VOCALS lgk Ig'06

Biotic and Abiotic Sulfur

Impacts on Stratocumulus

(BASIS)

VOCALS lgk Ig'06

Outline• Background

• Questions

• Method and tools

• Mean$..so far

• Who …so farCamanchaca

VOCALS lgk Ig'06

South Eastern Pacific/Western South America…• Active volcanoes (natural emissions)

• Atacama: dryest desert of the world between the open Pacific and the heigh Andes (dust and circulations)

• Intensive and long-term mining activities (anthropogenic emissions)

• Humboldt current, upwelling and fishery (biogenic emissions, air-sea exchange and circulations)

• Most persistent and extensive subtropical Sc deck of the SH (microphysics and energy balance)

VOCALS lgk Ig'06

Interestingly/Suspiciously enough…

CDNC

VOCALS plan/Wood et al 2005

VOCALS lgk Ig'06

We know the continental SOx emissions

VOCALS lgk Ig'06

We know the circulation(s)

J J

Rutllant et al 2003; Huneeus, 2003

Antofagasta, sounding station/long recordSounding campaignsSimulations

VOCALS lgk Ig'06

We have identified strong easterly winds events (> 5m/s at 700 hPa), which…

Average July 20-August 20 2000 vs July 26 2000

Huneeus et al, 2006

VOCALS lgk Ig'06

The questions we want to address• Which are the emission strengths and distributions of natural

and anthropogenic emissions of aerosols and precursors over

the area? (Emphasis on sulfur)

• Which is the regional distribution of these (sulfate) aerosols?

Which is the relative contribution of anthropogenic and

natural sources ?

• Which aerosols are present and which become activated (CCN)

in the coastal stratus deck (“camanchaca”)?

• How (much) do the anthropogenic sulfate aerosols affect cloud

properties off the coast from Chile? Has there been a trend in

the CDNC signal?

VOCALS lgk Ig'06

How…• …emission strengths/distribution …

– Anthropogenic and volcanic: compile, order, check, extrapolate…

– Biogenic:…parameterize…ROUGH estimate

• …regional distribution and relative contributions..– Dispersion modeling using re-analysis and downscaling

– Compare with available observations

• …which aerosols become CCN…– Measurement campaign:

• activated aerosols at a camanchaca station (CVI+on-line analysis)

• PM10/PM2.5 at the same site & PIXE analyses & ionchromatograph

• SO2 continuosly

• Sunphotometer(s)

– Deploy passive samplers for N-S transect and seasonal changes

• ..changes in reff, n, CDNC…– Regional climate model simulations– Trend analyses for satellite data

VOCALS lgk Ig'06

VOCALS lgk Ig'06

Mean$...so far• Chilean Research Council/FONDECYT 2007 -

2010 (June 2006)– Logistics and analyses– Students/Research assistants– Publications– Traveling

• Swedish Research Council (April/May 2007)– Visits and training– Logistics (some)

• ECOS Sud collaboration agreement (C03U04)

VOCALS lgk Ig'06

Who so far?Chile• Ana María Córdova (CEAZA)• Laura Gallardo (CMM-U)• Manuel Leiva (CENMA)Sweden• Radovan Krejci (MISU)• Annica Ekman (MISU)

France• Isabelle Chiapello• Jean-Francois Léon (LOA)

VOCALS lgk Ig'06

Open questions

1. Mean$??...Other sources?

2. Other participants and instruments?

3. More explicit combinations/coordinations with VOCALS?, e.g., LLJ study

4. The Chilean Air Force airplane?

Chilean Air Force