Monitoring trace gas
emissions and transport with
Aura and the A-Train

Simon Carn
Dept. of Geological and Mining Engineering, Michigan Technological
University, Houghton, MIAura (2004-)

CloudSat (2006-)

OMI - SO2, NO2, BrO

Aqua (2002-)

CPR (radar) –precipitation,hydrometeors

MODIS - SO2, ash, sulfate

TES - SO2
MLS - strat. SO2, HCl

AIRS - UTLS SO2, ash

Dec 2014?

The A-Train
CALIPSO (2006-)
CALIOP (lidar) - cloud altitude, aerosol phaseAura - Ozone Monitoring Instrument (OMI)• UV/Visible sensor• On NASA/Aura satellite• Launched July 2004
• Daily contiguous global
coverage (until 2008)• 13 x 24 km nadir pixel• Overpass at 1:30-2:00 pm localtime• Measures SO2 total column(plus other gases and aerosols)• Data publicly available and free
• NRT SO2 data available on web

Passive degassingin the SW Pacific

1 Dobson Unit (DU) = 0.03 g m-2 SO2• First satellite sensor to provide daily, global SO2 measurements withsensitivity to the lower troposphere (i.e., passive volcanic degassing)Global sulfur emissions inventory
Volcanic

Explosive (E)Passive (P)• Climate impact of volcanic sulfate aerosol• Global fluxes of other volatile species• Altitude of emissions critical[Graf et al., 1997; Andres & Kasgnoc, 1998; Smith et al., 2011]

OMI annual average SO2 in 2005: W. Pacific/S.E. Asia
China
AnatahanManamBagana

AmbrymOMI annual average SO2 in 2006: W. Pacific/S.E. Asia
China
AnatahanRabaulJavaBagana

AmbrymGlobal SO2 emission source catalog (Fioletov et al., in prep)
Example: Volcanoes in Japan (multi-year OMI SO2 averages)

Asama

Suwanose-jima

Satsuma-iwojima

Sakura-jima

AsoMiyake-jimaComparing emission inventories with measurements• OMI measurements indicate
deficiencies in current volcanic
SO2 emission inventories

REMOTE model simulation of annual
mean SO2 columns over Indonesia[Pfeffer et al., ACP, 2006]

Trends in NO2 emissions in East Asia (Lok Lamsal, NASA)

Annual averages of OMI tropospheric NO2 columns

Combine OMI SO2 and AIRS CO to Identify Transpacific
Transport Events: One Example in 2006

[Hsu et al.,JGR 2012]

Oct. 8Oct. 9Oct. 10Oct. 11Oct. 12OMI
SO2(DU)
TrajectorySO2 plumeHeight (3 km)
AIRS CO(1018mole/cm3)
Using CALIPSO, the Plume Height can be verified along the transport pathway.

Relative sensitivity of UV and IR measurements
ZUV~Tropopause
IR (ν3, 7.3 µm)~4 km
Sensitivity
Courtesy of L. Clarisse, ULB

Prata and Bernardo, 2007

• IR channels at ~4 µm and ~8.6 µm can detect lower tropospheric SO2

Aura/OMI - Aqua/AIRS: Sierra Negra (Galapagos) 2005
AIRS 19:55 UTOMI 20:10 UT

S. NegraS. Negra

Lower tropospheric SO2F. Prata, NILU

• Sierra Negra (Galapagos) eruption, October 24, 2005
• OMI-AIRS synergy indicates SO2 concentrated in the lower troposphere• Altitude determines climate impact of SO2 and sulfate aerosolSarychev Peak (Kurile Is) eruption, 11-16 June 2009

Fill withSO2gap
dataOMI
rowAqua/AIRS
anomaly: data
Astronaut photo from ISS, 14 June

• 11-16 June 2009
• 2nd large NH stratosphericSO2 injection (≥1 Tg) in a year,
after the August 2008
Kasatochi eruption (Aleutian Is)• Timing near summer solsticeincreases aerosol radiative(cooling) effect• Major disruption to aviation• Current OMI row anomaly creates data gaps in large volcanic eruption clouds• A-Train synergy compensates for lost data and improves SO2 loading measurements

Aviation hazards from volcanic eruption clouds
Eyjafjallajökull (Iceland) 2010•

Immediate hazards•

Secondary hazards•

Mitigation– Engine failure due to melted ash– Abrasion of windshield– Corrosion by ash, sulfuric acid

– Immediate detection of fresh volcanic clouds– Tracking/forecast of cloud position and altitude –SO2 valuable for cloud tracking

A-Train measurements of volcanic ash concentrations• Ash concentration =mass loading/thickness• Thickness from CALIOP
Eyjafjallajökull (Iceland)
May 8, 2010

• Typical concentrations
were ~2-4 mg m-3

Fine volcanic ash

MLS SO2 band

Ash aggregates,hydrometeors

A-Train sensor synergy in volcanic clouds

W-band (~3 mm) radarHydrometeor-enhanced sedimentation of volcanic ash

Sassen et al. [2007]

200 microns• Ash aggregation prematurely removes fine ash that would be an aviation hazard• How do we explain secondary ash thickness maxima and ash aggregate fallout?
• Can CloudSat W-band radar detect the bright band?
[Durant et al., JGR, 2009]

A-Train observations: Chaitén (Chile) eruption (May 7, 2008)

AIRS BTDEyjafjallajökull eruption plume (April 15, 2010) – Aqua/MODIS

Extent of ash plumeAqua/MODIS ash retrievals (M. Pavolonis, NOAA/NESDIS)CALIPSO: April 15, 2010

CirrusWinker et al., JGR [2012]-> Ash at 1-3 km altitude
Marine stratocumulus

CALIPSO + CloudSat: April 15, 2010

Cirrus‘Altostratus (As)’Winker et al., JGR [2012]-> Ash at 1-3 km altitude
Marine stratocumulus

CALIPSO + CloudSat + OMI: April 15, 2010

Summary• Aura/OMI measurements of trace gases (SO2, NO2) are improving
volcanic and anthropogenic emissions inventories• A-Train synergy is providing unprecedented observations of the vertical
distribution of trace gases, aerosols and hydrometeors in volcanic
clouds and pollution outflow• Measurements of ash cloud altitude and thickness (e.g., by CALIPSO)
are of prime importance for aviation hazard mitigation• Data latency of most A-Train products (and spatial coverage of theactive sensors) is the main impediment to operational use for aviation
hazard mitigation and other applications• The A-Train greatly facilitates validation/intercomparison of satellite data
products (e.g., SO2 column measurements)
Acknowledgments:

Ozone Monitoring Instrument (OMI) row anomaly
Jun 25, 2007

May 11, 2008
CALIPSO/CloudSat track
Jan 24, 2009http://www.knmi.nl/omi/research/product/rowanomaly-background.php

Eyjafjallajökull eruption plume – April 15, 2010OMI SO2 column

OMI Aerosol Index• NB: OMI row anomaly coincides with CALIPSO/CloudSat trackRelative humidity wrt ice (RHice) from Aura/MLS

MLS RHice is derived from Temperature and H2O data and the Goff-Gratch equation

Conditions for ice nucleation
MLS RHI profiles

Steinke et al., ACP, 2011
Deposition nucleation• Conditions in CPR feature:• T = ~210-260 K• RHice = 150-160% at 316 hPa(~8-9 km altitude)

Atmospheric Physics Lab, ETH, Zurich

Redoubt volcanic cloud ~5 hours after eruption (CALIOP)

March 26, 2009, 22:45 UTC

Redoubt volcanic cloud ~5 hours after eruption (CALIOP+CPR)

March 26, 2009, 22:45 UTCCALIPSO first light – Soufriere Hills volcanic cloudSulfate aerosol layer

OMI SO2 – 7 June 2006

OMI SO2 - 7 June 2006

CALIPSO ‘first light’ - 7 June 2006