Yields:aerosol optical depth & columnar water vapor (ozone under certain conditions)

aerosol extinction & water vapor (ozone) concentration when aircraft flies profiles

Size:Telescope dome 8" OD (hemisphere) atop 5" H pedestal. (Total H: 9" above A/C skin), Inside A/C: 12" D x 18" H cylinder.

Weight:131.6 lbsNASA Ames Airborne Tracking Sunphotometer: AATS-14

2007 LMU, Redemann

AATS-14 operated success-fully on all 24 NASA P-3B flights.AATS-14 collected science data on 20 of those flights (exceptions - two transit, one engineering check flight and one science flight, when environmental conditions were unfavorable).AATS-14 science objectives for ARCTAS: integrated analysis of the horizontal and vertical distribution of Arctic Haze aerosols and the emissions from boreal forest fires, the combination of AATS-derived AOD measurements with solar irradiance measurements on the P-3B to determine aerosol direct radiative effects, the use and validation of aerosol observations from MODIS, MISR, OMI, POLDER and CALIPSO in conjunction with AATS measurements to address ARCTAS science objectives.

2007 LMU, Redemann

2007 LMU, Redemann

Saturn Island off Vancouver

2007 LMU, Redemann

ARCTAS-spring, AATS summary

2007 LMU, Redemann

ARCTAS-summer, AATS summary

2007 LMU, Redemann

ARCTAS Theme 3: Aerosol Radiative Forcing - Two ways to measure direct aerosol radiative effectsFlux divergence method requires flux measurements at two alt. + layer AODAOD&flux gradient method in INTEX-A required:Dcos(q)/Dt1 & Dt499nm>0.05

2007 LMU, Redemann

2007 LMU, Redemann

2007 LMU, Redemann

ARCTAS satellite OP info relative to AATS obs.AATS-14 (+-1 hour of sat. OP time)DateFlight #Flight LocaleAATS data times (UT)SatelliteOP time UTSuccessful satellite AODmin altmax altmin AOD 519 nmmax AOD 519 nm04/19/0810Transit, FAI -> Ames17.84 - 25.40 Terra2030MODIS0.047.410.010.35 Aqua2215MODIS1.016.000.130.2806/24/0812CARB Flight Ames ->Ames16.98 - 24.72??06/26/0813Transit Ames ->Edmonton14.67 - 20.41 Terra1830MODIS0.927.360.010.43 Aqua2010MODIS5.807.350.010.1006/26/0814Transit Edmnt ->Cold LakeTransit06/28/0815Local, Cold LakeTest06/29/0816Local, Cold Lake16.70 - 23.35 Terra1855MODIS & MISR0.756.760.012.24 Aqua2045MODIS0.246.980.010.0306/30/0817Local, Cold Lake18.60 - 23.19 Terra1800MODIS2.503.890.030.13 Aqua1950MODIS & OMI0.414.440.023.8907/02/0818Local, Cold Lake15.10 - 21.69 Terra1750MODIS0.343.250.032.00 Aqua1935MODIS0.673.520.045.2707/03/0819Local, Cold Lake16.35 - 24.92 Terra1830MODIS & MISR0.516.260.030.26 Aqua2020MODIS&OMI0.623.630.090.2607/06/0820Local, Cold Lake17.74 - 24.03 Terra1900MODIS & MISR0.206.150.010.08 Aqua1915MODIS0.006.150.010.14 Aqua20500.002.690.033.5207/07/0821Local, Cold Lake18.68 - 25.62 Terra1810MODIS6.146.210.010.05 Terra1945MODIS5.077.470.010.12 Aqua2130-2135MODIS0.057.490.030.1507/09/0822Local, Cold Lake16.30 - 23.9807/10/0823Local, Cold Lake17.47 - 22.92 Terra1835-1840MODIS & MISR0.905.490.010.06 Aqua2025MODIS0.513.720.025.6207/12/0824Transit, Cold L. ->Wallops14.01 - 16.00

2007 LMU, Redemann

Flight 17, June 30, 2008 - planned

2007 LMU, Redemann

2007 LMU, Redemann

CALIPSO profile, all adjacent pro-files yield no aerosol retrieval

2007 LMU, Redemann

ARCTAS: 30 June 2008

2007 LMU, Redemann

log AOD = a0 + a1*log l + a2*log2lARCTAS: 30 June 2008

2007 LMU, Redemann

P-3B flight track color-coded by AATS AOD (451 nm)ARCTAS: 30 June 2008Note: Google Map from July 1, 1545 UTAATS: 19.65-19.95 UT Aqua: 19.83 UT Aura: 20.01 UT

2007 LMU, Redemann

ARCTAS: 30 June 2008OMI retrievals in highlighted cells likely cloud-contaminated

2007 LMU, Redemann

ARCTAS: 30 June 2008AATS: Squares show mean and vertical bars give range of cloud-free AODs within MODIS grid cell. AOD uncertainties are smaller than the symbols.MODIS: Vertical bars equal expected uncertainty in over-land AOD retrieval.AATS and MODIS AOD Spectra

2007 LMU, Redemann

ARCTAS: 30 June 2008OMAEROOMAERUVAATSMODISMODIS AOD (470 nm)OMIMODIS

2007 LMU, Redemann

(1) In a preliminary analysis of 35 vertical profiles, AATS-14 measurements of layer AOD agree with AOD calculated from HiGEAR in situ observations to within 0.020.1*AOD. Measure-ments of AOD from AATS-14 and AERONET agree well with each other (exc. 1.6 mm) and AOD calculated from HiGEAR in situ observations in three cases studied in detail (Shinozuka).(3) An initial survey of the AATS data set indicates a considerable number of possible case studies for the gradient method of deriving aerosol direct radiative forcing efficiencies and a smaller number of possible cases for studying aerosol flux divergence more cases in ARCTASsummer.(4) AATS data set yields large number of satellite AOD validation opportunities. Preliminary analyses of measurements acquired on June 30, 2008 indicate that the AATS, OMI, CALIPSO and MODIS aerosol retrievals paint a consistent picture of the smoke plume. Spatial averaging is an important issue to consider in reconciling different satellite observations in the immediate vicinity of smoke plumes. Preliminary Findings

2007 LMU, Redemann

*********************