Holistic Interactions of Shallow Clouds, Aerosols, and Land-

Ecosystem (HI-SCALE) Campaign

Phase 1: April 24 – May 20

Phase 2: Aug 28 – Sept 23

ARM Facilities

Oklahoma City

TulsaARM LASSO domain ~33 km wide

G-1 flight paths

Bartlesville

moreless biogenic emissions

meteorology

HR-ToF-AMS (aerosol composition)

CIMS (volatile organic compounds)

miniSPLAT (single particle characterization)

FIMS (aerosol size distribution, 10 – 400 nm)

radiation

cloud properties

aerosol number and size distribution (2 CPC, UHSAS, PCASP, CAS)

CCN (cloud condensation nuclei)

NO, NO2, SO2, CO, O3

CVI inlet for analysis of

cloud droplet residuals

fast-response temperature and humidity

Phase 2 Only: TDCIMS (nanoparticle composition)

Cluster CIMS (inorganic and organic acids and HOMS),

Amine CIMS, Amp-MS

SGP Guest Instrument Facility

PTR-MS

HR-ToF-AMS

SPLAT II

SMPS

nano-SMPS

Aerosol Variations during Phase 1

OM

SO4

NO3

NH4

OM

SO4

NO3

NH4

N NNS NSSNS WEW EES

circles = G-1 values over SGP site and < 1 km AGL

rain

rain

rainrain

rain

rain

rain

0.2% SS

0.4% SS

0.8% SS

winds

east

south

north

west

April Maydate

NPF NPF NPF NPF NPF NPF NPF NPF

OM somewhat correlated with CO

Organics are the dominate component, but there are periods where inorganics

are 50% of total mass

CCN is somewhat correlated with aerosol mass as expected, but need to

account for changes in size distribution and hygroscopicity.

New Particle Formation

September 11

September 17

10 15 20 UTC

10 15 20 UTC

1511-1814 UTC

1638-2009 UTC

Central Facility

Central Facility

100

10

Dia

me

ter

(nm

)

100

10

Dia

me

ter

(nm

)

particle # (cm-3) from CPC 3025

particle # (cm-3) from CPC 3025

southerly winds

variable winds

low high

particle from CPC 3025

Aerosol Science That Can Be Addressed

New Particle Formation and Growth: Does NPF occur at the surface or aloft? What are the mechanisms driving NPF? What processes are controlling the growth of nanoparticles to sizes relevant to CCN and optical properties?

Secondary Organic Aerosol: What are the chemical mechanisms responsible for biogenic SOA? How does anthropogenic sources alter biogenic SOA? How do clouds affect organic aerosols via aqueous chemistry?

Model Evaluation and Improvement: How well do state-of-the-science models represent NPF, SOA, and particle growth in the vicinity of the SGP site? What are the effects of photochemistry, vertical mixing, and long-range transport?

SOA Parcels Experience Rapid changes in RH and TSOA Parcels Experience Rapid changes in RH and T

he

igh

t (k

m)

LES vertical motions in boundary layerwest east SOA

fast ?

slow