CEAZA Jul 2006 Aerosol-cloud interactions offshore Central and Northern Chile Laura Gallardo Klenner Centro de Modelamiento Matemático, Universidad de Chile

CEAZA Jul 2006 Outline VOCALS REx: a few highlights Anthropogenic S perturbation of Sc? –Emissions –Coastal lows –Simulations –Observations Summary and next steps “Camanchaca”

CEAZA Jul 2006 B iotic and A biotic S ulfur I mpacts on S tratocumulus (BASIS) Nov 2002 To take over the world!...PERSIS- TENCE

CEAZA Jul 2006 MechosoBretherton Huebert Weller Wood SOLAS/IGAC?

CEAZA Jul 2006 SST CC% CF Why focusing over the South East Pacific (SEP)?  Subtropical high (subsidence)  Andes Cordillera induces LLJ  Upwelling cold water and nutrients (fishery)  CCN production  Persistent Sc  Effective cooling  Important for regional and global climate  …but models don’t get the Sc right   +Substantial anthropogenic perturbations

CEAZA Jul 2006 CGCM Problems There is a meridional shift in ITCZ a warm SST bias and insufficient stratocumulus cloud cover Mechoso, 2006 CFS Errors SST Prec CLD

CEAZA Jul 2006 South Eastern Pacific/Western South America…WOW!!! 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)

CEAZA Jul 2006 Garreaud, 2006 DMS, sea salt

CEAZA Jul 2006 Pockets of open cells (POCs) e.g., WOW

CEAZA Jul 2006 In the remote marine atmosphere the supply of DMS and its oxidation mechanisms limit the rates of new particle nucleation and growth. These processes probably control the re-filling of POCs with clouds. Iodine, ammonia, and organics may also play a role. Huebert, 2006 e.g., WOW

CEAZA Jul 2006 Weller, 2006 Surface forcing from buoy driving a one-dimensional ocean model (PWP) produces a surface layer that is too warm and too salty. Additional cooling and freshening is needed…..Eddies? ) e.g., WOW

CEAZA Jul 2006 Wood, 2006

CEAZA Jul 2006 NB. Optimi $ m NASA/NOAA/NSF proposals under review Chilean projects (FONDECYT?, Millenium?) 1 month intensive campaign in October

CEAZA Jul 2006 Swedish connection…CCN characterization  ~ 250 kUSD Chilean Air Force

CEAZA Jul 2006 IMARPE fishery research cruise: Oct-Nov 2007 Study region Main goals (main instruments): 1.Characterize the near-coastal 3D wind structure (ship-borne wind profiling radar). 2.Assess the relation between the wind and mesoscale ocean processes (upwelling and eddies) (wind profiler, CTDs and ADCP) 3.Determine the dynamical and thermodynamical structure associated with the coastal clearing (ship-borne radiosoundings). Field experiment: October-November 2007 Cost ~ $70K (Peru) International Partners - Peru

CEAZA Jul 2006 Chile is world’s largest Cu producer … Peru is also a Cu producer Lefhon et al, 1999 CONAMA, 2001

CEAZA Jul 2006 Could the man made S emissions affect the cloud radiative properties? Under which conditions are anthropogenic emissions transported offshore?

CEAZA Jul 2006 MODIS-Cloud droplet number concentration Wood 2005

CEAZA Jul 2006 Garreaud et al, 2002 COASTAL LOWS once a week

CEAZA Jul 2006 Coupled circulations/summer Mechoso, 2006

CEAZA Jul 2006 Cerro Moreno Chuquicamata Strong easterly wind events downwind from the largest smelter…CL like? Huneeus, 2003 Evalution of Antofagasta soundings Focus on extreme events: v 700hPa >5 m/s 82 events Composite CL like

CEAZA Jul 2006 S-SO 2 S-SO 4 Emissions (95%) Emissions (5%) Dry deposition Dry / wet deposition OH Swedish MATCH+HIRLAM fields (ca. 0.1°) Dynamical Interpolation

CEAZA Jul 2006 Model Outputs

CEAZA Jul 2006 We should expect changes in cloud droplet radii …CDNC.. …or???? Average Jul20-Aug20 Event July 26

CEAZA Jul 2006 Observations? Average Jul20-Aug20 July 26 Suggestive, isn’t it?

CEAZA Jul 2006 Furthermore…one can relate CDNC and (sulfate)aerosols Penner et al, 2001 Thanks to an anonymous reviewer!

CEAZA Jul 2006 Connecting CDNC and sulfate mass (Leaitch et al, 1992) More than suggestive, uh?

CEAZA Jul 2006 …But still non-conclusive What about –DMS? –Sea-salt –Other aerosols Are CLs the only relevant weather conditions? Shouldn´t one see a trend change since the 90’s? What are the expected changes in terms of W/m 2 ?

CEAZA Jul 2006 Aerosol characterizations DMS fluxes and evolution Radiative measurements Aerosol-cloud-interactions

CEAZA Jul 2006 FONDECYT Ana María Córdova (CEAZA) Manuel Leiva (CENMA) Laura Gallardo (CMM) …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… –Intensive campaign (2008): activated aerosols at a camanchaca station (CVI+on-line analysis) PM10/PM2.5 at the same site & PIXE analyses & ionchromatograph SO 2 continuosly Sunphotometer(s) –Deploy passive samplers for N-S transect and seasonal changes..changes in reff, CDNC… –Regional climate model simulations –Trend analyses for satellite data

CEAZA Jul 2006 Millennium Science Nucleus on Coastal Climate Dynamics ( ) ? Understanding of the dynamics of the coastal low- level jet system and its relationship with low-cloud cover variability and coastal upwelling Assessing the relative contributions of local and remote forcings in the effectiveness (nutrient availability) of upwelling in north-central Chile Increasing our understanding of how anthropogenic and natural aerosols, mainly sulfate aerosols, interact with the persistent stratocumulus deck in the coastal areas of Central and Northern Chile. Define adequate assimilation strategies for improving radiative transfer simulations in regional atmospheric models

CEAZA Jul 2006 Summary The SEP region is a fantastic research area!!..with a large potential for scientific growth VOCALS offers a unique opportunity to improve our (quantitative) understanding of aerosol-cloud-climate and land-sea-atmosphere interactions There is “evidence” of an impact of anthropogenic sulfate aerosols on the subtropical Sc deck (Huneeus et al, 2006) CEAZA can play a central role…hydrological cycle! Laguna Chaxa, Atacama, Chile