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CLOUD DYNAMICS William B. Rossow July 2008 Slide 2 Global Distribution of Cloud Water and Water Vapor Slide 3 CloudSat First Light Slide 4 CLOUDS ARE NOT AN EQUILIBRIUM STATE USUALLY NOT EVEN BALANCE OF RATES Slide 5 Schematic Cloud Microphysics Slide 6 CLOUDS ARE EMBEDDED IN THE GENERAL CIRCULATION NON-LOCAL DYNAMICAL META-STATE Slide 7 Slide 8 TWO CRITICAL PHASE CHANGES PHASE OF CLOUD PARTICLES SIZE OF CLOUD PARTICLES, PRECIPITATION ONSET NUMBER OF CLOUD PARTICLES IS NOT TOO CRITICAL Slide 9 Effective Radius (m) for Liquid Clouds (Temperature > 273 K) NOAA-14 for 1995 Precipitation Onset Slide 10 Effective Radius (m) for Ice Clouds (Temperature < 260 K) NOAA-14 for 1995 Precipitation Onset Slide 11 DYNAMICAL ANALYSIS APPROACHES ATTRIBUTE COMPOSITES LAGRANGIAN EVOLUTION STATE TRANSITIONS Slide 12 Slide 13 FRACTION OF CS THAT PENETRATE Slide 14 Storm Tracks Slide 15 Slide 16 Slide 17 Slide 18 Monthly Variation of More Convective State in Tropical Longitude Sectors Slide 19 CLOUD PHYSICAL PROCESSES TIME CLIMATE TIME FEEDBACKS TIME CLOUD STATE DEPENDENT RELATIONSHIPS Slide 20 Slide 21 BACKUP SLIDES Slide 22 Thanks to a Cast of Hundreds Radiation Codes: Lacis, Mishchenko, Pardo, Cairns, Travis Cloud Detection Methods: Arking, Briand, Coakley, Desbois, Hahn, Harrison, Minnis, Mosher, Ruprecht, Seze, Simmer, E. Smith, Stubenrauch, Vonder Haar, Warren, Wylie ISCCP Participants: US, Canada, France, Germany, UK, Japan, China GISS-ISCCP Team Leaders: Bishop, Kinsella, Garder, Golea, Walker Valued Advice: Bates, Curry, London, Raschke, Schiffer, Stephens, Wielicki Analysis: Aires, Carlson, T. Chen, Garder, Del Genio, Fu, Han, Jakob, Jin, Liao, Lin, Luo, Machado, Pearl, Polak, Prigent, Roebeling, Romanski, Rozendaal, Siqueira, Stubenrauch, Tselioudis, Walker, Wang, Xu, Ye, Y-C. Zhang Slide 23 Effective Radius (m) for Mixed Clouds (260 < Temperature < 273 K) NOAA-14 for 1995 Slide 24 OUTLINE --- Some Recent Results CLOUD MICROPHYSICS STORM CLOUDS skipped -- CLOUD-TRACKED WINDS CLOUDS & GENERAL CIRCULATION Slide 25 Average Cloud Particle Sizes Slide 26 STORM CLOUDS Storm as Perturbation of Mean State Slide 27 Slide 28 Energy Cycle of Atmosphere Zonal Mean Available Potential Energy Eddy Available Potential Energy Eddy Kinetic Energy Zonal Mean Kinetic Energy Baroclinic Cycle Gz Ge Dz De Slide 29 First Determination of Gz and Ge from Observations Cooling of Winter Poles Winter Storms Summer Monsoons GZGZ GEGE Slide 30 Annual Mean Generation of APE Sign of G E Confirms Lorenz estimate and Contradicts Peixoto & Oort GZGZ GEGE Slide 31 Current Cloud Property Data Sets (Quantityinstantaneous error, mean uncertainty, source) Cloud Cover 15%, 5%, satellite, surface weather obs. Cloud Top Temperature 3-6K, 2K, satellite Cloud Top Height 0.5-1.9 km, 0.3 km, satellite Cloud Optical Thickness 25%, 10%, satellite Cloud Particle Size 2 m (liquid), 10 m (ice), 1 m (liquid), 10 m (ice), satellite Cloud Water Path 15% (liquid), 200% (ice), 10% (liquid), 100% (ice), satellite Cloud Base Temperature 3-6K, 2K, surface obs. Cloud Base Height 0.5-1 km, 0.3 km, surface obs. Precipitation 30%, 15%, satellite, surface obs. Lightning 30%, 10%, satellite Whats Left to Do? Cloud Vertical Structure!! Slide 32 Zonal Seasonal Mean Pressure-Latitude Cross- Sections of Cloud Frequency of Occurrence Land DJF Land JJA Ocean DJFOcean JJA Slide 33 EXTENDING THE RECORD Slide 34 Slide 35 Slide 36 Slide 37 Annual Mean Effective Radius (m) Liquid and Ice for Land and Water NOA/NOM for 1995 Slide 38 Annual Mean Effective Radius (m) Liquid and Ice for Morning and Afternoon For 1995 Slide 39 Regional (30-60N) Monthly Mean Effective Radius (m) Liquid and Ice for Water and Land For 1995 Slide 40 Regional (30-60S) Monthly Mean Effective Radius (m) Liquid and Ice for Water and Land For 1995 Slide 41 Regional (0-30N) Monthly Mean Effective Radius (m) Liquid and Ice for Water and Land For 1995 Slide 42 NOA 1995 Annual means by Cloud type Effective Radius (Microns) Slide 43 NOA&NOM (combined)1995 monthly means Effective Radius (Microns) LAT REGION >60 Slide 44 NOA&NOM (combined)1995 monthly means Effective Radius (Microns) -30 NOA&NOM (combined)1995 monthly means Effective Radius (Microns) LAT REGION>-90 Slide 46 Slide 47 Surface Pressure Anomalies Slide 48 Slide 49 SMALL CLOUDS USED TO DETERMINE HORIZONTAL WINDS Slide 50 Composite Cyclone Cloud Vertical Structure Slide 51 Slide 52 Average Cloud Droplet Size as Function of Cloud Optical Thickness Precipitation Onset 11m 16m Slide 53 Weather State Slide 54 MeanCStmpCSradiusMeanCStmpCSradius MEAN CLOUD TOP TEMPERATURE VERSUS SIZE Slide 55 MINIMUM CLOUD TOP TEMPERATURE VERSUS SIZE Slide 56 Composite of Diabatic Heating of Atmosphere with Cyclone Strength Slide 57 Slide 58 Correlation of Microwave Polarization Features and Lightning Cloud Top TemperatureLIS Detection Slide 59 Evolution of Tropical Convective Systems