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Jean-Jacques Morcrette

APRIL 1990 JEAN-JACQUES MORCRETTE 847Impact of Changes to the Radiation Transfer Parameterizations Plus Cloud Optical. Properties in the ECMWF Model JEAN-JACQUES MORCRETTEEuropean Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, Berkshire, England(Manuscript received 10 July 1989, in final form 18 October 1989) ABSTRACT A new radiation package

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W. J. Koshak and R. J. Solakiewicz

composed of optical groups, and each optical group is composed of optical events (see Mach et al. 2007 ). Note that x is not limited to flash-level properties; for example, one could use the area of the first group in a flash rather than flash area itself or both. In general, one is free to choose any optical information from the optical data (including concocting derived variables from the data); hence, the list of possible optical characteristics is virtually unlimited. However, a certain set of

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C. M. R. Platt, S. C. Scott, and A. C. Dilley

15 FEBRUARY 1987 PLATT, SCOTT AND DILLEY 729Remote Sounding of High Clouds. Part VI: Optical Properties of Midlatitude and Tropical Cirrus C. M. R. PL^TT, J. C. SCOTT AND A. C. DILLEYCSIRO/Division of Atmospheric Research, Aspendale, Victoria, 3195, Australia(Manuscript received 1 June 1986, in final form 23 September 1986) ABSTRACTA lidar (0.694 ~m wavelength

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C. M. R. Platt and A. C. Dilley

MArl981 C.M.R. PLATT AND A. C. DILLEY 1069Remote .Sounding of High Clouds. IV: Observed Temperature Variations in Cirrus Optical Properties C. M. R. PLATT AND A. C. DILLEYCSIRO Division of Atmospheric Physics, Mordialloc, Victoria, Australia 3195'(Manuscript received 17 July 1980, in final form 20 January 1981)ABSTRACT The results of a ruby lidar (0.694/zm

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Wei-Liang Lee and K. N. Liou

optical properties, only the data with zero cloud fraction were selected. Other necessary environmental variables, such as temperature, pressure, and water vapor profiles, total ozone burden, and chlorophyll concentration, were taken from the Moderate Resolution Imaging Spectroradiometer (MODIS)/ Terra database. Figure 8 shows a comparison of the total downward solar flux, the total upward flux, and albedo between model results and observations. The maximum absolute difference between the two, the

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Xiaodong Liu, Libin Yan, Ping Yang, Zhi-Yong Yin, and Gerald R. North

document the large seasonal variations in the AOD modulated by the monsoons. Moreover, the monsoon transitions can affect the microphysical and optical properties of aerosols over the tropical Indian Ocean ( Corrigan et al. 2006 ). During the boreal summer when the atmosphere over the Asian continent becomes much warmer than the neighboring ocean surface, the lower-tropospheric warm moist air moves from the Southern Ocean to the Arabian Sea, India, and the Bay of Bengal after crossing the equator and

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Manuel Antón, Antonio Serrano, María L. Cancillo, JoséM. Vilaplana, Victoria E. Cachorro, and Julian Gröbner

optical properties and air mass characterization at El Arenosillo AERONET site (in Spanish). Ph.D. dissertation, Universidad de Valladolid, Valladolid, Spain, 237 pp . Vilaplana, J. M. , 2004 : Measurement and analysis of ozone and UV solar radiation at El Arenosillo-INTA (Huelva, Spain) (in Spanish). Ph.D. thesis, Universidad de Valladolid, Valladolid, Spain, 247 pp . WMO , 1997 : Instrument to measure solar ultraviolet radiation. Global Atmosphere Watch Tech. Rep. 125, 51 pp . WMO , 2003

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Renske M. A. Timmermans, Martijn Schaap, Peter Builtjes, Hendrik Elbern, Richard Siddans, Stephen Tjemkes, and Robert Vautard

countries. Spaceborne observations of aerosol optical depth (AOD) have the advantage of providing full spatial coverage (although only during daylight and cloud-free conditions) and—in principle—consistent data for the whole European region. Thus, synergetic use of satellite measurements, models, and ground-based measurements may be useful to improve the insight into aerosol distributions in Europe. Assimilation experiments, in which satellite data have been combined with models, have shown that current

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C. M. R. Platt, S. A. Young, R. T. Austin, G. R. Patterson, D. L. Mitchell, and S. D. Miller

also supported by ARM. The radars and microwave radiometer were sited close to the CSIRO lidar and infrared (IR) radiometer, providing a powerful system for studying cloud structural, optical, and microphysical properties. The basic scientific objective of MCTEX was to improve knowledge of the dynamics and interaction of the physical processes controlling convection over the Maritime Continent. One “component scientific objective” was to document the radiative properties of convectively generated

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M. Hess, P. Koepke, and I. Schult

The software package OPAC (Optical Properties of Aerosols and Clouds) is described. It easily provides optical properties in the solar and terrestrial spectral range of atmospheric particulate matter. Microphysical and optical properties of six water clouds, three ice clouds, and 10 aerosol components, which are considered as typical cases, are stored as ASCII files. The optical properties are the extinction, scattering, and absorption coefficients, the single scattering albedo, the asymmetry parameter, and the phase function. They are calculated on the basis of the microphysical data (size distribution and spectral refractive index) under the assumption of spherical particles in case of aerosols and cloud droplets and assuming hexagonal columns in case of cirrus clouds. Data are given for up to 61 wavelengths between 0.25 and 40 μm and up to eight values of the relative humidity. The software package also allows calculation of derived optical properties like mass extinction coefficients and Ångström coefficients.

Real aerosol in the atmosphere always is a mixture of different components. Thus, in OPAC it is made possible to get optical properties of any mixtures of the basic components and to calculate optical depths on the base of exponential aerosol height profiles. Typical mixtures of aerosol components as well as typical height profiles are proposed as default values, but mixtures and profiles for the description of individual cases may also be achieved simply.

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