1. Group proposal Aerosol, Cloud, and Climate ( EAS 8802) April 24 th, 2006 Does Asian dust play a role as CCN? Gill-Ran Jeong, Lance Giles, Matthew Widlansky O 3, S O 2, NO 2, HNO 3

2. 1. Motivation: Introduction of a problem Japan spring 2004 (Matsumoto et al., GRL 2006) ACE-Asia spring 2001 (Clarke et al., JGR 2004) Controlling factors to CCN 1.Size 2.Composition (Hygroscopic property) The microphysical and chemical properties of aged mineral dust as a candidate of CCN  sulfate coating in the dust fine mode can become a CCN Tailland, spring 1998 (Rosenfeld et al., PNAS 2001) 1: dust-laden cloud 2: dust-free cloud 3:smoke in dust

3. 1. Motivation: Importance of complexity The limitation of current understanding Lack of long term dust record downwind of Asian outflow. Ability to discriminate clouds from dust in current satellite images. Measurements of CCN during dust and non-dust periods. 1. Why do we need to do another field experiment in East Asia region? New A-train land-ocean satellite coverage (launched yesterday) i) Overcoming of cloud contamination in dust detection ii) Three dimensional measurement of cloud structure In addition, aircraft and ground-base measurement The temporal and spatial resolution of instrumental measurement and are they consistent? 2. What do we want to see? During dust and non-dust period: i) Vertical profiles of the CCN, clouds, water vapor ii)Time required for a dust CCN to grow into cloud droplets. iii) Size resolved chemical composition

4. 2. Objectives and goals 2. Investigate satellite observations pertaining to dust, clouds and precipitation with the same temporal and spatial resolution. (Cloudsat, MODIS and CALIPSO) 3.Investigate data from airborne and ground-base measurements of dust size distribution, chemical composition, and pH of precipitation. 4. Compare individual instrumental measurements to map 3-D dust and precipitable water distributions. 1.Analyze the previous data on dust, clouds, and precipitation in order to find any relation between dust. clouds and precipitation. Goals 1.Find what roles Asian dust play as CCN? 2.Investigate effects of mineral dust on the aerosol-cloud-climate system.

5. Data analysis Visibility, cloud and precipitation from surface meteorological data, ISCCP, GPCP Cloud and CCN PrecipitationDust (satellite) Dust (ground-base) 3-D Cloud, CCN distribution 3-D Dust distribution Dust size radius Fraction of chemical composition Dust – Cloud – Climate A suit of Measurement Validation of observation Expected results Proof of dust-induced CCN 3. Strategy Preliminary study Contribution to understanding Climate system Time series Space120 º E ~ 150ºE, 20ºN ~ 40ºN TimeSpring, 2007 (March, April)

6. 4. Experimental instruments Measured Quantity Dust size distributionOPC IMPACTOR electron and optical microscopy Dust chemical compositionsAerosol mass spectrometer Instrument Cloud profile Liquid and ice contentsCloudSat Rain drop and precipitation Aerosol profileCALIPSO(CALIOP) Cloud profile Optical depth of thin cirrus cloud Aerosol optical depthMODIS Particle size TOA radiation budgetCERES Past long-term dust concentrationSurface observation of visibility monthly mean precipitationGPCP 3-hour average cloudISCCP

7. MODISCloudSatCALIPSO 4. Experimental Instruments - Variable resolutions range: - Swath width of 2330km 250m (bands 1-2) 500m (bands 3-7) 1000m (bands 8-36) - Cloud and Aerosol products by MODIS: Cloud and aerosol optical depths Particle size information Cloud-top height Cloud emissivity Sample of Aerosol Optical Depth Measurements: - 94-GHz nadir-looking radar measures backscatter - Measure profiles of cloud optical properties - Measure cloud liquid and ice water content - Profile the vertical structure of clouds (500m vertical resolution) - Will distinguish between cloud condensate (cloud particles) and precipitation - Polarization-sensitive lidar - Active lidar instrument (CALIOP) with passive infrared (IIR) and visible imagers (WFC) to probe the vertical structure and properties of thin clouds - Measures the 1064nm backscatter intensity and the polarized 532nm backscattered signal

8. 5. A contribution to understanding aerosol-cloud-climate Direct impactIndirect impact Radiativeradiative forcing at TOA radiative forcing at the sfc heating/cooling actinic flux Chemical heterogeneous chemistry on dust surface photolysis negative positive or negative (?) Asian dustCloud and precipitation Hydrological cycle in Asian region (negative or positive feedback) Asian dust may suppress or enhance precipitation outflow of Asian dust region. Dust properties

9. 5. A contribution to understanding aerosol-cloud-climate Direct impactIndirect impact Radiativeradiative forcing at TOA radiative forcing at the sfc heating/cooling actinic flux cloud properties Chemical heterogeneous chemistry on dust surface photolysis Hygroscopic CCN negative positive or negative (?) Asian dustCloud and precipitation Hydrological cycle in Asian region (negative or positive feedback) Asian dust may suppress or enhance precipitation outflow of Asian dust region. Dust properties

10. 5. A contribution to understanding aerosol-cloud-climate