SAT280: Remote Sensing of Clouds Professor Menglin Jin, SJSUCloud typesSlide 3Slide 4Slide 5Open cell cloudsWave cloudsCloud ObservationsHistorical Cloud Data sets from SpaceInternational Satellite Sensors for Cloud Detection and Optical PropertiesCloud Products and TechniquesCloud Products and Techniques (continued)MODIS Operational Cloud ProductsMODIS Cloud Mask (MOD35/MYD35)What Does It Mean by a Cloud MaskSlide 16Slide 17MODIS Cloud Mask (S. A. Ackerman, W. P. Menzel – Univ. Wisconsin)Cloud Top PropertiesMODIS Ice Cloud Size Distributions (based on FIRE II IFO, re ~ 7 – 60 µm)MODIS Ice Crystal Library habits/shapesCloud Thermodynamic PhaseDecision Tree for Cloud RetrievalsCloud Mask Tests a Function of EcosystemCloud Mask Tests over an Snow/Ice EcosystemFinal Thermodynamic Phase TestsBispectral Phase TestsTerra/MODIS Cloud Thermodynamic Phase (M. D. King, S. Platnick, J. Riédi et al. – GSFC, U. Lille)Cloud Optical Thickness & Effective Radius (M. D. King, S. Platnick – NASA GSFC)Cloud Optical Thickness and Effective Radius UncertaintyMonthly Mean Cloud Fraction (S. A. Ackerman, R. A. Frey et al. – Univ. Wisconsin)Zonal Mean Cloud Fraction (S. A. Ackerman, R. A. Frey et al. – Univ. Wisconsin)Time Series of Cloud Fraction during the DaytimeMonthly Mean Cloud Top Properties (W. P. Menzel, R. A. Frey et al. – Univ. Wisconsin)Zonal Mean Cloud Top Pressure (W. P. Menzel, R. A. Frey et al. – NOAA, Univ. Wisconsin)Monthly Mean Cloud Fraction by Phase (M. D. King, S. Platnick et al. – NASA GSFC)Monthly Mean Cloud Optical Thickness (M. D. King, S. Platnick et al. – NASA GSFC)Zonal Mean Cloud Optical Thickness (M. D. King, S. Platnick et al. – NASA GSFC)Monthly Mean Cloud Effective Radius (M. D. King, S. Platnick et al. – NASA GSFC)Zonal Mean Cloud Effective Radius (M. D. King, S. Platnick et al. – NASA GSFC)Cloud Optical Thickness Uncertainties (S. Platnick, R. Pincus, M. D. King et al. – GSFC, CDC)Cloud Effective Radius Uncertainties (S. Platnick, R. Pincus, M. D. King et al. – GSFC, CDC)Multilayer Cloud Flag (S. Platnick, M. D. King et al. – NASA GSFC)California / California Current Regime Joint Histograms of Liquid Water Clouds over OceanMODIS Level-3 Monthly Global Browse ImagesSummary and ResourcesSummary and ConclusionsSAT280: Remote Sensing of CloudsProfessor Menglin Jin, SJSUSAT280: Remote Sensing of CloudsProfessor Menglin Jin, SJSUModified from: Michael D. KingOutlinePerspective–Why clouds? What can we infer from satellites?International satellite sensors enabling remote sensing of cloud properties (amount, optical properties, height)–AVHRR, MODIS, MISRPhysical principles behind the remote sensing of cloud properties from satellites, with special emphasis on MODIS–Cloud mask (i.e., what constitutes a cloud?)–Cloud top properties–Cloud optical and microphysical propertiesCloud retrievals from MODIS–What do the data show about cloud properties worldwide?Opportunities for the futureMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20072E O SCloud typesCloud typesCloud typesCloud shield: Broad, circular mass of cloudsCloud Band: 400-200km long, 100-50km wide (4:1 scale)Cloud line–Narrow band of connected cells–Less than 1º latitude in widthMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20073E O SCloud typesCloud typesVortex–Center of rotation–Often associated with upper-level low/vorticity maximum–Mesovortex may be associated with a tropical system or convective complexMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20074E O SCloud typesCloud typesCloud street: A line of unconnected cellsOpen cellular clouds–Hexagonal-shaped rings with cloud-free centers–Usually cumuliform cloudClosed cellular clouds–Hexagonal, closed cloud ring–Usually stratiform cloudMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20075E O SCloud StreetsMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20076E O SOpen cell cloudsOpen cell cloudsMichael D. King, EOS Senior Project Scientist AOSC625 – Spring 20077E O SWave cloudsWave cloudsWill cover with thunderstorms, turbulence and orographic obsrtuctionsare critical–Radiation budget studies (e.g., CERES/MODIS/GEO)–Water budget/cycle studies (e.g., role of ice clouds and convection in upper troposphere humidity)–Data assimilation–Cloud process studies, including aerosol-cloud interactions–Atmospheric chemistry (effect on photochemistry, Liu et al., 2006) Cloud Observations Cloud ObservationsISCCP (International Satellite Cloud Climatology Project)– Routine operation since 1983– Primary data source is worldwide geosynchronous satellites having two bands (visible and 11 µm thermal band)– Clouds are classified by optical thickness and cloud top pressure– Marine stratocumulus clouds vary with roughly the same phase in NH & SH (1-2 month lag)– Cloud optical thickness is higher in NH than SH, and is higher over land than ocean– Effective radius is larger over ocean than land, and larger in SH than NHHIRS (High Resolution Infrared Radiation Sounder)– Routine operation since 1979– Clouds found to be most prevalent in the Intertropical Convergence Zone (ITCZ) of the deep tropics and the middle to high latitude storm belts–CO2 slicing estimates of cloud fraction and cloud top pressure– Decadal average cloud cover has not changed appreciably from the 1980s» High altitude cirrus clouds increased 10% in the 1980s and 1990s over the tropicsHistorical Cloud Data sets from SpaceHistorical Cloud Data sets from SpaceEOS and beyond–Routine determination of cloud top pressure, optical thickness, effective radius, and thermodynamic phase–Diurnal sampling accomplished by AM and PM polar orbiting satellites (especially Terra and Aqua)–Multilayer cloud structure estimated from both passive and active sensorsLong term trends require merging data from various sourcesInternational Satellite Sensors for Cloud Detection and Optical PropertiesInternational Satellite Sensors for Cloud Detection and Optical PropertiesCloud detection/masking–Multispectral and/or multiview imagers with appropriate spatial resolution, lidar, radarCloud thermodynamic phase–Multispectral imagers with SWIR and/or IR (8.5 µm) bands–Polarimeters with multiangular views and good spatial resolution–Lidars with depolarization capabilityCloud top