Importance of clouds climate life ocean radiation hydrological cycle clouds & precip + aerosols latent heat + loading dynamics electricity aqueous chemistry Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 1 / 39
Global mean energy budget [W m 2 ] Solar reflected 100 TOA Incoming solar 340 Imbalance 1 Thermal outgoing 239 Atmosphere Solar reflected by clouds, aerosol and gases Solar down surface 185 Solar absorbed 79 Thermal outgoing 199 76 Atmospheric Greenhouse window gases 40 24 Earth`s surface Imbalance 1 Absorbed solar 161 Sensible heat 20 Latent heat 84 Up surface 398 Down surface 342 Fig. 11.1 (Lohmann et al., 2016) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 3 / 39
Motivation Cloud types Extra Cloud radiative effect (CRE) & precipitation IPCC, AR5, Fig. 7.7: Annual mean CRE (2001-2011) from CERES satellite data and precipitation (1981-2000) from GPCP (Boucher et al., 2013) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 4 / 39
Robust cloud responses to greenhouse warming Rising High Clouds Broadening of the Hadley Cell Narrowing of Tropical Ocean Rainfall Zones Rising High Clouds Rising of the Melting Level Poleward Shift of Storms Less Low Clouds More Polar Clouds Equator 30º 60º Pole IPCC, AR5, Fig. 7.11 (Boucher et al., 2013) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 5 / 39
Motivation Cloud types Extra Summary of different cloud types Fig. 1.3 (Lohmann et al., 2016) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 7 / 39
Cloud types Cumulus (Cu): vertical development Stratus (St): layered cloud Cirrus (Ci): ice clouds Low base with vertical extent: Cu, Cb, Ns Low base and layered (0-2 km 1 ): St, Sc Mid level clouds (2-7 km): As, Ac High altitude ice clouds (5-13 km): Ci, Cs, Cc 1 heights refer to mid latitudes Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 8 / 39
Cloud type exercise Take 10 minutes to discuss with your neighbor: What cloud type is that? Which synoptic situation could have caused its formation? Is it composed of cloud droplets or ice crystals? Will it form precipitation? Does it predominantly cool or warm the Earth surface? Sources: Karlsruher Wolkenatlas: http://www.wolkenatlas.de Mainzer Wolkenbildergalerie: http://www.cloudgallery.mpich.de/index_1.htm Houze s cloud atlas: http://www.atmos.washington.edu/atlas/ Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 9 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 10 / 39
Altocumulus (Ac): gray or white broken sheets, elements, bands, rounded masses Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 10 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 11 / 39
Stratus (St): very low, gray, uniform layer (sun outline very distinct when visible) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 11 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 12 / 39
Cumulus (Cu): white, detached, dense elements with shape outlines and vertical growth Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 12 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 13 / 39
Cirrocumulus (Cc): thin, white sheet or patch without shading composed of very small ripples, grains Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 13 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 14 / 39
Nimbostratus (Ns): gray, dark, diffuse, uniform cloud with steady precipitation Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 14 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 15 / 39
Cirrostratus (Cs) with 22 halo: thin, white, translucent veil either fibrous or smooth in appearance (halo) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 15 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 16 / 39
Cumulonimbus (Cb): very deep, dense and precipitating with flattened top Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 16 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 17 / 39
Stratocumulus (Sc): low, gray-white, patch or layer with elements, rolls or rounded masses Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 17 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 18 / 39
Cirrus (Ci): detached, white, filaments or patches with fibrous appearance or silky sheen Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 18 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 19 / 39
Altostratus (As): uniform or striated gray/blue sheet (no halo but sun behind grounded glass) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 19 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 20 / 39
Banner cloud: A cloud plume often observed to extend downwind from isolated, sharp, often pyramid-shaped mountain peaks, even on otherwise cloud-free days Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 20 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 21 / 39
Fog: Water droplets suspended in the atmosphere in the vicinity the earth s surface that affect visibility Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 21 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 22 / 39
Contrail: A cloud like streamer frequently observed to form behind aircraft flying in clear, cold, humid air Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 22 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 23 / 39
Cb penetrates cirrus: Wind shear above the anvil cause the upper part of the anvil to be transported to the left Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 23 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 24 / 39
Chaotic sky Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 24 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 25 / 39
Mother-of-pearl cloud or polar stratospheric cloud: Thin cloud between 20-30 km altitude Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 25 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 26 / 39
Kelvin-Helmholtz wave cloud: Kelvin-Helmholtz instability can occur when velocity shear is present within a continuous fluid or, when there is sufficient velocity difference across the interface between two fluids. It s manifested in form of waves. Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 26 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 27 / 39
Roll cloud: relatively rare type of arcus cloud. Arcus cloud: low, horizontal cloud formation associated with the leading edge of thunderstorm outflow, or occasionally with a cold front even in the absence of thunderstorms. Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 27 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 28 / 39
Asperatus cloud: rare, newly recognized cloud formation. Asperatus (roughened or agitated waves) are related to undulatus (wavy bases) clouds. They appear dark and storm-like, but tend to dissipate. Particularly common in the US Plains during morning or midday after thunderstorms. Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 28 / 39
Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 29 / 39
Noctilucent cloud: can be found around 75-85 km (just below the mesopause) over the summer pole between 50-70 N/S. They can only be observed when the Sun is below the horizon. Picture courtesy Blaz Gasparini Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 29 / 39
Schematic of layer clouds Houze s cloud atlas: www.atmos.washington.edu/atlas/ Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 30 / 39
Stratus cloud cover Figure: Stratus cloud cover averaged over 1983-1990 from the International Satellite Cloud Climatology Project (ISCCP) Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 31 / 39
Importance of microphysics for stratus Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 32 / 39
Importance of microphysics for stratus Durkee et al., J. Atmos. Sci., 2000 Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 33 / 39
Importance of dynamics for stratus Klein and Hartmann, J. Atmos. Sci., 1993 Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 34 / 39
Schematic of cumulus clouds Houze s cloud atlas Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 35 / 39
Schematic of mid-level clouds Houze s cloud atlas Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 36 / 39
Schematic of cirrus clouds Houze s cloud atlas Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 37 / 39
Motivation Cloud types Importance of dynamics for cirrus Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Extra (Fig. 5.29 Houze, 1993) Sept 19, 2017 38 / 39
Importance of microphysics for cirrus Ulrike Lohmann (IACETH) Physics and Dynamics of Clouds and Precipitation Sept 19, 2017 39 / 39