Summary ofARCTAS P-3 Data Flight #21

Flown 7 Jul 2008

Phil Russell, NASA Ameswith contributions from many, many

experimenters, modelers, forecasters, & P-3 air & flight crews

Postbrief/Science Meeting

3:00 Tue 8 Jul 2008

AOD, 0Z,7/8

STEM Model prediction (U Iowa): July 7 P3 Flight

GEOS5 Forecast: July 7 P3 Flight

Lots of aerosols in the Siberian fire/Asian anthro. Plume, including sulfate, dust, OC, & BC.

GEOS5 Forecast: July 7 P3 Flight

No significant California fire or N. American pollution.

A strong Siberia fire/Asian anthropogenic plume between 7-10 km.Weak Siberia fire/Asian anthropogenic plumes between 1-6 km.

P-3 in ARCTAS: PayloadAmes Airborne Tracking

Sunphotometer (AATS-14)

Solar Spectral Flux Radiometer (SSFR)

Broad-Band Radiometers (BBR)

LW SW

HiGEAR Aerosols & O3

OPC & DMA dry size dist, volatility Tandem Volatility DMA Neph scat + PSAP abs Humidified Neph f(RH) Ultrafine & CN Time of Flight Mass Spec size resolved chemistry SP2 black carbon mass

AERO3X Cloud Absorption Radiometer (CAR)

P-3 Data System (PDS): Nav, Flight, Met (P, T, RH, …) REVEAL & RTMM

AOD Ext H2O vapor

Cavity Ringdown ext (2) Reciprocal Neph sca (2, RH ) Radiance, BRDF

Flux↑,↓(), albedo()

Flux↑,↓, albedo

Nenes CCN PVM cloud drop reff, vol

TECO O3

COBALT: CO

AOD, 0Z,7/8P3 Plan A Mon 7 Jul

Goals:1.Asian-Siberian plume above low cloud in A-Train footprints (in situ aer, CO, O3, rad gradient & stack, CAR cloud BRDF, CALIPSO val, aer effects on MODIS PM cloud retrievals)2.Ice Field BRDF3.Clear-sky work at WP 6 as fallback.

P3 Plan B Mon 7 Jul

Goals:1.Asian-Siberian plume above Saturn Island AERONET (in situ aer, CO, O3 -AATS spiral, rad gradient & stack, CAR-AERONET)2.Ice Field BRDF3.Clear-sky work at WP 6 as fallback.

AOD = 0.49 on 6 Jul

AOD, 0Z,7/8

GEOS5 Forecast: July 7 P3 Flight - Clouds

Some middle and high clouds near Cold Lake.Close to Vancouver and Victoria island, some low clouds but no middle/high clouds.

AOD, 0Z,7/8

AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:1.Aerosol radiative forcing efficiency (F/AOT) under edge of advancing Asian/Siberian plume2.Aerosol effects on MODIS-Terra cloud remote sensing3.Tests of model aerosol, CO, & O3 predictions @ many locations4.Radiant flux divergence stacks for SSA() @ 2 locations5.CAR circles over AERONET for CAR-AERONET retrievals6.3-way closure (in situ, AATS, AERONET) in spiral

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04/21/2304/21/23 01:38 PM01:38 PM J. Redemann, P. Pilewskie, P. Russell. NASA Ames & U. ColoradoJ. Redemann, P. Pilewskie, P. Russell. NASA Ames & U. Colorado1212

Climate Change Science in INTEX-A/ICARTT Climate Change Science in INTEX-A/ICARTT Measurements of Aerosol Effects on the Measurements of Aerosol Effects on the

Solar Energy that Drives ClimateSolar Energy that Drives Climate

So

lar

ener

gy

[W m

So

lar

ener

gy

[W m

-2-2]]

Aerosol Amount, Aerosol Amount, AOD(499 nm)AOD(499 nm)

Jetstream 31 (J31)

Fo

rcin

g E

ffic

ien

cy [

W m

Fo

rcin

g E

ffic

ien

cy [

W m

-2-2]]

CaseCase

Slope =Aerosol Radiative Forcing Efficiency

Case 2,

21 Jul2004

Scientific Conclusions

1.The gradients (spatial variations) in AOD that occur frequently off the US East coast provide a natural laboratory for studying effects of aerosol particles on solar energy, and hence on climate.

2.For the average aerosol optical depth of ~0.5 in the 10 cases shown above, aerosols on average reduced the incident visible radiation (near midday) by the amount of energy it would take to power one 40 W light bulb for every square meter of ocean surface (0.5 x -80 W m-2 = -40 W m-2; see right frame above).

Redemann et al., Redemann et al., JGRJGR, 2006, 2006

Boreal Forest Fire Boreal Forest Fire Smoke Early in Smoke Early in INTEX-AINTEX-A

AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:1.Aerosol radiative forcing efficiency (F/AOT) under edge of advancing Asian/Siberian plume2.Aerosol effects on MODIS-Terra cloud remote sensing3.Tests of model aerosol, CO, & O3 predictions @ many locations4.Radiant flux divergence stacks for SSA() @ 2 locations5.CAR circles over AERONET for CAR-AERONET retrievals6.3-way closure (in situ, AATS, AERONET) in spiral

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S. Howell et al., HiGEAR

PRELIMINARY

AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:4. Radiant flux divergence stacks for SSA() @ 2 locations5. CAR circles over AERONET for CAR-AERONET retrievals6. 3-way closure (in situ, AATS, AERONET) in spiral

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Downwelling Flux: F

Upwelling Flux: F

Net Flux: F- F

Flux Divergence (absorption):

(F- F)2000m- (F- F)43m

Fractional absorption:

[(F- F)2000m- (F- F)43m]/ F2000m

2000 m

43 m

Background on Radiative Flux Divergence & Closure, Absorption Spectra, etc.

P. Russell, DOE-ASP Meeting, Annapolis, MD, 27 Feb 2008P. Russell, DOE-ASP Meeting, Annapolis, MD, 27 Feb 2008

P. Russell, Earth Science Seminar, NASA Ames, 19 July 2007P. Russell, Earth Science Seminar, NASA Ames, 19 July 2007

Aerosol Aerosol AbsorptionAbsorption Optical Depth (AAOD) Spectra Optical Depth (AAOD) Spectra from 5 Experimentsfrom 5 Experiments

Wavelength, nm

Ab

so

rpti

on

Op

tica

l Dep

th

Bergstrom et al., ACP, 2007

AAOD = AAOD = K K -AAE-AAE

Absorption Absorption Angstrom Angstrom Exponent (AAE)Exponent (AAE)

AAE =AAE = 1.451.45

2.272.27

2.342.34

1.051.05

1.121.12

For Black For Black Carbon, AAE = 1Carbon, AAE = 1

AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:4. Radiant flux divergence stacks for SSA() @ 2 locations5. CAR circles over AERONET for CAR-AERONET retrievals6. 3-way closure (in situ, AATS, AERONET) in spiral

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AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:4. Radiant flux divergence stacks for SSA() @ 2 locations5. CAR circles over AERONET for CAR-AERONET retrievals6. 3-way closure (in situ, AATS, AERONET) in spiral

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The first half of the flight encountered a well-mixed local pollution layer up to ~2 km GPS altitude and a long-range transport air mass above, both homogenous over >200 km.

Julia

n D

ay U

TC

220

km

PRELIMINARY DATAfrom AATS & HiGEAR groups

AOD at 550 nm between 500 – 6250 m GPS alt : 0.201

PRELIMINARY DATAfrom HiGEAR group

Clarke, McNaughton, Howell, Freitag et al.

Missing layers at the top and bottom estimated by extrapolation, as illustrated in subsequent slides.

PRELIMINARYData from AATS, AERONET, & HiGEAR groups:

Redemann, Shinozuka, Livingston, Ramachandran et al.McArthur et al.

Clarke, McNaughton, Howell, Freitag et al.

Analysis by Yohei Shinozuka

RH, 0Z,7/8 at 5.5 km

RH, 0Z,7/8 at 1.5 km

RH, 0Z,7/8 at 8.5 km

Siberia biomass burning plume between 1-6 km + weak Asian anthropogenic pollution.

GEOS5 Forecast 20080707_06Z: July 7 P3 Flight

AOD, 0Z,7/8

AOD, 0Z,7/8

AOD, 0Z,7/8

AOD, 0Z,7/8

AOD, 0Z,7/8

P3 For July 7, 2007

Anthro lower

AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:4. Radiant flux divergence stacks for SSA() @ 2 locations5. CAR circles over AERONET for CAR-AERONET retrievals6. 3-way closure (in situ, AATS, AERONET) in spiral

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AOD, 0Z,7/8P3 Actual Mon 7 Jul

Accomplishments:4. Radiant flux divergence stacks for SSA() @ 2 locations5. CAR circles over AERONET for CAR-AERONET retrievals6. 3-way closure (in situ, AATS, AERONET) in spiral

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